Prismatic LiFePO4 cell prices have once again come down. Even with the wide-spread popularity of cheaper-than-ever, commercially-build lithium packs, you can still build your own for a lot less. I mean like 35% less and with all of the high-end features such as low-temperature cutoff and Bluetooth app connectivity. In this video, I will show you how I built a 280A pack for less than $700 and where I sourced all of the parts. Buy 280Ah LiFePO4 Cells from Shenzhen Qishou Tech www.alibaba.com/product-detail/Grade-a-lifepo4-3-2v-280ah_1600551390417.html?spm=a2747.manage.0.0.73e871d2RVwOMi Buy RadioB Tech 120A BMS: amzn.to/39OYgYA My Preferred LiFePO4-Compatible Smart Charger: amzn.to/3A2eeJq
I am a very novice LiFeP04 guy looking for the best, most cost effective solution for my needs...This video was excellent...How many cells can you actually add to that BMS and it still work? I have a truck bed camper and want to max out the AH for the space I have available. So can you build a 400 AH battery this way, using the same parts, just more cells? and do you have any other forums you are a host/member of that i might be able to sign up for?
This guy is awesome, thank you so much for sharing. I used to buy a lot of ADCBATT 100ah lifepo4 batteries and although they are not expensive and still work, I plan to make one myself.
I thought that the cells from Ali express were b grade junk? I’ve heard several people never even got their batteries. Now, these were complete batteries, not cells, so maybe it’s different?
@@robertboyer5498 AliExpress is a platform with thousands of independent sellers. So the quality varies from each one. You can not blanketly assume anything across all of them.
Thanks for taking the trouble to share this. I dropped over 1500 UK pounds on drop-in batteries for my last boat, and on my current project decided to take the smart way and build my own pack. Just yesterday I got my box of Eve 280 cells and a good BMS, and am just getting started putting it all together. I had already got it pretty much all figured out, but it was great to run through it all again, and especially to pick up hints like the plastic between the cells and the issue of heating from the BMS. Well presented band clear. Top stuff.
Nicely done, straight forward, simple to follow by design. Thanks for sharing the education. I’ve got 16 cells 100ah that need a Bms to construct either a 12, 24, or 48v battery. This has been very helpful in understanding what needs be done to continue. 👍🏼
I have been using similar batteries to these as almost my only source of power for nearly 4 years now, all done from youtube videos like this and zero experience. The price to performance has improved so quickly in that time, roughly 40% more capacity for the same size and weight for less money is incredible.
people should not be afraid to try this, I really appreciate those who will encourage diy crafting. Some of the direct replacement options are total crap and unless you are willing to cut them open and see what is inside you have no idea what you have bought.
If you are not afraid you should try. If you are, you should not. I've seen too many poorly constructed electrical project built into moving vehicle and enough fiery inferno as a result to think everyone should do it. There are more than enough budget yet high quality batteries out there. Just buy a name you recognize and you will be fine.
These batts will probably be lower in price over time. The other facet not mentioned in this video is the ability to add more cells either in series or parallel. Either changing the bms or adding another depends on how you wire. But these are a great starter with budget in mind which can be increased over time without tossing any you've already purchased. 16 in series give you a 48 nominal volt setup which requires smaller wiring for the same watts used. The versatility is just wonderful.
Thanks for the concise video... One comment: The cell sense wires of the bms CAN be cut, there is no way 20ga wire, at .01 ohms per foot at 3,2 volts, with virtually zero current draw, is going to have any voltage drop. I notice nearly all the DIY builders think the same way, which tells me they all watch each others channels. The instrument doesn't have close to the resolution to read any difference. Simple ohms law for voltage drop. It would be microvolts
Of course it can be cut practically speaking. But when you make a video showing people how to do things, you need to teach best practices. The best practice is to not shorten them. There might not be a measurable difference but there is a difference at least in microvolts.
Hi Dan, BTW The 280K is the 6,000 cycle battery from EVE as the 280 normal is 3 - 4,000 cycles. Best charging the batteries in parallel to connect the positive at one end and the negative at the other end of the battery bank. This will avoid the first cell in the line taking the most current and last one the least. If you get a chance to try the JK BMS it is the best on the market according to me and Off-Grid Garage on TH-cam. André
What do you like about JK BMS? Active balancing? And you actually believe what Andy says over there from his broken shack down under?!?! Just kidding 😂 He's making some good content over there.
@@freelyroaming Yes the active balancing is the main difference. It is fully featured and seams to be very reliable. I was commited to package deal with a DeliGreencs BMS new parallel version so I could not change. André
There are a few things you should take care of, apart from not assembling the battery on a steel table. Don't use an adjustable wrench to tighten the nuts - it.s too easy to accidentally creating a short circuit. Use a socket wrench instead. Don't use scissors to cut tie-raps but use short snips (with insulated handles) for the same reason. Do not tie-rap all balancing wires together, if there is any damage on the insulation of the wires you may get fire or at least smoke. Do not tie-rap the C- and B- wires in one bundle - if they short circuit you are disabling the complete BMS. Never ever use those large heavy cells wrapped in just packing tape. It's too easy to get a puncture in the wrapping or denting the cells. Also, follow the manufacturers specifications on how to mount these cells. I've seen manufacturers specifying that you must compress these cells to make sure they cannot bulge, resulting in de-lamination of the cell. How do you think these are EVE cells? EVE is a brand with a well known reputation so anyone selling EVE cells will leave the EVE label on the battery or at least have their own label with "Manufactured by EVE" on it.
