Out of all the you tube channels that I've watched on upgrading to lithium batteries you are the first person to address the problem of compatibility between coach and motor batteries. This was a real concern of mine. Thank you for sharing your solutions to this problem.
@@AZExpert I have a question (hand raised) I contacted the battery designer and i asked them can you set the charge to be lower so that you can use a alternator too charge they said in the app you can set the charge to the same as non-lithium batteries from the factory and run them at 78 percent and they said this configuration will allow the alternator to rest and the b Batteries will turn off the charge early allowing the alternator less stress and it wont overheat.
@@AZExpertI have 1200 watts on my roof and 600ah for AGM battery now. I'm going to lithium, my charge controller is already capable of lithium so I think solar will give me that extra 10% to top off the lithium over the the standard charger. What do you think?
Thank you for this - People tend to really overthink the switch to Lithium and sooooo many folks think they're a safety issue when they absolutely are not. I've worked in the UPS industry for over 22 years now. 19 of those years were spent handling escalated customer issues at APC/Schneider Electric (who are the biggest manufacturer in that industry). I have dealt with hundreds (if not thousands) of potential safety issues with lead acid batteries. Explosions, fire, leaks, venting/swelling, you name it. With LiFePO4 I have dealt with exactly zero. Not one, not ever. They are fantastic. From a vendor perspective I have seen the failure rates and they are pretty much zero. When they do fail, it's typically more common to see a BMS failing, or maybe a physical connection like a bad screw terminal or something to that effect. The actual batteries are insanely good and rarely fail. Its great great stuff.
James, congrats! You covered the main points perfectly. I live in southern Az and have a trailer. I installed a lithium in my trailer and it works and charges perfectly. The only suggestion is I did change over the main board of my WFCO converter/charger. Cost under $150 and was a 5 wire install! Took 10 minutes. Again, thanks for the clarification. Lithium is an easy install for trailers. Motor homes and vans do have the alternator issue that must be addressed. Lastly, When my truck battery died on the road, I sat for an hour allowing my trailer lithium to charge my truck battery through the 7pin connection. It worked. High voltage always flows to low voltage. I was able to start the truck and get to the dealer for a new truck battery! Thanks again. David
Even at 80-90% charge on the lithium, you still get more than twice the ah usage as a comparable lead acid battery. I have had many clients who finally upgraded after I told them this and they are all extatic with the results. Fore those that have 120v fridges I installed two LiFePo4 batteries. For any of them with solar installed, they never run out of juice. The isolator, I did not know about. I will be installing these from now on. Also, installing larger current alternators is usually easy. Thanks for making this more public! Good for business. Ryan at Glenwood RV Repair in Colorado. Ps. Love your videos! They have made me a better rv tech.
Another way - since many 'RV size' engines commonly have mounts available for a second alternator (as many also are used in ambulances, etc. that require two alternators), is to install a second 'constant duty' alternator (not a second OEM alternator that is still NOT constant duty.) Those alternators are built to stand constant output and have a thermistor built-in as a safeguard.
James - I have the same Magnum Energy MS2812 as you have in your motorhome. They absolutely do work on lithium batteries as I did this conversion about 5 months ago (4x230Ah). I changed out the board and the remote (less than 30 min job) on the MS2812 and it now has the Li battery profile. I did not need to do this as the original board and remote would allow me to customize the charge - as you showed - to CC/CV (constant current/constant voltage). I did not have to really change anything on my 2014 Dutch Star to handle Li batteries. However, I did elect NOT to charge my Li batteries using the 250 amp alternator from the engine. If I want to juice the batteries, I simply start my 10kw generator and within an hour, the batteries are topped off. The chassis batteries are still being charged by the alternator. With a 10kw generator, there is no need for expensive solar stuff. With our setup, we can be off grid for about 5 days (920 Ah) and with a genset, we are only limited by the black/grey tank capacity. Great videos.
Very good points. I think i'll do likewise and isolate the the alternator to charge only the chassis battery- gas engine, and let the combination of solar and genny take care of the house lithium.
Thank you for creating such a clear and practical guide on lithium battery upgrades. You've outdone others who've tackled this subject and provided all the necessary information without trying to sell anything. Bravo!
Yes you helped someone. I need to replace my coach batteries anyway so moving to LiFEPO4 is making a lot of sense. My coach is a 2001 Monaco Dynasty and the expense and effort to replace all the inverters, charge controllers, etc. was keeping me from jumping to the new batteries. Finally someone explained how to do this and removed my fear. Thank you. Now to buy the right equipment!
I used the Li-BIM without trouble for 3 years, but switched to a Renogy DC-DC+MPPT this year. When the LiFePO4 batteries got almost completely discharged, they pulled >100A from the alternator/chassis battery. This tripped the 100A breaker I put between the Li-BIM and the chassis battery, so I could only charge from the AC-DC converter. The Renogy DC - DC converter does 50A Max, and can be adjusted downward in 10A increments. It still charges the coach batteries faster than the Li-BIM, because of the on-off duty cycle of the Li-BIM. The DC-DC charger products have improved a lot in the last 3 years. I don't regret buying the Li-BIM, but better options exist now.
You confirmed my hunch about using PV to top off the batteries as a more cost effect way on an older rig than changing out the perfectly good inverter/charger. I like the solution for the charging off the alternator. I might jump in now.
I have a 24 year old Georgie Boy 26 ft class A motorhome. I have been doing a major renovation and used AZ Expert's videos extensively when I completely replaced the roof two years ago. For the past few months I've been working on the electrical system. I kept the original house battery and engine battery but disconnected the house battery from the 12 volt house circuits and removed the original charger/inverter. This original house battery now serves only as a backup to the engine battery. Both of these are charged by the engine's alternator. To manage house power needs, I installed an independent 48v EG4 LiFE house battery that is charged via a Growatt 3 kw charger/inverter. Through the Growatt, the EG4 battery can be charged by shore power, by the generator, or with 800 watts of solar panels on the roof but not by the engine alternator. So when I am hooked up to shore power or running the generator, the 120v feeds through the automatic transfer switch to the Growatt charger/inverter. The Growatt unit normally routes the 120v directly to my 120v AC breaker panel. The Growatt also charges the 48v battery. If there is no incoming 120v, the Growatt automatically inverts 48v DC from the battery to 120v AC and feeds it to the 120v AC breaker panel. The 48v DC runs through a 48 to 12 volt DC converter, and is distributed to the eight 12 volt DC circuits in my motorhome. When I started the project, I expected it to be very complicated but was amazed at all the things the Growatt can do, and how much simpler it was than I expected. I'm not pushing Growatt over other manufacturers, it just happens to be the one I got, after seeing it on the Will Prowse channel and I'm sure others operate similarly. As AZ Expert mentioned, the electrical equipment available for RVs are getting smarter and thus easier to use. Jim
You can re purpose your battery isolator to charge your chassis battery with the solar and never need to lock down the boost switch again I know you took out the jumper relay its just in case your new relay leaves the chat your solar will charge the chassis batterys. Just put the wire from the house batteries to the alt side of the isolator and number one to the chassis battery, it works great on my Monico. Keep it going. We all Love your work.
You are absolute right that LiFeP04 batteries are safe. But poor installation of LiFeP04 can. And many RV do have poor electrical systems that do not present a big problem with LeadAcid batteries. But install LiFeP04 and it can get dangerous. In my RV the cable from the converter to the batteries was not able to transfer the 60A to the battery. With lead acid not a problem as lead/acid do not accept higher amps for a long time. With LiFeP04 this cable got very hot. Always install a T-fuse directly after the lithium battery. T-fuses have an interrupt current of 20000A. “Normal” fuses can weld shut. The BMS is just an on/off switch for protecting against under/over voltage and temp. It does not replace proper charging equipment.
You have answered many of my questions concerning the lipo4 batteries. I have opted to keep them on a Seperate Circuit. I can top them out with an eu2200i and ac-dc charger or solar power. The Lithium circuit charges the Chassis battery via a trickle charger/maintainer. This keeps them isolated from one another. Also have a 700w inverter on Chassis side for power on the Move which can also run the Ac/Dc charger for the Lithium bank so on arrival the Lithium is topped off with little to no strain on the Alternator.
Great video! A few points I think is good to make. If you buy a quality battery for the most part you don't have to worry about longevity of the battery. Most quality lifepo4 batteries will have charge cycles exceeding 3500. That means you can charge/discharge down to a reasonable percent (20% is usually the absolute lowest you should go) that many times and still see 80% of original capacity. Not charging to 100% will only make this number better. That means in 10 years your lifepo4 battery will still be 80% of what you purchased! Also when selecting a battery make sure it has a hot AND cold cutoff sensors especially if you're in those climates. Lifepo4 doesn't like being too cold or too hot and will damage the battery, this cutoff sensor will prevent damage. Some batteries come with built in heaters that'll keep the battery above a damage voltage. Either way, great install!
Excellent video. I think you have discussed all the important points. I have a 2022 class A on the F53 chassis. When I upgraded to lithium I spoke to Lion Energy and Battle Born techs and well as Victron. I changed out the converter, added a Victron DC-DC charger and changed my ZAMP solar controller setting to lithium. Because I’m always concerned with electrical connections and shorts I paid a local repair shop here to check and confirm everything was good. 16 months later and everything still working great. I truly appreciate your videos. Thank you
I installed the Renogy 50 Amp DCDC converter rather than that smart relay you used. The Renogy included a 25 Amp MPPT solar charger as well. If solar is installed, the Renogy unit will charge the starting battery from the solar panel after the coach battery is fully charged. It was very easy to install and configure. It doesn't required a start or run wire from the vehicle. It works great and absolutely limits the load on the alternator to 50 amps as opposed to the relay that AZ Expert used that has some voltage thresholds and time intervals. I just didn't want to load the alternator at 100 Amps.
That's my plan as well. I already have the a 40A DC-DC charger. 100A into a the right set of lithiums is probably low actually. The fact that these things do that for several minutes and then switch off.... I don't want that much stress on the alternator for 15 seconds, let alone 15 minutes. I'm an electronic technician. This is not something I would design for intermittent service. If you have to shut it off periodically because it's too much current, don't feed it so much current in the first place.
@@EliTuber Today I have a single 170 Watt panel that gives me about 7 Amps in full sun. So I can add two more of those before I max out the 25 Amp charger capability. I' used wire I had bought for another project. It looks to be 10 gauge? It's wire rated for outdoor solar panel use.
@@EliTuber Sorry, I didn't see this earlier. I had a single cheap 170W panel from Amazon. I could run for a few days before needing the generator. I recently installed a second 170W panel and that is awesome. The single panel would charge at 7 to 10 amps. I went with 10 gauge wire. Probably overkill.
You did a great job explaining. I would also remove the alternator charging rectifier and replace it with a smart one but install it away from the alternator and engine. Then when it gets hot or the amp draw decreases then it lowers the output or shuts down. if you cant afford a smart rectifier than moving it and adding a big heatsink will help keep it cooler. Heat as always is the enemy of electronics.
