I'm a highly accomplished electronic engineer in several things including power management systems and devices used in alternators and battery management systems. I passed by your video thinking "what is this non sense". I was quite surprised to find that you are quite technically correct in this video. Excellent job.
I remember when alternators first come out I was working for the Ford company on the coast of Mississippi. They sent us to auto school in New Orleans and they explain the function of the alternator they were going to replace the generator on cars and they replace them were the last cars, we had that had generators 1960 alternators took their place the fields turned inside the armature right reversed to what a generator did and you had to have 1 1/2 volt to excite them to make them work. If you had a dead battery you could push that car all day long and it would never generate any power that was a long time ago we have come along way now with electronics . Grate job Clark as always
And people mistakenly think batteries and charging systems are simple and don't understand why I think they aren't. This post and the following comments/discussion support my contention. I rarely read comments, but I took probably an hour or more to go through these. Very informative and time well spent....👍👍
Thanks for the great breakdown, Clark! I'm a marine electrician and have hesitated to do lithium installs on my customers' boats because of the off chance that a BMS opens the circuit, frying the alternator and everything else. I REALLY like that the lead battery is there as a guardian.... and now with ways to thermally protect even internally regulated alternators I'm even more excited. I'm currently cruising, but will be back to work in a few months. I look forward to the next video and the possibility of installing a bank manager. Thanks again for the great video and sharing your knowledge!
No chance that a soft start 50A BMS can fry the alternator when a 90A compressor, or a 200A winch with ugly back emf, doesnt. The starter battery has very low impedence and is the voltage clamp, in much the same way as a giant zener diode
The way the author of this channel explains and teaches reminds me of my enthusiasm for science as a youngster in class (late 70s-early 80s). I’ve had deafness since birth, and what little I could understand verbally was supplemented by visuals in the classroom. The author has many of the qualities of those teachers I admire and I appreciate that very much. Thank you so much. As an adult, with my deafness, TH-cam, with its closed captioning, has made the educational aspects much more accessible thank goodness. With the help of YT, I’m attempting to design & build a 100ah lipo battery system for my truck with limited space. I’ve purchased a Renogy 12V 30A DC to DC Charger with MPPT, On-Board Battery Charger. At the moment, after learning from this video, It’s clear that I need a system that is plug and play. I don’t have the capacity to understand all the science at play here. I use my truck daily as part of my job doing outreach and reliability and safety is my utmost concern. As well as affordability, which is why I’m trying to design and build it myself. I just wish there was a complete system I could install myself with more confidence in those goals. Any suggestions? Thanks for “hearing” me explain my situation in advance. Kind regards.
Thanks Clark. I'm finding you far more straightforward and informative than the battery manufacturers. Q: If I go either the dc-dc or Battery Bank route, d o I need to install a monitor or alarm/fuseto let me know if it fails? Or, is my first indication smoked alt diodes. I sent an inquiry to LiTime, asking if they are recommending any sort of dc regulator. So far, no response. And I'm finding lithium battery ads pushing their products as "drop in replacements" for lead acid batteries. The alternator is a convenient back-up for cloudy days, so I would really like to retain it as a charging source. However, I've just done an alternator replacement. It was not fun, easy, or cheap, and I'm not looking forward to doing it again soon. Thanks again for this video. It's a valuable service for any of us who go lithium! 4:56
Li is nowhere close to a drop in replacement for Pb. Even the li charger controllers available today don't charge it right for a long life. To keep your alternator cool the best solution is an external regulator with a temperature sensor. I've always used Balmar. People I respect like Sterling. BankManager and some lead will keep your alternator's diodes safe and charge your Li property for a long life. (So there's my commercial. ) www.emilyandclarksadventure.com/bbms I'm not a fan of DCDC chargers. I think I go into it in the FAQs in the link above
Excellent! I use a DC DC converter from 12v to 24v since my house battery is 24v, but I never thought of a thermal switch as a protection. Very simple and cheap :-)
Great information as usual. Your deep understanding of electrical engineering and excellent explanations are what make your technical videos so great. Often other channels, even when providing technical details, are just repeating what they were told by equipment manufacturers. Which is not all bad or wrong, just sometimes not quite all the details that we really need to understand all the issues and make the best decisions. I am looking forward to the alternator tear down. I have often seen people say that you should basically throw away an alternator if you blow the diodes and that has always seemed like it shouldn't be that hard to fix. Thanks for all the great videos. I don't even own a boat yet and may not for several more years, but I'm tempted to buy a BBMS just in case you quit making them. So please give advanced notice if you every decide to quit. But hopefully you will be hugely successful with it and keep making them.
So nice of you to say Jim. As for fixing alternators, that could be true based on the cost of US labor. And because of that culture parts are hard to find. Go someplace like the DR or Mexico and everything is fixed. So parts are readily available.
@@Clarks-Adventure The Alternator parts are all pretty easy to find, at least here in the area around Tampa Bay. Alternator Starter Parts Wholesale in Port Richey Florida is a great resource for (as you might have guessed) alternator and starter parts since the owner is quite passionate about not only having the parts but also the quality of the parts. They recently got me an American Made higher quality long nose starter drive than most put into a rebuilt Marine 454 inboard and got it overnight for pickup at no additional charge. Had a nice motorcycle ride on a beautiful Florida day when I went to pick it up and was able to look a person in the eye and shake a hand. Hopefully his son will continue running the enterprise when he retires. How many folks throw out small appliances just because its cheaper to say replace a $125 portable ice maker because it costs too much to pay someone to put 3 drops of sewing machine oil on the bearings of the computer fan that was used on the condenser. We often don't think of the cost of waste on the environment when we do that and only look at the Dollars and Cents or whatever currency you dealing with. I just fixed a small appliance by taking the 15 minutes to oil the computer fan inside it instead of throwing it away and dropping $125 on a new one. That was like getting paid at a $500 an hour payrate for 15 minutes of work plus it took less time than it would have to purchase a replacement, unbox it, etc, etc along with dispose of the old one. Perhaps we should have a moment of silence for the demise of all the Emmet's and their Fix-It Shops (remember Mayberry) across the country who've fallen victim to the disposable culture we live in. Keep up the good work but don't keep working so hard at it that you don't have enough time to pause and do the simple things like comb your hair. ;> I technically gave you three likes on this one but the counter sadly only accepted the first one. Best!!!
We’ve been binge watching your content lately. I love the idea of a Lead/Lithium hybrid bank and it looks like you did a great job on your BBMS product. I’m looking forward to this upgrade soon!
In just editing an endorsement video from a buyer now. So fun to see how much people like this. I think I'll release it as this week's video. He put it in a really big system.
For protection from sudden BMS shutdown, why not use a zener diode shunt? A zener diode is non-conductive until the threshold voltage is reached. Then it becomes a near open circuit. If you were to put a zener between the positive and negative charge wires, the voltage spike would be limited. Since the voltage spike would only last a few hundred milliseconds, the zener would be able to dissipate the excess energy with no problem. The alternator regulator will respond and bring the voltage back to normal and the zener shunt will turn off. I did a quick search and found 50W 50V and a 50W 35V zener diodes for around $10.
I've tried a zener in the past. It blew like a fuse. I don't remember the specs. Maybe there are better ones now. It's going to have to dissipate 35vx140a, that's like 5kw. That's a lot of power. The time wouldn't be the 400ms. That's how long before the alternator diodes fry and the zener it trying to protect those. It's going to be until the regulator shuts down and then the time it takes for the rotor field to dissipate. If you run the test tell me how it goes. I don't want to risk my alternator.
An alternator under full load can be putting out 200+A for a few ms after the load disappears, your 50W zener will be taking 2000+W during that time. You need something more robust to take the spike. A 15V zener driving the gates of a dozen 250W MOSFETs to spread the heat and 5W 0.1 ohm balance resistors between each source and negative rail might work for clamping surges to about 18V. (15V zener + 10A x 0.1 ohm + 2V of gate drive for logic-compatible FETs = 18V) Since the name of the game is slowing down the voltage spike so the regulator can react before voltage gets out of hand, a 500 000uF 25V capacitor bank could also do the trick.
@@DrJuan-ev8lu I thought about that but wouldn't that make it worse because even if you had a super cap rated for that kind of voltage (100+v spike) it would dump it right back into the battery once the BMS came back online potentially damaging the battery. I suppose the argument would be that it couldn't absorb that much voltage in that timeframe but you'd have to have a bank rated to well over 100v and protection circuits would be vulnerable.
@@fatillacing4131 You can sink the excess voltage with a TVS Diode. If voltage spike goes high enough a varistor will likely have adequate joule capacity
Your content and presentation is excellent. In the upper threshold of TH-cam influencers that I've watched over many years. I hope you keep up the good work and are taking care of financially for it
The service manager at the marine mechanic facility I use just talked me out of using a lifepo4 battery for my starting motor. He was worried about how the charging system would be affected on my mercury pro xs. Told me to stick with agm and that’s exactly what I plan to do. Nice video. Very informative.
@Clarks-Adventure didn't even know they made lithium batteries for starters, I've only seen guys using supercapacitors for start an engine. I've got the ecoflow system so I use their alternator charger to charge my 3.7 KW battery.
I'm currently filming a liTime 140ah battery that can start big outboards. I've already started my friends 115hp 4 stroke It looks like an interesting battery. Video coming
I love the content you guys are creating. Watched a ton and I feel I’ve learned so much. I currently liveaboard but I’m new to this life. Being a construction worker I’m financially challenged but very handy. With this information I’ve been able to enter a new way of life with confidence. Thank you so very much for all the knowledge I’ve gleaned from your content. So badly want a bank manager for my Pearson 40’s solar system and I’m starting from scratch. ❤
Your flat (most times installed serpentine) belt also has substantially more surface area compared to a typical "V-Belt" so it wears out much more slowly. Also, a flat belt usually has a spring tensioned self-adjusting pulley that is easy to adjust tension for belt removal and replacement unlike a fixed position pulley on V-Belts which require more tools and frequent adjustment.
@@Clarks-Adventure Not always I have pulled down many engines and found that the amount of tension applied by serpentine belts shows wear on the front upper main bearing shell at about 11 o clock which shows they often have too much tension applied in the design stage, So not everything is all apples in every case
I have motorhome with lead starting batteries and lithium house batteries. When the engine is running, the Alternator charges both systems. This means the lead batteries are there when the lithiums turn off at full charge, and the Alternator is protected from damage. When the ignition is turned off, the lead batteries are completely isolated, they will not charge with shore power or solar panels. But there is also no power draw, so they can sit idle for weeks at a time. When the ignition is turned off, the 2 battery banks are cemetery isolated.
An issue you should consider is with the engine running your Li is being charged like lead (not good) and then floated at voltage over 13.48 (really not good). Are you considering a change?
@@Clarks-Adventure I thought you were giving me a green light for my motor home to have a lithium house battery. Now you are talking contrary with this response. I'm left confused once again.?? So I still won't buy a lithium battery for the house side of the motor home. And I thought lithium was to be charged at 14.4 to 14.6 volts to 100%. state of charge 13.6 volts. If I am charging and floating like a lead acid battery, how would the lithium battery ever get to full charge to shut down the BMT and destroy the alternator if no lead acid battery were present?
More solid content, well organized. I'm definitely sold on the Bank Manager....but I don't have any lithium yet, so that order will be awhile coming. Cheers.
These thermal switches are so cheap, I don't understand why all motors and alternators aren't thermally protected. I once burned out a Makita planer just planing some hardwood. You spend all that money on a power tool and they can't put thermal protection on the motor?
Great Lithium topic. If you have a Balmar with an expensive external voltage regulator, you can rig a switch that allows 50% output. You can run in 50% mode by default unless you want to "fast charge". Fast charging is used on exception and prolongs the wear on the water pump pully on my Yanmar 3GM30f motor.
I have a few more ideas. You can have a voltage sensitive relay that connects your lithium to your lead starting battery only when your alternator is charging the disconnects when lead battery voltage drops to its resting state. It won't matter if your lithium battery disconnects because your lead battery is still connected. You can also upgrade the BMS in your lithium battery, my JK BMS turns off charging when battery is full but still allows discharge so there should be a voltage there for your alternator to see and not shoot up in voltage, that's what happens with my solar inverter. You can also maybe have a decent capacitor in parallel with your battery to hold a voltage in case the BMS shuts off while the alternator is charging, in theory the alternator will sense the voltage in the capacitor and think its a fully charged battery. You can also remove the regulator and diode assembly in the alternator and manually power the rotor field with your ignition or a switch and connect the 3 phase stator to a 3 phase bridge rectifier to get your high voltage dc and with a suitably rated capacitor to filter the DC then connect the high voltage dc to a solar regulators pv input to simulate solar panels. The charge controller will then handle all the charging to the lithium battery. I will be trying this to make use of a fried diesel inverter generator. Great info about the overheating and thermal switch mod too.
My fix for this issue, tie in a supercapacitor in parallel to the battery. Iv'e actually blown out two solar charge controllers and nearly took out my inverter over a very similar issue. Smoke and flames, glorious flames! Many of the earlier LiFePO4 4 batteries had a lower cutoff voltage; right around 14.1 volts, the newer ones run around 14.6volts. Regardless, even if the BMS triggers, the cap provides enough cushion to allow the charging equipment to shut down safely. the supercapacitor did 2 things for me, it fixed this issue, it also allowed me to start fairly heavy motors rated at nearly the inverter capacity without issue.
Great video, Clark! I was about ready to go out and buy a DC to DC Charger when you told us that I didn't need one because I bought your Bank Manager.❤
I’m quite the opposite of the person below who stated they were highly trained and experienced in electrical systems. About all the training I have is enough to know sticking one’s tongue on a 9 volt battery or a fork in a 110v socket is definitely an experience I will remember for the rest of my life. To me electronics are similar to magic but what I will say sir is you definitely explained things in a way that even a caveman like me can understand. Thanks and I look forward to watching more of your videos. ✌🏽
Great video.... having the starter battery permanently connected to the alternator and hooking the lithium in parallel through a battery isolator solves the high volt issue, then with a long 10mm2 battery cable about 10 m long going to the lithium house battery gives enough resistance to limit charging current so the alternator does not run to long at full amps...which is what I did on my RV I love the vee belt comment as it was also known as a wedge belt, noisy friction stuff. I worry that the thermal switch solution may not be so good due to the inductive reactance of the field causing back emf high volts causing the thermal switch a problems..
@Dean-i4d Hi, thank you for your reply....I use a rather cheap 100Amp isolator at the front end near the driver, going down the back to a proper battery isolator down the back. It gives me the ability to starter assist from the house batteries, solar can charge both house and or starter, or if need be run house loads from starter and engine alternator if the house batteries ever failed me. The most charge I have ever seen going to the house batteries from the engine alternator was about 55 amps... which soon raised house battery volts a little and caused the amps to fall away. Lithium batteries do not mind 14.5 volts for their in built battery management to even cell charge... so there is just no need for DC to DC expensive kit if your willing to operate the battery inter connect manually.
I just found your channel. I assume your device will apply to an RV system? I have a dual alternator system as this vehicle was originally an ambulance. I have removed the rear batteries and now have the original dual battery system for the diesel under the hood. I have upgraded one of the alternators and plan on using the other alternator exclusively for my "House" batteries which are lithium. As I understand from your video, If I install a lead acid battery as an intermediate to the lithium batteries and install the Bank Manager to regulate the alternator it should help my second alternator live to charge the lithium battery bank along with 1200 watts of solar. Thank you for this video which has come up on my youTube home page!