You should watch some more of my videos before making your critiques. I've got plenty of real world and technical experience building off grid electrical systems. 'Not my first rodeo' is the common expression .There is plenty of other videos showing how I've built packs that I actually use. As I stated pretty clearly in the video, this was not meant to be a 'best practices' build video. It is just to show how components go together which was something requested by subscribers. And for a non-mobile setup, there is zero risk of insulation rubbing, chafing and shorting. As a full time traveler who does a lot of DIY projects, we don't have the luxury of a workshop full of tools. Learning to do with what you have is a very useful skill. It is all about understanding and assessing the risks and make it work with what you have. I assume you just landed here from TH-cam recommendations without knowing other already posted contents my channel. There is one all about cell compression as it sounds like you might learn a few things from it.
WOW, nice and simple build one of the best to be honest and straight to the point, and yes LifePo4 batteries are the best I am glad you went with the Eve brand as I have heard a lot of good positive feedback from other folks too, thanks for sharing man, cheers.
this was fascinating but i disagree about one thing, i would definitely put the BMS on top. Put it on the side and it's vulnerable to squishing or impacts, but on the top it's protected somewhat by the + and - terminals. And i would cut the sensor leads (and the ground leads) as necessary. Because the input impedance of those sensor inputs is quite high. That means that those leads are not pulling any real current and so cannot drop a measurable amount of voltage no matter how long they are. I noticed that in the menu settings the balance precision was set to 30mV. The voltage drop on those leads is much less than 1mV. Great work though, thanx for posting.
Thanks. There are lots of pros and cons to how to build a simple pack. Doing what makes sense to you is what is important. This is just meant to show the easiest, no frills build so that more people can understand how they come together. Thanks for watching.
i just bought a 304ah with heating for 1700 euro, it just has a JBD bms and eve cells - i know this costs only about 5-600 euro so its was hard to swallow, but it helps a local guy out and i dont have to think about it, i think next time in 10 years or so I will build my own.
Nice video. One item that you should consider doing is to connect the main negative load leads directly to the battery terminal, then attach the balance lead on top of the load leads. That way the load leads have better contact with the battery terminal and the lug for the balance lead is not carrying load current.
He's talking about the stacking order of the ring terminals on the lug. It's not really that critical for off grid power use but for high current draw applications like EVs it might help. But even then it's not really gonna make any noticeable difference. Just best practices kinda thing.
That's why I used. Although it's really not likely to reach any temperature hot enough to cause the adhesive to fail when this is used in an low c rate environment.
Thanks for sharing the knowledge. As right now, you can buy Chins 300AH around $970. I don't see much of the saving because the cost of 4 cells 3.2v is $750 + $130 BMS + bluetooth.
If not a lot of savings you will have more features like low temp protection, Bluetooth connectivity, smaller footprint and most of all, ease of maintenance. This for me was less than 700 bucks all in. I don't know about you but that's more than 300 bucks cheaper than Chins using my math especially when factoring in tax.
Thanks , very educational for beginners. Very good video compared to others out there. You stressed safety which is very important but safety glasses and at least sunglasses should be worn at all time working on battery like you did. No metal when welding or electrical work period.
Hi, since Im taking a deep dive into renewable energy, I understand there is a cost saving in a DIY version of a battery vs buying a LiFePo4 battery. My question is the following, how big or small is the safety concern of a daily use of a system built DIY vs just buy a portable solar generator system with a battery bank integrated in the same compartment like the Bluetties and Jacakrys? I do like to tinker with stuff, and you made it look fairly easy to build that 280AH battery. That motivated me to think in building a system.
Experiencing pain, seeing a bright yellowish-white flash of light and smelling my burned skin helps remind me to wear gloves from now on. 13V is enough to travel through a slightly sweaty skin surface. God saved me again. Aloe Vera gel is the best of God's creation to cure burns.
You always have to specify Ah along with the nominal voltage. Each cell is 3.2V at 280Ah which makes 896 Wh (3.2x280). When you connect 4 of these cells in series you will increase the voltage but the Ah rating stays the same. So the full pack will be 12.8V at 280Ah which makes 3584 Wh. Watt hour is a much better way to describe battery capacity because it can be stated alone without any other specifications.
I started with these exact batteries, built a pack of 16 in series @ 48v, I'm now building my 4th pack with a combined 57,344wh pushing 2 6500k inverters, and everything works great.
Great information will help me greatly deal I'm goin to make battery pack to charge on off peak electric @ night to use during day giving me 24hr off peak lectricity shud save a great deal with big rise in energy prices, think l need to aim for sbout 10kw to run bungalow in day! Don't think l should have any problem putting that together, I'm a retired electronics tech! Just hope l can get all stuff you got shipped here to U.K. very good presentation lot good information thanks so much saves me time on researching all this myself!🤗🤩😎🌹
I have a sailboat, the battery box will barely fit a group 31 batteries and at most I would be able to fit 2x 100ah batteries, so 200ah would be my limit. However, looking over measurements, I can fit 8x 280ah cells giving me 560ah. It doesn’t take much convincing that I don’t really need a case or a battery that looks like a battery because that’s more “acceptable” to most people. I’ve watched tear down videos and it’s nothing but foam and air, so it’s useless to me, I want the ah rather than the looks.
Cut the wires, the BMS has next to no current when measuring so therefore no voltage droop. Also when top balancing no need to wait when first connected but when charging leave at 3.65 for a few hours.