Excellent! This is the information I've been waiting for. Thought I would have to change / upgrade the alternator in my 2000 Beaver. Thanks James! You rock, buddy!
Thanks so much, James! My factory installed equipment was similar to yours on my 1997 Safari. I called Battle Born after purchasing my equipment from them.. I ended up setting up the equipment improperly and until I saw your video I did not realize it was not correct.😮 I won’t bore you with the details, but I just wanted to let you know you helped me get my system installed properly. I had previously installed a 240 amp alternator so I do not know if my original installation would have damaged my alternator over time, but I am thankful to have the equipment hooked up properly now.
Glad I gave a listen, my Foretravel MH has a switch to tie all batteries together for starting, not just a momentary Emergency start switch. I'm putting 2 of those liop4 batteries to replace the 3 8d gels. Never considered the Alternator limitations or the Em start solonoid issue you've brought to my attention. I have a portable 3-30-200 amp charger that I could rig to boost 200 amp for emergency start with the EM start switch instead ( generator running, shore power or inverter powering the portable charge/ boost) . Almost like a snake eating it's tail in the later mode. 😂 I didn't even think of the Isolator issue and the stress on the engine alternator. Guess that funny looking Isolator Amazon was offering me, without explanation, had some merit. Thanks for the video.
I used to have the same battery isolator in my 2000 Monaco dynasty. I went the DC to DC charger route on my coach with a 40 amp Renogy Unit and I’m happy with it.
James, great video on this much debated subject. Very clearly outlined as usual and simple enough for me to understand the steps and reasons for the choices. Thanks, PZ
Just wanted to let you know, that I absolutely loved your video. I thought I had researched lithium batteries fairly thoroughly, but I did not realize the charging issue. My system currently has 1800 amps of charging from the roof solar. And I'm charging 4-6 volt AGM batteries wired in series and parallel. These batteries are about 3 years old and I will be changing them to lithium at some point in the future. Thanks again for your thorough advice.
great timing, I was doing this build over the past 2 months. I just pulled 2 strands of 2awg through my van from the front to rear and through the rear floor. Next is to build some battery packs.
Great job. I appreciate your taking the time to do this. I was going to upgrade to Lithium when my supplied RV house batteries were 3 years old in my 2020 class A gas puller, but my WAFCO unit was not Lithium compatible. I considered buying an inexpensive standalone lithium battery charger and plugging it into the 120-vac outlet in the compartment where my inverter is installed and direct wiring to the house battery terminals at the input of the inverter to charge the batteries when plugged into shore power or when the generator was running, but it would not have solved the alternator issue. I was hesitant to do a DC-to-DC charger since it was something new to me (I am a retired electrical engineer but that doesn't make me an expert in these systems). Instead, I invested in two good 6 v Golf Cart Batteries which should last me about 5 to 7 years. Buying then from my Golf Cart center, I was able to get good quality batteries very reasonable. The two batteries were about $330. They will soon celebrate their second birthday and still aren't fully broken in. I have installed a small solar system (200 W) on the roof with an MPPT controller and I carry 200 watts of portable solar panels in the belly of my unit with their own solar controllers to set up when I'm stationary for a while. Since we have a residential refrigerator and only 2 house batteries, we need to run the generator 12 hours a day to keep the batteries charged. With my solar, I can reduce it to about 2 to 4 hours depending on the sunlight. If I converted to LFP batteries, the solar would probably keep them fully charged so I wouldn't need to run the generator. With the continued reduction in the price of the LFP batteries, I might be able to cost justify the conversion next time. That Precision Lithium Battery Isolation Manager is affordable so the entire conversion will probably be possible for about twice the cost of staying with Lead Acid Golf Cart Batteries. We only boondock a week or two a year, so it is difficult to cost justify the conversion cost. With my current solar system, if I were to save 4 hours of gen time each day we boondock and we boondocked 14 days (we've never done that many), I'd save about 2 gallons of gas a day (we have a 5500-watt Onan gas unit) for about 28 gallons of gas a year which is about $100 a year based on today's gas prices. Of course, $100 per year over 7 years (battery life) does pay for it, but we have to run the generator 45 minutes a month anyway. We're not sure how many years we will continue traveling in the motorhome, so it's hard to cost justify much in upgrades if we won't benefit from them. If I do decide to convert, thanks to your video, I now have a path to do so.
Good video. I probably would have switch that signal battery momentary rocker switch to a off/on rocker switch and add a relay to ignition so ignition is disabled when switch is in on position while charging the chassis batteries. This way you don’t need pry something in the momentary rocker switch to charge it and RV can’t be started while the switch is in on position charging the chassis batteries.
AWWW, this is an excellent vid. I now know I can buy and realize an roi by replacing my lead acid with a lipo4 battery☺ using existing charge controller and inverter in my towable! I also, have learned I can reach a 100% by using a lithium charger connected to battery and/or using solar with lithium charge controller. Again, thank you.
I bought an EarthX LiFePo4 battery intended for experimental aircraft, it weighs next to nothing and seems to be able to crank over anything normal, so not a huge diesel, but, it’s limited to 80 amps for charging. I put SB connectors on it and on all my vintage Volkswagens, mowers, skid loader, and one on the end of half a pair of jumper cables. It works so good, no more having 15 batteries and 15 battery tenders and all these have small generators or alternators that are less than 80 amps, so working great for me. But it is a $450 little battery. Really appreciate this video, just about to start the upgrade on my Damon Tuscany for lithium and solar and really needing information so I can hopefully do it once, correctly.
Thanks for the information. I upgraded my class C coach battery to lithium a couple years ago. Tons of information online telling me I had to buy more stuff to make it work. I kept all the same stuff, only thing I did is change the monetary emergency start switch with a non-monetary one so I could charge the coach battery while driving. It rarely gets above 40amps. The lithium coach battery would not charge unless the switch was pressed. This video gave me some peace of mind. It good to know. what I’m doing isn’t too bad.
All good points you make. I went through this with my 5th wheel when adding lithium bats. Kept the stock charger knowing it can’t fully charge. Once I add solar I’d use the mppt w/ correct profile to charge or if I decide to add Victron multi plus 2.. my truck to trailer I don’t worry about it on the dodge as the small wiring limits the draw on the alt. Your video is well done and thought out. Your common sense is refreshing.
My LFP house battery install on my Triple-e Commander Diesel, I installed a time delay relay on the sense switch terminal on my DC to DC converter, and for my chassis battery maintenance I install a small 10Amp 12volt Trickle charger to keep the chassis battery topped up, I have a a Magnum MSH3012M Hybrid inverter charger (hybrid in you can supplement your shore or generator power with house battery inverter power, so say you have 115VAC 15amp plugin, and you turn on the Convection oven, it will draw the 15 amps from your shore / generator and the balance from the house battery / Magnum Hybrid inverter, truly awesome upgrade. My custom profile for my battery setting on my Magnum for Lithium is I use 14.6 on absorb, also set the inverter cutout to 11.8volts even though they can go down to 10VDC but that will initiate the Lithium BMS shutdown. I still have a Reliance configurable low voltage relay to prevent the house battery getting to below the BMS cut out but I have not installed that yet but might when I sell my coach. I normally ab bit anal when it comes to watching my power situation when dry camping, I have fun doing that! I am a retired electronics Technician and love the tech!
Wow! As an old Rver, this is interesting, I don't even still own an RV. But, I am interested in lithium for home us. I just came across Ur channel, very intertaning,
Great information ! I used the Renogy 50a Dc-Dc mppt charge controller, it uses solar first and then bucks up the alternator as needed. It can also be tuned back as needed. Your videos are top notch !
Keep an eye on that Precision Circuits LiBim relay. I had one in my system, thought I could just run my house batteries down to nothing since they were Battleborn, what happened was the LiBim somehow got confused and in a closed state, meaning it wiped out my coach batteries also overnight. The problem I see with that LiBim is it tries to do too much with only a rotary contact inside. It can become confused, it clicks all the time and you really have no idea why. Finally I went with a DC to DC converter. I just didn't want my coach batteries and house batteries to ever be completely connected together again. Luckily I had enough solar to wait a few hours in the morning to start the coach by using the signal terminal to provide enough start voltage.
I also found an issue with this LiBIM. The name implies it will act as a battery isolation module and allow you to connect both batteries using a momentary switch. When the momentary switch is not on, the batteries are supposed to be separated, but I found this not the case. I found that my chassis battery was back feeding through this LiBIM after I shut off my house battery disconnect and solar disconnect. I found my victron Cerbo GX still had power getting to it from the LiBIM from the chassis battery. I plan to add a second battery disconnect next to the LiBIM to isolate the chassis battery from Victron components. This back flow only happens when the LiBIM timing circuit is battery connect position for active alternator charging. When timing advances to its rest state, the back feeding issue stops.
This is great information, I hadn't heard about this. I removed all other chassis charging setup to prevent them causing issues like this. I didn't like the idea of a dc to dc charger in this battery bay either as it is not weather proof and still has acid batteries too.
Now I’m having that same problem with mine. I thought there was something wrong with my battery bank. My LiBIM isn’t clicking anymore. It used to click about 10 seconds after cranking the engine now only when I pushed the momentary switch. For some reason my battery bank isn’t charging while driving any more. I have to spend some time troubleshooting.
Some DC to DC chargers like from Victron and Renogy are compatible with lead acid on one side and LiFePO4 on the other. Also some are isolated or shared ground. We have the victron on a circuit with a breaker for 3 years now on our Tiffin zephyr with lead acid chassis batteries and lithium house batteries and it works well, no issues and its customizeable and can be monitored through bluetooth on the app, and you can set a lot of parameters when to start charging, such as only on when the engine/alternator is running, and how your charging output would look too
One day when I break down I hope your around. You know your shit! I installed my system on my travel trailer and love Lithium batteries. I replaced my charger on my trailer that gave I think 30 amps with an inverter/charger from Renorgy. 3000 watts with a 6500 watts boost for 2 seconds and 65 amps charging for my 200 amps of Lithium batteries (small system but capable) Runs my tv and Starlink for 36 hrs none stop. Love my system and it gives me coffee and toasts anytime, without the dimming of lights as before with lead acid sometimes had to run the truck engine for a Keurig coffee before. I can start the air conditioner no problem and run it for 2 hours (current draw of 1200watts or about 100 amps). However I only run it for 30 minutes when stopping for lunch and it damn hot outside. Thank for the video, cheers from Canada!
My LiTime Lithium Batteries are fully charged @13.5 volts. They will absorb and eventually float to 13.8v daily. I use Victron Shunt and Network to monitor it and Victron MPPT to keep topped off everyday. Really enjoy the graphs provided by Victron in the App.