Referring to diode failures, back years ago, I was having issues with cheap reman. alts. I found the issue was cheap diode bridges installed in the reman's. I found a source for plasma bonded diode bridges which fully eliminated the future failure issues. The cheap bridges were soldered diodes which we all know has a low melting point. The diodes were simply falling out of the alt on the road as I drove along. Now not all alts are constructed so the diodes can simply fall out of the cases, such as late model Fords or many others. Not that long ago, I was working on restoring a Ford 7.3L powered PU which I had installed a reman alt. One day I was working on something else and sparks just lit up the inside of that reman alt. It was on account of a diode bouncing around inside the case which in the end pretty much destroyed that unit. This is the second vid I've watched today from Clark and they were both educational. I've been working on engines in boats and autos most of my life and have learned something even today after over 40 years of mechanic work. Of course very little experience with LiFePo4 batteries in cars has been the case. I'm really liking the hybrid battery concept now.
Great Video ! The condition of the battery "spiking" is , I believe is known in engineering terms as "load dump " . I am amazed by how many people work in electrics or electronics, are unfamiliar\ with load dump , & its ability to destroy components. My first introduction to load dump was an automobile I had & the negative cable fell off the battery post (don't ask !) & every damned light that was "on" at the time instantly vaporized its filament.
Such an excellent video. I'm convinced you can confirm if my expensive way of keeping my alternator in check will work for my upcoming project. Mind you I'm installing these on a yamaha jetboat (because I have a very demanding audio system) So I bought an Epoch lithium battery 12v460Ah claims the following statement on the website: " CANBUS Communication allows BMS to communicate directly with Victron OS" I also bought a Balmar XT 250 alternator. I will be buying the all new Arco Zeus external regulator (it is a canbus enabled regulator similar to the wakespeed WS500) I will also buy a victron cerbo GX. I'm hoping the Epoch batteries internal BMS will connect to the Cerbo GX to be able to enable DVCC and then from the Cerbo GX to the Zeus regulator which then will control the Balmar alternator to shut off when my lithium gets full and stops accepting charge or out of balance etc any time it shuts downs. All concept and I already bought most of the expensive parts but really would appreciate if you would look into these specific products. I have a good feeling you will be familiar with the individual items I have listed and will have a stronger opinion on if they will be able to communicate in the way I'm hoping. Looking forward to your reply and thanks for the videos, cheers!
No I haven't put that exact system together as I solve this a different (better) way with my BankManager. It can't fail and actually charges your Li correctly unlike these devices. It's also much cheaper. I suggest you ask this question to the guys buying from.
I see so what happens if the Lithium BMS shuts down unexpectedly, does the starter Lead Acid Battery or AGM battery absorb the extra current so it doesn't damage the alternator plus all the other electronics?@@Clarks-Adventure
I'm usually not commenting on you tube clips, but i think i can add some useful info. For those who have newer boats with 2014+ Yanmar YM.. engines, they are all equipped with 125A 12V Valeo alternators, which have internal regulators - simple (dumb) voltage regulators. The video suggests to add thermal switch in the field current path to prevent overheating the alternator when LiFePO4 is used. Indeed, there is a Yanmar Tech bulletin out (YMTQTB17-007), which recommends to limit the charging current to 100A. This will limit the alt temp to 200 deg C, which seems high, but apparently is OK for Yanmar. Now, a thermal switch can accomplish this, but it does not address the voltage spike problem. Here is why. I'm assuming a typical scenario with lead acid starter and LiFePO4 house battery bank, both separated by a battery isolator. The LiFePO4 batteries typically use a battery monitoring circuit (BMC), which will shut off when a single cell (there are 4) reaches its max voltage. This shutoff happens instantly with severely unbalanced cells. The lead acid battery starter battery is normally fully recharged after a few minutes and therefore won't act much as a buffer raising the charge voltage above the 14.4V limit. The only way to remedy this is a controlled ramp down of the charging current so that the regulator can follow. So far i haven't found any specs for ramp down of BMCs, maybe someone can enlighten me.
Another down to earth and informative description...Question : related to the Lithium potential to destroy alternator diodes when a BMS suddenly cuts off the battery. If I make up 3 x groups of 3.2 v cells in paralllel (its for my 12v sailboat to replace the AGMs) If each of the 3 groups of 4 cells has its own BMS and 1 of the BMS shuts down a group of cells will the alternator diodes be affected? Is this an effective way to safeguard the alternator diodes.
Nope one BMS shutting down won't hurt the alternator. Nope it's not an effective solution Once the first BMS shuts down the other two suddenly get 33 percent more power are are likely to shut down ... Cascade thing Why not just do what I suggest? You are going to have a lead battery around to start that diesel. And there are now over 700binstalled BankManager systems that will keep your new li from being destroyed by being charged wrong.
very good insights for people, thank you Clark. 👍 Personally my next boatbis likely to need refurbishing and upgrades, along with replacements, Full wiring design check, Network Wiring, Lightning protection isolation and Bonding, New instruments (replacement originals that work, kept as spares for other boaters, and expensive but worth it Alternator, serpentine belts, external Regulator, standing rigging, running rigging, New Sails, and existing checked, valeted, and kept as a backup suit of Sails if good enough. That kind of thing. I'm still a bit wary of Lithium, after communicating with a Chinese Manufacturer. Like Lead, Lithium Hates being discharged below 50% Capacity, and you lose recharge cycles each time if you do it for longer life, they don't appear to like being charged over 85% apparently, so useful non damaging capacity appears to be between 85% and 50% , so a tual useable capacity would be 35% .? Now Lead Loves being charged to 100% right? So bon damaging capacity therefore looks to actually be 50% right, plus Lead batteries are easily and fully recyclable? Plus the extra weight, can help put displacement down low where it is useful. A badly treated AGM Battery can last as little as 18 months, but we'll looked after, 10 years. How long do badly treated Lifepo4 Batteries last ? What is their Maximum Life ? Information on those factors, are highly noticeable by their absence aren't they ? So I may go with deep Discharge Dual Purpose AGM, and Never Deep Discharge them (even with Lithium, deep Discharging Damages them. Any experience with Carbon Lead Clark ? They look interesting. As an aside, Offgrid on my Smallholding, I got 15 years outbof a bank of heavy Duty Cheap Agricultural Tractor Batteries, and only lost them thanks to Not forecasted extreme cold down to minus 45 degrees C cracking their cases. Never discharged below 50% and usually a couple of volts higher than that. I won't have "Normal" Lead acid Batteries on a boat though, must be sealed. Best Wishes. . Bob 👍
Hi Bob, Carbon lead is very interesting and people I respect are having good luck with them. I haven't owned a set myself. I think you might want to broaden your research into LiFePO4. I think you will find evidence that a lot of your ideas about life and discharge are not exactly right. It's still early days for this technology but it seems to me that Lifepo4 can be fully charged as long as your charger can accurately know where 100% is. That can't be done with voltage alone so basically only my BankManager can do this safely. They seem OK with more than 50% discharge. In fact they should be stored for the long term at 50% charge. I set my lower limit to 20% so I get a working spread of 80% of rated.
@@Clarks-Adventure Good points Clark, Lifepo4 is indeed a Bit different, to Lithium, but that 85% charge maximises the service life of mobile phone batteries and Tablet batteries may point to it pointing that way for Lifepo4 as well. It was a pretty good Chinese Lifepo4 Batteries Manufacturer (pretty sure looking to sponsor me with a Housebank Set, to help them determine what the maximum useful service life could be if properly treated ) who was quite firm about the number of Recharge Cycles being harmed badly, if discharged below 50% Capacity, if done often. I suspect there could well be a way of treating Lifepo4 batteries, to get a useful service life of 20 plus years tbh. Though Tester Will Prose has said that, or at least strongly hinted, that Lifepo4 batteries will self destruct internally, a long before Cycle life can be reached. Now That I find worrying worrying enough, to seriously consider whether even a free Housebank set is really worth the bother of testing, and is certainly serious food for thought. Thanks for the thoughtful response Clark, Best Wishes. Bob (who does love testing stuff ) 👍⛵️✨️✨️✨️✨️✨️
@@Clarks-Adventure PS Me again Clark. I think I'm going to let others find out about Lifepo4 possible service Life, and as 10 years for AGM properly treated is now solidly established, I think a Carbon Lead Housebank with AGM e gine, bowthruster, and Windlass batteries as a setup for long term testing, will probably be the route I go , thinking about it. Thanks again. Bob. 👍 the edit was because the message decided to post itself before completion, so added the change of direction for me as well . 🤣
@@braithmiller eta dropped letters from words. Luckily they aren't the only manufacturers, and Carbon Lead can be cheaper by a fair bit than Lifepo4 when on offer. AGM too, for a solid 10 year service life if treated properly, such as Never Deep Discharging any Deep Discharge Battery for starters, no matter the chemistry of its construction. You just need to develop an appropriate Battery Bank size, with a good routine for managing it. One Boat Owner, no names, no pack drill, an engineer ffs, absolutely Trashed his new AGM Batteries inside 18 months, and replaced them with very expensive Lifepo4 batteries. Did he change his management regime ? Nope, so bets may be taken on how long efore he trashes those Lifepo4 batteries. I would put money on them not lasting very long at all, and likely less than 5 years. Expensive lessons should be the best Education, Right ? Should have learned from his AGM bank that he wasn't doing things right imho, a nice guy, and he will probably figure it out in the end. 🤔
(00:00) - Introduction Clark introduces the topic: Lithium-Ion phosphate batteries vs. alternators. Common question from viewers: How to deal with alternators when using lithium-ion phosphate batteries. (00:43) - Lithium vs. Lead Batteries Lithium-ion phosphate has a Battery Management System (BMS) that protects the cells by shutting off the battery when it goes outside the safe zone. Lithium batteries can absorb power faster compared to lead batteries, which need slower charging above 80%. (01:56) - Alternator Function Alternators produce power (voltage × amps). If the battery disconnects, the alternator's voltage spikes, potentially damaging the diodes. (03:13) - Problem Explanation Sudden loss of power when lithium battery shuts off, causing alternator damage. Voltage spikes can affect other electrical components on the boat. (04:21) - Example of a Real-Life Issue A boat with lithium batteries loses power after the BMS shuts down the battery, and the alternator's diodes are burned out. The owner didn't realize the issue until months later. (05:29) - Solutions Classic solution: Keep the battery connected to the alternator at all times, but not ideal with lithium as the BMS needs to disconnect for protection. DC to DC charger: Possible but inefficient due to power loss. Hybrid system: Combine lead and lithium batteries with a "bank manager" to prevent damage. ABYC solution: Expensive modification with a special BMS that sends a signal to shut down the alternator before the battery disconnects. (08:15) - Power Absorption Differences Lithium batteries can absorb power without tapering off, unlike lead batteries. This creates more strain on alternators, especially high-output ones. (09:18) - Heat and Alternators Alternators generate heat when producing power. Fans help cool the alternator, but more powerful alternators create more heat. (11:03) - Upgrading Alternators Upgrading to a higher-amp alternator can cause more heat. High-output alternators may overheat if not used properly. (12:28) - Proper Alternator Use Start engine, raise anchor, and avoid letting the engine idle too long. Alternators work best at higher RPMs with good airflow. Avoid revving the engine while in neutral as this generates heat without cooling. (13:32) - Overheating Alternator Risks Operating alternators at maximum output without proper airflow can damage them. High-temperature alternators may require thermal management systems. (15:54) - Solutions for Heat Management Use an external regulated alternator with thermal protection to avoid overheating. Install a thermometer on the alternator for monitoring. (17:08) - Thermal Switch Option Use a thermal switch to cut power when the alternator reaches a set temperature (e.g., 110°C). This switch can protect alternators from overheating. (18:20) - Modifying Alternators Internal regulator alternators may need to be modified to include thermal switches. Modification allows for better heat management and protection. (19:28) - Upcoming Video and Closing Clark will explain how alternators work internally and how to modify them for better heat management. Final thoughts on protecting alternators when using lithium-ion phosphate batteries. (20:02) - Conclusion Clark hopes this video answers common questions about alternators and lithium batteries. Viewers can ask more questions on Patreon for further videos.
@chazgeisler6213 Thank you so much for this. I hope you planned on me incorporating your work into the description. If you like doing this feel free to do this for any of my videos and If you would like to help on new videos send me an Email to SailingTemptress@gmail.com and we can talk about sending you links to my videos way before I publish.
Clark, loved the video. I have a very challenging problem though. My boat has 2 engines and 2 separate banks. Both banks can be charged by either alternator through a 2 alternator, 2 battery isolator. This is great when smaller similar batteries are used. My case involves a house battery bank (starboard) of lithium rated at 700 amp hours with 6 batteries in parallel. It is very unlikely that all 6 batteries would shut off, especially since the alternator really only wants to stop charging at about 14.2 volts. Since it goes through the isolator, a voltage sense wire is needed to the alternator due to about a 0.7 volt drop through the diodes in the isolator. This is one of my problems as the non house side with lead gets fully charged rather quickly essentially shutting down that alternator and now it contributes nothing through the isolator. This leaves the other house alternator doing the work to charge a 700 amp lithium battery. As you noted about alternator speed, I ussualy run 900-1100 rpm and air flow is probably not sufficient to cool this alternator resulting in a melted brush cage in my last alternator. My thought was to use a dc-dc charger from the Port Engine battery charging the Starboard engine that has the house batteries. The charger failed within about 10 hours running though. This also puts a constant 75 amp load on the port alternator at this low rpm. I am at a loss on how to get these 2 alternators to combine their strength to charge the lithium bank and have some sort of heat regulation without the 2 battery banks connected. This system was done for safety so if the house battery is depleted to a point that it cannot start the Starboard engine, then the port engine and generator battery are isolated and still full to get the generator with charger running as well as the port engine. This would charge the Starboard engine battery in short order to facilitate a start. There must be way to accomplish this without spending thousands of dollars on larger externally regulated alternators along with who knows how many other components. The temp switch may be a partial solution as I think if the voltage sense wire is disconnected, this would shut down the output and at least protect that one alternator from frying again. Getting the other alternator involved would be a bonus. Any thought by you or anyone else out there?
Wow there is a lot going on here. I'm afraid your question deserves more time and analysis than I can give here. If you would like to drill into this design I'm confident we can come up with an inexpensive system to do what you want but it will take back and forth to really drill down to the requirements. Take a look at our Patreon "Dream Believers" tier. If that looks good to you, its the right place for this level of question. For short advice. I'd start by considering loosing the isolators and using a pair of these in stead th-cam.com/video/qckmr6MgQCs/w-d-xo.html They are cheap, and cause no voltage drop. Diodes were a great solution to this issue in the 70s but time has marched on.
Excellent words I now won't have to type either. Thanks. Some have played with varistors temperature compensated. A few sailors tired of the cost of the potted voodoo regulator went hardware simple despite being programers. I have a VSR daisy chain working well till more money. No heat at all. Your BMS in on my wishlist.
You made this more complicated. I have a lead battery as my starter battery and is using a dc-dc charger for my agm battery. I use this in a car setup. Please note i can use a lithium battery but too expensive for my needs. My agm is only used to power my fridge during a road trip and camping. I created a video on my channel about it and works like a charm.
Not really. Ask yourself this. What voltage do you set your dc-dc charger to? The more research you do the more you will realize there is no correct answer. You can't safely charge li to a voltage. Lithium requires a specific charging method that simply can't be met by those devices.