Correct me if I'm wrong but last time I checked, red was positive and black was negative. You appeared to have connected the blue bms negative leads to the positive terminal on the battery pack. Just an observation
I live in Canada. Any chance you could recommend a BMS with same features but also able to accommodate heat pads. Appreciate the tiem and effort you put into your videos.
@@lyndsaybeck2249 use an active balancer (aB) for your 100Ah cells. They have much more precisious performance then such types. You configure only the cutoff voltages (2,5Vmin / 3,65Vmax per cell) in your inverter. The balancer manage the cells until 0,001V difference. An aB produce no heat and your system has no powerl loss! negative: aB have no BT and Apps if you want present your cells your neighbour ....
Great video thank you. For your BMS and heat issue, why not place a thick sheet piece of silicone from a cheap silicone pot holder. Also did you have to pay $110 shipping per battery?
Nice work! Why was BMS chosen for a maximum current of 120A? It's only 1.44 kW. Is this power enough? Your battery can give much more, at least 2 times. For example, 200A (power = 2.56 kW) or even 250 A (power = 3.2kW). What is the basis for choosing a BMS with a maximum current of 120A? Thanks for the answer!
200ah 12v lifep04 from redodo are 459. shipped and i even got a 30.00 amazon coupon so it was 429.00 kinda hard to beat, i am running a pair of them in series with my 3kw powmr all in one inverter for my camper.
200Ah Redodo doesn't have low temp cut off. For $469 you could have gotten a Golden Mate 200Ah that does like this diy kit. Running 2 of them takes up 3 times the space for someone with a smaller camper.
@@freelyroaming I had already watched a review on the redodo 200ah .. and understood that it had only a high temp cutoff. i am running a 18w warmer with auto thermostat it will cut on at 50'f and cutoff at 70'f (made for a chicken coop) since i am setting up inside a externally accessible storage area .. it looks to be the ideal answer to keep the batteries warm.
No they don't do TH-cam. We actually just spent a day with them last week. they have been living in Colorado while their son goes to high school. He was out here on California visiting college campuses.
Hello, I've seen a few of your awesome videos and am now hoping to get some advice. I'm new to the battery / car camping scene. I plan to keep an Amazon LiFePO4 battery (maybe 2) in my car as a power source for a Dometic fridge, lights, laptop, etc. so I can live in my car on the weekends. I'm still shopping / researching so I wonder if Group Type matters, mixing battery / inverter brands or things like that matter? I want to charge the batteries at work then bring it to my car and shelf in the cabin with me. So far it sounds like I'd need the battery, and an inverter. And I think I can just plug a power strip into the inverter? Do you see any issues or have any advice for this type of use?
How does the battery charge on negative? You leave the negative bms wires "hanging?". Huh, interesting. I would have thought you would be connecting loads directly to the battery but i guess if the bms has protections it hzs have to have the current go through it
That's correct. If you connect directly to battery negative, it would work of course but you would lose all of the protections of the BMS. Because this is a common port BMS, it means it charges and discharges from the same negative port. The protection schemes apply to both charging and discharging so you never want to connect anything directly to the raw negative battery post besides the BMS.
@@freelyroaming That makes sense now. Thanks a lot for making this video! It looks pretty straightforward to build this. That's a huge battery ! 4Kw of energy for only $700ish, wow
Well actually...... 🤦♂️ I've already addressed this in other comments. The wires can be placed anywhere on the bus bar that connects the positive of one cell to the negative of the other cell. You get the exact same reading.
Nice video, Im thinking about building one myself and took contact with the reseller you linked, so did you have any problem with them and Cassie Wang there said it would cost 560$ with shipping and all to Europe. So you think that this is a good price or should I wait?
I'd like to build a 36 volt 100 amp hour battery for my 36 volt ezgo golf cart. Any suggestions on components would be appreciated. Thank you, great videos !
I did this set up with just the 120 amp bms. I have a 40 amp. Rich charge controller and two 200 watt. Panels. Also 3000 watt pure sine inverter. I have been all over the app and can't get my cells to charge past 13.4. I put my Noco genius 10 on it with the bms hooked up and I only get 13.4 and only 3 out of 4 red bars on the charger no matter how long I wait. When I charge the cells without the bms hooked up, I get 14.4. Then, as soon as I hook the bms up it takes it down to 13.4. I have calculated about 50% capacity. Maybe less. The only thing I can think of is the bms needs to be a 250amp? Advice would be perfect. Maybe parameters I need to change? Thanks
I've ordered cells from Shenzhen Qishou (QSO) manufacture but I have concerns. Now that iIve found your video, how do these QSO cells perform, two years on? Are they worthy?
32V battery build. On my boat I have 2 banks of 4 8V lead acid batteries that I would like to replace with IiFePO4. Each battery banks is independent for port and Starboard motors. Currently I also have the 32V inverter connected to one of these banks. Having searched the internet I quickly realized this will be a custom battery made from cells like in the video. I can find 32V 10S LiFePO4 BMS units. The difficulty I'm having is can I use the same battery bank I make to start the engines which require 1000CCA or should I split the battery banks having one a traditional lead acid for starting each motor and the LiFePO4 bank dedicated for the inverter. My next challenge will be modifying the charge parameters of the outback inverter/charger.
I know a lot of these bms have Bluetooth, I’m thinking wifi connection for remote monitoring and data logging is highly desirable. Are there other bms with wifi connection or a Bluetooth - wifi bridge to log the data??
Didn't specify a torque spec. I am using a lock washer instead of the serrated flange nuts. I just get it down to snug and give it another 8th turn. Usually enough to hold.