James, thank you for this video. We presently own a 2022 Winnebago class A gasser. Two years ago replaced the two lead acid coach batteries with BattleBorn. Installed a DC-DC charger, a new Progressive Dynamics converter-charger and reset the charger controller. The system works great but I always wondered with 200 watts of solar on the roof, did I really need to replace the converter-charger. After seeing how well the solar charges the batteries, and after seeing your video, maybe I didn’t need the new charger. Thank you for the videos. Very easy for the me to understand.
You did a great job !! I have pretty much the same setup. I removed my Big Boy and installed the Li-Bim.. I left the Signal Lead off. However, I did have to run a separate wire with 12v and fuse for the power of the Li-Bim. Going on 2.5 years and no issues.
Thank you for your very simple explanation about charging the Lithium batteries. I currently have a Xanterx Freedom 458 Inverter/Charger in my 2006 motorhome, I am hoping that installing the Lithium Battery Isolation Manager will allow me to charge while driving down the road along with the solar that I will be installing.
Thanks James. I'm on the finals step of doing the same upgrade on my 2003 Dynasty. In 30 minutes, you compressed months of research and in some cases misinformation. Just for a basepoint for others to design around I went for 2 batteries with a total of 600 Amp Hours powered by 4 panels totaling `1,600 Watts wired 2P/2S fed into a Victron MPPT 150V /100A solar charge controller. I removed the same 3 components (The battery booster, the isolator and the "maintainer"). I am in the process or adding the Progressive Circuits Li-BIM 225 Lithium Battery Isolation Manager even though I have a 200 Amp alternator. Total cost including tools, wiring connectors and Dicor was around $3,500 and can go 5 days off grid on sunny days without conserving energy. As a note' Magnum Energy sells remote control panels with Lithium profiles.
Three years ago I upgraded our '05 Four Winds class C Ford E450 RV house battery from a single SLA to dual 100ah AGMs. Not an easy job either as I had to build a second platform. I had considered Lithium at the time but cost then was more than our budget allowed and charging profile of our 45amp Parallax converter/charger seemed unable to correctly satisfy the requirements. Prices today for LiFePO4 types have come down to the point of the AGMs of 3 years ago so when the current ones are done I might just upgrade. The alternator issues concern me the most I suppose. Thanks for sharing as always.
Just upgraded to a LiFePO on out travel trailer after the deep cycle it came with died, I did use a LiFePO charger to charge to 100% before installing it, but the current WFCO doesn't have any LiFe settings. I'm also adding a 3000W inverter charger and 460AH LiFePO battery, 400W solar this month for an upcoming boondocking trip. Your videos on the LiFePO was very informative, dig the other videos across the other platforms too, keep up the good work & "Hi" from the west valley!
I have the same Magnum that you have, and it is fully programmable. I can even select a custom profile to meet my needs. The programing is done at the ME-RC50 remote. You use the custom profile in the Setup page. The problem with not getting to a "full state of charge" is that most of the sealed drop-in batteries do their balancing by having the BMS charging FET's turn off at 14.0v and then use the voltage above that to do passive balancing while the cells are really not being charged other than by the balancers at 70-100 mA. I checked the specs on your battery and that is exactly how it works. If you do not charge to more than 14.0v, you will get no cell balancing and that will cause the cells to drift out of balance over time.
This is the first I've ever heard mention of fear of fire. I made the switch 2 years ago to lithium batteries and it was the best decision I ever made just got a new travel trailer this spring and switched it over to lithium immediately and now 100% off grid for as long as i want
James, you look to be doing well. Seems like a lifetime ago we worked at LMRV! I'm suspect of that Precision Circuits unit. Seems a few commenters are having issues with it. My first concern is the size. It may say it's rated for continuous 225 amps, but I must question that. Any solenoid with a true 225 amp rating is quite a bit larger. Thus disapates more heat. 225 amps can generate a lot of heat. That is why those diode isolators went ot of favor. They could get quite hot and the RV builders rarely had them mounted in a location to get decent airflow. Anyway, my 2 cents worth. Happy Trails!
Nice video, this subject has been coming up a lot lately on the forums. I did this conversion on my 97 Monaco Dynasty 3 years ago. Built my own LiFePO4 battery and used a bluetooth BMS with it so I could monitor and control charging, charge states, etc. from my phone. In my case I went with a Renogy 60A DC-DC charger as I wanted complete isolation and reasonable charge rate, and the cost was low (on sale). I connected the oem 80w solar charger (non MPPT) to the chassis circuit to keep my chassis batteries topped up. I just wanted to point out that if you are using an converter/charger that doesn't have a lithium charge profile, and thus you may be using less than full cutoff voltage for the batteries, it is a good idea to occasionally charge using a charger that DOES have a lithium profile, either a solar charger (as in your rig), or a DC-DC charger (as in mine). The reason for this is that the BMS will do cell balancing during the charging, and the most beneficial period of time for this is in the upper "elbow" of cell voltage, which you may not achieve without the lithium profile. Over a large number of discharge/charge cycle the capacity of the battery could be lessened if the BMS isn't able to keep the cells in balance. Keep up the good work and ignore the naysayers, LiFePO4 house batteries are a game changer.
Thank you for the very helpful information about using the older converter/charger on my travel trailer with a LiFePO4 battery. I had deduced, based on vague comments on other sites, that it would work but not give a full charge. Thanks for confirming that. I will stick with the onboard unit for now and use solar as described to "top off" the charge as I hit the road for the '24 RVing season.
Magnum inverter/charger can fully charge lifepo4 batteries. Capability may depend on model etc. On my magnum I use the constant current constant voltage profile.
There are some magnum inverters that support lithium charge profiles, you just need to make sure you have the right display unit. I swapped out the existing ME-MR25 for a ME-MR25-L for a 150 bucks. You need to make sure the ME-MR25-L has version 1.3 on it to get the Lithium charge profile. My existing unit had version 1.2 software.
Depends on your application mostly, I don't like cold camping so it's not something I worry about. Many batteries have the option, or you can re-locate inside a more heated bay which I would recommend to minimize battery complexity and wasted current draw for the heaters.
😅 On cranking amps to start 25:59 the engine! Thank you for your alternator protection tips as independent of the BMS. Question about the temperature you are running through your upgrades. I am concerned about running solar in colder temperatures where the volts from the solar panels are higher than at 77 degrees.
I have solar and a new converter. I found with 500w of solar and 400ah of lithium battery I would still run low after 3-4 days in glamis. Particularly if it’s cold and I need to run the heat a lot. Or it’s cloudy. I installed an 80a lithium compatible converter and now I can just run the genny for an hour or two and juice them up pretty good if needed. New converter sends 30+ amps to each battery, whereas the factory one would only push 5-8A each.
Thank you for addressing my question about the Li-BIM. I've been contemplating whether it truly protects the alternator. I'm preparing to upgrade my Class C motorhome.
Very nice video thank you...now I have a question: according to the wiring diagram for my 22 Jayco Alante 27A, the generator uses the house batteries to start the generator (an Onan 5500). Will the LiPO4 battery be able to get that done? Or will the generator require more than the 200A my LiPO4 battery will put out?
Thanks for the video James I have a 1998 Patriot that is set up like yours with the echo charger and the boost solenoid. When Vatrer put their 460 ah battery on sale I decided to copy your installation. I replaced 4 6V GC batteries with the Vatrer, took out the isolator and echo charger, disconnected the boost solenoid and installed the BIM. Everything seems to work fine and the battery initially charged to 99% SOC. Now it has dropped to 75% SOC and it is not charging even though it is plugged in. I am guessing this is the BMS keeping it from charging until it gets to a low enough SOC. My problem is the chassis batteries are not charging when the house batteries are not charging so they are getting low as in 11.8 volts. They will charge if I hold down the battery boost button. My inverter is a heart freedom 15 and I set it up to charge at 13.4 volts with the dip switches. Are your chassis batteries being charged enough to avoid a low voltage situation? Do you know of any way to isolate the chassis batteries and charge them seperatley? Thanks Carl
thanks for the info on emergency start switch. I have a trailer now with Lithium batteries but in the past had an old Class C which I remember that button. I will keep it in mind when eventually move back to a Motorhome.
Thanks for the detailed info, my friend is looking at a 22ft. 200k coach but has acid starting and agm coach batteries and I was going to suggest lipo4 instead but for simplicity's sake I'll leave it alone.
With my trailer I disconnected the charging wire from the seven wire plug. My solar charges the batteries as I drive. Don't want to burn out the alternator on my truck.
This is great into. Thanks. I want to do this with my yr2000 Dutch Star. My Charger inverter are pitiful now so may upgrade that, to something like a victron 3000. My fridge is still elec/gas and works great. But if/when it goes with go to standard 110V. Again, thanks for the well laid out info. No not super detailed but much more than I know before!
I carry the largest Noco boost pack with me. It’s probably the best stand alone jump pack you can have when you are out camping and may find yourself unable to start your rig.
As you discovered the Li-BIM 225 is bidirectional which directly connects a Lead Acid battery with a LiFePO4 battery system, with charging current flowing either way (not good). A likely scenario is that a heavy load is shut off on the chassis side (starter off) while the Li battery voltage is low (isolator connected) causing the alternator to give massive charging amps to the Li battery. The isolator can't react fast enough to disconnect because the Li battery is pulling down the alternator voltage below 14.4v. The specifications on the Li-BIM 225 allows 1200 amps for up to 30 seconds. Therefore the Li battery BMS will isolate the Li cells as amps exceed the maximum for the Li battery. When that happens, it is like pulling off the battery cable from the Li batteries at maximum amps. The voltage spike will cause the alternator diodes to fry. This is called flyback voltage. SInce the Li batteries are isolated by the BMS, there is 0 volts on the coach side of the RV now. The alternator sees a load of 200-300+ amps, then 0 amps. What does the Li-BIM 225 do now? Everything is off. You now have to manually reset your Li battery and diagnose the red alternator light on the dash. As you can tell I don't like this system. What these companies don't tell you is what happens when the BMS isolates the internal cells of the LiFePO4 battery. It is not predictable - massive load to no load instantly. So what do I like? A DC to DC charger that always gives a proper voltage and amps to the LI battery so that the BMS is never going to see voltages or amps that will trigger an isolation event to the battery. It will never overload your alternator and the wiring is as simple as the Li-BIM 225. To charge the chassis battery from the Li side I just use a trickle charger powered by the inverter, but if you have solar (I don't) you don't even need that. I really love your channel and what you do, so please don't take this critically.