Yes I'm talking about lithium specific chargers of all types. They all charge to a voltage. What voltage?? It's different for every current being delivered to the li cells.
@Emily & Clark's Adventure The Renogy DC to DC charger can be set to 4 different voltages by setting the 5 "dip switches" to a predetermined configuration. 14V, 14.2V, 14.4V and/or 14.6V for Lifepo4. It also can be set to charge LA. 12.6V, 12.8V and/or 13.0V. I'm using the 14.4V (lifepo4) setting, which is widely recommended by many manufacturers of lithium batteries, including mine.
I know. I own one. I'm saying there is no right answer for every charging rate. If you charge at 20 amps one day there is a setting that's right. Then the next day you charge while there is a load, say your refrigerator is running at 7 amps. Now you are charging at 13 amps and you need to stop the charge cycle at a lower voltage. There is no one voltage that doesn't cause low current overcharge. This causes irreparable damage to the cells. Also repeatedly not charging to full causes memory.
I just picked up 2 100A Eco worthy lithium batts and likely won't be long before wanting a BM regulator from you Clark! In the meantime I might do a little DC to DC charging experimentation.
Careful with overcharging if you charge slowly I'd set the charge limit to something like 13.8v and have it float to 13.3 right away after it hits 13.8v
A decent alternator's regulator will catch the disconnect before the spike and disconnect the winding in the alternator. I've jumped cars with no battery in them MANY times wity a jumper pack, and then pulled the jumper pack off once it was running, and I've never blown alternator diodes. I have seen a slight spike in the brightening of the under hood light, but that was it. I'm guessing the load that a car draws is larger than a boat possibly, and doesn't cause a huge spike.
Hello my name is James Mason and I live full-time in my 1967 GM TDH-4519 new look city transit bus, it has a Detroit Diesel 6v71n with the Delco Remy Dn-50 gear driven oil cooled brushless 12 volt 225 amp generator but I plan on replacing it with a 450 amp version, i would like to get a Wakespeed ws500 controller but i don't know if it will work with a dc generator. I plan on having one 1000 ah lithium iron fosphate battery bank using 520 Headway 38120 hp 8ah cells for both house loads and starting the engine. What would you recommend?
I don't know much about modern generators. The last car I had with one was a 1955. I'm really surprised you aren't using an alternator. Maybe it's a bus thing. That's a lot of headway cells. Like 500. Those things aren't cheap. Why not go with big prismatic cells? And a BankManager of course.
@@Clarks-Adventure the reason I am going with the headway 38120 HP cells is because they put out enough current to start my bus and they are cheap, about 200 USD for 48 cells. I forgot to mention that I will be using a Rec 500 amp bms that also controls contactors for input and output and that both the Wakespeed ws500 and the Rec bms will be connected and controlled by a Victron cerbo GX
Great info, thank you. I have a Hi-bred Bp Chassis + LiFeP04 House. Morning is the high load 35A if the load goes over 35A the current to the LiFeP04 is chopped (not by the BMS). I don't know what is cutting the power. Any suggestion? 1993 Commons Diesel powered Motor-home. Have you looked into Starlink "Flat Mount"? I have, Looks Great. If you buy a Land Based, it can be Up and Down graded for Marine Service.
I don't recommend that. The major reason I developed the BankManager approach to a hybrid battery system was to use each battery chemistry to its strongest advantages. With all lithium you loose the passive alternator protection and honestly the cheap easily replaceable starter battery (I bet that li starter cost a mint!) As well as a reliable battery system to fall back on. We went into all that pretty deeply in the document the ISO asked us to write docs.google.com/document/d/1a5M0V9JjaMezCZjJwrGv0IhCekAy-r_X6PPKs1YG8dY/edit?usp=sharing If I were you I'd use a lead starter battery. Something like this. th-cam.com/video/Xp6ssk4Guuc/w-d-xo.html
4:29 would the voltage spike happen in an automobile with a lead acid battery if you disconnect the battery while the car is running? I’ve seen people do this to check to see if the alternator and after learning about lithium I’m wondering if that has been a problem over all these years?
It really could but seldom does in cars because of all the many electrical loads a modern car has. These loads provide a path for the power being produced to flow through. Boats operate most of the time without an engine running so they have few constant loads.
Good point about loss of battery load killing alternator, especially on diesel with no engine electical load. How about simply keeping the alternator / regulator always lightly loaded with a couple of engine comparment light bulbs?
Our RV (Pleasure-Way) uses the factory Mercedes Sprinter 200 amp alternator connected directly to 2 100AH Lithium batteries via a timed switched solenoid. The amps range between 90 and 130. It seems to function well.
I’ve always asked myself if a blackout was possible when BMS disconnects.. wasn’t sure if it only disconnected from incoming power or disconnected the whole thing.. now is clear.. doesn’t sound good to electronics and a little annoying..
Thanks for discussing this! But why so hard on DC-DC Converters? Yes it's another green or blue box but I installed one it works flawlesly and doesn't need a lot of attention, you can easily adjust on charging profile, set voltage, amps, duration so it can nicely work together with what you already have. No need to fiddle with alternators, easy install and not more expensive than alternator and regulator upgrades. Very easy to live with last 2 seasons, and solves both issues you rightly brought up here! While Lithium takes a charge so easy you hardly have to max out on alternator power, In parctice I rarely draw more amps than 1/4 of the rated alternator output (115A), most of the times its set to 25A.
I have used dc-dc chargers. Sometimes they are a good solution but usually they aren't. My issues: They are mono-directional. Can't move solar power to the start battery. They waste power (minor issue with power to heat but major issue since they can't pass much power. As you said seldom 1/4 of the power available. They don't charge li correctly. They charge to voltage not to full. See my recent video on the BankManager for a definition of low current overcharge. They are basically unnecessary. Hybrid batteries are better if managed property. But we are all captains of our own ships and should do as we wish.
@@Clarks-Adventure true, all choices are personal, only wanted to add my positive experience here.. to react to your points: I connected the solar power to a Blue Sea 1-2switch (after the solar charger) to choose banks manually. When not aboard it is switched to the lead acid starterbattery. The DC-DC Charger can be set to stop charging the Lithiumbattery ones Tail-current thresholds are reached, in combination with the apllied voltage (eg 14,0 Volt at the Li-battery), just like the solar charger or the shorepower charger (all monofunctional on purpose). I am least worried sofar on the efficiency of the setup, more to (losing) simplicity and how to save or enhance some sort of redundancy. I am very interested in your creative solutions and will sure look into the benefits. Many thanks for your time and efforts!
Which dc-dc are you using? I've only tried the renergy. Be careful with the battery combiner switch. If your lead is quite discharged li can try to send LOTS of current into it. We have seen some smoking wires during tests.
@@Clarks-Adventure I installed the Mastervolt MacPlus 12/12-50 2 years ago, as part of a total overhaul of the electrical system. Can also act as a stabilized (max 50A) DC-source, so if Lithium is down engine can be used as generator (for basics: nav, autopilot, lights etc, not microwave). This Blue Sea switch has deliberately no combiner function, it is in to be able to maintain control over the solar charging.
First, you never never tie an alternator to a lithium battery. A LiPo will draw as much current the alternator can supply. A DC-DC converter is needed which has current limit capabilities. This setup has been in my Van for about 2yrs. 3-100@hr batt's. Works great!
@@Clarks-Adventure I did, I must have missed why this is wrong. My setup can never draw more than 40 of 160, and the alternator is never hot. The cells balance evenly. What did I miss?
Seems like your alternator doesn't have overheating issues. Many don't. I'm not sure why you are only getting 40 amps out, you might want to look into this. The bigger problem is what happens to your alternator diodes when your Li BMS shuts down during charging. That's where the lead protects your alternator diodes.
@@Clarks-Adventure Its a 50 amp DC charger, but I've never seen it charge at more than 40 to 45. And that's with it hooked up on the solar side as well, but the switch off. So it lets the alternator charge at more than 25. Power going through it is supposed to be a one way thing with how it's set up but I'm gonna look into this more, thanks.
I'm personally not a big fan of dc-dc chargers. They do current control but there are cheaper, more reliable, ways to derate your alternator and of course they don't know how to properly charge lithium even if they have a Li setting.
I know you are talking about a boat system what about 12v lithium car battery I've seen these as drop in replacement for car batteries and they come with built in car jumper feature in case the end user accidently drained the battery by leaving on some kind of accessory; headlights for an example, it could jump it's self. I know it's not a boat set up but how much different could a marketed car battery and alternator be from what's used in a boat other than voltage and amps ? I'm just asking because I thinking about getting one
@clark what you described with the blackout and then restart sure sounds like what happened to the Dalle container ship. Any chance there is a connection ?
Great video! I am new to lithium batteries. I had an AGM battery in my cargo trailer hooked up to the alternator from my tow vehicle so it would charge along with the tow vehicle's battery while driving. I recently bought a LiFePO4 100 AH battery for the cargo trailer because I want to put a solar charger on it, and it has a 100 amp BMS rating. Basically I had the cargo trailer AGM battery in parallel with the tow vehicle's lead acid battery for charging off the tow vehicle's alternator when driving. I have a couple of questions. #1 - Can I even put a LiFePO4 battery in parallel with a lead acid battery and charge off an alternator? #2 - If I can put the two batteries in parallel will the tow vehicle battery act as a shunt to prevent the voltage spike when the LiFePo4 BMS shuts off?
I have several videos on this topic . You can do it manually but it's best to use my BankManager if you want the best life from your batteries. I suggest you watch through my videos on the topic. Check out playlists.
Good stuff….I want to switch to a LIon battery on my Corvette. The car has a Holley EFI system with a Mechman hi amp alternator. The alternator is triggered via a programmable output from the EFI system. At this point I’m using an engine rpm setting to control output but if I set/configure voltage and temp limits (I have a temp sensor in the engine compartment next to the alternator) I should be able to “protect” it from these issues you touched on …correct? Again good stuff 👍
I wouldn't count on that setup being fast enough to react to the BMS going off. The voltage from the alternator goes up really fast. Digital software controlled systems have quite a lag. Are you trying to save weight? Maybe run without a BMS and balance the cells with an active cell balancer as described in another of my videos. Or maybe super capacitors?
@@Clarks-Adventure I just realized the battery Im considering is a Lithium Iron Full Spectrum unit with no BMS …..May be a different scenario than what you are referring to in the video ….Thanks for the reply 👍
Question: if you are running Lithium for the house and Lead for the engine that are connected to a magneto (modern outboard engine) do the overheating concerns still apply? Given the continuous running nature of a Magneto do we just let the BMS do it’s job to regulate amp charging of the Lithium batteries ? Or do we still need a bank manager or dc-to-dc charger?
You still want the BankManager as the voltage regulator in the outboard wouldn't treat the li kindly. I just don't have any experience with what happens when you remove a battery from a modern outboard so the diode protection may be unnecessary but the li charge controlled is very important.
Someone suggested a potential problem with this. He might be right. Adding a flyback diode might help protect the switch for longer life. I'll talk about it in the description of the next video. Too late to film anything.
@@Clarks-Adventure I'm looking forward to it. I recently upgraded to 200Ah of Lithium (27' sailboat) and I've been a little worried about how the rest of the system.
I just updated the description of this video to talk about it. I basically said check wikki. What I really should have talked about in the video was venting the engine room. I think I'll add that to the description now.
I enjoyed this video. The idea I had when you were talking about using the lead battery to protect the alternator when the lithium battery opens it’s circuit and stops charging was, would one of those super sized capacitors used in audio amp installation work in place of the lead battery? The capacitors I’m talking about are over 1 farad and some even have digital voltage displays built in. Capacitors life generally lasts longer than lead batteries. Just a thought. Thanks for the interesting video. This is the first time I’ve seen your channel.
Technically it would solve the problem nicely. But,, it creates so many problems of its own. It's hard to control current with one of these. Its charge acceptance ability is scary.
Electrician here: The voltage spike from open circuiting a large 12 volt alternator under max load can exceed 1k volts. This is why a TVSP device will help protect the alternator and all of the electronics in such events if you have a battery disconnect switch of any sort, including the BMS. If not using a lead acid battery in parallel, I would go with an adjustable external regulator that will connect to the BMS of the battery to regulate both current and voltage to provide optimal charging within the required range of the lithium battery. One can even set the output voltage of the alternator regulator slightly below that of the PV array charge controller settings so that the array will be prioritized over the alternator, plus the output of the alternator can be controlled to allow for de-rating if overheating is occurring. I believe that there are now can-bus controlled alternator regulators that will integrate with the entire system. Those lithium iron batteries are a big investment, and one will want to get the longest life out of them. The heat created by the alternator is a function of the winding resistance, the power output/field strength, the alternators cooling fan, and the temperature and volume of airflow in the engine compartment. The reason we use alternators over generators is that they have the ability to provide a fairly large output even at low RPMs by increasing the strength of the field windings, creating more current flow in the windings, thus more heat while the alternator fan and the engine fan are operating at low levels, thus causing more heat buildup under slow RPMs. Normally this is not an issue in running basic electronics and keeping the starter battery topped off, as the alternator will just be idling well under its rated maximum output. But add a load like a lithium battery capable of keeping the alternator at max output continuously, and that can really stress the alternator. One can help overcome this by using the above mentioned regulator, and by also using electrically operated and thermostatically controlled fans to cool the engine compartment, along with de-rating a larger alternator. A 100Amp alternator will have 1/2 the winding resistance of a 50Amp alternator, and will run much cooler when outputting 50Amps than the 50Amp alternator running at its maximum output.
Would a further option be to add an invertor as the load on the alternator and to feed that into the existing smart charger? Kinda like a DC to DC convertor but employing the existing smart charger. (Note: i charge my batteries from a stand alone gen set, by feeding the smart charger).
That seems really unnecessary and a huge waste of energy. The hybrid battery approach with a BankManager gives many many advantages including proper charging of your Li bank for much longer life.
@EmilyAndClark Can you explain why you consider it a waste of energy? Inverters have an efficiency of 85% plus and so do smart chargers. Moreover, if I am only charging this way when the engine is running, the increase in diesel fuel consumption is marginal. Isn't the issue more a question of whether the smart charger will accept an imperfect sine wave (although mine accepts the output of a Gen set), cost and space (would need a 40 to 50 A Inverter). Not keen on the alternator being dedicated to a (lead acid) start battery as would have to reconfigure or remove the combiner arrangement.
You can do it anyway you like. I suggest this approach. www.emilyandclarksadventure.com/bbms Sure it's like 20 percent heat waste TWICE. If that doesn't bother you go for it. I'm not going to engineer your system in a direction I don't believe in. My approach has a lot of advantages but if you only concentrate that it's the only way to charge li correctly for a long life that should be enough. It's just extra points that it is a simpler more robust approach.
@@Clarks-Adventure Clark, I think he is just saying that he has a system setup as he notes and it is working out really well - thats all. I dont think he was posing any sort of question at you.