How many of those bats would be needed to run an RV 15,000 btu AC? So one said I’d need 7 or 8 400 watt panels on the roof.I think I can mount 7 on my roof but not 8.
I do not understand how the BMS can balance the batteries separately with the charging power coming solely from the negative and positive in the end and beginning of series. Does the BMS balance the batteries through the thin "sensor" wires? I am using 1500AH 48v lead acid battery for my home UPS system. Those are simple, discharge only 30kwh max, charge them up with the inverter with only bulk and float/equalization. And they will basically be equal. Charging from both parallel ends of the 6 packs of 4 12v batteries. Edit: my lead acids are brand new and i expect them to last atleast 3 - 5 years of 40% DOD before throwing them away, but that's not hindering me from learning all i can about lithium and BMS (BMS which i understand nothing about). Edit again sorry: If i would want to build similiar packs like the one you built here, but make them in series to 48volts and build 6 suchs packs, Do each pack need a separate BMS? do each pack get a separate positive and negative from the inverter? or how does it work when you work with lithium in seris and parallel?
Very well.i have one question :i have 4 cells of this kind batery :12v/320A .the BMS must be 320A or less?i do not understand.can i use bms 150A?thank you
Could all the tape cause the batteries (cells) to not dissipate heat well enough? This was very enjoyable to watch and makes me want to make one (or more).
Perhaps. But so would an enclosure. For off-grid power, the c rate is very low so batteries don't heat up that much. It would actually be a benefit in cold temps. Like I said, there are lots of ways to build a battery. this is just a good and fast way to build one in about 10 minutes for a TH-cam video.
Balance leads can be cut to length individually as necessary. There is no point in having them same length. While voltage reading, there is no current flowing so there is no measurable voltage drop.
Hi: Thanks for this video. Can this cell pack and BMS times 3 power my golf cart, or is there to much inrush current for this BMS. No doubt the batteries can do the job, but how about the BMS.? Thanks. Bob
I'd like to build a 36 volt for my EZGO golf cart. How many cells would I need to equal six 6 volt Trojan T-105's ? And, can it be done ? Great videos, enjoy watching......
i gone a do 2 pack of 8s in series to make 2 pack of 24v and 320ah and them connect in the 2 pack in paralel and made 24v 640ah the question is to do that whith one bms whith 16s cell. the question is can di that 2 pack of 24v in series to them connect in paralel to make 24v 640ah which one 16s bms or not
Prismatic LiFePO4 cell prices have once again come down. Even with the wide-spread popularity of cheaper-than-ever, commercially-build lithium packs, you can still build your own for a lot less. I mean like 35% less and with all of the high-end features such as low-temperature cutoff and Bluetooth app connectivity. In this video, I will show you how I built a 280A pack for less than $700 and where I sourced all of the parts.
Buy 280Ah LiFePO4 Cells from Shenzhen Qishou Tech
www.alibaba.com/product-detail/Grade-a-lifepo4-3-2v-280ah_1600551390417.html?spm=a2747.manage.0.0.73e871d2RVwOMi
Buy RadioB Tech 120A BMS:
amzn.to/39OYgYA
My Preferred LiFePO4-Compatible Smart Charger:
amzn.to/3A2eeJq
I am a very novice LiFeP04 guy looking for the best, most cost effective solution for my needs...This video was excellent...How many cells can you actually add to that BMS and it still work? I have a truck bed camper and want to max out the AH for the space I have available. So can you build a 400 AH battery this way, using the same parts, just more cells? and do you have any other forums you are a host/member of that i might be able to sign up for?
Johnny, I offer coaching sessions here
freelyroaming.com/coaching
This guy is awesome, thank you so much for sharing. I used to buy a lot of ADCBATT 100ah lifepo4 batteries and although they are not expensive and still work, I plan to make one myself.
I thought that the cells from Ali express were b grade junk? I’ve heard several people never even got their batteries. Now, these were complete batteries, not cells, so maybe it’s different?
@@robertboyer5498 AliExpress is a platform with thousands of independent sellers. So the quality varies from each one. You can not blanketly assume anything across all of them.
Thanks for taking the trouble to share this. I dropped over 1500 UK pounds on drop-in batteries for my last boat, and on my current project decided to take the smart way and build my own pack. Just yesterday I got my box of Eve 280 cells and a good BMS, and am just getting started putting it all together. I had already got it pretty much all figured out, but it was great to run through it all again, and especially to pick up hints like the plastic between the cells and the issue of heating from the BMS. Well presented band clear. Top stuff.
lol 2 years later i just bought a 12v lifepo4 100ah battery for only 140 dollars after shipping and taxes so im glad i waited
Nicely done, straight forward, simple to follow by design. Thanks for sharing the education. I’ve got 16 cells 100ah that need a Bms to construct either a 12, 24, or 48v battery. This has been very helpful in understanding what needs be done to continue. 👍🏼
I have been using similar batteries to these as almost my only source of power for nearly 4 years now, all done from youtube videos like this and zero experience. The price to performance has improved so quickly in that time, roughly 40% more capacity for the same size and weight for less money is incredible.
people should not be afraid to try this, I really appreciate those who will encourage diy crafting. Some of the direct replacement options are total crap and unless you are willing to cut them open and see what is inside you have no idea what you have bought.
If you are not afraid you should try. If you are, you should not. I've seen too many poorly constructed electrical project built into moving vehicle and enough fiery inferno as a result to think everyone should do it. There are more than enough budget yet high quality batteries out there. Just buy a name you recognize and you will be fine.