I appreciate the information and comments. I think there are many scenarios that could be imagined, even dc to dc could fail, I am not sure I follow your situation completely. From my prespective, damaged alternators is already a more rare possibility with LiFePO4, but adding a dc to dc and battery tender has increased complexity for most DIY and technicians. Most Frieghtliner chassis already have a ECU controlled circuit which cycles the rv charge solenoid if chassis power gets too low, and for over 20 years, these BIRD systems have cycled thousands of times connecting and disconnecting every 10 seconds to one minute as the loads cause spikes to the alternators. The Libim225 just changes the parameters slightly
LiFePO4 is also sometimes abbreviated as LFP. These cells like to be kept at 100% all the time, which is the opposite of what NMC Lithium Ion cells like, which is about 80% charge unless you need to utilize the full capacity for a short duration. This topic has even become an issue with Tesla, which recommends the 80% setting for NMC models and 100% on their LFP models. In fact, they recommend charging to 100% at least once a week to maximize cell life. Really great coverage of the topic, James, it's much appreciated. There are far too many myths and similarly few down-to-earth discussions of the topics you mentioned.
Well, yes, LiFePO4 doesn't mind being charged to 100%, but that isn't why Tesla wants people to charge LFP vehicles to 100%. The reason is simply that the charge curve is so flat for LiFePO4 that the BMS / shunts / whatever monitoring you have for battery state of charge, can't keep track of the state of charge accurately unless the battery is charged to 100% every once in a while. For Tesla this meant that the vehicle was unable to accurately calculate the remaining range when people only charged to "80%" (which itself is a guess by the vehicle because "80%" is still in the flat part of the charge curve)... and sometimes caught people out. The main issue for longevity is to avoid discharging the battery all the way to BMS disconnect very often, and in particular a lithium battery (of any type) should never be left completely discharged for weeks or months. That will destroy the battery.
Even though 100 Amps is a lot to draw from the alternator, the LiBIM225 only connects for 15 minutes, then disconnects for 20 minutes, and cycles like that when in charge mode.
@@talk2hubba yes, it has a small draw while running, but the relay I intalled is bi-directional so it does charge the chassis when gen or shore is chraging too. Otherwise, I'd likely just connect a permanent battery tender to the chassis batteries
Idle current capacity of your alternator is KEY. It will do full output at idle. If you dont rev up your motor you will typically not get you rated output current. It will overhead. You NEED the fan speed. And burn up your alternator. And like he said that truck pigtail will not carry current you will need on a depleted lithium.
I put this on my Class A. What I’ve found is the cycling of the charge causes my chassis battery to connect and disconnect the alternator output often. Mean I park, RV running, and when I open slides the chassis battery voltage goes between 12.7v and 14.4v every few seconds. Kind of surges while opening the slide.
I went with a Renogy Rego DC-DC which is bi-directional, not a fan of the Li-BIM cycling it relay at high current every 15 minutes vs DC-DC regulating with semiconductors. Plus Rego can buck/boost voltage where BIM just connects both sides at same voltage. Wired a dumb Cole-hersee in parallel connected to dash switch for emeregency boost.
I'm also not of fan of the cycling BIM. It still puts significant load on the alternator and my existing BIG BOY w/ Bird controller isolator works just fine. So I went with perhaps the cheapest solution for my coach and just connected the ignition signal to the unused GENSET input on the bird controller. This has the effect of opening the BIG BOY relay anytime the engine is running. Basically I don't want my alternator charging my big bank of Lithium's at all. I have enough lithium capacity to easily run the entire coach loads on my longest drive and if for some reason they were low I would just start the generator while on the road to charge my Lithiums. I've been running this way for several years with no issues.
Put a lithium iron batt in my motorcycle in Phoenix, AZ and was in the for 4 yr. No problem except it did not like to start the bike cold, had to leave the light on for a couple minutes to warm up the batt due to current flow. Expensive but much lighter.
Solar is indeed the way to go. I have a 2004 Tioga class C with two residential grade solar panels I installed on the roof. A 310 W panel drives an MPPT charge controller for a 100 Ah lithium battery which runs a 2000 W inverter for a two-outlet branch circuit I installed in the coach independent of the coach AC shore power system. It provides all the power we need for the coffee machine, microwave, toaster, and TV. When we're not camping (which is most of the time) I disconnect the solar and charge controller from the battery and let it sit idle for three months at a time per the manufacturer's advice for maxing out battery life. I also have a 255 W panel driving another MPPT charge controller for the two lead-acid house batteries, which I'm going to replace with a 100 Ah lithium battery. Rather than worry about converter and alternator compatibility, I'm just going to unplug them from the new battery. If the solar doesn't keep up with the DC load then I might have to rethink things, but the RV has a generator which we never use and we do a lot of dry camping and have never run low on battery power with the lead-acids, so I'm hopeful that this won't be an issue with the superior lithium battery.
I took out 8 lead battery's {all rv Battery,s }then put in 4 lpo 12oo amp hrs with 1150 watts solar also change alternator to BALMAR CONTROLLED SYSTEM .Now seven years later everything is fine.when I did it I was the only one in us to do this,no RV manufacturer did this or would do this.
Great info, just clarify the 14.4+ volts are needed to balance the cells. The BMS will not balance the cells completely without a top-off voltage. You are correct that you can use lithium on a standard system. However, this will degrade the cells faster than normal. You had some great recommendations on how to handle the top-off voltage. solar being one of them or using the alternator system in a motorhome. almost all converters that have been made in the last 15 years can output 14.4+ volts. It’s usually either some kind of jumper wire that looks like a telephone plug or some kind of smart controller that also uses an RJ-45 jack. Check with the manufacturer before you buy new equipment.
most lithium batteries don't want to be charged at 100% all the time so undercharging to 80-85% will not damage them, BMS keeps cells balanced while charging too
I would check with Magnum about that "Equalize" setting on with your Magnum Inverter/charger. The head tech guy at Magnum told me on mine that it should be set to off. But also check with your lithium battery manufacturer.
Wow, someone that knows what they are talking about, perfect information, I have see so many people on boats/yachts that think they can up the alternator to 200 amps only to find out they are lucky if they get half that... maybe some day when someone comes out with a water cooled unit and separate voltage regulator... I used to wind by hand electric motors for electric vehicles, and I would tell people the motor will be drawing 50-80 amps in cruise, meant nothing to them... A 100 amp hour battery will not supply 100amp hours, I could go on and on about this.... clicking on my name will take you to my utube on motor winding stuff...
Thank you, the first video answered a lot of questions I had, but your second one confused the crap out of me. I have been waiting to install lithium but I have been worried about the alternator issue. Your test meter showed too much voltage going to the starting batteries I think, won't the solar boil the lead acids, your meter also showed the house and starter batteries linked in the lithium was charging the lead acids, won't that cook them , Thank you once again this is a hard issue for me to wrap my head around also wasn't that one unit you removed for linking the batteries when your starter batteries were dead.
Our 2003 Newmar Dutch Star D.P. has 2 IOTA 45 amp charge controllers with a phone jack system receptical in the side that I can get a plug that plugs into it and it changes the charge profile to one for lithium batteries. l
Exactly all the details the other lifepo conversion videos are missing! Thanks, subscribed! Am I missing something or can't you just switch off the house batteries before and during engine operation to protect the alternator?
@@AZExpert Thanks for the reply. I'll have to see what outlets/appliances are on that. Might not be a big deal to lose house power when travelling. We've also got a mechanical toggle switch up front that does the same thing. I'll have to see if that also prevents alternator charging. We've got solar direct to the battery, so if I can leave the battery on with the app, but shut it off with the switch, it'll still be getting a charge at least.
Completely different scenario, but, I ran yellow tops in my boat for about 12 years. The same yellow tops the entire time. Last year I started to notice I could only get about 3/4 of a days worth of trolling from my batteries. They were finally dieing off. Slowly but surely. Those yellow tops were given to me from a guy I know who drives a KW for a living which had a climate control system installed that ran off of those batteries, 4 of them, and he switched over to an APU and GAVE me those batteries. They run about $300 a piece. So for the same money, I bought 2 LiPo4 lithium iron phosphate batteries. 100 amp hours each. The yellow tops weighed about 70lbs a piece. I was utilizing 3 of them, 2 for a 24v trolling motor and 1 for a 12v radio, then I still had the original starting battery, also a lead acid battery. The new lithium batteries weigh 35lbs each. BIG difference. But, I can go 3 full days of trolling on them without recharging and still be at about 35% on the batteries. They are amazing. That being said, I did have to buy a new onboard charger that could handle both types of batteries, a 4 bank charger which was an additional $350. But for a guy like me, who spends as much time as possible on the water that I can, I don’t think I’ll ever go back to the lead acid batteries. The up front costs will be gained back over time, they weigh at least half of lead acids, they deliver way more power for way longer, and are simple to maintain. Plus, I don’t have to keep my onboard charger plugged in 24/7. Just long enough to charge the batteries then done. Well worth the money, just have to be careful WHO you buy from.
James, excellent information! I have two questions, with my fiver, did I understand that I really wouldn't have to add anything to it switching to the LifePo4 battery just that it would only charge to %90 capacity? Also, is there an issue with going to 2 - 230 Ah vs 1 - 460 Ah as I would save $400? Thanks for all you do in helping us RV'ers.....Kindest regards, Ted
For a Class C or smaller, just get a beefy portable lithium battery jumper. Always handy to have around, as you can give other people a jump without risking your own electrical! They usually double as flashlights and USB power banks, too.
Out of all the you tube channels that I've watched on upgrading to lithium batteries you are the first person to address the problem of compatibility between coach and motor batteries. This was a real concern of mine. Thank you for sharing your solutions to this problem.
Wow, thank you!
@@AZExpert I have a question (hand raised) I contacted the battery designer and i asked them can you set the charge to be lower so that you can use a alternator too charge they said in the app you can set the charge to the same as non-lithium batteries from the factory and run them at 78 percent and they said this configuration will allow the alternator to rest and the b
Batteries will turn off the charge early allowing the alternator less stress and it wont overheat.
@@AZExpertI have 1200 watts on my roof and 600ah for AGM battery now. I'm going to lithium, my charge controller is already capable of lithium so I think solar will give me that extra 10% to top off the lithium over the the standard charger. What do you think?
Great video
Thank you for this - People tend to really overthink the switch to Lithium and sooooo many folks think they're a safety issue when they absolutely are not. I've worked in the UPS industry for over 22 years now. 19 of those years were spent handling escalated customer issues at APC/Schneider Electric (who are the biggest manufacturer in that industry). I have dealt with hundreds (if not thousands) of potential safety issues with lead acid batteries. Explosions, fire, leaks, venting/swelling, you name it. With LiFePO4 I have dealt with exactly zero. Not one, not ever. They are fantastic. From a vendor perspective I have seen the failure rates and they are pretty much zero. When they do fail, it's typically more common to see a BMS failing, or maybe a physical connection like a bad screw terminal or something to that effect. The actual batteries are insanely good and rarely fail. Its great great stuff.
Thats incredible to hear. Thanks for sharing, I'm glad we share similar pov on this
James, congrats! You covered the main points perfectly. I live in southern Az and have a trailer. I installed a lithium in my trailer and it works and charges perfectly.
