16S LiFePO4 Active Balancer Problems (Not Beginner Friendly)

[@WillProwse]

Just purchased two 8S balancers to see if that fixes it. User "fox fried" made a good point. If one bms disconnected, you would have a disconnect halfway in the pack. Which could cause the voltage to rise. Makes total sense considering what part of the board fried. Part two coming soon ~~~~~~~~~~~~~~~~~~~~~~~~~ Does off-grid solar confuse you? Check out my DIY friendly website for solar system packages and product recommendations, and so much more! www.mobile-solarpower.com Join our DIY solar community! #1 largest solar forum on the internet for beginners and professionals alike: www.diysolarforum.com Check out my best-selling, beginner-friendly 12V off-grid solar book (affiliate link): amzn.to/2Aj4dX4 If DIY is not for you, but you love solar and need an offgrid system, check out Tesla Solar. Low prices and great warranty, and they can take your entire house offgrid with their new Powerwalls: ts.la/william57509 ~~~~~~~~~~~~~~~~~~~~~~~~~ My solar equipment recommendations (Constantly updated! Check here first): 12V/48V Lithium Batteries: www.mobile-solarpower.com/solar-batteries.html Solar System Component Directory: www.mobile-solarpower.com/solarcomponents.html Plug-N-Play Systems: www.mobile-solarpower.com/full-size-systems.html Complete 48V System Kits: www.mobile-solarpower.com/complete-48v-solar-kits.html DIY Friendly Air Conditioner/ Heat Pumps: www.mobile-solarpower.com/solar-friendly-air-conditioners.html Complete 48V System Blueprint: www.mobile-solarpower.com/48v-complete-system-blueprint.html ~~~~~~~~~~~~~~~~~~~~~~~~~~ My Favorite Online Stores for DIY Solar and Coupon Codes: -Current Connected: SOK, Victron and High Quality Components. Best prices and warranty around: currentconnected.com/?ref=wp -Signature Solar: Cheap Server Rack Batteries and Large Solar Panels: www.signaturesolar.com/?ref=h-cvbzfahsek -Ecoflow Delta Official Site: My favorite plug-n-play solar generator: us.ecoflow.com/?aff=7 -AmpereTime: Cheapest 12V batteries around: amperetime.com/products/ampere-time-12v-100ah-lithium-lifepo4-battery?ref=h-cvbzfahsek -Rich Solar: Mega site and cheaper prices than renogy! Check them out: richsolar.com/?ref=h-cvbzfahsek -Shop Solar Kits: Huge site with every solar kit you can imagine! Check it out: shopsolarkits.com/?ref=will-p -Battery Hookup: Cheap cell deals bit.ly/2mIxSqt 10% off code: diysolar -Watts 24/7: Best deals on all-in-one solar power systems, with customer support and distribution here in the USA: watts247.com/?wpam_id=3 ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Contact Information: I am NOT available for personal solar system consult! If you wish to contact me, this is my direct email: [e-mail] Join the forum at diysolarforum.com/ if you wish to hang out with myself and others and talk about solar FTC Disclosure Statement and Disclaimers: Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :) DIY Solar Power with Will Prowse is a participant in the Amazon Services LLC Associates Program, An affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com

[@SiriusSolar]

Is there no data logging so you can't go back and see what was happening during the balance?

[@WillProwse]

No, there is not. That BMS shows error codes but does not log them. I've had trouble connecting to the one I need right now too. I hate the app it comes with. It should have logging

[@WillProwse]

@@FullSendPrecision cells need to be in series the whole time for it to work. If there is a break, one of the balancing circuits could raise to a very high voltage. It needs to be connected entire time. Which I didn't think about before

[@AlabamaConstitutionalCrusader]

Any idea what could cause my 800 watts of panels to not completely charge my 200ah Lifepo4 batteries in 5 hours of full sun ? Its been a headache

[@SiriusSolar]

@@AlabamaConstitutionalCrusader how many kilowatt hours is your battery bank?

[@kuhrd]

I have 2 of these active balancers on 2 separate 48v systems running for months without issue. Your pinned comment is very likely correct that having the pack split between 2X 8S BMSs caused the issue. Also, these balancers have a solder blob across the pads for a switch. I have this set up in each of my systems with a voltage control board so that it doesn't enable the active balancer until the total battery voltage goes over 54v. This helps keep the whole system top balanced at a much faster rate than you would get with a regular BMS so you don't get the short cycling on and off if it has been a few weeks since the batteries have been fully charged up and it doesn't try and balance at the bottom end of the discharge curve. If I had new batteries I likely wouldn't need the active balancer but it is still a whole lot faster at fixing any cell drift if I have a nice sunny day after 2 or more weeks of cloudy/overcast days where the batteries didn't have a chance to get a full charge.

[@JoeMudrich]

I'm using a very similar active balancer (with screw terminals) on my pack with used 180Ah cells for several month now. The balancer actually made the pack usefull since my BMS never managed to balance the Pack. It's perfectly balanced now.

[@xdagasx4153]

do you use bms and active balancer together,I am thinking to go this way,cos bms do not have that much power to balance

[@JoeMudrich]

@@xdagasx4153 yes. BMS and balancer are connected in parallel.

[@mrj2848]

Same exact thing happened to me with the same 16s lifepo4 pack and the capacitor type balancer. The wires to the balancer got really hot and the balance board too. Immediately disconnected for fear of fire hazard. 5 years later I built a 4s car battery and used the same type balancer via 5A fuses and it works beautifully. Balances down to 12mV. Maybe we both got a bogus 16s version. Keep of the great work Sir.

[@4kfishing223]

i have been using an active 8s balancer for more than a year now without disconnecting it once and dit works really good

[@marinetrax]

You still running an active ballancer without disconnecting it? 3 years on?