Best thing I ever did! Going to build out a second one this fall I think so I can run my AC on an inverter.
These batts will probably be lower in price over time. The other facet not mentioned in this video is the ability to add more cells either in series or parallel. Either changing the bms or adding another depends on how you wire. But these are a great starter with budget in mind which can be increased over time without tossing any you've already purchased. 16 in series give you a 48 nominal volt setup which requires smaller wiring for the same watts used. The versatility is just wonderful.
bought 2000wh ac200p for $650. cant beat that on DIY.
This is a fantastic video! Thank you for making this. Gives me the confidence to try it.
i bought 4 cells back in i wanna say 2020.. and just got that same exact bms recently. works well. very nice build dude!
Thanks man. Love this BMS!
Thanks for the concise video...
One comment: The cell sense wires of the bms CAN be cut, there is no way 20ga wire, at .01 ohms per foot at 3,2 volts, with virtually zero current draw, is going to have any voltage drop. I notice nearly all the DIY builders think the same way, which tells me they all watch each others channels. The instrument doesn't have close to the resolution to read any difference. Simple ohms law for voltage drop. It would be microvolts
Of course it can be cut practically speaking. But when you make a video showing people how to do things, you need to teach best practices. The best practice is to not shorten them. There might not be a measurable difference but there is a difference at least in microvolts.
Hi Dan, BTW The 280K is the 6,000 cycle battery from EVE as the 280 normal is 3 - 4,000 cycles. Best charging the batteries in parallel to connect the positive at one end and the negative at the other end of the battery bank. This will avoid the first cell in the line taking the most current and last one the least.
If you get a chance to try the JK BMS it is the best on the market according to me and Off-Grid Garage on TH-cam. André
What do you like about JK BMS? Active balancing? And you actually believe what Andy says over there from his broken shack down under?!?!
Just kidding 😂 He's making some good content over there.
@@freelyroaming Yes the active balancing is the main difference. It is fully featured and seams to be very reliable. I was commited to package deal with a DeliGreencs BMS new parallel version so I could not change. André
Simple video, easy to understand. Glad you suggested to beginners to watch other more detailed assembly and test steps.
There are a few things you should take care of, apart from not assembling the battery on a steel table. Don't use an adjustable wrench to tighten the nuts - it.s too easy to accidentally creating a short circuit. Use a socket wrench instead. Don't use scissors to cut tie-raps but use short snips (with insulated handles) for the same reason. Do not tie-rap all balancing wires together, if there is any damage on the insulation of the wires you may get fire or at least smoke. Do not tie-rap the C- and B- wires in one bundle - if they short circuit you are disabling the complete BMS.
Never ever use those large heavy cells wrapped in just packing tape. It's too easy to get a puncture in the wrapping or denting the cells. Also, follow the manufacturers specifications on how to mount these cells. I've seen manufacturers specifying that you must compress these cells to make sure they cannot bulge, resulting in de-lamination of the cell.
How do you think these are EVE cells? EVE is a brand with a well known reputation so anyone selling EVE cells will leave the EVE label on the battery or at least have their own label with "Manufactured by EVE" on it.
You should watch some more of my videos before making your critiques. I've got plenty of real world and technical experience building off grid electrical systems. 'Not my first rodeo' is the common expression .There is plenty of other videos showing how I've built packs that I actually use. As I stated pretty clearly in the video, this was not meant to be a 'best practices' build video. It is just to show how components go together which was something requested by subscribers. And for a non-mobile setup, there is zero risk of insulation rubbing, chafing and shorting. As a full time traveler who does a lot of DIY projects, we don't have the luxury of a workshop full of tools. Learning to do with what you have is a very useful skill. It is all about understanding and assessing the risks and make it work with what you have. I assume you just landed here from TH-cam recommendations without knowing other already posted contents my channel. There is one all about cell compression as it sounds like you might learn a few things from it.
Excellent video! Exactly what I was looking for. Thanks for taking the time to make it.
WOW, nice and simple build one of the best to be honest and straight to the point, and yes LifePo4 batteries are the best I am glad you went with the Eve brand as I have heard a lot of good positive feedback from other folks too, thanks for sharing man, cheers.
this was fascinating but i disagree about one thing, i would definitely put the BMS on top. Put it on the side and it's vulnerable to squishing or impacts, but on the top it's protected somewhat by the + and - terminals. And i would cut the sensor leads (and the ground leads) as necessary. Because the input impedance of those sensor inputs is quite high. That means that those leads are not pulling any real current and so cannot drop a measurable amount of voltage no matter how long they are. I noticed that in the menu settings the balance precision was set to 30mV. The voltage drop on those leads is much less than 1mV. Great work though, thanx for posting.
Thanks. There are lots of pros and cons to how to build a simple pack. Doing what makes sense to you is what is important. This is just meant to show the easiest, no frills build so that more people can understand how they come together. Thanks for watching.
Great tutorial, can’t be more explicit. You got me. Cheers
i just bought a 304ah with heating for 1700 euro, it just has a JBD bms and eve cells - i know this costs only about 5-600 euro so its was hard to swallow, but it helps a local guy out and i dont have to think about it, i think next time in 10 years or so I will build my own.
If all goes normal world, a battery will be already built for 10c a watt
I am going to get this ordered up so that I can build out my own battery system for our camper.
That's exactly what I use it for. It has been great so far.
@@freelyroaming Outstanding!!!
thank you very much for this it has helped a great deal and very concise ,direct,well explained , and easy to follow .