Most BMS only disconnect charge. So if the BMS disconnects and destroys the alternator the power doesn’t go out as the the battery discharge mosfet is still turned on. A big alternator will produce less heat for a given amount of power owing to its lower internal resistance. Another method that works is to find the continuous happy current of the alternator and you then extend the charging cable to add enough resistance to reduce the current. F have a 14.2v Alternator then you subtract the lithium voltage it spends most of its time charging at which is around 13.6v so you just need to drop 0.6v at your chosen amps. Many systems already drop this anyway but it generally doesn’t need much extra cable. An advantage to this method is that it also produces a short current taper towards the end of charge which is what the cells like. This is one place where resistance in the charge circuit works to your advantage using the very flat charge curve of lithium in order to work. I can now say from my own feedback that dozens have used this method in hybrid systems to good effect. So long as the correct cable is used that can safely carry the max output of the alternator then no rules are broken. I too believe that DC-DC chargers in this situation are the spawn of Satan. I’ve just scribbled the software and built the hardware for a regulator that can measure voltage, current and temperature and regulate based on all 3, I only did it as I got a 180A smart alternator for £20 where the internal regulator is useless as it’s controlled by the car management system and so had to be bypassed anyway. It’s really stupidly easy and cheap and has wifi monitoring and setup.
any plans to do 48V. i have a NiFe battery comprised of 36 600ah cells i had to put this in a shed do to hydrogen off gassing. i interested in expanding with Lithium LiFePo4 but have been looking for a way to get them to play nice. this looks promising but i could only find 36V version
This content is great! Thanks! What is the minimum size Watt hour lead acid “shunt” battery required when using lithium batteries? Just installed a Mechman 400 amp alternator that can handle 250F+. This will feed a 4000watt inverter installed in F250 truck crew cab to charge my electric motorcycle. Ordered a 16 Amp NC. Temperature switch. Will also use a fly back diode. Might get another one to monitor the starter batteries for the inverter temp sense input. Exciting stuff 😅
Lead size with a BankManager is all about what's required to keep your charging system "sane" when the li is disconnected. Some systems require more than others Starter type batteries work best but they should seldom be power cycles of course
@@Clarks-Adventurejust looking for the formula to calculate the lead acid battery size needed to shunt the back EMF generated by alternator when the BMS disconnects the 140 amp hour Lithium battery. For example . Will a 1 amp hour lead acid battery work?
If you let the BMS shut down your Li damage is happening to that li. Use a BankManager. BMSs aren't battery charging devices. They are for emergency situations Usually a car starter battery works
Personally I like the idea of regulating my power input from alternator to LiPO, even if it cost me a little power. It will extend the life of your alternator and battery if you have a well matched system. No need for lead batteries, could even use capacitors to start your engine.
You can't use capacitors, they can deliver an insane amount of amps for only a very short time, and then they present a total dead short to the charging system... As far as "regulating" the power input from alternator to the LiPO, all you need is a battery that has an actual 'intelligent' BMS system, or just get a battery from a good brand like Victron energy. You get what you pay for.
@@brnmcc01 done this 10 years ago on my beater car, no issues just looses charge after a few weeks but if you can recharge at will not an issue. What do you think solid state batteries are?? Victron is expensive and you can do the same circuits yourself at least that way you will have knowledge and recourse when it brakes down ! If you gonna try this today just be careful with your circuit protection, new stuff is uber sensitive to intermittent voltages, like you can fry some components especially memory.
@brnmcc01 Bombardier uses a capacitor to start small 2 stroke engines currently in production. I don't know enough to know how that scales, but it does exist.
I have a small outboard and want to charge my new LIPO4 battery from the outboard. The 5 amp alternator is built in to the outboard. Do I have the same risk of blowing Diodes if the BMS turns off the LIPO4 battery? I don't have a starting battery since the outboard is pull start. Do I still need to add an AGM to protect the LIPO4? Can the AGM be a motorcycle battery, (~20 AH)?
You won't hurt the outboard alternator because it's designed to operate safely with no battery attached at all. But your alternator will charge your Li like lead. If you never charge the li fully no problem but if it fully charged the outboard will be the absolute poster child for "low current overcharge" which kills LiFePO4
What about this scenario: In a vehicle, using a LiFePo battery as an aux battery, installed with a battery isolator? The alternator would charge the lithium aux batt, and the lead acid starting battery, and would always have "something to do" w/ regard to charging and operating the vehicles systems as it did prior to putting in the auxiliary lithium batt. Am I missing something? I'd like to add an aux batt to my truck, and lithium sure is appealing! Thank you! (edit: for context, the aux batt is only for running a portable refrigerator that runs at 60 or 45 watts, depending on Eco mode selection ... so I'm not trying to power heavy equipment)
From the alternators point of view no big issues assuming it's continuous duty. From the li batteries view. Yuck. It's going to be cooked being charged like a starter battery in a car. 1 to two years life, tops. You should use this instead of the isolator. www.emilyandclarksadventure.com/bbms It will control the charge to the li
Very informative. I bought a NOCO lithium battery for my motorcycle. Is this scenario possible? What remedies can I use if that's the case? BZY91C18 diode?
I dropped a little Li into my bike years ago. My bike has a 1.7 liter engine and the lead batteries just didn't last long or reliably crank it over. I've had no problems but I certainly wouldn't need 15 years out of it to feel I got my money's worth. Honestly I'm not even sure it's a LiFePO4. So what I'm saying is those are different little beasts. They live hard and I bet they will die young but in the scheme of things don't cost much. The banks of li I'm referring to in my videos cost a lot more and, in the boat case, are taken to places where replacement is nearly impossible. They have to be reliable.
How about the Epoch Dual purpose 12v 120Ah cranking, deep cycle battery? Would they work ok with a Boat alternator? How about swapping a 12v RV battery with the dual purpose Epoch battery? Would I need to change my inverter?
No regular engine alternator should ever be connected to any BMS enabled Li battery. Outboard alternators trade efficiency for protection from battery removal. The best way by far is the BankManager hybrid system. Besides its ability to protect components connected to the batteries it is the only charge algorithm out there that doesn't damage Li by low current overcharging. marinedcac.com/pages/bankmanager
How about Lithium replacement in lights duty diesel truck? Replace the main battery with Lithium and keep the second as Lead to keep the alternator happy? Still need the Bank Manager?
If I have my lead acid starter battery connected to the alternator and completely separate from the lithium house bank and solar panels, is there any disadvantage to this other than being unable to charge the house bank with the alternator or use the starter battery as a backup house battery? If I go with this setup, what typebof syarter battery would you recommend? I understand that your videos and other resources should make this all clear on their own, but it's a lot to take in. Thanks!
Not anyway near as much work as making them was for me Put the effort in. If not on my channel elsewhere. And once you understand the situation you will find you want a BankManager. It's the only way to do it all right. But you have to learn for yourself or just buy my product out of blind trust.
Hi Clark I’m just watching one of your videos and you mentioned fitting a Lithium battery into a standard AGM battery Box , I have a Projecta power hub Battery box which has a 300 W inverter built in , and built in BMS , ot says a lithium battery can not be installed, is there a way round this as I like the Box , Thanks Clark Keep the great Videos coming 👍
It boils down to how the li is charged. And I assume your current device doesn't have a BMS but a charge controller. BMS is a li thing. I'll likely do that video eventually. If you are good at reading between the lines take a look at this. th-cam.com/video/odhuEauAvLU/w-d-xo.html You will see me charging that Redodo with my BankManager as a charge controller. I assume you either charge this "box" or use it. This can be done. But it would be DIY
I have a lead starter and 2 AGM house batteries commected by Yandina battery combiner. My alternator is connected to my lead starter and the Yandinas feed the AGMs. I wonder if the Yandina would save ny alternator when I switch my house batteries to Lithiums...
Hi Clark, Rick Moore from Sophisticated Lady Explained the installation of a second 48V 5kW Balmar alternator, with individual Balmar regulators per alternator and a centre fielder to sync the alternators. The output of the alternators connect to a common buss with a feed to the 48V LiFePO4 battery system. So I don't know what happens to the alternators when the batteries get fully charged? His YT video SSL667
My toyota hybrid does not have an alternator, Will a lithium battery instead of the 12V lead acid battery hirt the 12V charging system in the phase converter?
I'm assuming you mean one controlled by a BankManager. The BankManager doesn't cart but you need enough lead so things stay sane with your charge controllers after the BankManager disconnects the li. Generally as long as you aren't using a cheap Chinese inverter/solar controllers with many kw of panels most anything works for lead
I have seen a lot of gear that says it is for charging li. But I've found flaws in all of it except for constant current chargers that plug into the wall and only charge li that is not in service. Well except for the BankManager. I of course haven't seen every offering, no one has. But one gets tired of looking. But I just realized you are likely talking about alternator regulators that shut down on a signal from the li BMS. Sure that works. I mention it in the video. Works but expensive.
@@Clarks-Adventure Thanks for your reply! Here is a video by The Fit RV that goes over many details about the CAN alternators - th-cam.com/video/sSYoi7_t640/w-d-xo.html
I watched the video. Thanks. I can't tell what logic the BMS is using to request a charge but if it's correct (that's not a given) this should work fine. My issue with this approach is you need to use batteries with a special BMS (read extra expensive) and change all your charge controllers to canbus units (also extra expensive). That's all of them. Solar, alternator, mains chargers, wind... I designed my system to work with any regulators that work for lead. And you can spend your money on more Lifepo4 cells. and of course I trust my devices ability to know when the li under its control is exactly fully charged. The BMS might be doing that well but let's just say it was a difficult problem to solve.
@@Clarks-Adventure Excellent. Right it's a matter of cost difference and also being a different implementation. Thanks for watching that and giving your insights and comparing it to your solution presented here! I see you do have a truck camper as well and I watched that tour video by Emily a few weeks ago not knowing this is the same channel. Keep the spirit!!
I'll be doing some testing with that truck once we get back to the US next week. A overland RV company is having trouble getting modern trucks to charge external batteries. I happen to have one of these modern trucks so I'm going to hack the charging system. You wouldn't have any insights into it would you?
This may explain a similar problem I'm having. I recently replaced both batteries in my wife's BMW. One was toast, the other, 5 years old, but still working fine. It's worth noting that these two batteries look and feel like a regular car battery, except they are $350 each. Something about the battery having a BMS made them so pricey. About the same time, I bought an old boat and needed a battery for it, so I just used the BMW battery. After a few months, the alternator on the boat started putting out 18-20V. It was the original alternator from 1995, so I replaced it without much thought. A couple months later, now my new alternator is also outputting a 17-19v. I'm starting to think the BMW battery is killing the alternator voltage controller.
Batteries with a BMS can just turn off. Alternators hate when you remove their battery. All your other electronics hate when alternators have a bad day.
So I want to deck out my electric system in my Catalina 22. The goal is to do the Texas 200 comfortably. But is ac, inverter and lithium to much for such a small boat such as mine?
What about using that temperature switch to disconnect the LFP bank from the LEAD starter battery? Just a solenoid or relay. Those bimetallic temp switches are cheap - just glue 2-3 100C in series around the alternator housing - if any of them trips - the alternator has only to supply the regular operations.
If the li is hungry and you disconnect it but charge up the lead reconnecting can be dangerous due to the low internal resistance of the li. There can be quite a current surge. In real practice with a good well protected installation I'm sure it would work. I like how you are thinking.
@@Clarks-Adventure I can see that case happening. True. How do we reduce that inrush current? Adding some variable resistance? What about adding a longer wire? The voltage drop is proportional to amps flowing when I remember correctly. Used to study electrical engineering, but went into a different field after a while 😉 I like those kind of puzzles.
I have a Yanmar 56hp diesel which I think has an 80amp alternator. My starter battery is two 6V deep cycles in series for 12V. I have a victron 18amp DC/DC converter fed from alternator to two 12V 206ahr SOK LiFePO4 batteries. I like the idea of the thermal switch and having spare diodes on board. Any advice or critique here? BTW, really love the way you explain things. I am a retired chemist and typically chemists and engineers don't see eye to eye. My eyes , and ears, are wide open. Thanks Captain Qwiksword SV Gratitude Cocoa Fl.
thinking of parallel connection (pbo2 & lifepo4), alternator connected only to pbo2, hopefully balance-charging changes the lifepo4 battery too :). thanks for bringing this to our attention :).
I'm a highly accomplished electronic engineer in several things including power management systems and devices used in alternators and battery management systems. I passed by your video thinking "what is this non sense". I was quite surprised to find that you are quite technically correct in this video. Excellent job.
It's the years experience that sometimes counts more than the Qualifications 😁.
why not just run a 4x4 relay dual battery VSR? if the bms cuts out the lead acid battery will still be there.
Because the lithium gets mischarged by the alternator.
@@Clarks-Adventure mischarged how? "Lithium Ion batteries are charged with an absorption voltage of 14.25 V"
They shouldn't be.
I suggest you read Conrad's writeup linked to the bottom of this.
www.emilyandclarksadventure.com/bbms
I remember when alternators first come out I was working for the Ford company on the coast of Mississippi. They sent us to auto school in New Orleans and they explain the function of the alternator they were going to replace the generator on cars and they replace them were the last cars, we had that had generators 1960 alternators took their place the fields turned inside the armature right reversed to what a generator did and you had to have 1 1/2 volt to excite them to make them work. If you had a dead battery you could push that car all day long and it would never generate any power that was a long time ago we have come along way now with electronics . Grate job Clark as always
Thanks
Many times the residual magnetism left in the alternator is enough to get it to kick off and start charging.
And people mistakenly think batteries and charging systems are simple and don't understand why I think they aren't. This post and the following comments/discussion support my contention. I rarely read comments, but I took probably an hour or more to go through these. Very informative and time well spent....👍👍
Yes
Everything is simple until you understand it.
@@Clarks-Adventureexcept the opposite is true with electronics and wiring!
Thanks for the great breakdown, Clark! I'm a marine electrician and have hesitated to do lithium installs on my customers' boats because of the off chance that a BMS opens the circuit, frying the alternator and everything else. I REALLY like that the lead battery is there as a guardian.... and now with ways to thermally protect even internally regulated alternators I'm even more excited. I'm currently cruising, but will be back to work in a few months. I look forward to the next video and the possibility of installing a bank manager. Thanks again for the great video and sharing your knowledge!
No chance that a soft start 50A BMS can fry the alternator when a 90A compressor, or a 200A winch with ugly back emf, doesnt. The starter battery has very low impedence and is the voltage clamp, in much the same way as a giant zener diode
@maya. Have you gotten back yet? Did you find an opportunity to do a BankManager install?
would a flyback diode work with the lithium battery BMS shutting down?
@@darrellobrien4416 nope. It's not a reversed colapsing field. It's just the alternator making full power. Forward and too strong for a diode anyway.
@EmilyAndClark almost had a customer convinced to get a lithium bank and keep the existing lead acid. They didn't go for it though...
The way the author of this channel explains and teaches reminds me of my enthusiasm for science as a youngster in class (late 70s-early 80s). I’ve had deafness since birth, and what little I could understand verbally was supplemented by visuals in the classroom. The author has many of the qualities of those teachers I admire and I appreciate that very much. Thank you so much. As an adult, with my deafness, TH-cam, with its closed captioning, has made the educational aspects much more accessible thank goodness.
With the help of YT, I’m attempting to design & build a 100ah lipo battery system for my truck with limited space. I’ve purchased a Renogy 12V 30A DC to DC Charger with MPPT, On-Board Battery Charger. At the moment, after learning from this video, It’s clear that I need a system that is plug and play. I don’t have the capacity to understand all the science at play here. I use my truck daily as part of my job doing outreach and reliability and safety is my utmost concern. As well as affordability, which is why I’m trying to design and build it myself. I just wish there was a complete system I could install myself with more confidence in those goals. Any suggestions? Thanks for “hearing” me explain my situation in advance. Kind regards.
You might find this useful.
www.emilyandclarksadventure.com/bbms
Thanks Clark. I'm finding you far more straightforward and informative than the battery manufacturers.