[@hbseth1867]

Damn Will, I JUST had received mine and did a search to see if I was missing anything before wiring it up short of the 16s capability. Of course I chose your video first lol. 36v 105ah pack here using the same balancer. I loved that I could use it with my current 12s and then keep it for when I upgrade my golf cart to 48v/16s. After watching you, I was reluctant to charge overnight with it so I actually rolled my cart outside and away from any fire hazards before starting the charge cycle... lol In the end, mine worked great and isn't even warm to the touch. I had one eye open all night tho!

[@xdagasx4153]

I use this same and some other active balancers,mostly 6-8s and it works so well,each cell voltage is spot on,so accurate,I am thinking to use bms+active balancer together

[@xdagasx4153]

and it is no any heat or even warm,always cold active balancer

[@BradCagle]

I use the Heltec brand of these (looks the same but yours is missing the heltec silk screen) but mine work like a charm man!

[@nateb3105]

Yep 100% the same, been using the 8S for a month now & its been really useful to keep my packs well balanced (A- grade)

[@jackoneil3933]

Excellent test and information Will. It also confirms what I've observed with active cell balancing compensating for variations in individual cell chemistry during cycling and ended up severely unbalancing the pack. When removed the active balancing, and let the BMS manage the charge in two deep charge cycles the pack balanced nearly perfectly.

[@neliosamch3195]

I have two active balancer in each pack working flawlessly, however, at the beginning I notices in the app that cells voltages were fluctuating and acting erratically. l have to check each wire with the ohmmeter and found that some ring terminals were crimpled incorrectly over the wire insulation making faulty connections. After the faulty terminal were replaced with proper connection everything started working without any more problems.

[@WillProwse]

Oh good point. That could totally happen.

[@agustinrogberg6124]

@@WillProwse why you didn't check voltage in the connector to make sure everything is properly connected? In my case after a couple of cycles one buss bar was loose, did you check that?

[@sjdtmv]

Cant beat soldered joints over crimped one

[@neondawnfpsgaming]

@@sjdtmv I build 18650 packs and mod electronics, and i have to agree with you on that. any time i make a crimp i have to add solder to make a true mechanical and electrical connection. best to side on caution.

[@Garyguygax]

@@sjdtmv Except for mobile applications where vibrations break the solder connections.

[@RJ-cc1fz]

Solar engineering did a video on that balancer. The cell voltage difference needs to be extremely excessive for it to balance at anywhere close to 5 amps

[@solventtrapdotcom6676]

So, it only puts the pedal to the metal when there's a reason... Not sure why people say that like it's a bad thing.

[@marinetrax]

@@solventtrapdotcom6676 Thats what I dont understand. Why cant it just remain on 24/7 35?

[@FuyangLiu]

I think you should check the connections with voltage meter first before connecting it. I have a few of those in my own battery pack and they work greatly 🤷‍♂️

[@djrrmml7514]

Finally someone that is not looking at voltages!

[@CaptainProton1]

be warned, those capacitor active balancers can explode if the cell delta gets too much as they then chuck out very high amps. Mine exploded near 98% depth discharge on 18650 pack ...yep was bound to be a big difference of cell voltage. Nearly caused a fire. Best way to use them is when Lifepo4 battery is fully charged, then just use them to top balance around 3.55v to 3.65v for a relative short amount of time it takes to balance them up. Then disconnect...do not leave them on the pack as they will balance all the way to full discharge leaving you with a very uneven pack. They do work great but only above a certain voltage and for top balancing.

[@JimFisherDIYPortableSolarPower]

I agree. My experience has also clearly verified that simply connecting an active balancer, and leaving it constantly "on", only makes the cell imbalance worse when you are working with other than brand new, A grade cells. It becomes glaringly apparent as the cells approach the top of the charge curve. The Heltec active balancers are very good at what they do, but they must be manually switched on to be most effective, and only near the top of the charge curve. Then they must be manually turned off.

[@marinetrax]

Hi, so, is there someway that you can set up this type of system and not have to continually be manually checking them all the time, turning the ballancer on and off? Thanks

[@joechan9126]

The "Up in Smoke" section: now sponsored by active balancers

[@thonatim5321]

With Cheech Marin & Tommy Chong as the spokesmen.

[@dalehoffman4405]

A quick scan with your IR camera while the balancer and charger are running might give you some piece of mind. If your right about a voltage spike after one bms disconnected you probably wouldn't wouldn't have caught any thermal anomalies at the time, but at least you've checked your work before walking away from a battery that big.

[@kirovoleg]

I have the 4s version of that balancer. It worked fine for me. I had done a top balance of the 4s pack but a cell that started drifting and would peak before the others shutting down the bms. At first I kept the balancer 24/7 and it balanced great but after a couple of days I saw that it kept balancing on low SOC and managed to make another cell drift only on peaks. So I disconected it when it balanced at a high SOC ans cell voltage of 3.55 a week ago and lowered the boost voltage to 3.475. So far the pack is balanced with no more than 20mv difference at boost. I will use it for periodic maintenance of the pack without having to dissasemble it and top balance.

[@ecospider5]

I was thinking of putting heat shrink on the handles of my tools. Like the socket wrench. It should greatly reduce the chances of dead shorting a battery.

[@AintBigAintClever]

When wiring my lead-acid pack I wrapped the ratchet and socket in insulating tape right to the hilt as each 2 volt cell has its own bolt terminals, so there was plenty of scope for shorting stuff out. My LFPs arrived yesterday though so I've got to do it all again :)

[@ecospider5]

Good idea.

[@kaizercharles]

Active balancer does the job, unlike onboard bms balance so slow pretty much no balance at all. It just cant take the heat. Better to isolate the balancer next to the batteries with better air cooling. Looking forward for the next one.