The only suggestion is I did change over the main board of my WFCO converter/charger. Cost under $150 and was a 5 wire install! Took 10 minutes.
Again, thanks for the clarification. Lithium is an easy install for trailers. Motor homes and vans do have the alternator issue that must be addressed.
Lastly, When my truck battery died on the road, I sat for an hour allowing my trailer lithium to charge my truck battery through the 7pin connection. It worked. High voltage always flows to low voltage. I was able to start the truck and get to the dealer for a new truck battery!
Thanks again.
David
Even at 80-90% charge on the lithium, you still get more than twice the ah usage as a comparable lead acid battery. I have had many clients who finally upgraded after I told them this and they are all extatic with the results. Fore those that have 120v fridges I installed two LiFePo4 batteries. For any of them with solar installed, they never run out of juice. The isolator, I did not know about. I will be installing these from now on. Also, installing larger current alternators is usually easy. Thanks for making this more public! Good for business. Ryan at Glenwood RV Repair in Colorado.
Ps. Love your videos! They have made me a better rv tech.
Another way - since many 'RV size' engines commonly have mounts available for a second alternator (as many also are used in ambulances, etc. that require two alternators), is to install a second 'constant duty' alternator (not a second OEM alternator that is still NOT constant duty.) Those alternators are built to stand constant output and have a thermistor built-in as a safeguard.
James - I have the same Magnum Energy MS2812 as you have in your motorhome. They absolutely do work on lithium batteries as I did this conversion about 5 months ago (4x230Ah). I changed out the board and the remote (less than 30 min job) on the MS2812 and it now has the Li battery profile. I did not need to do this as the original board and remote would allow me to customize the charge - as you showed - to CC/CV (constant current/constant voltage). I did not have to really change anything on my 2014 Dutch Star to handle Li batteries. However, I did elect NOT to charge my Li batteries using the 250 amp alternator from the engine. If I want to juice the batteries, I simply start my 10kw generator and within an hour, the batteries are topped off. The chassis batteries are still being charged by the alternator. With a 10kw generator, there is no need for expensive solar stuff. With our setup, we can be off grid for about 5 days (920 Ah) and with a genset, we are only limited by the black/grey tank capacity. Great videos.
Very good points. I think i'll do likewise and isolate the the alternator to charge only the chassis battery- gas engine, and let the combination of solar and genny take care of the house lithium.
Thank you for creating such a clear and practical guide on lithium battery upgrades. You've outdone others who've tackled this subject and provided all the necessary information without trying to sell anything. Bravo!
Glad it was helpful!
I appreciate the kind words and support too!!
Yes you helped someone. I need to replace my coach batteries anyway so moving to LiFEPO4 is making a lot of sense. My coach is a 2001 Monaco Dynasty and the expense and effort to replace all the inverters, charge controllers, etc. was keeping me from jumping to the new batteries. Finally someone explained how to do this and removed my fear. Thank you. Now to buy the right equipment!
The best video on doing the important things when upgrading to LiFePO4 batteries.
I used the Li-BIM without trouble for 3 years, but switched to a Renogy DC-DC+MPPT this year. When the LiFePO4 batteries got almost completely discharged, they pulled >100A from the alternator/chassis battery. This tripped the 100A breaker I put between the Li-BIM and the chassis battery, so I could only charge from the AC-DC converter.
The Renogy DC - DC converter does 50A Max, and can be adjusted downward in 10A increments. It still charges the coach batteries faster than the Li-BIM, because of the on-off duty cycle of the Li-BIM.
The DC-DC charger products have improved a lot in the last 3 years. I don't regret buying the Li-BIM, but better options exist now.
Great job. Thanks for show how simple it can be. It takes the fear factor out of installing lithium battery's.
Thanks for watching!
You confirmed my hunch about using PV to top off the batteries as a more cost effect way on an older rig than changing out the perfectly good inverter/charger. I like the solution for the charging off the alternator. I might jump in now.
I have a 24 year old Georgie Boy 26 ft class A motorhome. I have been doing a major renovation and used AZ Expert's videos extensively when I completely replaced the roof two years ago. For the past few months I've been working on the electrical system. I kept the original house battery and engine battery but disconnected the house battery from the 12 volt house circuits and removed the original charger/inverter. This original house battery now serves only as a backup to the engine battery. Both of these are charged by the engine's alternator. To manage house power needs, I installed an independent 48v EG4 LiFE house battery that is charged via a Growatt 3 kw charger/inverter. Through the Growatt, the EG4 battery can be charged by shore power, by the generator, or with 800 watts of solar panels on the roof but not by the engine alternator. So when I am hooked up to shore power or running the generator, the 120v feeds through the automatic transfer switch to the Growatt charger/inverter. The Growatt unit normally routes the 120v directly to my 120v AC breaker panel. The Growatt also charges the 48v battery. If there is no incoming 120v, the Growatt automatically inverts 48v DC from the battery to 120v AC and feeds it to the 120v AC breaker panel. The 48v DC runs through a 48 to 12 volt DC converter, and is distributed to the eight 12 volt DC circuits in my motorhome. When I started the project, I expected it to be very complicated but was amazed at all the things the Growatt can do, and how much simpler it was than I expected. I'm not pushing Growatt over other manufacturers, it just happens to be the one I got, after seeing it on the Will Prowse channel and I'm sure others operate similarly. As AZ Expert mentioned, the electrical equipment available for RVs are getting smarter and thus easier to use.
Jim
You can re purpose your battery isolator to charge your chassis battery with the solar and never need to lock down the boost switch again I know you took out the jumper relay its just in case your new relay leaves the chat your solar will charge the chassis batterys. Just put the wire from the house batteries to the alt side of the isolator and number one to the chassis battery, it works great on my Monico. Keep it going. We all Love your work.
You are absolute right that LiFeP04 batteries are safe. But poor installation of LiFeP04 can. And many RV do have poor electrical systems that do not present a big problem with LeadAcid batteries. But install LiFeP04 and it can get dangerous. In my RV the cable from the converter to the batteries was not able to transfer the 60A to the battery. With lead acid not a problem as lead/acid do not accept higher amps for a long time. With LiFeP04 this cable got very hot.
Always install a T-fuse directly after the lithium battery. T-fuses have an interrupt current of 20000A. “Normal” fuses can weld shut. The BMS is just an on/off switch for protecting against under/over voltage and temp. It does not replace proper charging equipment.
You have answered many of my questions concerning the lipo4 batteries. I have opted to keep them on a Seperate Circuit. I can top them out with an eu2200i and ac-dc charger or solar power.
The Lithium circuit charges the Chassis battery via a trickle charger/maintainer.
This keeps them isolated from one another. Also have a 700w inverter on Chassis side for power on the Move which can also run the Ac/Dc charger for the Lithium bank so on arrival the Lithium is topped off with little to no strain on the Alternator.
By the way your Content is always appreciated Love your Videos and Knowledge. So much so I am now a Mobile RV tech 😂
my new favorite RV channel
Great video! A few points I think is good to make. If you buy a quality battery for the most part you don't have to worry about longevity of the battery. Most quality lifepo4 batteries will have charge cycles exceeding 3500. That means you can charge/discharge down to a reasonable percent (20% is usually the absolute lowest you should go) that many times and still see 80% of original capacity. Not charging to 100% will only make this number better. That means in 10 years your lifepo4 battery will still be 80% of what you purchased!
Also when selecting a battery make sure it has a hot AND cold cutoff sensors especially if you're in those climates. Lifepo4 doesn't like being too cold or too hot and will damage the battery, this cutoff sensor will prevent damage. Some batteries come with built in heaters that'll keep the battery above a damage voltage.
Either way, great install!
Glad I came across this channel, and I like the shelter setup....with the shipping containers and hoop canvas.
Excellent video. I think you have discussed all the important points. I have a 2022 class A on the F53 chassis. When I upgraded to lithium I spoke to Lion Energy and Battle Born techs and well as Victron. I changed out the converter, added a Victron DC-DC charger and changed my ZAMP solar controller setting to lithium.
Because I’m always concerned with electrical connections and shorts I paid a local repair shop here to check and confirm everything was good.
16 months later and everything still working great.
I truly appreciate your videos. Thank you
I installed the Renogy 50 Amp DCDC converter rather than that smart relay you used. The Renogy included a 25 Amp MPPT solar charger as well. If solar is installed, the Renogy unit will charge the starting battery from the solar panel after the coach battery is fully charged. It was very easy to install and configure. It doesn't required a start or run wire from the vehicle. It works great and absolutely limits the load on the alternator to 50 amps as opposed to the relay that AZ Expert used that has some voltage thresholds and time intervals. I just didn't want to load the alternator at 100 Amps.
How many watts of solar do you have and how many amps and voltage are you making out at from them? What size PV wire do you have?
That's my plan as well. I already have the a 40A DC-DC charger. 100A into a the right set of lithiums is probably low actually. The fact that these things do that for several minutes and then switch off.... I don't want that much stress on the alternator for 15 seconds, let alone 15 minutes. I'm an electronic technician. This is not something I would design for intermittent service. If you have to shut it off periodically because it's too much current, don't feed it so much current in the first place.
@@EliTuber Today I have a single 170 Watt panel that gives me about 7 Amps in full sun. So I can add two more of those before I max out the 25 Amp charger capability. I' used wire I had bought for another project. It looks to be 10 gauge? It's wire rated for outdoor solar panel use.
@@EliTuber Sorry, I didn't see this earlier. I had a single cheap 170W panel from Amazon. I could run for a few days before needing the generator. I recently installed a second 170W panel and that is awesome. The single panel would charge at 7 to 10 amps. I went with 10 gauge wire. Probably overkill.
You did a great job explaining. I would also remove the alternator charging rectifier and replace it with a smart one but install it away from the alternator and engine. Then when it gets hot or the amp draw decreases then it lowers the output or shuts down. if you cant afford a smart rectifier than moving it and adding a big heatsink will help keep it cooler. Heat as always is the enemy of electronics.
Excellent! This is the information I've been waiting for. Thought I would have to change / upgrade the alternator in my 2000 Beaver. Thanks James! You rock, buddy!
You're welcome!
Excellent video!
Answered all my concerns about replacing my Lead Acid batteries.
Thanks!
Thanks so much, James! My factory installed equipment was similar to yours on my 1997 Safari. I called Battle Born after purchasing my equipment from them.. I ended up setting up the equipment improperly and until I saw your video I did not realize it was not correct.😮 I won’t bore you with the details, but I just wanted to let you know you helped me get my system installed properly. I had previously installed a 240 amp alternator so I do not know if my original installation would have damaged my alternator over time, but I am thankful to have the equipment hooked up properly now.