Q: If I go either the dc-dc or Battery Bank route, d o I need to install a monitor or alarm/fuseto let me know if it fails? Or, is my first indication smoked alt
diodes.
I sent an inquiry to LiTime, asking if they are recommending any sort of dc regulator. So far, no response. And I'm finding lithium battery ads pushing their products as "drop in replacements" for lead acid batteries.
The alternator is a convenient back-up for cloudy days, so I would really like to retain it as a charging source. However, I've just done an alternator replacement. It was not fun, easy, or cheap, and I'm not looking forward to doing it again soon.
Thanks again for this video. It's a valuable service for any of us who go lithium! 4:56
Li is nowhere close to a drop in replacement for Pb. Even the li charger controllers available today don't charge it right for a long life.
To keep your alternator cool the best solution is an external regulator with a temperature sensor. I've always used Balmar. People I respect like Sterling.
BankManager and some lead will keep your alternator's diodes safe and charge your Li property for a long life. (So there's my commercial. ) www.emilyandclarksadventure.com/bbms
I'm not a fan of DCDC chargers. I think I go into it in the FAQs in the link above
Excellent! I use a DC DC converter from 12v to 24v since my house battery is 24v, but I never thought of a thermal switch as a protection. Very simple and cheap :-)
Great video, valuable info with minor amount of self-promotion. I see so many people switching to the external regulator alternators at great cost.
Great information as usual. Your deep understanding of electrical engineering and excellent explanations are what make your technical videos so great. Often other channels, even when providing technical details, are just repeating what they were told by equipment manufacturers. Which is not all bad or wrong, just sometimes not quite all the details that we really need to understand all the issues and make the best decisions. I am looking forward to the alternator tear down. I have often seen people say that you should basically throw away an alternator if you blow the diodes and that has always seemed like it shouldn't be that hard to fix. Thanks for all the great videos. I don't even own a boat yet and may not for several more years, but I'm tempted to buy a BBMS just in case you quit making them. So please give advanced notice if you every decide to quit. But hopefully you will be hugely successful with it and keep making them.
So nice of you to say Jim.
As for fixing alternators, that could be true based on the cost of US labor. And because of that culture parts are hard to find.
Go someplace like the DR or Mexico and everything is fixed. So parts are readily available.
@@Clarks-Adventure The Alternator parts are all pretty easy to find, at least here in the area around Tampa Bay. Alternator Starter Parts Wholesale in Port Richey Florida is a great resource for (as you might have guessed) alternator and starter parts since the owner is quite passionate about not only having the parts but also the quality of the parts. They recently got me an American Made higher quality long nose starter drive than most put into a rebuilt Marine 454 inboard and got it overnight for pickup at no additional charge. Had a nice motorcycle ride on a beautiful Florida day when I went to pick it up and was able to look a person in the eye and shake a hand. Hopefully his son will continue running the enterprise when he retires.
How many folks throw out small appliances just because its cheaper to say replace a $125 portable ice maker because it costs too much to pay someone to put 3 drops of sewing machine oil on the bearings of the computer fan that was used on the condenser. We often don't think of the cost of waste on the environment when we do that and only look at the Dollars and Cents or whatever currency you dealing with.
I just fixed a small appliance by taking the 15 minutes to oil the computer fan inside it instead of throwing it away and dropping $125 on a new one. That was like getting paid at a $500 an hour payrate for 15 minutes of work plus it took less time than it would have to purchase a replacement, unbox it, etc, etc along with dispose of the old one.
Perhaps we should have a moment of silence for the demise of all the Emmet's and their Fix-It Shops (remember Mayberry) across the country who've fallen victim to the disposable culture we live in.
Keep up the good work but don't keep working so hard at it that you don't have enough time to pause and do the simple things like comb your hair. ;>
I technically gave you three likes on this one but the counter sadly only accepted the first one.
Best!!!
We’ve been binge watching your content lately. I love the idea of a Lead/Lithium hybrid bank and it looks like you did a great job on your BBMS product. I’m looking forward to this upgrade soon!
In just editing an endorsement video from a buyer now. So fun to see how much people like this. I think I'll release it as this week's video. He put it in a really big system.
For protection from sudden BMS shutdown, why not use a zener diode shunt? A zener diode is non-conductive until the threshold voltage is reached. Then it becomes a near open circuit. If you were to put a zener between the positive and negative charge wires, the voltage spike would be limited. Since the voltage spike would only last a few hundred milliseconds, the zener would be able to dissipate the excess energy with no problem. The alternator regulator will respond and bring the voltage back to normal and the zener shunt will turn off. I did a quick search and found 50W 50V and a 50W 35V zener diodes for around $10.
I've tried a zener in the past. It blew like a fuse.
I don't remember the specs. Maybe there are better ones now.
It's going to have to dissipate 35vx140a, that's like 5kw. That's a lot of power. The time wouldn't be the 400ms. That's how long before the alternator diodes fry and the zener it trying to protect those. It's going to be until the regulator shuts down and then the time it takes for the rotor field to dissipate.
If you run the test tell me how it goes. I don't want to risk my alternator.
An alternator under full load can be putting out 200+A for a few ms after the load disappears, your 50W zener will be taking 2000+W during that time. You need something more robust to take the spike. A 15V zener driving the gates of a dozen 250W MOSFETs to spread the heat and 5W 0.1 ohm balance resistors between each source and negative rail might work for clamping surges to about 18V. (15V zener + 10A x 0.1 ohm + 2V of gate drive for logic-compatible FETs = 18V)
Since the name of the game is slowing down the voltage spike so the regulator can react before voltage gets out of hand, a 500 000uF 25V capacitor bank could also do the trick.
You could probably put a super capacitor across the alternator to absorb the spike.
@@DrJuan-ev8lu I thought about that but wouldn't that make it worse because even if you had a super cap rated for that kind of voltage (100+v spike) it would dump it right back into the battery once the BMS came back online potentially damaging the battery. I suppose the argument would be that it couldn't absorb that much voltage in that timeframe but you'd have to have a bank rated to well over 100v and protection circuits would be vulnerable.
@@fatillacing4131 You can sink the excess voltage with a TVS Diode. If voltage spike goes high enough a varistor will likely have adequate joule capacity
Your content and presentation is excellent. In the upper threshold of TH-cam influencers that I've watched over many years. I hope you keep up the good work and are taking care of financially for it
Love this, thank you Clark! I've learned so much from you. Hope you and Emily are well and I'm so glad you're back on the boat.
Thanks Paul
The service manager at the marine mechanic facility I use just talked me out of using a lifepo4 battery for my starting motor. He was worried about how the charging system would be affected on my mercury pro xs. Told me to stick with agm and that’s exactly what I plan to do. Nice video. Very informative.
I agree. Use lead for starting.
If you want to add more battery you can add li in parallel with a BankManager
@Clarks-Adventure didn't even know they made lithium batteries for starters, I've only seen guys using supercapacitors for start an engine.
I've got the ecoflow system so I use their alternator charger to charge my 3.7 KW battery.
I'm currently filming a liTime 140ah battery that can start big outboards. I've already started my friends 115hp 4 stroke
It looks like an interesting battery.
Video coming
I love the content you guys are creating. Watched a ton and I feel I’ve learned so much. I currently liveaboard but I’m new to this life. Being a construction worker I’m financially challenged but very handy. With this information I’ve been able to enter a new way of life with confidence. Thank you so very much for all the knowledge I’ve gleaned from your content. So badly want a bank manager for my Pearson 40’s solar system and I’m starting from scratch. ❤
I have a few black box 1.x units.
Same electronics and software but $100 off
@@Clarks-Adventure that’s good to know because function is my only concern. Soon as the budget allows thanks
Your flat (most times installed serpentine) belt also has substantially more surface area compared to a typical "V-Belt" so it wears out much more slowly. Also, a flat belt usually has a spring tensioned self-adjusting pulley that is easy to adjust tension for belt removal and replacement unlike a fixed position pulley on V-Belts which require more tools and frequent adjustment.
So much better!!
@@Clarks-Adventure Not always I have pulled down many engines and found that the amount of tension applied by serpentine belts shows wear on the front upper main bearing shell at about 11 o clock which shows they often have too much tension applied in the design stage, So not everything is all apples in every case
I use the Sterling Alternator Protection device $80 bucks specifically made for an alternator dump.
Worked in power when many were new. This is also a great video for anyone thinking of building an off grid hybrid solar/mechanical system.
Thanks
I have motorhome with lead starting batteries and lithium house batteries. When the engine is running, the Alternator charges both systems. This means the lead batteries are there when the lithiums turn off at full charge, and the Alternator is protected from damage.
When the ignition is turned off, the lead batteries are completely isolated, they will not charge with shore power or solar panels. But there is also no power draw, so they can sit idle for weeks at a time.
When the ignition is turned off, the 2 battery banks are cemetery isolated.
An issue you should consider is with the engine running your Li is being charged like lead (not good) and then floated at voltage over 13.48 (really not good).
Are you considering a change?
@@Clarks-Adventure I thought you were giving me a green light for my motor home to have a lithium house battery. Now you are talking contrary with this response. I'm left confused once again.?? So I still won't buy a lithium battery for the house side of the motor home. And I thought lithium was to be charged at 14.4 to 14.6 volts to 100%. state of charge 13.6 volts. If I am charging and floating like a lead acid battery, how would the lithium battery ever get to full charge to shut down the BMT and destroy the alternator if no lead acid battery were present?
That was in a very old video. I have learned a lot since then.
That's why I developed the BankManager
@@Clarks-Adventure It was posted two months ago. OLD?? remove this video!
What video are you referring to?
More solid content, well organized. I'm definitely sold on the Bank Manager....but I don't have any lithium yet, so that order will be awhile coming. Cheers.
Clark, your tutorials are always full of great information. Emily help with mad scientist look. We all know he isn't mad.
From the title, I thought it's just another vid about bank manager, but its so much more.
Looking forward to the tear down.
Thanks Lana
Great idea with the thermally operated switch to control the alternator. Will store that one away for future use. 🙂
These thermal switches are so cheap, I don't understand why all motors and alternators aren't thermally protected. I once burned out a Makita planer just planing some hardwood. You spend all that money on a power tool and they can't put thermal protection on the motor?
Great Lithium topic. If you have a Balmar with an expensive external voltage regulator, you can rig a switch that allows 50% output. You can run in 50% mode by default unless you want to "fast charge". Fast charging is used on exception and prolongs the wear on the water pump pully on my Yanmar 3GM30f motor.
I think it's wonderful that you're helping people. Thanks Clark. :-)
Thanks Clark, now I have to figure out what kind of alternator I have. Keep the good stuff coming.
I have a few more ideas.
You can have a voltage sensitive relay that connects your lithium to your lead starting battery only when your alternator is charging the disconnects when lead battery voltage drops to its resting state. It won't matter if your lithium battery disconnects because your lead battery is still connected.
You can also upgrade the BMS in your lithium battery, my JK BMS turns off charging when battery is full but still allows discharge so there should be a voltage there for your alternator to see and not shoot up in voltage, that's what happens with my solar inverter.
You can also maybe have a decent capacitor in parallel with your battery to hold a voltage in case the BMS shuts off while the alternator is charging, in theory the alternator will sense the voltage in the capacitor and think its a fully charged battery.
You can also remove the regulator and diode assembly in the alternator and manually power the rotor field with your ignition or a switch and connect the 3 phase stator to a 3 phase bridge rectifier to get your high voltage dc and with a suitably rated capacitor to filter the DC then connect the high voltage dc to a solar regulators pv input to simulate solar panels. The charge controller will then handle all the charging to the lithium battery. I will be trying this to make use of a fried diesel inverter generator.
Great info about the overheating and thermal switch mod too.
nailed it a lead acid starter battery will take any voltage shook for an instant
My fix for this issue, tie in a supercapacitor in parallel to the battery.
Iv'e actually blown out two solar charge controllers and nearly took out my inverter over a very similar issue. Smoke and flames, glorious flames!
Many of the earlier LiFePO4 4 batteries had a lower cutoff voltage; right around 14.1 volts, the newer ones run around 14.6volts. Regardless, even if the BMS triggers, the cap provides enough cushion to allow the charging equipment to shut down safely.
the supercapacitor did 2 things for me, it fixed this issue, it also allowed me to start fairly heavy motors rated at nearly the inverter capacity without issue.
What size cap are you using?
50F, the sucker looks like a 6 pack
My concern with big cap banks is what happens when you get a short circuit someplace in your system.
Great video, Clark! I was about ready to go out and buy a DC to DC Charger when you told us that I didn't need one because I bought your Bank Manager.❤
Great info as always Clark! Happy to see I am not the only one with vbelts that goes to dust! I will do the upgrade.😊
I’m quite the opposite of the person below who stated they were highly trained and experienced in electrical systems. About all the training I have is enough to know sticking one’s tongue on a 9 volt battery or a fork in a 110v socket is definitely an experience I will remember for the rest of my life. To me electronics are similar to magic but what I will say sir is you definitely explained things in a way that even a caveman like me can understand. Thanks and I look forward to watching more of your videos.
✌🏽
Thanks,
Please consider sharing this video if you think your friends might also like it
Thank you for making this very insightful video and explaining things in a way that even The average person can understand! 👍💯
Glad to see you back on the boat.
Great video.... having the starter battery permanently connected to the alternator and hooking the lithium in parallel through a battery isolator solves the high volt issue, then with a long 10mm2 battery cable about 10 m long going to the lithium house battery gives enough resistance to limit charging current so the alternator does not run to long at full amps...which is what I did on my RV
I love the vee belt comment as it was also known as a wedge belt, noisy friction stuff.
I worry that the thermal switch solution may not be so good due to the inductive reactance of the field causing back emf high volts causing the thermal switch a problems..
Good point on the magnetic collapse and the switch. Could add a flyback diode to the switch to give a path. I should have thought of that.
This is exactly my idea. Glad I read all the responses before I typed. Isolator failure would be my only thought!
@Dean-i4d Hi, thank you for your reply....I use a rather cheap 100Amp isolator at the front end near the driver, going down the back to a proper battery isolator down the back. It gives me the ability to starter assist from the house batteries, solar can charge both house and or starter, or if need be run house loads from starter and engine alternator if the house batteries ever failed me.
The most charge I have ever seen going to the house batteries from the engine alternator was about 55 amps... which soon raised house battery volts a little and caused the amps to fall away. Lithium batteries do not mind 14.5 volts for their in built battery management to even cell charge... so there is just no need for DC to DC expensive kit if your willing to operate the battery inter connect manually.
Gotcha, makes sense and I agree with you. Keep it simple thanks for the response.
Greetings from Portugal, Europe. Not sure why your video appeared in my YT feed but nevertheless, information greatly appreciated. Thank you.
I hope you like our other offerings
so glad I heard about you from another cruiser. this is HQ content! Thanks clarke!
I just found your channel. I assume your device will apply to an RV system? I have a dual alternator system as this vehicle was originally an ambulance. I have removed the rear batteries and now have the original dual battery system for the diesel under the hood. I have upgraded one of the alternators and plan on using the other alternator exclusively for my "House" batteries which are lithium. As I understand from your video, If I install a lead acid battery as an intermediate to the lithium batteries and install the Bank Manager to regulate the alternator it should help my second alternator live to charge the lithium battery bank along with 1200 watts of solar. Thank you for this video which has come up on my youTube home page!