[@MrSukhdeep3]

I have active balancer and working fine since two years almost

[@bentleyjarrard885]

The Bluetooth active balancers that come in a metal case seem to be fairly reliable. I've been using a 2A version for a couple of years, so far so good. The product I'm referring to is to one by JK BMS that is sold under various brand names on the usual sites with Chinese electronics. It has some nice features like an On/Off slider in the Bluetooth app, adjustable balance current, (0.2 to 2.0A) cell delta voltage trigger setting, internal cell resistance display. The one thing it lacks is the ability to set a low and/or high voltage threshold value so balancing ONLY occurs during the lower voltage part of discharging and the upper voltage part of a charge cycle. Cell balancing in the FLAT region of the voltage curve is not necessary and may even unbalance cells more. As mentioned in the video, If you have a set of cells that are not well matched like I do then the active balancer does help quite a bit. BTW, Off Grid Garage just did a couple of videos on the same balancer featured here. His did not "burn up". Perhaps you just got a bad one?

[@davidchristensen1219]

I have been using this balancer as well. I bought a second one that has a temp probe and RS-485 connectors. I've written my own application to monitor my solar equipment (Schneider) using ModBus and my plan is to integrate the JK BMS into that system so I can tell the CC to go to Absorb or Float if a cell reaches my defined limit. Or, since I have the application integrated into Home Assistant, I can control devices (like A.C.) to bring down the load or worst case, tell the Inverter to go into Standby. I don't like how most BMS' disconnect the battery from the equipment requiring a manual startup. I can do it programmatically w/o the need to use a resistor to get all of the caps charged up and thus saving my equipment.

[@bentleyjarrard885]

@@davidchristensen1219 Wanted to reply to you but its been a couple of crazy days. I'm wondering if you watched any of my videos? Sounds like you have the same Schneider 6848 Inverter. I would be interested in any info you are willing to share regarding the Schneider communications protocol. I have the Schneider ComBox but don't have their battery monitor so the State of Charge just shows N/A on the display. I was wondering if it would be possible to take the SOC value from the BMS CAN Bus, format it properly and send it to the Schneider at the correct ID or Address? Any suggestions? As far as the BMS disconnecting the battery from the system, that is a last resort issue to prevent permanent damage to the cells. If the BMS is set correctly to disconnect if any cell reaches 2.5V the Inverter should be set to 44V or 45V so it drops the load BEFORE the cells get to their critical lower limit. In any case, Unfortunately, my computer and programming skills are novice at best. I had to hire someone to set up the Websockets and HTML interface for the CAN to RPI to Network connection. I did learn a little HTML, CSS and Java Script so I could reformat the way the data is being displayed but it took me a while.

[@lithiumrv1017]

My 2 year experience, with the same. The BMW electric car battery back had a damaged cell that was only 20 amp hours when the pack was supposed to be 200Ah for the 16S pack. Two of these in parallel allow me to cycle the battery with 150Ah of capacity running a refrigerator. The current will exceed 5A with huge cell voltage difference, if cell gets to 2v for example. The system can only do high power in small bursts that use up to 15ah of power, before I trigger the cell difference cutoff, but it returns to stable quickly with 2 of the 5A balancers. Exclusively solar systems never have a chance to top off so active balance is sometimes necessary.

[@fjpavm]

From what I have gathered an active balancer on LiFePO4 batteries is only good for doing the top or bottom balancing on an already assembled battery. If you plug it in while the battery isn't very close to full or very close to empty it will just continuously try to balance based on voltages and possibly unbalance the battery even more. But they are good tools to have when the BMS is cutting out at the top or bottom because it's balancing current capacity is too small. That is the time to use the balancer to get a quicker top or bottom balance since the voltage differences are actually indicative of charging state differences.

[@Bobbel888]

At least you mentionned the Type of Batterie. Else you have a burned balancer board and nobody knows Why.

[@derBomber69]

So i wanna share my own experience with this things: Side Notes: 15S - Li/Ion - minV 3V - maxV 4V - Ah 460 used Tela Moduls First of all, i wouldnt sept at all, if not all cabels are fused with this size of pack. At first i only used a chinese progammable BMS, but at this time i also use the internal fuse ( thin wires) so the cables are propper fused. I also added 5x20 3A fuses for all balance cables that go to the BMS. Then i went with the Batrium BMS and it worked fine. But afer month i checked the voltages and they were at 50mV difference. I bought one of these balancers like you. Then my mind change to i played with the settings when the bms start the balancing process. My pack is full at 4V and you should never think --> the sooner the bms start with the balancing, the better is it. Now: I didnt use the active balancer at all, the voltages are within 20mV now and they sink I set it now to 3.85V to allow the ballancing So i would never use one of these balancers, because they are not programable. In my case the balancer would start the process way to early.

[@justdoityourself7134]

I have this same active balancer. Been running just fine for months. I used it in place of a top balance and worked like a charm. It is too bad it didn't work out for Will. But did he really want it to work?

[@georgesrisomsak9650]

@Sherylin this will definitely help, but he believes he found the failure was one bms disconnected, possibly spiking voltage to the balancer, and causing the failure on the one side. He will re-review this as he has two 8s units ordered, and we'll see if they pass his test. I've been following him for quite some time, have learned a tremendous amount from this channel, and trust when he says he doesn't like something. He's got a lot of experience with all the gadgets out there, he's saved me time and $ for sure already! I haven't removed the balancer yet, I'll definitely be keeping tabs on its temperature. It's been in 160+ degree heat within the vehicle sitting in the sun even! It's balanced to perfection, and it doing its job so far, only one weeks worth though.....

[@georgesrisomsak9650]

@Sherylin collaborating with ideas and testing is what gets it done! Take all of us! :) Thanks for your input!

[@AimeMOfficial]

hey i really need your help. i want to have a power source to run my sump pumps off of my solar panel price a d have some type of charger to charge the batter off grid power at night.

[@SuperVstech]

Any hybrid inverter, or inverter charger could manage that task pretty easy. Off the shelf.

[@AimeMOfficial]

@@SuperVstech thank you for your reply, any in perticular that i can use??

[@Kineth1]

Hey, I really need you to click the link in the description where he provides blueprints for DIY systems to do exactly what you're asking about.