You're welcome! Thanks for your comment and thanks for watching the video.
Thanks for the tutorial. Was debating whether or not to get off the shelf stuff. But this seems pretty straight forward and has more potential.
nice pun!
Nice video. One item that you should consider doing is to connect the main negative load leads directly to the battery terminal, then attach the balance lead on top of the load leads. That way the load leads have better contact with the battery terminal and the lug for the balance lead is not carrying load current.
But then it is not turning off if the voltage goes too low which is one of the main functions of the BMS. I would suggest not to do that.
He's talking about the stacking order of the ring terminals on the lug. It's not really that critical for off grid power use but for high current draw applications like EVs it might help. But even then it's not really gonna make any noticeable difference. Just best practices kinda thing.
@@freelyroaming Ok that makes sense. I understood that he didn't want the load to through the BMS. Sorry.
Thank you, very impressive! I'm picking up off-grid trailer soon and this build will be the perfect addition!
Very good! Iuse strapping tape with glasfibers in it. In case of the cells getting hot, it wont fall apart.
That's why I used. Although it's really not likely to reach any temperature hot enough to cause the adhesive to fail when this is used in an low c rate environment.
Nice job! Thanks for making this video.
Been waiting for a video like this for a long time. Awesome job on the video!
Thanks. Sorry it took so long!
Life is easy with those big cells
Excellent. I like your posts.
Congratulations my friend the best battery for lifepo4, it's a big Peck.
Thanks for sharing the knowledge. As right now, you can buy Chins 300AH around $970. I don't see much of the saving because the cost of 4 cells 3.2v is $750 + $130 BMS + bluetooth.
If not a lot of savings you will have more features like low temp protection, Bluetooth connectivity, smaller footprint and most of all, ease of maintenance. This for me was less than 700 bucks all in. I don't know about you but that's more than 300 bucks cheaper than Chins using my math especially when factoring in tax.
@@freelyroaming Espcially if youre going 48/51 Volts, savings add up.
Stay gold.
Thanks , very educational for beginners. Very good video compared to others out there. You stressed safety which is very important but safety glasses and at least sunglasses should be worn at all time working on battery like you did. No metal when welding or electrical work period.
Hi, since Im taking a deep dive into renewable energy, I understand there is a cost saving in a DIY version of a battery vs buying a LiFePo4 battery. My question is the following, how big or small is the safety concern of a daily use of a system built DIY vs just buy a portable solar generator system with a battery bank integrated in the same compartment like the Bluetties and Jacakrys? I do like to tinker with stuff, and you made it look fairly easy to build that 280AH battery. That motivated me to think in building a system.
Experiencing pain, seeing a bright yellowish-white flash of light and smelling my burned skin helps remind me to wear gloves from now on. 13V is enough to travel through a slightly sweaty skin surface. God saved me again. Aloe Vera gel is the best of God's creation to cure burns.
Seriously? You can literally grab both terminals with your bare hands and nothing will happen.
nice point on the length of the wires thanks!
I’m very confused on how many AH are in each individual cell. Does each cell contain 280 Ah or is it the set of 4 that make 280Ah?
You always have to specify Ah along with the nominal voltage. Each cell is 3.2V at 280Ah which makes 896 Wh (3.2x280). When you connect 4 of these cells in series you will increase the voltage but the Ah rating stays the same. So the full pack will be 12.8V at 280Ah which makes 3584 Wh.
Watt hour is a much better way to describe battery capacity because it can be stated alone without any other specifications.
I started with these exact batteries, built a pack of 16 in series @ 48v, I'm now building my 4th pack with a combined 57,344wh pushing 2 6500k inverters, and everything works great.
Thank you, I liked your video.
Thanks for watching!
Nice vid !
I just cant handle the strees of ordering on alibaba
2 years later, We now have the Eco-Worthy 12.8 V with built in BMS for $480. Down to .133 cents per watt hour.
@@deanelliott169 that's a good deal. Where are you seeing that? Their normal price for a 280ah pack is still $899
Thanks for the tutorial and recommendations. Good to know.
Just found this video and this channel.
GREAT JOB, thank you !!!!
Liked and subbed
Thanks!
Great information will help me greatly deal I'm goin to make battery pack to charge on off peak electric @ night to use during day giving me 24hr off peak lectricity shud save a great deal with big rise in energy prices, think l need to aim for sbout 10kw to run bungalow in day! Don't think l should have any problem putting that together, I'm a retired electronics tech! Just hope l can get all stuff you got shipped here to U.K. very good presentation lot good information thanks so much saves me time on researching all this myself!🤗🤩😎🌹
If you don't want large Ah , lead asic is still good enough for you compare to cost and lifespans of it.
Ok but now the real question is how do I build the individual cells from raw materials?
Thank you, I am now convinced that I am going to do this, very much appreciated 👍👍👍
I have a sailboat, the battery box will barely fit a group 31 batteries and at most I would be able to fit 2x 100ah batteries, so 200ah would be my limit. However, looking over measurements, I can fit 8x 280ah cells giving me 560ah. It doesn’t take much convincing that I don’t really need a case or a battery that looks like a battery because that’s more “acceptable” to most people. I’ve watched tear down videos and it’s nothing but foam and air, so it’s useless to me, I want the ah rather than the looks.
Cut the wires, the BMS has next to no current when measuring so therefore no voltage droop. Also when top balancing no need to wait when first connected but when charging leave at 3.65 for a few hours.