Yes it will work fine in an RV. In fact we just did a 3 month RV trip through the rocky mountains.
th-cam.com/video/_M0OiAi5rEM/w-d-xo.html
Referring to diode failures, back years ago, I was having issues with cheap reman. alts. I found the issue was cheap diode bridges installed in the reman's. I found a source for plasma bonded diode bridges which fully eliminated the future failure issues. The cheap bridges were soldered diodes which we all know has a low melting point. The diodes were simply falling out of the alt on the road as I drove along. Now not all alts are constructed so the diodes can simply fall out of the cases, such as late model Fords or many others. Not that long ago, I was working on restoring a Ford 7.3L powered PU which I had installed a reman alt. One day I was working on something else and sparks just lit up the inside of that reman alt. It was on account of a diode bouncing around inside the case which in the end pretty much destroyed that unit. This is the second vid I've watched today from Clark and they were both educational. I've been working on engines in boats and autos most of my life and have learned something even today after over 40 years of mechanic work. Of course very little experience with LiFePo4 batteries in cars has been the case. I'm really liking the hybrid battery concept now.
Thanks Brett.
Hope you choose to subscribe and continue to enjoy our stuff
Great video as always Clark, now that I know the bbms will protect my alternator from my lithium I can stop worrying about it.
Thanks Ian
Great Video ! The condition of the battery "spiking" is , I believe is known in engineering terms as "load dump " . I am amazed by how many people work in electrics or electronics, are unfamiliar\
with load dump , & its ability to destroy components. My first introduction to load dump was an automobile I had & the negative cable fell off the battery post (don't ask !) & every damned light that was "on" at the time instantly vaporized its filament.
Just found your channel. Love the videos and you are very knowledgeable. I learned a lot from this video. Thank you
Such an excellent video. I'm convinced you can confirm if my expensive way of keeping my alternator in check will work for my upcoming project. Mind you I'm installing these on a yamaha jetboat (because I have a very demanding audio system)
So I bought an Epoch lithium battery 12v460Ah claims the following statement on the website:
" CANBUS Communication allows BMS to communicate directly with Victron OS"
I also bought a Balmar XT 250 alternator.
I will be buying the all new Arco Zeus external regulator (it is a canbus enabled regulator similar to the wakespeed WS500)
I will also buy a victron cerbo GX. I'm hoping the Epoch batteries internal BMS will connect to the Cerbo GX to be able to enable DVCC and then from the Cerbo GX to the Zeus regulator which then will control the Balmar alternator to shut off when my lithium gets full and stops accepting charge or out of balance etc any time it shuts downs.
All concept and I already bought most of the expensive parts but really would appreciate if you would look into these specific products. I have a good feeling you will be familiar with the individual items I have listed and will have a stronger opinion on if they will be able to communicate in the way I'm hoping. Looking forward to your reply and thanks for the videos, cheers!
No I haven't put that exact system together as I solve this a different (better) way with my BankManager. It can't fail and actually charges your Li correctly unlike these devices. It's also much cheaper.
I suggest you ask this question to the guys buying from.
I see so what happens if the Lithium BMS shuts down unexpectedly, does the starter Lead Acid Battery or AGM battery absorb the extra current so it doesn't damage the alternator plus all the other electronics?@@Clarks-Adventure
Yes exactly. And since my hybrid battery manager always keeps the lead on line, it's always there to absorb the energy. Nothing can fail.
@@Clarks-Adventure amazing I’ll watch your bank manger video first chance I get to learn more
This might also prove helpful.
www.emilyandclarksadventure.com/bbms
I'm usually not commenting on you tube clips, but i think i can add some useful info.
For those who have newer boats with 2014+ Yanmar YM.. engines, they are all equipped with 125A 12V Valeo alternators, which have internal regulators - simple (dumb) voltage regulators.
The video suggests to add thermal switch in the field current path to prevent overheating the alternator when LiFePO4 is used.
Indeed, there is a Yanmar Tech bulletin out (YMTQTB17-007), which recommends to limit the charging current to 100A. This will limit the alt temp to 200 deg C, which seems high, but apparently is OK for Yanmar.
Now, a thermal switch can accomplish this, but it does not address the voltage spike problem. Here is why. I'm assuming a typical scenario with lead acid starter and LiFePO4 house battery bank, both separated by a battery isolator. The LiFePO4 batteries typically use a battery monitoring circuit (BMC), which will shut off when a single cell (there are 4) reaches its max voltage. This shutoff happens instantly with severely unbalanced cells. The lead acid battery starter battery is normally fully recharged after a few minutes and therefore won't act much as a buffer raising the charge voltage above the 14.4V limit.
The only way to remedy this is a controlled ramp down of the charging current so that the regulator can follow. So far i haven't found any specs for ramp down of BMCs, maybe someone can enlighten me.
Another down to earth and informative description...Question : related to the Lithium potential to destroy alternator diodes when a BMS suddenly cuts off the battery. If I make up 3 x groups of 3.2 v cells in paralllel (its for my 12v sailboat to replace the AGMs) If each of the 3 groups of 4 cells has its own BMS and 1 of the BMS shuts down a group of cells will the alternator diodes be affected? Is this an effective way to safeguard the alternator diodes.
Nope one BMS shutting down won't hurt the alternator.
Nope it's not an effective solution
Once the first BMS shuts down the other two suddenly get 33 percent more power are are likely to shut down ... Cascade thing
Why not just do what I suggest? You are going to have a lead battery around to start that diesel.
And there are now over 700binstalled BankManager systems that will keep your new li from being destroyed by being charged wrong.
very good insights for people, thank you Clark. 👍 Personally my next boatbis likely to need refurbishing and upgrades, along with replacements, Full wiring design check, Network Wiring, Lightning protection isolation and Bonding, New instruments (replacement originals that work, kept as spares for other boaters, and expensive but worth it Alternator, serpentine belts, external Regulator, standing rigging, running rigging, New Sails, and existing checked, valeted, and kept as a backup suit of Sails if good enough. That kind of thing. I'm still a bit wary of Lithium, after communicating with a Chinese Manufacturer. Like Lead, Lithium Hates being discharged below 50% Capacity, and you lose recharge cycles each time if you do it for longer life, they don't appear to like being charged over 85% apparently, so useful non damaging capacity appears to be between 85% and 50% , so a tual useable capacity would be 35% .? Now Lead Loves being charged to 100% right? So bon damaging capacity therefore looks to actually be 50% right, plus Lead batteries are easily and fully recyclable? Plus the extra weight, can help put displacement down low where it is useful. A badly treated AGM Battery can last as little as 18 months, but we'll looked after, 10 years. How long do badly treated Lifepo4 Batteries last ? What is their Maximum Life ? Information on those factors, are highly noticeable by their absence aren't they ? So I may go with deep Discharge Dual Purpose AGM, and Never Deep Discharge them (even with Lithium, deep Discharging Damages them. Any experience with Carbon Lead Clark ? They look interesting. As an aside, Offgrid on my Smallholding, I got 15 years outbof a bank of heavy Duty Cheap Agricultural Tractor Batteries, and only lost them thanks to Not forecasted extreme cold down to minus 45 degrees C cracking their cases. Never discharged below 50% and usually a couple of volts higher than that. I won't have "Normal" Lead acid Batteries on a boat though, must be sealed. Best Wishes. . Bob 👍
Hi Bob,
Carbon lead is very interesting and people I respect are having good luck with them. I haven't owned a set myself.
I think you might want to broaden your research into LiFePO4. I think you will find evidence that a lot of your ideas about life and discharge are not exactly right.
It's still early days for this technology but it seems to me that Lifepo4 can be fully charged as long as your charger can accurately know where 100% is. That can't be done with voltage alone so basically only my BankManager can do this safely. They seem OK with more than 50% discharge. In fact they should be stored for the long term at 50% charge. I set my lower limit to 20% so I get a working spread of 80% of rated.
@@Clarks-Adventure Good points Clark, Lifepo4 is indeed a Bit different, to Lithium, but that 85% charge maximises the service life of mobile phone batteries and Tablet batteries may point to it pointing that way for Lifepo4 as well. It was a pretty good Chinese Lifepo4 Batteries Manufacturer (pretty sure looking to sponsor me with a Housebank Set, to help them determine what the maximum useful service life could be if properly treated ) who was quite firm about the number of Recharge Cycles being harmed badly, if discharged below 50% Capacity, if done often. I suspect there could well be a way of treating Lifepo4 batteries, to get a useful service life of 20 plus years tbh. Though Tester Will Prose has said that, or at least strongly hinted, that Lifepo4 batteries will self destruct internally, a long before Cycle life can be reached. Now That I find worrying worrying enough, to seriously consider whether even a free Housebank set is really worth the bother of testing, and is certainly serious food for thought. Thanks for the thoughtful response Clark, Best Wishes. Bob (who does love testing stuff ) 👍⛵️✨️✨️✨️✨️✨️
@@Clarks-Adventure PS Me again Clark. I think I'm going to let others find out about Lifepo4 possible service Life, and as 10 years for AGM properly treated is now solidly established, I think a Carbon Lead Housebank with AGM e gine, bowthruster, and Windlass batteries as a setup for long term testing, will probably be the route I go , thinking about it. Thanks again. Bob. 👍 the edit was because the message decided to post itself before completion, so added the change of direction for me as well . 🤣
Carbon lead Firefly make lithium look cheap.
@@braithmiller eta dropped letters from words. Luckily they aren't the only manufacturers, and Carbon Lead can be cheaper by a fair bit than Lifepo4 when on offer. AGM too, for a solid 10 year service life if treated properly, such as Never Deep Discharging any Deep Discharge Battery for starters, no matter the chemistry of its construction. You just need to develop an appropriate Battery Bank size, with a good routine for managing it. One Boat Owner, no names, no pack drill, an engineer ffs, absolutely Trashed his new AGM Batteries inside 18 months, and replaced them with very expensive Lifepo4 batteries. Did he change his management regime ? Nope, so bets may be taken on how long efore he trashes those Lifepo4 batteries. I would put money on them not lasting very long at all, and likely less than 5 years. Expensive lessons should be the best Education, Right ? Should have learned from his AGM bank that he wasn't doing things right imho, a nice guy, and he will probably figure it out in the end. 🤔
(00:00) - Introduction
Clark introduces the topic: Lithium-Ion phosphate batteries vs. alternators.
Common question from viewers: How to deal with alternators when using lithium-ion phosphate batteries.
(00:43) - Lithium vs. Lead Batteries
Lithium-ion phosphate has a Battery Management System (BMS) that protects the cells by shutting off the battery when it goes outside the safe zone.
Lithium batteries can absorb power faster compared to lead batteries, which need slower charging above 80%.
(01:56) - Alternator Function
Alternators produce power (voltage × amps).
If the battery disconnects, the alternator's voltage spikes, potentially damaging the diodes.
(03:13) - Problem Explanation
Sudden loss of power when lithium battery shuts off, causing alternator damage.
Voltage spikes can affect other electrical components on the boat.
(04:21) - Example of a Real-Life Issue
A boat with lithium batteries loses power after the BMS shuts down the battery, and the alternator's diodes are burned out.
The owner didn't realize the issue until months later.
(05:29) - Solutions
Classic solution: Keep the battery connected to the alternator at all times, but not ideal with lithium as the BMS needs to disconnect for protection.
DC to DC charger: Possible but inefficient due to power loss.
Hybrid system: Combine lead and lithium batteries with a "bank manager" to prevent damage.
ABYC solution: Expensive modification with a special BMS that sends a signal to shut down the alternator before the battery disconnects.
(08:15) - Power Absorption Differences
Lithium batteries can absorb power without tapering off, unlike lead batteries.
This creates more strain on alternators, especially high-output ones.
(09:18) - Heat and Alternators
Alternators generate heat when producing power.
Fans help cool the alternator, but more powerful alternators create more heat.
(11:03) - Upgrading Alternators
Upgrading to a higher-amp alternator can cause more heat.
High-output alternators may overheat if not used properly.
(12:28) - Proper Alternator Use
Start engine, raise anchor, and avoid letting the engine idle too long.
Alternators work best at higher RPMs with good airflow.
Avoid revving the engine while in neutral as this generates heat without cooling.
(13:32) - Overheating Alternator Risks
Operating alternators at maximum output without proper airflow can damage them.
High-temperature alternators may require thermal management systems.
(15:54) - Solutions for Heat Management
Use an external regulated alternator with thermal protection to avoid overheating.
Install a thermometer on the alternator for monitoring.
(17:08) - Thermal Switch Option
Use a thermal switch to cut power when the alternator reaches a set temperature (e.g., 110°C).
This switch can protect alternators from overheating.
(18:20) - Modifying Alternators
Internal regulator alternators may need to be modified to include thermal switches.
Modification allows for better heat management and protection.
(19:28) - Upcoming Video and Closing
Clark will explain how alternators work internally and how to modify them for better heat management.
Final thoughts on protecting alternators when using lithium-ion phosphate batteries.
(20:02) - Conclusion
Clark hopes this video answers common questions about alternators and lithium batteries.
Viewers can ask more questions on Patreon for further videos.
@chazgeisler6213
Thank you so much for this. I hope you planned on me incorporating your work into the description. If you like doing this feel free to do this for any of my videos and If you would like to help on new videos send me an Email to SailingTemptress@gmail.com and we can talk about sending you links to my videos way before I publish.
Clark, loved the video. I have a very challenging problem though. My boat has 2 engines and 2 separate banks. Both banks can be charged by either alternator through a 2 alternator, 2 battery isolator. This is great when smaller similar batteries are used. My case involves a house battery bank (starboard) of lithium rated at 700 amp hours with 6 batteries in parallel. It is very unlikely that all 6 batteries would shut off, especially since the alternator really only wants to stop charging at about 14.2 volts. Since it goes through the isolator, a voltage sense wire is needed to the alternator due to about a 0.7 volt drop through the diodes in the isolator. This is one of my problems as the non house side with lead gets fully charged rather quickly essentially shutting down that alternator and now it contributes nothing through the isolator. This leaves the other house alternator doing the work to charge a 700 amp lithium battery. As you noted about alternator speed, I ussualy run 900-1100 rpm and air flow is probably not sufficient to cool this alternator resulting in a melted brush cage in my last alternator. My thought was to use a dc-dc charger from the Port Engine battery charging the Starboard engine that has the house batteries. The charger failed within about 10 hours running though. This also puts a constant 75 amp load on the port alternator at this low rpm. I am at a loss on how to get these 2 alternators to combine their strength to charge the lithium bank and have some sort of heat regulation without the 2 battery banks connected. This system was done for safety so if the house battery is depleted to a point that it cannot start the Starboard engine, then the port engine and generator battery are isolated and still full to get the generator with charger running as well as the port engine. This would charge the Starboard engine battery in short order to facilitate a start. There must be way to accomplish this without spending thousands of dollars on larger externally regulated alternators along with who knows how many other components. The temp switch may be a partial solution as I think if the voltage sense wire is disconnected, this would shut down the output and at least protect that one alternator from frying again. Getting the other alternator involved would be a bonus. Any thought by you or anyone else out there?
Wow there is a lot going on here.
I'm afraid your question deserves more time and analysis than I can give here. If you would like to drill into this design I'm confident we can come up with an inexpensive system to do what you want but it will take back and forth to really drill down to the requirements.
Take a look at our Patreon "Dream Believers" tier. If that looks good to you, its the right place for this level of question.
For short advice. I'd start by considering loosing the isolators and using a pair of these in stead
th-cam.com/video/qckmr6MgQCs/w-d-xo.html
They are cheap, and cause no voltage drop. Diodes were a great solution to this issue in the 70s but time has marched on.