[@georgesrisomsak9650]

Damn... I installed one of these on a 96ah headway bank, 4s12p @ 14.6v. it been good for the last week, but now I'm thinking to go back to the passive balancer. It has not let the smoke out yet, but now I'm stressing on it! I use the setup for car audio, so it see's an incredible amount of voltage fluxuation constantly when being pushed. I'm weirded out now! Going to check it this very moment.. Update - Cells are perfectly balanced, board is cool to the touch. After reading other comments, I'm pulling the bastard. Insurance won't cover a fire from one inside the car I'm sure. I thought I was "upgrading"... 🤣

[@cyborgxxl]

You can cast the balancer in synthetic resin. This dissipates the heat better and makes the balancer largely fire-proof. I've already done this on 4 of these balancers. ;-)

[@WillProwse]

That is smart

[@John-gm8ty]

Off-Grid Garage has dome some interesting videos on active balancers too.

[@deltoncbaker]

The off grid garage guy doesn’t like active balances either, but he says they great for getting a new pack up to speed. He also says once the battery pack is up to speed you should take it off the battery pack until the battery pack is way out of tolerance again. He has hours of data to support his findings.

[@WillProwse]

That's good advice. That's what I was planning to do. I would never leave one connected to a battery

[@bstrong4evr]

Seems like there are a lot of condescending critics making rude analogies. It seems to me that Will does more work in a day trying to help people than these critics do in a year.

[@FullSendPrecision]

I've been playing with the 4s version on my new 400ah 12v 4s pack. No problems thus far (I only let it run while I'm in the shop) - But it does seem to always be balancing... In an off grid situation I could see where it would drain the battery if you're not careful.

[@arebear4797]

This is absolutely true. i have seen few drain cases with small pack connected with this device. otherwise this is good device.

[@nateb3105]

Some (Heltec) have a sleep mode below 3.0v & 9ma current consumption. How small are these battery packs? how long before sun?

[@jeffdege4786]

Cruising sailboats with electric auxiliary engines routinely go weeks or months operating in a pSOC. Depending upon weather they can find it impossible to reach full charge off of solar. Drifting cell balance can be a real problem that has to be dealt with. How should we deal with it?

[@solventtrapdotcom6676]

Apparently, don't. Just blow out cells and catch on fire. It's totally cool. No problem.

[@Infinion]

I mean your options are to passive balance that uses large value resistors and slowly bleed charge to adjascent cells or to active balance faster like this one where it uses a "flying capacitor" circuit scheme to shuttle charge from the battery to the capacitor, back to the battery and it travels down the line, in bidirectional fashion. Ends up being much faster than the resistors but is it more efficient. But how quickly does drifting cell balance happen? IMO if you're not in a place where you can service the electronics then a simpler more robust and slower solution seems safer. Speed only seems necessary if the drifting cell balance exceeds what passive balancing can overcome.

[@odudex]

Did you connect the active balancer in parallel with another BMS? Couldn't that be the issue?

[@holgerkarst6511]

Had the same problem here two times. Same Inexplicable heating and the capacitors hot. Ladder track burned out. I switched to another type of balancer.

[@asificam1]

2 things, I would like to know if that balancer is 2 smaller balancers running half and half, or 2 smaller balancers with one cell being overlapped, or if its actually one single balancer... The latter options all work fine with this design, they're basically a series of capacitors (or banks of 3 by the looks of it) that have a MOSFET matrix that connects each capacitor in parallel with one of the battery cells, and then a second bank of MOSFETs that connect all the capacitors together in parallel. They're basically doing the same thing as if you manually rewired the pack so all cells were in parallel... only because they're capacitors that are rapidly switching between parallel and series, they are able to effectively place all the cells in parallel WHILE they're operating in series without any major issues... however this means that balance current is directly proportional to voltage difference between cells, and it also means that if a MOSFET or capacitor fails... bad things can happen. Looks like one of your MOSFETs either failed from something like thermal runaway or they somehow didn't disconnect properly when needed. There is a little oscillator that changes which set of MOSFETs are connected, if say one MOSFET didn't disconnect... well that would cause the board to burn.

[@loucinci3922]

Bummer. Please, share your views on top vs bottom balancing. Which is better? Thanks for sharing.

[@WillProwse]

Top balance always. I have old videos on this. I used to bottom balance years ago when I ran without a BMS. Not necessary anymore. Top balance only.

[@francespueo5367]

Over my head, but important for me to understand the complexity and danger.

[@phsouzabr]

You should test a Batrium fancy BMS 😁 You can see what it's doing on the computer screen, and it logs everything

[@captaincurt3180]

Will: Johnny on the Spot! I was up until 2:AM this morning wondering and researching about active balancers. I am still wondering, but this video goes a long way toward convincing me that active balancers are not worth their salt. 😫

[@jimthvac100]

You did not read his comment. Not balancers fault; he was using two BMS and during charging one disconnects can caused a voltage spike as half the back is disconnected. He is going to do it again using two balancers one paralling each BMS

[@captaincurt3180]

@@jimthvac100 Thank you Jim. You are correct, I didn't read what Will had written. It makes complete sense now. I'm looking forward to the next video!

[@dead6last]

i use a heltec 6s balancer on a yinlong lto bank 80 ah . after top balance i hooked it up works great. after 1 week still good....

[@projectnemesi5950]

I think there currently a problem with counterfeit brands. Heltec is a well known chinese manufacturer/brand, and I think people need to make sure they are not getting a counterfeit one. The counterfeit ones use counterfeit components, and those components could be completely off in their specification, leading to events like we see in the video.

[@ab_ab_c]

Hmm.. Odd. The Off Grid Garage guy in Australia seems to have some pretty good luck with his active balancers. Maybe try the brand that he's using... Just an idea.

[@jstaffordii]

Andy removed his active balancer and went back to top balanced with bms only. The cell deviation was too high with full time active balance.