Glad I gave a listen, my Foretravel MH has a switch to tie all batteries together for starting, not just a momentary Emergency start switch. I'm putting 2 of those liop4 batteries to replace the 3 8d gels. Never considered the Alternator limitations or the Em start solonoid issue you've brought to my attention. I have a portable 3-30-200 amp charger that I could rig to boost 200 amp for emergency start with the EM start switch instead ( generator running, shore power or inverter powering the portable charge/ boost) . Almost like a snake eating it's tail in the later mode. 😂 I didn't even think of the Isolator issue and the stress on the engine alternator. Guess that funny looking Isolator Amazon was offering me, without explanation, had some merit. Thanks for the video.
On the magnum, I believe you can just change the control head up front. The newer control head has the lithium profile.
That’s what I had to do on my 06’ Beaver
I used to have the same battery isolator in my 2000 Monaco dynasty. I went the DC to DC charger route on my coach with a 40 amp Renogy Unit and I’m happy with it.
James, great video on this much debated subject. Very clearly outlined as usual and simple enough for me to understand the steps and reasons for the choices. Thanks, PZ
Just wanted to let you know, that I absolutely loved your video. I thought I had researched lithium batteries fairly thoroughly, but I did not realize the charging issue. My system currently has 1800 amps of charging from the roof solar. And I'm charging 4-6 volt AGM batteries wired in series and parallel. These batteries are about 3 years old and I will be changing them to lithium at some point in the future. Thanks again for your thorough advice.
great timing, I was doing this build over the past 2 months. I just pulled 2 strands of 2awg through my van from the front to rear and through the rear floor. Next is to build some battery packs.
James, As I understand it, Magnum has a replacement panel for $250 that does have everything needed for LiFePO4 batteries.
Keep up the good work.
Yes, I have tried and had a few inverters not compatible so I didn't want to say it was possible.
Very helpful and informative video in layman's terms. Thank you for the time to make the video. Answers a lot of questions and concerns.
Great job. I appreciate your taking the time to do this. I was going to upgrade to Lithium when my supplied RV house batteries were 3 years old in my 2020 class A gas puller, but my WAFCO unit was not Lithium compatible. I considered buying an inexpensive standalone lithium battery charger and plugging it into the 120-vac outlet in the compartment where my inverter is installed and direct wiring to the house battery terminals at the input of the inverter to charge the batteries when plugged into shore power or when the generator was running, but it would not have solved the alternator issue. I was hesitant to do a DC-to-DC charger since it was something new to me (I am a retired electrical engineer but that doesn't make me an expert in these systems). Instead, I invested in two good 6 v Golf Cart Batteries which should last me about 5 to 7 years. Buying then from my Golf Cart center, I was able to get good quality batteries very reasonable. The two batteries were about $330. They will soon celebrate their second birthday and still aren't fully broken in.
I have installed a small solar system (200 W) on the roof with an MPPT controller and I carry 200 watts of portable solar panels in the belly of my unit with their own solar controllers to set up when I'm stationary for a while. Since we have a residential refrigerator and only 2 house batteries, we need to run the generator 12 hours a day to keep the batteries charged. With my solar, I can reduce it to about 2 to 4 hours depending on the sunlight. If I converted to LFP batteries, the solar would probably keep them fully charged so I wouldn't need to run the generator.
With the continued reduction in the price of the LFP batteries, I might be able to cost justify the conversion next time. That Precision Lithium Battery Isolation Manager is affordable so the entire conversion will probably be possible for about twice the cost of staying with Lead Acid Golf Cart Batteries.
We only boondock a week or two a year, so it is difficult to cost justify the conversion cost. With my current solar system, if I were to save 4 hours of gen time each day we boondock and we boondocked 14 days (we've never done that many), I'd save about 2 gallons of gas a day (we have a 5500-watt Onan gas unit) for about 28 gallons of gas a year which is about $100 a year based on today's gas prices. Of course, $100 per year over 7 years (battery life) does pay for it, but we have to run the generator 45 minutes a month anyway. We're not sure how many years we will continue traveling in the motorhome, so it's hard to cost justify much in upgrades if we won't benefit from them. If I do decide to convert, thanks to your video, I now have a path to do so.
Good video. I probably would have switch that signal battery momentary rocker switch to a off/on rocker switch and add a relay to ignition so ignition is disabled when switch is in on position while charging the chassis batteries. This way you don’t need pry something in the momentary rocker switch to charge it and RV can’t be started while the switch is in on position charging the chassis batteries.
AWWW, this is an excellent vid. I now know I can buy and realize an roi by replacing my lead acid with a lipo4 battery☺ using existing charge controller and inverter in my towable! I also, have learned I can reach a 100% by using a lithium charger connected to battery and/or using solar with lithium charge controller. Again, thank you.
I bought an EarthX LiFePo4 battery intended for experimental aircraft, it weighs next to nothing and seems to be able to crank over anything normal, so not a huge diesel, but, it’s limited to 80 amps for charging. I put SB connectors on it and on all my vintage Volkswagens, mowers, skid loader, and one on the end of half a pair of jumper cables. It works so good, no more having 15 batteries and 15 battery tenders and all these have small generators or alternators that are less than 80 amps, so working great for me. But it is a $450 little battery. Really appreciate this video, just about to start the upgrade on my Damon Tuscany for lithium and solar and really needing information so I can hopefully do it once, correctly.
Thanks for the information. I upgraded my class C coach battery to lithium a couple years ago. Tons of information online telling me I had to buy more stuff to make it work. I kept all the same stuff, only thing I did is change the monetary emergency start switch with a non-monetary one so I could charge the coach battery while driving. It rarely gets above 40amps. The lithium coach battery would not charge unless the switch was pressed. This video gave me some peace of mind. It good to know. what I’m doing isn’t too bad.
All good points you make. I went through this with my 5th wheel when adding lithium bats. Kept the stock charger knowing it can’t fully charge. Once I add solar I’d use the mppt w/ correct profile to charge or if I decide to add Victron multi plus 2.. my truck to trailer I don’t worry about it on the dodge as the small wiring limits the draw on the alt.
Your video is well done and thought out. Your common sense is refreshing.
Thanks you! :)
My LFP house battery install on my Triple-e Commander Diesel, I installed a time delay relay on the sense switch terminal on my DC to DC converter, and for my chassis battery maintenance I install a small 10Amp 12volt Trickle charger to keep the chassis battery topped up, I have a a Magnum MSH3012M Hybrid inverter charger (hybrid in you can supplement your shore or generator power with house battery inverter power, so say you have 115VAC 15amp plugin, and you turn on the Convection oven, it will draw the 15 amps from your shore / generator and the balance from the house battery / Magnum Hybrid inverter, truly awesome upgrade. My custom profile for my battery setting on my Magnum for Lithium is I use 14.6 on absorb, also set the inverter cutout to 11.8volts even though they can go down to 10VDC but that will initiate the Lithium BMS shutdown. I still have a Reliance configurable low voltage relay to prevent the house battery getting to below the BMS cut out but I have not installed that yet but might when I sell my coach. I normally ab bit anal when it comes to watching my power situation when dry camping, I have fun doing that! I am a retired electronics Technician and love the tech!
Wow! As an old Rver, this is interesting, I don't even still own an RV. But, I am interested in lithium for home us. I just came across Ur channel, very intertaning,
Great information !
I used the Renogy 50a Dc-Dc mppt charge controller, it uses solar first and then bucks up the alternator as needed. It can also be tuned back as needed.
Your videos are top notch !
Keep an eye on that Precision Circuits LiBim relay. I had one in my system, thought I could just run my house batteries down to nothing since they were Battleborn, what happened was the LiBim somehow got confused and in a closed state, meaning it wiped out my coach batteries also overnight. The problem I see with that LiBim is it tries to do too much with only a rotary contact inside. It can become confused, it clicks all the time and you really have no idea why. Finally I went with a DC to DC converter. I just didn't want my coach batteries and house batteries to ever be completely connected together again. Luckily I had enough solar to wait a few hours in the morning to start the coach by using the signal terminal to provide enough start voltage.
I also found an issue with this LiBIM. The name implies it will act as a battery isolation module and allow you to connect both batteries using a momentary switch. When the momentary switch is not on, the batteries are supposed to be separated, but I found this not the case. I found that my chassis battery was back feeding through this LiBIM after I shut off my house battery disconnect and solar disconnect. I found my victron Cerbo GX still had power getting to it from the LiBIM from the chassis battery. I plan to add a second battery disconnect next to the LiBIM to isolate the chassis battery from Victron components. This back flow only happens when the LiBIM timing circuit is battery connect position for active alternator charging. When timing advances to its rest state, the back feeding issue stops.
This is great information, I hadn't heard about this. I removed all other chassis charging setup to prevent them causing issues like this. I didn't like the idea of a dc to dc charger in this battery bay either as it is not weather proof and still has acid batteries too.
Now I’m having that same problem with mine. I thought there was something wrong with my battery bank. My LiBIM isn’t clicking anymore. It used to click about 10 seconds after cranking the engine now only when I pushed the momentary switch. For some reason my battery bank isn’t charging while driving any more. I have to spend some time troubleshooting.
Some DC to DC chargers like from Victron and Renogy are compatible with lead acid on one side and LiFePO4 on the other. Also some are isolated or shared ground. We have the victron on a circuit with a breaker for 3 years now on our Tiffin zephyr with lead acid chassis batteries and lithium house batteries and it works well, no issues and its customizeable and can be monitored through bluetooth on the app, and you can set a lot of parameters when to start charging, such as only on when the engine/alternator is running, and how your charging output would look too
@@davidlundy5007 Thanks for sharing, I haven't heard of this failure, but it sounds likeit may be more common.
One day when I break down I hope your around. You know your shit! I installed my system on my travel trailer and love Lithium batteries. I replaced my charger on my trailer that gave I think 30 amps with an inverter/charger from Renorgy. 3000 watts with a 6500 watts boost for 2 seconds and 65 amps charging for my 200 amps of Lithium batteries (small system but capable) Runs my tv and Starlink for 36 hrs none stop. Love my system and it gives me coffee and toasts anytime, without the dimming of lights as before with lead acid sometimes had to run the truck engine for a Keurig coffee before. I can start the air conditioner no problem and run it for 2 hours (current draw of 1200watts or about 100 amps). However I only run it for 30 minutes when stopping for lunch and it damn hot outside. Thank for the video, cheers from Canada!
My LiTime Lithium Batteries are fully charged @13.5 volts. They will absorb and eventually float to 13.8v daily. I use Victron Shunt and Network to monitor it and Victron MPPT to keep topped off everyday.
Really enjoy the graphs provided by Victron in the App.
James, thank you for this video.
We presently own a 2022 Winnebago class A gasser. Two years ago replaced the two lead acid coach batteries with BattleBorn. Installed a DC-DC charger, a new Progressive Dynamics converter-charger and reset the charger controller. The system works great but I always wondered with 200 watts of solar on the roof, did I really need to replace the converter-charger.
After seeing how well the solar charges the batteries, and after seeing your video, maybe I didn’t need the new charger.
Thank you for the videos. Very easy for the me to understand.