U need to change your alt(or engine/or both) pulley so your low rpm spins the alternator enough not to overheat
Excellent words I now won't have to type either. Thanks.
Some have played with varistors temperature compensated. A few sailors tired of the cost of the potted voodoo regulator went hardware simple despite being programers.
I have a VSR daisy chain working well till more money. No heat at all.
Your BMS in on my wishlist.
You made this more complicated. I have a lead battery as my starter battery and is using a dc-dc charger for my agm battery. I use this in a car setup. Please note i can use a lithium battery but too expensive for my needs. My agm is only used to power my fridge during a road trip and camping. I created a video on my channel about it and works like a charm.
Your needs are simple
Others need different levels of performance.
I, and many other commenters, believe this was just as complex as it needed to be.
Not really.
Ask yourself this. What voltage do you set your dc-dc charger to? The more research you do the more you will realize there is no correct answer. You can't safely charge li to a voltage.
Lithium requires a specific charging method that simply can't be met by those devices.
Yes I'm talking about lithium specific chargers of all types.
They all charge to a voltage. What voltage?? It's different for every current being delivered to the li cells.
@Emily & Clark's Adventure
The Renogy DC to DC charger can be set to 4 different voltages by setting the 5 "dip switches" to a predetermined configuration. 14V, 14.2V, 14.4V and/or 14.6V for Lifepo4.
It also can be set to charge LA. 12.6V, 12.8V and/or 13.0V.
I'm using the 14.4V (lifepo4) setting, which is widely recommended by many manufacturers of lithium batteries, including mine.
I know. I own one. I'm saying there is no right answer for every charging rate.
If you charge at 20 amps one day there is a setting that's right. Then the next day you charge while there is a load, say your refrigerator is running at 7 amps. Now you are charging at 13 amps and you need to stop the charge cycle at a lower voltage.
There is no one voltage that doesn't cause low current overcharge. This causes irreparable damage to the cells.
Also repeatedly not charging to full causes memory.
I just picked up 2 100A Eco worthy lithium batts and likely won't be long before wanting a BM regulator from you Clark! In the meantime I might do a little DC to DC charging experimentation.
Careful with overcharging if you charge slowly
I'd set the charge limit to something like 13.8v and have it float to 13.3 right away after it hits 13.8v
A decent alternator's regulator will catch the disconnect before the spike and disconnect the winding in the alternator.
I've jumped cars with no battery in them MANY times wity a jumper pack, and then pulled the jumper pack off once it was running, and I've never blown alternator diodes.
I have seen a slight spike in the brightening of the under hood light, but that was it.
I'm guessing the load that a car draws is larger than a boat possibly, and doesn't cause a huge spike.
Exactly. Modern cars have a high base power draw. Boats have virtually 0.
Hello my name is James Mason and I live full-time in my 1967 GM TDH-4519 new look city transit bus, it has a Detroit Diesel 6v71n with the Delco Remy Dn-50 gear driven oil cooled brushless 12 volt 225 amp generator but I plan on replacing it with a 450 amp version, i would like to get a Wakespeed ws500 controller but i don't know if it will work with a dc generator. I plan on having one 1000 ah lithium iron fosphate battery bank using 520 Headway 38120 hp 8ah cells for both house loads and starting the engine. What would you recommend?
I don't know much about modern generators. The last car I had with one was a 1955. I'm really surprised you aren't using an alternator. Maybe it's a bus thing.
That's a lot of headway cells. Like 500. Those things aren't cheap. Why not go with big prismatic cells?
And a BankManager of course.
@@Clarks-Adventure the reason I am going with the headway 38120 HP cells is because they put out enough current to start my bus and they are cheap, about 200 USD for 48 cells. I forgot to mention that I will be using a Rec 500 amp bms that also controls contactors for input and output and that both the Wakespeed ws500 and the Rec bms will be connected and controlled by a Victron cerbo GX
How much for the 12v rec?
@@Clarks-Adventure about 500 usd
Great info, thank you. I have a Hi-bred Bp Chassis + LiFeP04 House. Morning is the high load 35A if the load goes over 35A the current to the LiFeP04 is chopped (not by the BMS). I don't know what is cutting the power. Any suggestion? 1993 Commons Diesel powered Motor-home.
Have you looked into Starlink "Flat Mount"? I have, Looks Great. If you buy a Land Based, it can be Up and Down graded for Marine Service.
Thank you Clark for this excellent episode. I have one question though. What if I have starting battery Lithium as well. Please let me know..
I don't recommend that.
The major reason I developed the BankManager approach to a hybrid battery system was to use each battery chemistry to its strongest advantages. With all lithium you loose the passive alternator protection and honestly the cheap easily replaceable starter battery (I bet that li starter cost a mint!) As well as a reliable battery system to fall back on.
We went into all that pretty deeply in the document the ISO asked us to write docs.google.com/document/d/1a5M0V9JjaMezCZjJwrGv0IhCekAy-r_X6PPKs1YG8dY/edit?usp=sharing
If I were you I'd use a lead starter battery.
Something like this.
th-cam.com/video/Xp6ssk4Guuc/w-d-xo.html
4:29 would the voltage spike happen in an automobile with a lead acid battery if you disconnect the battery while the car is running? I’ve seen people do this to check to see if the alternator and after learning about lithium I’m wondering if that has been a problem over all these years?
It really could but seldom does in cars because of all the many electrical loads a modern car has. These loads provide a path for the power being produced to flow through.
Boats operate most of the time without an engine running so they have few constant loads.
Good point about loss of battery load killing alternator, especially on diesel with no engine electical load. How about simply keeping the alternator / regulator always lightly loaded with a couple of engine comparment light bulbs?
Our RV (Pleasure-Way) uses the factory Mercedes Sprinter 200 amp alternator connected directly to 2 100AH Lithium batteries via a timed switched solenoid. The amps range between 90 and 130. It seems to function well.
Glad for you.
Have you ever had the BMS disconnect?
I’ve always asked myself if a blackout was possible when BMS disconnects.. wasn’t sure if it only disconnected from incoming power or disconnected the whole thing.. now is clear.. doesn’t sound good to electronics and a little annoying..
Thanks for discussing this! But why so hard on DC-DC Converters? Yes it's another green or blue box but I installed one it works flawlesly and doesn't need a lot of attention, you can easily adjust on charging profile, set voltage, amps, duration so it can nicely work together with what you already have. No need to fiddle with alternators, easy install and not more expensive than alternator and regulator upgrades. Very easy to live with last 2 seasons, and solves both issues you rightly brought up here! While Lithium takes a charge so easy you hardly have to max out on alternator power, In parctice I rarely draw more amps than 1/4 of the rated alternator output (115A), most of the times its set to 25A.
I have used dc-dc chargers. Sometimes they are a good solution but usually they aren't. My issues:
They are mono-directional. Can't move solar power to the start battery.
They waste power (minor issue with power to heat but major issue since they can't pass much power. As you said seldom 1/4 of the power available.
They don't charge li correctly. They charge to voltage not to full. See my recent video on the BankManager for a definition of low current overcharge.
They are basically unnecessary. Hybrid batteries are better if managed property.
But we are all captains of our own ships and should do as we wish.
@@Clarks-Adventure true, all choices are personal, only wanted to add my positive experience here.. to react to your points:
I connected the solar power to a Blue Sea 1-2switch (after the solar charger) to choose banks manually. When not aboard it is switched to the lead acid starterbattery. The DC-DC Charger can be set to stop charging the Lithiumbattery ones Tail-current thresholds are reached, in combination with the apllied voltage (eg 14,0 Volt at the Li-battery), just like the solar charger or the shorepower charger (all monofunctional on purpose). I am least worried sofar on the efficiency of the setup, more to (losing) simplicity and how to save or enhance some sort of redundancy. I am very interested in your creative solutions and will sure look into the benefits. Many thanks for your time and efforts!
Which dc-dc are you using? I've only tried the renergy.
Be careful with the battery combiner switch. If your lead is quite discharged li can try to send LOTS of current into it. We have seen some smoking wires during tests.
@@Clarks-Adventure I installed the Mastervolt MacPlus 12/12-50 2 years ago, as part of a total overhaul of the electrical system. Can also act as a stabilized (max 50A) DC-source, so if Lithium is down engine can be used as generator (for basics: nav, autopilot, lights etc, not microwave). This Blue Sea switch has deliberately no combiner function, it is in to be able to maintain control over the solar charging.
Thanks
I should do that thermal switch idea for my driveworks alternator in my 98 Ford van
First, you never never tie an alternator to a lithium battery. A LiPo will draw as much current the alternator can supply. A DC-DC converter is needed which has current limit capabilities. This setup has been in my Van for about 2yrs. 3-100@hr batt's. Works great!
Did you actually watch this video???
@@Clarks-Adventure I did, I must have missed why this is wrong. My setup can never draw more than 40 of 160, and the alternator is never hot. The cells balance evenly. What did I miss?
Seems like your alternator doesn't have overheating issues. Many don't. I'm not sure why you are only getting 40 amps out, you might want to look into this.
The bigger problem is what happens to your alternator diodes when your Li BMS shuts down during charging. That's where the lead protects your alternator diodes.
@@Clarks-Adventure Its a 50 amp DC charger, but I've never seen it charge at more than 40 to 45. And that's with it hooked up on the solar side as well, but the switch off. So it lets the alternator charge at more than 25. Power going through it is supposed to be a one way thing with how it's set up but I'm gonna look into this more, thanks.
I'm personally not a big fan of dc-dc chargers. They do current control but there are cheaper, more reliable, ways to derate your alternator and of course they don't know how to properly charge lithium even if they have a Li setting.
I know you are talking about a boat system what about 12v lithium car battery I've seen these as drop in replacement for car batteries and they come with built in car jumper feature in case the end user accidently drained the battery by leaving on some kind of accessory; headlights for an example, it could jump it's self. I know it's not a boat set up but how much different could a marketed car battery and alternator be from what's used in a boat other than voltage and amps ?
I'm just asking because I thinking about getting one
There are exceptions but generally "drop in replacements" aren't really.
Most aren't up to starting a car engine.
@clark what you described with the blackout and then restart sure sounds like what happened to the Dalle container ship. Any chance there is a connection ?
Nope. That was bad fuel filters I think
Excellent video Clark. Really informative. Thanks
Nice of you to say Larry
THANKS for putting this video together.
You're very welcome
Hope you enjoy our other videos as well
@@Clarks-Adventure been thru them numerous time and purchased (but not installed yet) a BBM+
Pleasant surprise hearing big sciota!
Great video! I am new to lithium batteries. I had an AGM battery in my cargo trailer hooked up to the alternator from my tow vehicle so it would charge along with the tow vehicle's battery while driving. I recently bought a LiFePO4 100 AH battery for the cargo trailer because I want to put a solar charger on it, and it has a 100 amp BMS rating. Basically I had the cargo trailer AGM battery in parallel with the tow vehicle's lead acid battery for charging off the tow vehicle's alternator when driving. I have a couple of questions. #1 - Can I even put a LiFePO4 battery in parallel with a lead acid battery and charge off an alternator? #2 - If I can put the two batteries in parallel will the tow vehicle battery act as a shunt to prevent the voltage spike when the LiFePo4 BMS shuts off?
I have several videos on this topic . You can do it manually but it's best to use my BankManager if you want the best life from your batteries.
I suggest you watch through my videos on the topic. Check out playlists.
Good stuff….I want to switch to a LIon battery on my Corvette. The car has a Holley EFI system with a Mechman hi amp alternator. The alternator is triggered via a programmable output from the EFI system. At this point I’m using an engine rpm setting to control output but if I set/configure voltage and temp limits (I have a temp sensor in the engine compartment next to the alternator) I should be able to “protect” it from these issues you touched on …correct? Again good stuff 👍
I wouldn't count on that setup being fast enough to react to the BMS going off. The voltage from the alternator goes up really fast. Digital software controlled systems have quite a lag.
Are you trying to save weight?
Maybe run without a BMS and balance the cells with an active cell balancer as described in another of my videos.
Or maybe super capacitors?
@@Clarks-Adventure I just realized the battery Im considering is a Lithium Iron Full Spectrum unit with no BMS …..May be a different scenario than what you are referring to in the video ….Thanks for the reply 👍
@jsanch1892 no BMS means no premature shut down.
But also means no protection
Question: if you are running Lithium for the house and Lead for the engine that are connected to a magneto (modern outboard engine) do the overheating concerns still apply? Given the continuous running nature of a Magneto do we just let the BMS do it’s job to regulate amp charging of the Lithium batteries ? Or do we still need a bank manager or dc-to-dc charger?
You still want the BankManager as the voltage regulator in the outboard wouldn't treat the li kindly.
I just don't have any experience with what happens when you remove a battery from a modern outboard so the diode protection may be unnecessary but the li charge controlled is very important.
Well, I picked up some thermal switches. Looking forward to the next video so I can learn what to do with it.
Someone suggested a potential problem with this. He might be right. Adding a flyback diode might help protect the switch for longer life.
I'll talk about it in the description of the next video. Too late to film anything.
@@Clarks-Adventure I'm looking forward to it. I recently upgraded to 200Ah of Lithium (27' sailboat) and I've been a little worried about how the rest of the system.
I just updated the description of this video to talk about it. I basically said check wikki.
What I really should have talked about in the video was venting the engine room. I think I'll add that to the description now.
I enjoyed this video. The idea I had when you were talking about using the lead battery to protect the alternator when the lithium battery opens it’s circuit and stops charging was, would one of those super sized capacitors used in audio amp installation work in place of the lead battery? The capacitors I’m talking about are over 1 farad and some even have digital voltage displays built in. Capacitors life generally lasts longer than lead batteries. Just a thought. Thanks for the interesting video. This is the first time I’ve seen your channel.
Technically it would solve the problem nicely.
But,, it creates so many problems of its own. It's hard to control current with one of these. Its charge acceptance ability is scary.
Electrician here: The voltage spike from open circuiting a large 12 volt alternator under max load can exceed 1k volts. This is why a TVSP device will help protect the alternator and all of the electronics in such events if you have a battery disconnect switch of any sort, including the BMS. If not using a lead acid battery in parallel, I would go with an adjustable external regulator that will connect to the BMS of the battery to regulate both current and voltage to provide optimal charging within the required range of the lithium battery. One can even set the output voltage of the alternator regulator slightly below that of the PV array charge controller settings so that the array will be prioritized over the alternator, plus the output of the alternator can be controlled to allow for de-rating if overheating is occurring. I believe that there are now can-bus controlled alternator regulators that will integrate with the entire system.
Those lithium iron batteries are a big investment, and one will want to get the longest life out of them.
The heat created by the alternator is a function of the winding resistance, the power output/field strength, the alternators cooling fan, and the temperature and volume of airflow in the engine compartment. The reason we use alternators over generators is that they have the ability to provide a fairly large output even at low RPMs by increasing the strength of the field windings, creating more current flow in the windings, thus more heat while the alternator fan and the engine fan are operating at low levels, thus causing more heat buildup under slow RPMs.
Normally this is not an issue in running basic electronics and keeping the starter battery topped off, as the alternator will just be idling well under its rated maximum output. But add a load like a lithium battery capable of keeping the alternator at max output continuously, and that can really stress the alternator. One can help overcome this by using the above mentioned regulator, and by also using electrically operated and thermostatically controlled fans to cool the engine compartment, along with de-rating a larger alternator. A 100Amp alternator will have 1/2 the winding resistance of a 50Amp alternator, and will run much cooler when outputting 50Amps than the 50Amp alternator running at its maximum output.