[@ab_ab_c]

@@jstaffordii What a shame--BMS top balancing wastes energy...

[@CaptainProton1]

The NEEY active balancer works great though and has settings to only balance above a certain voltage

[@uac1710]

Active balancer becomes hot when balancing. I've glued my balancer to my bms as its heat sink. I've been using it for almost a year now. I'm using the 1.2A version.

[@mike.burdis]

Sorry to hear that man. Did you set the solder jumper correctly for your battery chemistry?

[@66bigbuds]

I didn't know you could use a bms and an active balancer together.

[@WillProwse]

You have to. You need bms to manage HVD and LVD.

[@Zorlig]

Yeah this is what I do

[@martehoudesheldt5885]

bms controls top and bottom and balancer tries to keep the cells equal.

[@robertcrosser5946]

I have 2 SOK 48v in parallel and 2 24v renogy in series do i need a battery balancer for my solar RV SETUP

[@Jojo-tl6io]

Will, can I use an AC to 18650 battery pack? I have 14S 26P 48V system.. thank you.

[@marcvictoreykens3140]

Same smoke here, that's why i search this info. Run a S8 200Ah lifepo4. Was pretty well top balanced after 1 cell was abit down. And Just wanted an extra balance function because bms do not. Looking out for something else now

[@victorreppeto7050]

Active balancing is a good idea. I have the 8s version and it really helps... I wish I had the money to throw away my entire pack and buy all new cells but I don't so that recommendation does not work for me. I think the air you breathe is a bit thinner than the rest of us mere mortals.

[@miikkakangas6750]

I’ve got small active balancers on two diy Nissan Leaf gen1 4S style batteries (one is 4S3P the other is 4S6P). These only seem to kick in when the cells are heavily discharged, but seem to work then.

[@pothofm]

So do you need to charge the batteries at the same time when doing a top balancing?

[@lesliegreen1688]

ok am using active balance however i do not use bms but my max volt is 54.6 however i realize if you increase te voltage the active balancer capacitors will hot & burn the first one burn & i replace it & it working good so check the voltage maybe too high

[@SATAOfficial123]

If I buy 10-14s, can under 10S also use this battery balancer?

[@stevegorkowski3246]

That balancer failed for me but I ordered two. The second worked but if you do high charge currents the board may not keep up and cells can over voltage. My testing was on lto 20s.

[@laurabarnes3295]

How will conect 3.7v 5000mah 48pic to get 12v 100ah

[@magicmanspaz]

Are you getting another to actually test?

[@gertvanwerven6355]

I have the exact same one but it's 17s. So the last red lead should not be used. Could that have been the problem?

[@browntigerus]

6.3v capacitors are not good in my book. We are always taught 2x the voltage. So needs to be 7v caps minimal.

[@EdisonWong2004]

If you look at a lifepo4 voltage curve, yes it can charge up to 3.5v, but it quickly settles down to its nominal voltage of 3.2v, and it stays there until the battery is drained. So technically 3.2v (2) = 6.4 v is probably fine.

[@Infinion]

​@@EdisonWong2004 yeah like Will said, it's probably not the fault of the capacitors, or at least the voltage rating. Something else is going on here. to generate the heat and destroy the fets.

[@IvanWheatman]

Just assembled a 280Ah lifepo4 pack with Overkill 16s Bms and the very same balancer yesterday. It lasted about 10 seconds, then one of the capacitors literally flew 2 meters away and the whole thing went smoking.

[@jamatiaborok1094]

My hardware active balancer when charging the battery pack when I touch the active balancer body it make a small electric shock me when I remove the che charging socket it don't shock me what are the problem is on here when the battery pack full charge it couldn't actively balance all the cell voltage are not same. What are the issue here please any help

[@Bigislandguy]

I tried 2 different 4s balancer.Seemed to work at first but not for long. Mines didn’t burn up it just stopped working. Or never worked. Idk

[@beauinator2]

have 8x 12v 100ah liion batts for a bank. (48v) can you recommend me a devent inexpensive bms to manage all? thank you

[@carlossousa3285]

I have one of those on a 48v 150ah system. when cell voltage goes above 3.38v, the positive and the negative cells connected to charger and can reach 3.8v while the others still at 3.4v or so. and yes, I have top balanced them to 3.65v in parallel. good luck!

[@egnegn123]

The balancer is no BMS and cannot prevent going cells above 3,60 V. You should always have a BMS in place to protect single cells from overvoltage.

[@carlossousa3285]

@@egnegn123 you're correct and I didn't say that. I said that the active balancer will not keep the cells from being all over the place while charging, once the charge stops, then it will bring them close to each other. I have a 48v 150ah bms from Daly and it does the exact thing. In my opinion to prevent what seems no balancer can do is to stop charging above 3.37v per cell as its seems above this voltage is when all hell breaks lose. hope to be making sense ;)

[@chapulino1000]

I burned an identical one, but identify the problem, the busbar nuts were loose and therefore there was bad contact between the cells. check the tightening torque of your nuts

[@asificam1]

Either the balancer was defective (using dodgey parts) or it ran at such an imbalance for so long that it overheated.Theses are simple versions of active balancing, quite dumb actually, they just connect caps to the cells and then disconnect from the cells and connect the caps in parallel (now all caps are balanced) then back to the caps across the cells which dumps power into low cells and pulls power from high cells. They don't have overcurrent protection for themselves and therefore could likely overheat if left a long time on a large pack that is very unbalanced... either that or one of the components was already about to fail from the factory and just quit. So I'd look at mounting where it can get some passive airflow and where the balance lead is not likely to rub on the busbars for peace of mind. Some inductive transfer units probably self limit their current but they balance from cell to cell like a bunch of 2s strings connected together which means that on larger (more series) packs, it is possible to have one cell high, then the next just a bit less high, all the way down to the low cell, the capacitor balancers will asymptotically approach perfect 0V difference balance because all cells equalize at once to the average cell voltage.