Thank you!
You did a great job !! I have pretty much the same setup. I removed my Big Boy and installed the Li-Bim.. I left the Signal Lead off. However, I did have to run a separate wire with 12v and fuse for the power of the Li-Bim. Going on 2.5 years and no issues.
Thank you for your very simple explanation about charging the Lithium batteries. I currently have a Xanterx Freedom 458 Inverter/Charger in my 2006 motorhome, I am hoping that installing the Lithium Battery Isolation Manager will allow me to charge while driving down the road along with the solar that I will be installing.
Thanks James. I'm on the finals step of doing the same upgrade on my 2003 Dynasty. In 30 minutes, you compressed months of research and in some cases misinformation. Just for a basepoint for others to design around I went for 2 batteries with a total of 600 Amp Hours powered by 4 panels totaling `1,600 Watts wired 2P/2S fed into a Victron MPPT 150V /100A solar charge controller. I removed the same 3 components (The battery booster, the isolator and the "maintainer"). I am in the process or adding the Progressive Circuits Li-BIM 225 Lithium Battery Isolation Manager even though I have a 200 Amp alternator. Total cost including tools, wiring connectors and Dicor was around $3,500 and can go 5 days off grid on sunny days without conserving energy.
As a note' Magnum Energy sells remote control panels with Lithium profiles.
Your coach is so cool! I live in bend where it was most likely built
Might want to make sure your bms can handle amps from the converter some can only take 50 amps these converters can be over 50
Three years ago I upgraded our '05 Four Winds class C Ford E450 RV house battery from a single SLA to dual 100ah AGMs. Not an easy job either as I had to build a second platform. I had considered Lithium at the time but cost then was more than our budget allowed and charging profile of our 45amp Parallax converter/charger seemed unable to correctly satisfy the requirements. Prices today for LiFePO4 types have come down to the point of the AGMs of 3 years ago so when the current ones are done I might just upgrade. The alternator issues concern me the most I suppose. Thanks for sharing as always.
Just upgraded to a LiFePO on out travel trailer after the deep cycle it came with died, I did use a LiFePO charger to charge to 100% before installing it, but the current WFCO doesn't have any LiFe settings.
I'm also adding a 3000W inverter charger and 460AH LiFePO battery, 400W solar this month for an upcoming boondocking trip.
Your videos on the LiFePO was very informative, dig the other videos across the other platforms too, keep up the good work & "Hi" from the west valley!
I have the same Magnum that you have, and it is fully programmable. I can even select a custom profile to meet my needs. The programing is done at the ME-RC50 remote. You use the custom profile in the Setup page.
The problem with not getting to a "full state of charge" is that most of the sealed drop-in batteries do their balancing by having the BMS charging FET's turn off at 14.0v and then use the voltage above that to do passive balancing while the cells are really not being charged other than by the balancers at 70-100 mA. I checked the specs on your battery and that is exactly how it works.
If you do not charge to more than 14.0v, you will get no cell balancing and that will cause the cells to drift out of balance over time.
As mentioned in the video, James' rig has 600 watts of solar for the full charge.
This is the first I've ever heard mention of fear of fire. I made the switch 2 years ago to lithium batteries and it was the best decision I ever made just got a new travel trailer this spring and switched it over to lithium immediately and now 100% off grid for as long as i want
James, you look to be doing well. Seems like a lifetime ago we worked at LMRV!
I'm suspect of that Precision Circuits unit. Seems a few commenters are having issues with it.
My first concern is the size.
It may say it's rated for continuous 225 amps, but I must question that. Any solenoid with a true 225 amp rating is quite a bit larger. Thus disapates more heat. 225 amps can generate a lot of heat. That is why those diode isolators went ot of favor. They could get quite hot and the RV builders rarely had them mounted in a location to get decent airflow.
Anyway, my 2 cents worth.
Happy Trails!
Nice video, this subject has been coming up a lot lately on the forums. I did this conversion on my 97 Monaco Dynasty 3 years ago. Built my own LiFePO4 battery and used a bluetooth BMS with it so I could monitor and control charging, charge states, etc. from my phone. In my case I went with a Renogy 60A DC-DC charger as I wanted complete isolation and reasonable charge rate, and the cost was low (on sale). I connected the oem 80w solar charger (non MPPT) to the chassis circuit to keep my chassis batteries topped up.
I just wanted to point out that if you are using an converter/charger that doesn't have a lithium charge profile, and thus you may be using less than full cutoff voltage for the batteries, it is a good idea to occasionally charge using a charger that DOES have a lithium profile, either a solar charger (as in your rig), or a DC-DC charger (as in mine). The reason for this is that the BMS will do cell balancing during the charging, and the most beneficial period of time for this is in the upper "elbow" of cell voltage, which you may not achieve without the lithium profile. Over a large number of discharge/charge cycle the capacity of the battery could be lessened if the BMS isn't able to keep the cells in balance.
Keep up the good work and ignore the naysayers, LiFePO4 house batteries are a game changer.
Great set up. Don't over think it. Words to live by. Thanks for the video.
Thank you for the very helpful information about using the older converter/charger on my travel trailer with a LiFePO4 battery. I had deduced, based on vague comments on other sites, that it would work but not give a full charge. Thanks for confirming that. I will stick with the onboard unit for now and use solar as described to "top off" the charge as I hit the road for the '24 RVing season.
Magnum inverter/charger can fully charge lifepo4 batteries. Capability may depend on model etc. On my magnum I use the constant current constant voltage profile.
There are some magnum inverters that support lithium charge profiles, you just need to make sure you have the right display unit. I swapped out the existing ME-MR25 for a ME-MR25-L for a 150 bucks. You need to make sure the ME-MR25-L has version 1.3 on it to get the Lithium charge profile. My existing unit had version 1.2 software.
Great info, thank you! Please cover cold weather and charging at some point. Do I need a self heating LI battery?
Depends on your application mostly, I don't like cold camping so it's not something I worry about. Many batteries have the option, or you can re-locate inside a more heated bay which I would recommend to minimize battery complexity and wasted current draw for the heaters.
Thanks much!@@AZExpert I'm thinking of this swap for my 2019 Tiffin 37 PA.
Thanks for the Update, James !!
You bet
😅 On cranking amps to start 25:59 the engine! Thank you for your alternator protection tips as independent of the BMS. Question about the temperature you are running through your upgrades. I am concerned about running solar in colder temperatures where the volts from the solar panels are higher than at 77 degrees.
I have solar and a new converter.
I found with 500w of solar and 400ah of lithium battery I would still run low after 3-4 days in glamis. Particularly if it’s cold and I need to run the heat a lot. Or it’s cloudy.
I installed an 80a lithium compatible converter and now I can just run the genny for an hour or two and juice them up pretty good if needed. New converter sends 30+ amps to each battery, whereas the factory one would only push 5-8A each.
Thank you for addressing my question about the Li-BIM. I've been contemplating whether it truly protects the alternator. I'm preparing to upgrade my Class C motorhome.
Very nice video thank you...now I have a question: according to the wiring diagram for my 22 Jayco Alante 27A, the generator uses the house batteries to start the generator (an Onan 5500). Will the LiPO4 battery be able to get that done? Or will the generator require more than the 200A my LiPO4 battery will put out?
Thanks for the video James
I have a 1998 Patriot that is set up like yours with the echo charger and the boost solenoid. When Vatrer put their 460 ah battery on sale I decided to copy your installation.
I replaced 4 6V GC batteries with the Vatrer, took out the isolator and echo charger, disconnected the boost solenoid and installed the BIM.
Everything seems to work fine and the battery initially charged to 99% SOC. Now it has dropped to 75% SOC and it is not charging even though it is plugged in. I am guessing this is the BMS keeping it from charging until it gets to a low enough SOC.
My problem is the chassis batteries are not charging when the house batteries are not charging so they are getting low as in 11.8 volts. They will charge if I hold down the battery boost button.
My inverter is a heart freedom 15 and I set it up to charge at 13.4 volts with the dip switches.
Are your chassis batteries being charged enough to avoid a low voltage situation? Do you know of any way to isolate the chassis batteries and charge them seperatley? Thanks Carl
thanks for the info on emergency start switch. I have a trailer now with Lithium batteries but in the past had an old Class C which I remember that button. I will keep it in mind when eventually move back to a Motorhome.
Can these batteries provide sufficient power to start the generator? I believe some types of batteries have current limiters built in.
Thanks for the detailed info, my friend is looking at a 22ft. 200k coach but has acid starting and agm coach batteries and I was going to suggest lipo4 instead but for simplicity's sake I'll leave it alone.
With my trailer I disconnected the charging wire from the seven wire plug. My solar charges the batteries as I drive. Don't want to burn out the alternator on my truck.
Pigtail doesn’t pass that much current my lithium only pulls like 3 amps from the pigtail
Panels not aimed at the sun produce much less charge and of course clouds don't help. Weekend warriors obviously don't need these considerations.
This is great into. Thanks. I want to do this with my yr2000 Dutch Star. My Charger inverter are pitiful now so may upgrade that, to something like a victron 3000. My fridge is still elec/gas and works great. But if/when it goes with go to standard 110V. Again, thanks for the well laid out info. No not super detailed but much more than I know before!
Awesome job on the video James. Well put together and very informative.
Glad you liked it!
I carry the largest Noco boost pack with me. It’s probably the best stand alone jump pack you can have when you are out camping and may find yourself unable to start your rig.
Nice work. Another thing to consider is which battery bank starts the generator on your application.
As you discovered the Li-BIM 225 is bidirectional which directly connects a Lead Acid battery with a LiFePO4 battery system, with charging current flowing either way (not good). A likely scenario is that a heavy load is shut off on the chassis side (starter off) while the Li battery voltage is low (isolator connected) causing the alternator to give massive charging amps to the Li battery. The isolator can't react fast enough to disconnect because the Li battery is pulling down the alternator voltage below 14.4v. The specifications on the Li-BIM 225 allows 1200 amps for up to 30 seconds. Therefore the Li battery BMS will isolate the Li cells as amps exceed the maximum for the Li battery. When that happens, it is like pulling off the battery cable from the Li batteries at maximum amps. The voltage spike will cause the alternator diodes to fry. This is called flyback voltage. SInce the Li batteries are isolated by the BMS, there is 0 volts on the coach side of the RV now. The alternator sees a load of 200-300+ amps, then 0 amps. What does the Li-BIM 225 do now? Everything is off. You now have to manually reset your Li battery and diagnose the red alternator light on the dash.
As you can tell I don't like this system. What these companies don't tell you is what happens when the BMS isolates the internal cells of the LiFePO4 battery. It is not predictable - massive load to no load instantly.
So what do I like? A DC to DC charger that always gives a proper voltage and amps to the LI battery so that the BMS is never going to see voltages or amps that will trigger an isolation event to the battery. It will never overload your alternator and the wiring is as simple as the Li-BIM 225. To charge the chassis battery from the Li side I just use a trickle charger powered by the inverter, but if you have solar (I don't) you don't even need that.