Would a further option be to add an invertor as the load on the alternator and to feed that into the existing smart charger? Kinda like a DC to DC convertor but employing the existing smart charger. (Note: i charge my batteries from a stand alone gen set, by feeding the smart charger).
That seems really unnecessary and a huge waste of energy.
The hybrid battery approach with a BankManager gives many many advantages including proper charging of your Li bank for much longer life.
@EmilyAndClark Can you explain why you consider it a waste of energy? Inverters have an efficiency of 85% plus and so do smart chargers. Moreover, if I am only charging this way when the engine is running, the increase in diesel fuel consumption is marginal. Isn't the issue more a question of whether the smart charger will accept an imperfect sine wave (although mine accepts the output of a Gen set), cost and space (would need a 40 to 50 A Inverter). Not keen on the alternator being dedicated to a (lead acid) start battery as would have to reconfigure or remove the combiner arrangement.
You can do it anyway you like. I suggest this approach.
www.emilyandclarksadventure.com/bbms
Sure it's like 20 percent heat waste TWICE. If that doesn't bother you go for it. I'm not going to engineer your system in a direction I don't believe in.
My approach has a lot of advantages but if you only concentrate that it's the only way to charge li correctly for a long life that should be enough. It's just extra points that it is a simpler more robust approach.
I run a dual alternator set up and have my battery bank on a 375 amp alternator with a external adjustable voltage regulator. Works great.
I don't understand.
Alternator hooked to battery works. Of course it does.
@@Clarks-Adventure Clark, I think he is just saying that he has a system setup as he notes and it is working out really well - thats all. I dont think he was posing any sort of question at you.
Thanks, after reading and answering hundreds of questions I guess everything starts looking like a question.
Your termol switch if u can't find can u use a small 12v hot water thermostat for your on and off just says?
Most BMS only disconnect charge. So if the BMS disconnects and destroys the alternator the power doesn’t go out as the the battery discharge mosfet is still turned on. A big alternator will produce less heat for a given amount of power owing to its lower internal resistance. Another method that works is to find the continuous happy current of the alternator and you then extend the charging cable to add enough resistance to reduce the current. F have a 14.2v Alternator then you subtract the lithium voltage it spends most of its time charging at which is around 13.6v so you just need to drop 0.6v at your chosen amps. Many systems already drop this anyway but it generally doesn’t need much extra cable. An advantage to this method is that it also produces a short current taper towards the end of charge which is what the cells like. This is one place where resistance in the charge circuit works to your advantage using the very flat charge curve of lithium in order to work. I can now say from my own feedback that dozens have used this method in hybrid systems to good effect. So long as the correct cable is used that can safely carry the max output of the alternator then no rules are broken. I too believe that DC-DC chargers in this situation are the spawn of Satan. I’ve just scribbled the software and built the hardware for a regulator that can measure voltage, current and temperature and regulate based on all 3, I only did it as I got a 180A smart alternator for £20 where the internal regulator is useless as it’s controlled by the car management system and so had to be bypassed anyway. It’s really stupidly easy and cheap and has wifi monitoring and setup.
any plans to do 48V. i have a NiFe battery comprised of 36 600ah cells i had to put this in a shed do to hydrogen off gassing. i interested in expanding with Lithium LiFePo4 but have been looking for a way to get them to play nice. this looks promising but i could only find 36V version
The BankManager does 12, 24, 36, and 48v
All hail the alterntor god 🙂 Thanks for the tips. Useful.
This content is great! Thanks!
What is the minimum size Watt hour lead acid “shunt” battery required when using lithium batteries?
Just installed a Mechman 400 amp alternator that can handle 250F+. This will feed a 4000watt inverter installed in F250 truck crew cab to charge my electric motorcycle. Ordered a 16 Amp NC. Temperature switch. Will also use a fly back diode. Might get another one to monitor the starter batteries for the inverter temp sense input. Exciting stuff 😅
Lead size with a BankManager is all about what's required to keep your charging system "sane" when the li is disconnected.
Some systems require more than others
Starter type batteries work best but they should seldom be power cycles of course
@@Clarks-Adventurejust looking for the formula to calculate the lead acid battery size needed to shunt the back EMF generated by alternator when the BMS disconnects the 140 amp hour Lithium battery. For example . Will a 1 amp hour lead acid battery work?
If you let the BMS shut down your Li damage is happening to that li. Use a BankManager. BMSs aren't battery charging devices. They are for emergency situations
Usually a car starter battery works
What's wrong with getting around the BMS cut off problem by just connect a lead acid (or AGM) battery in parallel with the lithium?
That's what I'm saying.
But without a bankManager one of the batteries won't charge right
Personally I like the idea of regulating my power input from alternator to LiPO, even if it cost me a little power. It will extend the life of your alternator and battery if you have a well matched system. No need for lead batteries, could even use capacitors to start your engine.
You can't use capacitors, they can deliver an insane amount of amps for only a very short time, and then they present a total dead short to the charging system...
As far as "regulating" the power input from alternator to the LiPO, all you need is a battery that has an actual 'intelligent' BMS system, or just get a battery from a good brand like Victron energy. You get what you pay for.
@@brnmcc01 done this 10 years ago on my beater car, no issues just looses charge after a few weeks but if you can recharge at will not an issue. What do you think solid state batteries are?? Victron is expensive and you can do the same circuits yourself at least that way you will have knowledge and recourse when it brakes down ! If you gonna try this today just be careful with your circuit protection, new stuff is uber sensitive to intermittent voltages, like you can fry some components especially memory.
@brnmcc01 Bombardier uses a capacitor to start small 2 stroke engines currently in production. I don't know enough to know how that scales, but it does exist.
I have a small outboard and want to charge my new LIPO4 battery from the outboard. The 5 amp alternator is built in to the outboard. Do I have the same risk of blowing Diodes if the BMS turns off the LIPO4 battery? I don't have a starting battery since the outboard is pull start. Do I still need to add an AGM to protect the LIPO4? Can the AGM be a motorcycle battery, (~20 AH)?
You won't hurt the outboard alternator because it's designed to operate safely with no battery attached at all.
But your alternator will charge your Li like lead. If you never charge the li fully no problem but if it fully charged the outboard will be the absolute poster child for "low current overcharge" which kills LiFePO4
What about this scenario: In a vehicle, using a LiFePo battery as an aux battery, installed with a battery isolator? The alternator would charge the lithium aux batt, and the lead acid starting battery, and would always have "something to do" w/ regard to charging and operating the vehicles systems as it did prior to putting in the auxiliary lithium batt. Am I missing something? I'd like to add an aux batt to my truck, and lithium sure is appealing! Thank you!
(edit: for context, the aux batt is only for running a portable refrigerator that runs at 60 or 45 watts, depending on Eco mode selection ... so I'm not trying to power heavy equipment)
From the alternators point of view no big issues assuming it's continuous duty.
From the li batteries view. Yuck. It's going to be cooked being charged like a starter battery in a car. 1 to two years life, tops.
You should use this instead of the isolator.
www.emilyandclarksadventure.com/bbms
It will control the charge to the li
Does a Ballard external regulator protect the batter from BMS shutdown or you would still want a hybrid or secondary battery? Thanks great video
You would need the second battery.
Very informative. I bought a NOCO lithium battery for my motorcycle. Is this scenario possible? What remedies can I use if that's the case? BZY91C18 diode?
I dropped a little Li into my bike years ago. My bike has a 1.7 liter engine and the lead batteries just didn't last long or reliably crank it over.
I've had no problems but I certainly wouldn't need 15 years out of it to feel I got my money's worth.
Honestly I'm not even sure it's a LiFePO4.
So what I'm saying is those are different little beasts. They live hard and I bet they will die young but in the scheme of things don't cost much. The banks of li I'm referring to in my videos cost a lot more and, in the boat case, are taken to places where replacement is nearly impossible. They have to be reliable.
How about the Epoch Dual purpose 12v 120Ah cranking, deep cycle battery?
Would they work ok with a Boat alternator?
How about swapping a 12v RV battery with the dual purpose Epoch battery? Would I need to change my inverter?
No regular engine alternator should ever be connected to any BMS enabled Li battery.
Outboard alternators trade efficiency for protection from battery removal.
The best way by far is the BankManager hybrid system. Besides its ability to protect components connected to the batteries it is the only charge algorithm out there that doesn't damage Li by low current overcharging.
marinedcac.com/pages/bankmanager
How about Lithium replacement in lights duty diesel truck? Replace the main battery with Lithium and keep the second as Lead to keep the alternator happy? Still need the Bank Manager?
Yes or your alternator will kill the li. Li needs to be charged properly or it will give you a short life.
If I have my lead acid starter battery connected to the alternator and completely separate from the lithium house bank and solar panels, is there any disadvantage to this other than being unable to charge the house bank with the alternator or use the starter battery as a backup house battery? If I go with this setup, what typebof syarter battery would you recommend? I understand that your videos and other resources should make this all clear on their own, but it's a lot to take in. Thanks!
Not anyway near as much work as making them was for me
Put the effort in. If not on my channel elsewhere.
And once you understand the situation you will find you want a BankManager. It's the only way to do it all right.
But you have to learn for yourself or just buy my product out of blind trust.
Hi Clark I’m just watching one of your videos and you mentioned fitting a Lithium battery into a standard AGM battery Box , I have a Projecta power hub Battery box which has a 300 W inverter built in , and built in BMS , ot says a lithium battery can not be installed, is there a way round this as I like the Box , Thanks Clark Keep the great Videos coming 👍
It boils down to how the li is charged. And I assume your current device doesn't have a BMS but a charge controller. BMS is a li thing.
I'll likely do that video eventually. If you are good at reading between the lines take a look at this. th-cam.com/video/odhuEauAvLU/w-d-xo.html
You will see me charging that Redodo with my BankManager as a charge controller.
I assume you either charge this "box" or use it. This can be done. But it would be DIY
I have a lead starter and 2 AGM house batteries commected by Yandina battery combiner. My alternator is connected to my lead starter and the Yandinas feed the AGMs. I wonder if the Yandina would save ny alternator when I switch my house batteries to Lithiums...
Well yes but your alternator and other charge sources will kill your Li.
Hi Clark, Rick Moore from Sophisticated Lady Explained the installation of a second 48V 5kW Balmar alternator, with individual Balmar regulators per alternator and a centre fielder to sync the alternators. The output of the alternators connect to a common buss with a feed to the 48V LiFePO4 battery system. So I don't know what happens to the alternators when the batteries get fully charged? His YT video SSL667
My toyota hybrid does not have an alternator, Will a lithium battery instead of the 12V lead acid battery hirt the 12V charging system in the phase converter?
Your charger circuit is going to treat the LiFePO4 like lead.
It will work but won't last a long time.
Does the size of the lead acid battery matter in a hybrid setup? Can I use a small lawnmower battery?
I'm assuming you mean one controlled by a BankManager.
The BankManager doesn't cart but you need enough lead so things stay sane with your charge controllers after the BankManager disconnects the li.
Generally as long as you aren't using a cheap Chinese inverter/solar controllers with many kw of panels most anything works for lead
Thanks for the video. What about CAN-aware alternators that are designed for charging lithium batteries?
I have seen a lot of gear that says it is for charging li. But I've found flaws in all of it except for constant current chargers that plug into the wall and only charge li that is not in service.
Well except for the BankManager.
I of course haven't seen every offering, no one has. But one gets tired of looking.
But I just realized you are likely talking about alternator regulators that shut down on a signal from the li BMS. Sure that works. I mention it in the video. Works but expensive.
@@Clarks-Adventure Thanks for your reply! Here is a video by The Fit RV that goes over many details about the CAN alternators - th-cam.com/video/sSYoi7_t640/w-d-xo.html
I watched the video. Thanks.
I can't tell what logic the BMS is using to request a charge but if it's correct (that's not a given) this should work fine.
My issue with this approach is you need to use batteries with a special BMS (read extra expensive) and change all your charge controllers to canbus units (also extra expensive). That's all of them. Solar, alternator, mains chargers, wind...
I designed my system to work with any regulators that work for lead. And you can spend your money on more Lifepo4 cells.
and of course I trust my devices ability to know when the li under its control is exactly fully charged. The BMS might be doing that well but let's just say it was a difficult problem to solve.
@@Clarks-Adventure Excellent. Right it's a matter of cost difference and also being a different implementation. Thanks for watching that and giving your insights and comparing it to your solution presented here! I see you do have a truck camper as well and I watched that tour video by Emily a few weeks ago not knowing this is the same channel. Keep the spirit!!
I'll be doing some testing with that truck once we get back to the US next week.
A overland RV company is having trouble getting modern trucks to charge external batteries. I happen to have one of these modern trucks so I'm going to hack the charging system.
You wouldn't have any insights into it would you?
This may explain a similar problem I'm having. I recently replaced both batteries in my wife's BMW. One was toast, the other, 5 years old, but still working fine. It's worth noting that these two batteries look and feel like a regular car battery, except they are $350 each. Something about the battery having a BMS made them so pricey. About the same time, I bought an old boat and needed a battery for it, so I just used the BMW battery. After a few months, the alternator on the boat started putting out 18-20V. It was the original alternator from 1995, so I replaced it without much thought. A couple months later, now my new alternator is also outputting a 17-19v. I'm starting to think the BMW battery is killing the alternator voltage controller.
Batteries with a BMS can just turn off. Alternators hate when you remove their battery. All your other electronics hate when alternators have a bad day.
So I want to deck out my electric system in my Catalina 22. The goal is to do the Texas 200 comfortably. But is ac, inverter and lithium to much for such a small boat such as mine?
Sailing is a hobby. Do what makes you happy!
What about using that temperature switch to disconnect the LFP bank from the LEAD starter battery? Just a solenoid or relay. Those bimetallic temp switches are cheap - just glue 2-3 100C in series around the alternator housing - if any of them trips - the alternator has only to supply the regular operations.
If the li is hungry and you disconnect it but charge up the lead reconnecting can be dangerous due to the low internal resistance of the li. There can be quite a current surge.
In real practice with a good well protected installation I'm sure it would work.
I like how you are thinking.
@@Clarks-Adventure I can see that case happening. True.
How do we reduce that inrush current? Adding some variable resistance?
What about adding a longer wire? The voltage drop is proportional to amps flowing when I remember correctly.
Used to study electrical engineering, but went into a different field after a while 😉 I like those kind of puzzles.
@sebastiant5695 current control is difficult
Best done with transistors.
Just keep it connected to the lead and use the BankManager to manage the li like I say in the video. It's really the best and safest way.
I have a Yanmar 56hp diesel which I think has an 80amp alternator. My starter battery is two 6V deep cycles in series for 12V. I have a victron 18amp DC/DC converter fed from alternator to two 12V 206ahr SOK LiFePO4 batteries.
I like the idea of the thermal switch and having spare diodes on board.
Any advice or critique here?
BTW, really love the way you explain things. I am a retired chemist and typically chemists and engineers don't see eye to eye. My eyes , and ears, are wide open. Thanks
Captain Qwiksword
SV Gratitude
Cocoa Fl.
Thanks.
I'll assume your request for discussion is for others as I'm on record.
Also glad you read about the flyback diode.
I love the fiddelplay 😊
thinking of parallel connection (pbo2 & lifepo4), alternator connected only to pbo2, hopefully balance-charging changes the lifepo4 battery too :).
thanks for bringing this to our attention :).
You should consider the BankManager for that.
www.emilyandclarksadventure.com/bbms