[@automateTec]

Couldn't a balancer just moniter/switch out charged cells?

[@johnydeep1094]

Think about heatsink on transistors.

[@MattNis1]

Could you please review the Ohmmu lithium after market battery for tesla model 3/y? It seems so expensive for such small battery. Is it possible to get the same thing from someone else?

[@mcsg_pelecan]

I purchased the same balancer... didn't last nearly as long as yours... I can think of better ways to "BURN" $50+ dollars!

[@AlexTorres-qv3hv]

Please also check that all bms should have a Voc threshold published......mppt CCs can let the voltage splike for couple of seconds which is common even for the most expensive CC's... acid vrla sla or gel batteries won't see these spikes...but the bms will cut out the CC from the battery after only 1 second of these overvoltage spikes letting the CC to ride freely at the pv Voc....and that's a concern when the bms encounters this voc at reconnect point,...it can be fried...

[@faustinpippin9208]

I have a all in one growat inverter and when a typical bms shuts of the battery when it discharges to much then......yes....the inverter shuts down.....if the inverter communicated with the bms to know that it should stop taking power from the battery then it would be the best but there is no standardization on the commutations ports and im to lazy to make it work so a active balancer is my only choice, and the inverter handles all the switching (you can set up all the voltages in the inverter including discharge and charge AMPs)

[@Gamingwithsamad838]

What about super capacitor Battery please test one

[@MegaCyrik]

But you really seemed to like the tiny 4s balancer in your other video. Is it a hate love relationship? Anyway.. i dont have a tiny charger to charge cells 1 by 1 as you love so much, so i just ordered a 10$ 4s for using on the cheap lifepo4 byd 12v 250ah for 240$ that i also just ordered. Lets see. Its for my fridge.. I'm tired of power outage. It will be fed by a 450watt panel. No more spoiled food.

[@RJ-cc1fz]

Could it have been that your cells were so far out of balance that the balancer went over it’s 5 amp limit?

[@MiniatureChickenChannel]

UH OH 4:43....nope that's fine 😅😅 Insert the "got him" meme dude laughin 😄😄 Yeah those balancer boards appear to be poo poo.

[@john_in_phoenix]

Active balancers are good for top balancing, then disconnect it.

[@robinhood4640]

I have been thinking of getting an active balancer, but still have doubts. Are you suggesting that it will be fine to just use it to top balance once a month, for example, to correct any discrepancies?

[@john_in_phoenix]

@@robinhood4640 Yes, it does make top balancing easy. Leaving it connected/running, that is actually counterproductive.

[@robinhood4640]

@@john_in_phoenix I have been balancing my lifepo4 battery pack manually once a year. Disconnecting everything and using my old lead acid batteries for a couple of days is a bit of a pain in the butt. Once everything is connected, all I'll need to do is put the connector in once the pack is charged and pull it out before the sun goes down. Certainly sounds like less work and i will not have the worries which have been the reason for my doubts. I'm laughing at myself for not thinking of this very simple way of avoiding eventual worries/problems. Thanks for sharing it.

[@john_in_phoenix]

@@robinhood4640 I was pretty much of the same opinion as Will, active balancers are counterproductive if left running all the time. They will actually unbalance your battery in the flat part of the curve (where you spend the most time). Off grid garage convinced me, they are quite useful for top balancing, just disconnect once done. Will and @Friedfox actually figured out why this one smoked (he has two BMS in series, and one did a cell voltage disconnect). They are a cost effective way to top balance, just be sure when you disconnect to insulate the leads properly, as Will notes, more wires men's more chances for something to go wrong. Done properly, you can just hook it back up and top balance a pack as often as you wish without any battery dissassembly.

[@robinhood4640]

@@john_in_phoenix I have 4 lifepo4 drop in batteries which all have an individual BMS. I have only recently converted from 4p to 2s x 2p, to increase the panels by increasing the volts without increasing the amps, for my mppt controller. Am i likely to have the same issue with the BMS fighting against each other?.

[@offgridamps]

I use one of these balancers the one thing I thought about is it wont turn off in a low temp disconnect situation, for example battery is below zero and you discharge it one of your cells is out of balance it flows energy to the low battery so effectively charging at 0c albeit at low rate.

[@egnegn123]

The problem with charging below 0C is lithium plating. But this happens with high to high currents only. The low current of active balancers doesn't really matter compared to normal charge current. If want to use the battery at this low temperature than you should think about heating battery to 10+ C anyway. If not, you should put it to storage by charging to 3.3V and disconnect everything.

[@offgridamps]

@@egnegn123 I think at 5amp its enough to do damage which these balancers are supposed to do

[@egnegn123]

@@offgridampsYou get this high balance current only with cell voltage difference well above 1V. In this case your BMS should have cut everything off long before.

[@offgridamps]

@@egnegn123 Yeah maybe ive seen mine at about 1.2amps not sure would it fuck things up at below zero, i mean its not great either way

[@olemissjim]

Awesome video! Love seeing a video where things don’t go by script. Tough to tell if it’s “chinesium problem” or maybe it needs a heatsink? Don’t you have a thermal camera (i just picked up a Flir v3 for the iPhone ) Please consider a follow up video, after seeing if the manufacturer will replace the unit.

[@billbucktube]

Is there a LiFePo replacement for a 12v battery for my van? Would it need cooling/heating to survive under-hood annual temperature swings?

[@georgesrisomsak9650]

Heat or extreme cold aren't good for lithium in general, and those actual numbers would depend on exact cell chemistry. I run a headway bank, but will have to stop charging when the temps get blow freezing. If you don't live in an area that gets below freezing, headway is great for stock voltage(14.4v). Can't go under the hood, you'll have to relocate it to the back, and do a front battery delete. OR.... Do like I did, and isolate them when key off, and parallel them when key on. When winter hits here, I'll pull the headway, and run lazy lead acid. You can build a heater setup for it, but more time and $ than it's worth in my application. I have heater pad for it and all, but it'll probably sit in a box forever...