I really love your channel and what you do, so please don't take this critically.
I appreciate the information and comments. I think there are many scenarios that could be imagined, even dc to dc could fail, I am not sure I follow your situation completely. From my prespective, damaged alternators is already a more rare possibility with LiFePO4, but adding a dc to dc and battery tender has increased complexity for most DIY and technicians. Most Frieghtliner chassis already have a ECU controlled circuit which cycles the rv charge solenoid if chassis power gets too low, and for over 20 years, these BIRD systems have cycled thousands of times connecting and disconnecting every 10 seconds to one minute as the loads cause spikes to the alternators. The Libim225 just changes the parameters slightly
LiFePO4 is also sometimes abbreviated as LFP. These cells like to be kept at 100% all the time, which is the opposite of what NMC Lithium Ion cells like, which is about 80% charge unless you need to utilize the full capacity for a short duration. This topic has even become an issue with Tesla, which recommends the 80% setting for NMC models and 100% on their LFP models. In fact, they recommend charging to 100% at least once a week to maximize cell life. Really great coverage of the topic, James, it's much appreciated. There are far too many myths and similarly few down-to-earth discussions of the topics you mentioned.
Well, yes, LiFePO4 doesn't mind being charged to 100%, but that isn't why Tesla wants people to charge LFP vehicles to 100%. The reason is simply that the charge curve is so flat for LiFePO4 that the BMS / shunts / whatever monitoring you have for battery state of charge, can't keep track of the state of charge accurately unless the battery is charged to 100% every once in a while.
For Tesla this meant that the vehicle was unable to accurately calculate the remaining range when people only charged to "80%" (which itself is a guess by the vehicle because "80%" is still in the flat part of the charge curve)... and sometimes caught people out.
The main issue for longevity is to avoid discharging the battery all the way to BMS disconnect very often, and in particular a lithium battery (of any type) should never be left completely discharged for weeks or months. That will destroy the battery.
Thanks for putting that myth to rest. Many UTube experts still put that 80% bs out there.
Even though 100 Amps is a lot to draw from the alternator, the LiBIM225 only connects for 15 minutes, then disconnects for 20 minutes, and cycles like that when in charge mode.
Excellent video James I'll be watching this over again. Lots of important info thankyou!
Thank you, I am going to switch to this in my 2007 Winnebago tour.
What about Starting the Generator like Onan ?
Mine is started off the chassis batteries
Mine uses the house batterys
@@AZExpert If you start with the engine Batterym wont that drag the batter down, as it does not charge the batter?
@@talk2hubba the isolation relay I installed is bidirectional so if the house are charging it will charge the chassis
@@talk2hubba yes, it has a small draw while running, but the relay I intalled is bi-directional so it does charge the chassis when gen or shore is chraging too. Otherwise, I'd likely just connect a permanent battery tender to the chassis batteries
Idle current capacity of your alternator is KEY. It will do full output at idle.
If you dont rev up your motor you will typically not get you rated output current. It will overhead. You NEED the fan speed.
And burn up your alternator.
And like he said that truck pigtail will not carry current you will need on a depleted lithium.
Another good education video, covering points people miss. Thank you
Thank you for the video. I think you did a very good explanation of all the parts. God bless you and yours.
I put this on my Class A. What I’ve found is the cycling of the charge causes my chassis battery to connect and disconnect the alternator output often. Mean I park, RV running, and when I open slides the chassis battery voltage goes between 12.7v and 14.4v every few seconds. Kind of surges while opening the slide.
Found the Onan Generator use about 100 Amps to start. So can i use it to start with 250 AMP BMS?
I went with a Renogy Rego DC-DC which is bi-directional, not a fan of the Li-BIM cycling it relay at high current every 15 minutes vs DC-DC regulating with semiconductors. Plus Rego can buck/boost voltage where BIM just connects both sides at same voltage. Wired a dumb Cole-hersee in parallel connected to dash switch for emeregency boost.
I'm also not of fan of the cycling BIM. It still puts significant load on the alternator and my existing BIG BOY w/ Bird controller isolator works just fine. So I went with perhaps the cheapest solution for my coach and just connected the ignition signal to the unused GENSET input on the bird controller. This has the effect of opening the BIG BOY relay anytime the engine is running. Basically I don't want my alternator charging my big bank of Lithium's at all. I have enough lithium capacity to easily run the entire coach loads on my longest drive and if for some reason they were low I would just start the generator while on the road to charge my Lithiums. I've been running this way for several years with no issues.
Put a lithium iron batt in my motorcycle in Phoenix, AZ and was in the for 4 yr. No problem except it did not like to start the bike cold, had to leave the light on for a couple minutes to warm up the batt due to current flow. Expensive but much lighter.
That's interesting, I generally don't like lithium for starting engines but I could imagine weight savings is important on a bike too.
Solar is indeed the way to go. I have a 2004 Tioga class C with two residential grade solar panels I installed on the roof. A 310 W panel drives an MPPT charge controller for a 100 Ah lithium battery which runs a 2000 W inverter for a two-outlet branch circuit I installed in the coach independent of the coach AC shore power system. It provides all the power we need for the coffee machine, microwave, toaster, and TV. When we're not camping (which is most of the time) I disconnect the solar and charge controller from the battery and let it sit idle for three months at a time per the manufacturer's advice for maxing out battery life. I also have a 255 W panel driving another MPPT charge controller for the two lead-acid house batteries, which I'm going to replace with a 100 Ah lithium battery. Rather than worry about converter and alternator compatibility, I'm just going to unplug them from the new battery. If the solar doesn't keep up with the DC load then I might have to rethink things, but the RV has a generator which we never use and we do a lot of dry camping and have never run low on battery power with the lead-acids, so I'm hopeful that this won't be an issue with the superior lithium battery.
I took out 8 lead battery's {all rv Battery,s }then put in 4 lpo 12oo amp hrs with 1150 watts solar also change alternator to BALMAR CONTROLLED SYSTEM .Now seven years later everything is fine.when I did it I was the only one in us to do this,no RV manufacturer did this or would do this.
Great info, just clarify the 14.4+ volts are needed to balance the cells. The BMS will not balance the cells completely without a top-off voltage. You are correct that you can use lithium on a standard system. However, this will degrade the cells faster than normal. You had some great recommendations on how to handle the top-off voltage. solar being one of them or using the alternator system in a motorhome. almost all converters that have been made in the last 15 years can output 14.4+ volts. It’s usually either some kind of jumper wire that looks like a telephone plug or some kind of smart controller that also uses an RJ-45 jack. Check with the manufacturer before you buy new equipment.
most lithium batteries don't want to be charged at 100% all the time so undercharging to 80-85% will not damage them, BMS keeps cells balanced while charging too
I would check with Magnum about that "Equalize" setting on with your Magnum Inverter/charger. The head tech guy at Magnum told me on mine that it should be set to off.
But also check with your lithium battery manufacturer.
Same questing to Magnum but I was advised to set “equalize” 14.4V and program it not to come on. But if it did, it would not cause any problems.
That sounds like plan. Mine is just set up.
Wow, someone that knows what they are talking about, perfect information, I have see so many people on boats/yachts that think they can up the alternator to 200 amps only to find out they are lucky if they get half that... maybe some day when someone comes out with a water cooled unit and separate voltage regulator... I used to wind by hand electric motors for electric vehicles, and I would tell people the motor will be drawing 50-80 amps in cruise, meant nothing to them... A 100 amp hour battery will not supply 100amp hours, I could go on and on about this.... clicking on my name will take you to my utube on motor winding stuff...
Thank you, the first video answered a lot of questions I had, but your second one confused the crap out of me. I have been waiting to install lithium but I have been worried about the alternator issue. Your test meter showed too much voltage going to the starting batteries I think, won't the solar boil the lead acids, your meter also showed the house and starter batteries linked in the lithium was charging the lead acids, won't that cook them ,
Thank you once again this is a hard issue for me to wrap my head around also wasn't that one unit you removed for linking the batteries when your starter batteries were dead.
Our 2003 Newmar Dutch Star D.P. has 2 IOTA 45 amp charge controllers with a phone jack system receptical in the side that I can get a plug that plugs into it and it changes the charge profile to one for lithium batteries.
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Exactly all the details the other lifepo conversion videos are missing! Thanks, subscribed! Am I missing something or can't you just switch off the house batteries before and during engine operation to protect the alternator?
Thank you. Yes, you can turn the battery off with the app but then you would lose 12vdc house power
@@AZExpert Thanks for the reply. I'll have to see what outlets/appliances are on that. Might not be a big deal to lose house power when travelling. We've also got a mechanical toggle switch up front that does the same thing. I'll have to see if that also prevents alternator charging. We've got solar direct to the battery, so if I can leave the battery on with the app, but shut it off with the switch, it'll still be getting a charge at least.
Completely different scenario, but, I ran yellow tops in my boat for about 12 years. The same yellow tops the entire time. Last year I started to notice I could only get about 3/4 of a days worth of trolling from my batteries. They were finally dieing off. Slowly but surely.
Those yellow tops were given to me from a guy I know who drives a KW for a living which had a climate control system installed that ran off of those batteries, 4 of them, and he switched over to an APU and GAVE me those batteries. They run about $300 a piece.
So for the same money, I bought 2 LiPo4 lithium iron phosphate batteries. 100 amp hours each. The yellow tops weighed about 70lbs a piece. I was utilizing 3 of them, 2 for a 24v trolling motor and 1 for a 12v radio, then I still had the original starting battery, also a lead acid battery.
The new lithium batteries weigh 35lbs each. BIG difference. But, I can go 3 full days of trolling on them without recharging and still be at about 35% on the batteries. They are amazing.
That being said, I did have to buy a new onboard charger that could handle both types of batteries, a 4 bank charger which was an additional $350.
But for a guy like me, who spends as much time as possible on the water that I can, I don’t think I’ll ever go back to the lead acid batteries. The up front costs will be gained back over time, they weigh at least half of lead acids, they deliver way more power for way longer, and are simple to maintain. Plus, I don’t have to keep my onboard charger plugged in 24/7. Just long enough to charge the batteries then done. Well worth the money, just have to be careful WHO you buy from.
I think you are right on the money.
James, great follow up, thank you!!
Glad it was helpful!
James, excellent information! I have two questions, with my fiver, did I understand that I really wouldn't have to add anything to it switching to the LifePo4 battery just that it would only charge to %90 capacity? Also, is there an issue with going to 2 - 230 Ah vs 1 - 460 Ah as I would save $400? Thanks for all you do in helping us RV'ers.....Kindest regards, Ted
For a Class C or smaller, just get a beefy portable lithium battery jumper. Always handy to have around, as you can give other people a jump without risking your own electrical! They usually double as flashlights and USB power banks, too.