I've explained this in several comments exactly like yours. You'd understand if you are someone who makes videos like these
i got an aliexpress 150Amp clone of that bms and a BT module for i think under $80 USD shipped, if not around $75, that was a year or two ago
Correct me if I'm wrong but last time I checked, red was positive and black was negative. You appeared to have connected the blue bms negative leads to the positive terminal on the battery pack. Just an observation
I live in Canada. Any chance you could recommend a BMS with same features but also able to accommodate heat pads. Appreciate the tiem and effort you put into your videos.
Lyndsay,Whats you battery details ,Maybe i can offer help
@@GoGadgetsLife SOK 100Ah 12V LiFePO4. I bought them 3-months before the same battery with the option of heater pads became available.
@@lyndsaybeck2249 use an active balancer (aB) for your 100Ah cells. They have much more precisious performance then such types. You configure only the cutoff voltages (2,5Vmin / 3,65Vmax per cell) in your inverter.
The balancer manage the cells until 0,001V difference. An aB produce no heat and your system has no powerl loss!
negative: aB have no BT and Apps if you want present your cells your neighbour ....
Why not insulate behind the bms? maybe install it on a wood half inch block? or even some sort of a heat synk
There are a lot of things you can do. See my other build videos for those. This is meant to be the easiest way to put a pack together.
Great info.Thanks
Great video thank you. For your BMS and heat issue, why not place a thick sheet piece of silicone from a cheap silicone pot holder. Also did you have to pay $110 shipping per battery?
Very nice 👍
Helped me allot
Hi Dan, you spoke about balancing on the video at about 13m 53secs did you do a video on this after thanks in advance.
Nice work! Why was BMS chosen for a maximum current of 120A? It's only 1.44 kW. Is this power enough? Your battery can give much more, at least 2 times. For example, 200A (power = 2.56 kW) or even 250 A (power = 3.2kW). What is the basis for choosing a BMS with a maximum current of 120A? Thanks for the answer!
Cost and application often determine BMS selection.
200ah 12v lifep04 from redodo are 459. shipped and i even got a 30.00 amazon coupon so it was 429.00 kinda hard to beat, i am running a pair of them in series with my 3kw powmr all in one inverter for my camper.
200Ah Redodo doesn't have low temp cut off. For $469 you could have gotten a Golden Mate 200Ah that does like this diy kit. Running 2 of them takes up 3 times the space for someone with a smaller camper.
@@freelyroaming I had already watched a review on the redodo 200ah .. and understood that it had only a high temp cutoff. i am running a 18w warmer with auto thermostat it will cut on at 50'f and cutoff at 70'f (made for a chicken coop) since i am setting up inside a externally accessible storage area .. it looks to be the ideal answer to keep the batteries warm.
I’m going thru the Freely Roaming Series. A though came up. Where are the Bodwells. Do they have a TH-cam Chanel.
No they don't do TH-cam. We actually just spent a day with them last week. they have been living in Colorado while their son goes to high school. He was out here on California visiting college campuses.
Hello, I've seen a few of your awesome videos and am now hoping to get some advice.
I'm new to the battery / car camping scene. I plan to keep an Amazon LiFePO4 battery (maybe 2) in my car as a power source for a Dometic fridge, lights, laptop, etc. so I can live in my car on the weekends. I'm still shopping / researching so I wonder if Group Type matters, mixing battery / inverter brands or things like that matter?
I want to charge the batteries at work then bring it to my car and shelf in the cabin with me.
So far it sounds like I'd need the battery, and an inverter. And I think I can just plug a power strip into the inverter?
Do you see any issues or have any advice for this type of use?
I'd like to build a 36 Volt package for a ezgo golf cart.
How does the battery charge on negative? You leave the negative bms wires "hanging?". Huh, interesting. I would have thought you would be connecting loads directly to the battery but i guess if the bms has protections it hzs have to have the current go through it
That's correct. If you connect directly to battery negative, it would work of course but you would lose all of the protections of the BMS. Because this is a common port BMS, it means it charges and discharges from the same negative port. The protection schemes apply to both charging and discharging so you never want to connect anything directly to the raw negative battery post besides the BMS.
@@freelyroaming That makes sense now. Thanks a lot for making this video! It looks pretty straightforward to build this. That's a huge battery ! 4Kw of energy for only $700ish, wow
Actually the wires are on the positive of each cell on all the batteries I've seen or worked on.
Well actually...... 🤦♂️ I've already addressed this in other comments. The wires can be placed anywhere on the bus bar that connects the positive of one cell to the negative of the other cell. You get the exact same reading.
What about using coroplast corrugated plastic signs as your dividers for battery and bms that way they can get some air between them
The only problem is if you use something too thick the bus bars will probably not reach the studs.
It's more dangerous to get into a car and drive down town, but I've never had a disclaimer about that. Lol
First time for everything
I am using a couple of those JBD bms's from radio tech. They haven't givin me one issue in yrs but the app can be frustrating
That's good to hear. The app is very powerful but not intuitive. I'm testing to make sure the data is accurate and reliable and the will take time
Thanks Great Video Why was cell #1 red and a B flashing in the bluetooth display?
It is showing the balancing of the cells. Red signifies which cell has the highest voltage and is being resistively drained to a lower level.
So the 3 black wires will go to trolling motor ground and than run trolling motor red wire to battery?
thanks bro!!
Nice video, Im thinking about building one myself and took contact with the reseller you linked, so did you have any problem with them and Cassie Wang there said it would cost 560$ with shipping and all to Europe. So you think that this is a good price or should I wait?