[@billbucktube]

@@georgesrisomsak9650 I'd rather pay $300 for a battery that outlasts lead acid by 4 or 5 times. I live in central Florida so freezing is rare but heat can be tough. Making a battery to operate the newer high speed starters would seem to be easy enough.

[@carbonrrpilot]

the only thing lead acid is better than lifepo at is starting large combustion engines

[@kimmer6]

@@billbucktube A lead acid starting battery is a proven stupid proof unit that has decades of performance history. You can get an instant 600 amps into the starter for a few seconds with no BMS overload and kick out. IF you have an inverter or 12 volt appliances in the van, I would absolutely use a second set of LiFeP04 batteries back there. The other thing you need to consider is that if you deeply discharge a lithium battery, you might burn up your alternator recharging it. They take huge amounts of amps because of low internal resistance. The alternator may say 100 amps but their dirty secret is that they can only do it for short periods. With a lead acid or AGM battery under the hood, you can connect up the lithium battery to it with a DC-DC charger (I have the Renogy 40A unit and like it) and prevent overloading the alternator. My lithium batteries are behind the driver's seat in a much friendlier environment than under the hood. I hope this helps.

[@georgesrisomsak9650]

@@billbucktube headway is for you bud. My.lead acid doesn't do anything but look pretty under the hood. It doesn't start doing anything substantial till 12.5 volts or so, the lithium headway does ALL the work. I have a high current solenoid that has 2/0 cabling front to rear, the battery resides in the rear. Only because I don't want the lithium being dragged down by the agm, as it has a lower resting voltage. You could yard the lead acid, do a headway with 1/0 to the front from the back. Fuse the cable size properly, and you'll love the fast charging, efficient delivery and capability. I did my bank from battery hookup, $500 shipped. You get balance wires, already done to very high spec, a case, fan, solenoid, 48 headway cells, copper buss bars and all the hardware. Hell of a deal, just be sure you don't drop your wrench across the terminals. It'll vaporize🤣 Balance board, a little cutting of the buss bars and parallel the two groups and bam, 96ah of super burly 12v power. I pull 1000 amps + from this pack regularly, and it replaced large group 31 batteries. It holds voltage WAY better, lasts 15 years, no corrosion on wires and terminals, and holds voltage when cranking. The engine spins faster, my agm doesn't do anything. Cranking voltage is 13.8v, lead acid would be in the 11s. No brainer for you. What are you planning on running? There's a smaller setup for cheaper that would do you right too.. Lead acid is old tech. Heavy, slow charging, inefficient charge and discharge curves, high maintenance, requires replacement every few years, expensive, leaks acid, susceptable to vibration, and so on....I'll never buy another lead acid after going lithium. Trust me, you wont regret it, a little more upfront, saves you down the road. Meanwhile your enjoying unlimited current draw, high efficiency charging and discharging, lighter weight, and better value. I'm converting my ladies G8 this weekend as well, I'll load a video if you don't believe me. They are that much better. Two things... DON'T overcharge OR discharge THEM! 14.6 Volts MAX, 12.6V or so minimum. Enjoy the better part of 20 years of use! Car starts much faster, lost weight, gained power. For cheap. All wins in my book. Don't listen to the other guys, they don't have experience with the headway. Not a sales guy, just trying to help you get something good for your $. I'm more than pleased with my purchase. I'll be back for more, no doubt.

[@lekcadful]

Before plug in should be check wiring by multi-meter

[@williamhustonrn6160]

Hey Will, I have a question for you, there is a guy in my Marina who is a big solar installer for a lot of boat people that keep their boats there. He has his set up very differently and wanted to get your opinion. He has a sailboat that is converted to electric with dual 96v electric outboard motors replacing the diesel engines. Instead of having all his solar going to a single charge controller, he said he had too many issues with BMS's burning up on him, so his battery bank is 8 x 12v battleborn batteries wired up in 96v. He has a victron small 150v solar charge controller mounted on each battery with 8 in total. He showed me how each controller is setup in 12v battery mode/lithium and shares the common voltage from the PV combiner box. So all 8 of his charge controllers share the solar panel voltage based on how he showed it to me and each battery has its own Victron charge controller dedicated to charging that one single battery. He said they act as a BMS in a way because the battery with the lowest SOC will draw more of the amperage from the PV circuit vs the others until they are all charged. On the boat, he had all the PV wired up to a single circuit, then each charge controller was wired to the PV combiner box, splitting the PV voltage across all 8 charge controllers. He said they were the cheaper victron models, only about $25/each and he keeps 2 spares onboard. I just was curious what your opinion was on that setup, i have a sailboat also and been dreaming of ditching the old diesel motors and going EV, but instead of dual electric outboards like he did.. i was thinking of just going 1 single and installing the mounting plate, so if needed i could take the outboard off my dingy to push the boat..

[@easylooker]

Why do you have to top balance if you are not going beyond 82% full?

[@WillProwse]

I charge to 98%

[@easylooker]

@@WillProwse I mean not for yourself but on the diysolarforum lot of guys don't go beyond 82% or below 17% so why do a top balance? I've always wondered this

[@upnorthandpersonal]

@@easylooker Imaging one cell at 40%, another at 60%. These have the same voltage, and you're on average now at 50% - so no problem. Now you want to charge to 80% (let's assume we know how to do this with a shunt or something). We're adding 30%. one cell that was at 40% is now at 70%, the other one is now at 90% (i.e., too high for the 80% target - remember, this is 80% across all cells we want). Going towards this 90% on that cell will also increase stress disproportionately to this cell compared to the other one. Top balancing solves this.

[@easylooker]

@@upnorthandpersonal Is this why some are using balancers instead of just the bms?

[@upnorthandpersonal]

@@easylooker Or a BMS with built-in balancer. However, a balancer can only do so much since it's limited to how much current it can actually shift. Now assume you have a 40% state of charge difference between two 280Ah cells and we want to balance that - that's more than 50Ah to shift. With a 5A balancer (and assuming it does 5A continuously, which it won't) this takes 10 hours. And that's just those two cells - in a 48V system, you would have at least 16 cells. In other words, it will take a long, long time for a balancer to get your cells balanced when you didn't do a top balance first. After a top balance, the delta between cells is much smaller so that cells drifting apart can be brought back in balance even with the small balancer current.

[@electrickingzton7678]

i have an active balancer similar like that one on my 8s battery with 280 AH cells. I have new cells, i got the balancer just in case. That's unfortunate for yours.

[@whatmust8146]

I disagree. Active balancer is a must for especially pack that builds from recycle battery. That is my case. I had 200AH packs i built over the year i did not use any balance at all just manual voltmeter. Well they did not last long because of the imbalance and dropping too low situations. Well I wise up and start using the active balance now (capacitor type) and have a wifi camera to remotely monitor. Another benefit is that during use it will continue the active balance to equalize out each bank thus lengthen usage of the whole packs. A good active balance 5A or more must be used NOT the cheapie 1A type. Later on i will add the bms with remote monitor capability.

[@TRYtoHELPyou]

Fan cooling the balancer FTW

[@jaybrooks9829]

Maybe it overheated because you had the board sitting on the plastic container.. should have had the board on stand offs so there was airflow underneath

[@c-ccoates503]

Discharge balancer / active balancer interactions

[@HR-rt9nh]

Top Balance.... Done..

[@josepeixoto3384]

i'll bet the bottom touched some of the cells' terminals; and, there is a FOOLPROOF way to check your wiring before connecting the 2 plugs; you measure VOLTAGES , ALL 16 OF THEM; »»»» they MUST increase by 3.33 or close, from pin to pin; the multimeter black lead STAYS on the (black) wire B- , and you go from there, pin to pin, all the way to B16+ (of course, if you have a 16S) ; i guess the videomaker did not know much at the time.

[@dylanc9275]

I had one and it failed in weeks

[@georgesrisomsak9650]

Did it fail in the same fashion? Up in smoke?

[@dylanc9275]

@@georgesrisomsak9650 one of the transformers stopped working and would stay on

[@georgesrisomsak9650]

@@dylanc9275 thanks, good to know. Good for everyone to know, can't have failures like that with equipment, vehicles, rv's and homes potentially at risk. $1000 bucks on something quality is considered cheap in my opinion at that point.

[@matthewknight5641]

All the battery failures I've seen on youtube are almost always because of the balancer not doing its job or kinda working backwards. 1 time I saw a bad cell in a big pack but they also said that they thought it was because the balancer failed

[@matthewknight5641]

@@kreciq_klu bms and balancer is both the same. Bms has either active or passive balancer nearly always. Thanks for the correction lol

[@matthewknight5641]

@@kreciq_klu this whole conversation started by me saying I've seen where balancers that broke caused batteries to be damaged. You said... no its the bms breaking that causes damage.. bro when a balancer in a bms goes bad it damages cells by allowing them to go out of balance and causing the cells to go high or low and if over or under voltage don't catch it then it damages cells. I'm yet to see a bms that went bad that didn't have a problem with the balancing of cells. I've never had the issue myself but I I had two friends that had very expensive batteries have cells go bad after a balancer didn't do its job. And one friend that had a battery get screwed up from a balancer not stopping its balance at the balance low cut off point and the balancer kept continuing to balance threw the whole charge discharge cycle. It actually ended up making q couple cells swell up like a balloon. The bms did its job in shutting down due to low voltage but the balance circuits were fried. That's why I think balancers going bad is usually what messes up batteries. Yeah if a low or high voltage disconnect doesn't work right it'll screw up batteries for sure but almost always when that happens it starts with balance circuitry starting the problem. Everyone knows not all bms have alone features and some have active some have passive and some have all kinda cool features but I still and always will think 9 times outta 10 it's the balance part that's usually the weak link in these Chinese bms... well that and the fact that they are rated for way more amps than they can continually do. Like a 100 Amp bms probably don't need more than 60 amps run thru it so it don't get hot. 2 things other than cheap parts seem to be bad on about all Chinese electronics. They rate them as being safe with more amps than they actually are and also heat.. ok.. three things.. especially the bms's. Over ratings as far as amps, heat, and also starting with batteries that are not closely matched from the start. If a balancer in a bms has to work hard to keep cells in check then don't count on it being dependable cause over worked balancer is Destin to fail. And the bms should be the last line of defense to save that battery as far as over or under voltage. Anyways... good chat

[@mackfisher4487]

--------------- Smoke detector Will ------------------------- "Plan for the worst hope for the best" Your house is new enough to have multiple AC/battery backup smoke detector that are wired together through the AC wiring, add an additional compatible smoke detector in your Lab. Get an extra large fire extinguisher and sleep soundly.

[@RolopIsHere]

Every active balancer I got went on smoke eventually when charging, so I gave up on them and disconected them.

[@multilis2]

The idea imo is you don't ever charge or discharge batteries completely, just like in electric cars, that way you get ahead in the long-term

[@mhmdsaleh3502]

May be it must put in a ventilated place

[@sjdtmv]

Welcome to Cheech & Chongs Up in Smoke remake by Will Prowse

[@xdagasx4153]

I think you done something wrong,cos for me this active balancer works so good,balancing cells perfectly and fast... I would really reccomend those balancers,I use as well 6s balancers to charge battery insted to use balance charger cos it is balancing super accurate

[@AutisticMorty]

Maybe it needed a fan/heatsink and open ventilation to dissipate the heat. Could have been too much heat buildup in that tote. Might want to add some smoke alarms near your battery wall. Stay safe

[@robertmeyer4744]

Looks like spend the money for grade A cells and top balance from new . worth the extra money.

[@bopunsu]

mine only survived for less than an hour...