I'd like to build a 36 volt 100 amp hour battery for my 36 volt ezgo golf cart. Any suggestions on components would be appreciated. Thank you, great videos !
I did this set up with just the 120 amp bms. I have a 40 amp. Rich charge controller and two 200 watt. Panels. Also 3000 watt pure sine inverter. I have been all over the app and can't get my cells to charge past 13.4. I put my Noco genius 10 on it with the bms hooked up and I only get 13.4 and only 3 out of 4 red bars on the charger no matter how long I wait. When I charge the cells without the bms hooked up, I get 14.4. Then, as soon as I hook the bms up it takes it down to 13.4. I have calculated about 50% capacity. Maybe less. The only thing I can think of is the bms needs to be a 250amp? Advice would be perfect. Maybe parameters I need to change? Thanks
Can you do a video on the Bluetooth connection. I am concern there are complication or it gets tricky to connect to it.
I've ordered cells from Shenzhen Qishou (QSO) manufacture but I have concerns. Now that iIve found your video, how do these QSO cells perform, two years on? Are they worthy?
32V battery build. On my boat I have 2 banks of 4 8V lead acid batteries that I would like to replace with IiFePO4. Each battery banks is independent for port and Starboard motors. Currently I also have the 32V inverter connected to one of these banks. Having searched the internet I quickly realized this will be a custom battery made from cells like in the video. I can find 32V 10S LiFePO4 BMS units. The difficulty I'm having is can I use the same battery bank I make to start the engines which require 1000CCA or should I split the battery banks having one a traditional lead acid for starting each motor and the LiFePO4 bank dedicated for the inverter. My next challenge will be modifying the charge parameters of the outback inverter/charger.
Yes akb LiFePo4 🔋⚡👍
I know a lot of these bms have Bluetooth, I’m thinking wifi connection for remote monitoring and data logging is highly desirable.
Are there other bms with wifi connection or a Bluetooth - wifi bridge to log the data??
What torque did you use on the terminal nuts? Perhaps I just missed it.
Didn't specify a torque spec. I am using a lock washer instead of the serrated flange nuts. I just get it down to snug and give it another 8th turn. Usually enough to hold.
Do you have another BMS you recommend? The one you mentioned is no longer available on amazon.
This is their latest option
amzn.to/3RZef9B
@@freelyroaming Thank you!
Nice👍👍
10 to $15 for a aluminum heat sink is well worth the investment to protect your battery, just my opinion of course
What would the heat sink be for in this case?
How many of those bats would be needed to run an RV 15,000 btu AC? So one said I’d need 7 or 8 400 watt panels on the roof.I think I can mount 7 on my roof but not 8.
Very informative video. You mentioned at the begin about showing a 3rd temp sensor, was it mentioned or did I miss it?
I do not understand how the BMS can balance the batteries separately with the charging power coming solely from the negative and positive in the end and beginning of series. Does the BMS balance the batteries through the thin "sensor" wires?
I am using 1500AH 48v lead acid battery for my home UPS system. Those are simple, discharge only 30kwh max, charge them up with the inverter with only bulk and float/equalization. And they will basically be equal. Charging from both parallel ends of the 6 packs of 4 12v batteries.
Edit: my lead acids are brand new and i expect them to last atleast 3 - 5 years of 40% DOD before throwing them away, but that's not hindering me from learning all i can about lithium and BMS (BMS which i understand nothing about).
Edit again sorry: If i would want to build similiar packs like the one you built here, but make them in series to 48volts and build 6 suchs packs, Do each pack need a separate BMS? do each pack get a separate positive and negative from the inverter? or how does it work when you work with lithium in seris and parallel?
Very well.i have one question :i have 4 cells of this kind batery :12v/320A .the BMS must be 320A or less?i do not understand.can i use bms 150A?thank you
Pressure from tape will damage edges of first and last cell
Could all the tape cause the batteries (cells) to not dissipate heat well enough? This was very enjoyable to watch and makes me want to make one (or more).
Perhaps. But so would an enclosure. For off-grid power, the c rate is very low so batteries don't heat up that much. It would actually be a benefit in cold temps. Like I said, there are lots of ways to build a battery. this is just a good and fast way to build one in about 10 minutes for a TH-cam video.
so in order to buy from alibaba there are stipulations are there not?
Since you're connecting 4S in series, why does it come out 12V and not 48V?
Each cell is 3.2v.
Balance leads can be cut to length individually as necessary. There is no point in having them same length. While voltage reading, there is no current flowing so there is no measurable voltage drop.
While it's true it is not measurable, it is not true that there isn't a voltage drop.
Hi: Thanks for this video. Can this cell pack and BMS times 3 power my golf cart, or is there to much inrush current for this BMS. No doubt the batteries can do the job, but how about the BMS.? Thanks. Bob
I'd like to build a 36 volt for my EZGO golf cart. How many cells would I need to equal six 6 volt Trojan T-105's ? And, can it be done ? Great videos, enjoy watching......
3.27 volts on the tester per cell
@freelyroaming did you have any problem with the cellar supplier?
i gone a do 2 pack of 8s in series to make 2 pack of 24v and 320ah and them connect in the 2 pack in paralel and made 24v 640ah the question is to do that whith one bms whith 16s cell. the question is can di that 2 pack of 24v in series to them connect in paralel to make 24v 640ah which one 16s bms or not
Does this bus do active or passive balancing?
Can i solar trickle charge a LI battery,the type used on a power tool.
Have you tested cold temp disconnect is working on this bms?
Why not top balance before assembling?
I don't know if it was ask can you use these for car audio