There are 3 separate circuits for 4 cell board, so some viewers said that balancing will only occur on adjacent cells. Some of my viewers said that the inductor is a resistor so its passive. If we had a board schematic it would be pretty obvious what is going on. Another viewer posted his video showing the lowest voltage cell rising in voltage, so is mine defective? I would imagine that at least one of my tests would cause my lowest voltage cell to rise a little bit, but it never did. Comment thread and other videos from other viewers can be found pinned on this video: ruclips.net/video/fEVQ_8DUpm4/видео.html Please let me know what you guys think! Would love to hear your thoughts. ~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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: williamprowsediysolar@gmail.com 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
Part of being a pioneer of DIY solar projects, is throwing money away on junk equipment (or ridiculously picky inverters) from time to time. We are the alpha testers for the tech that will be common in every home 20 years from now. It happens to all of us, dont feel too bad.
its an active balancer. I did your test but on a smaller scale. 4s 6ah lifepo4, it needs a 0.1v voltage difference to activate. I did 1 discharge test, and 1 charge test, it activated both times. My battery went from 0.12 voltage difference to 0.03 difference after charging. I don't know if it can do 1.2 amps, but it definitely does help a lot.
I've been designing my own active balancer using SEPIC switch modes. To achieve 1A of balance current is taking larger charge components and better smarts for control than this module is using. The benefits are good though as it is more efficient in power usage. Also you have the ability to balance on a discharge cycle as well as a charge cycle possibly giving you a little longer battery life.
Hello my friend. This happens because your batteries is almost same voltages, to use all balance power from the board of 1.2A - 1.5A the batteries must have much more voltage difference. I upload new video with testing this board, so you can see currents of etch sell.
I think that balancer uses ETA3000 chip. If so, then balancing kicks in at 100mV typical based on the datesheet of that chip. And balance current is minimum at 100mV adjacent cell difference and balance current goes higher as the delta goes higher up to 1.2A. I have one and it works.
According to the info for mine, the further out of balance the cells are, the higher the current transfer. They don't even do anything until there is 0.1v difference between cells anyway. I've found a 5A version on ebay and ordered it. It could speed up analysis drastically if you were to use 18650 cells rather than big LiFePO4. I plan to do this myself.
Yep, something to watch for is if it has the components of the board to do active voltage boosting to take charge from one and charge another one. Just the size of those are a dead giveaway that they don't and possibly they will bridge cells but that most times won't balance them they just stay the same. You will see the better ones have a little boost power supply circuit to increase the voltage differential between cells.
Thank you for sharing this with us. It's so nice to see someone being so honest. And I am sure glad that you are doing this. You're helping all who watch your videos so very much. You're saving us all time and money. Thank you!😊
Hello , as specs refer more the difference in voltage between battries more the drawing and pushing current upto 1.2a max , also first connect negative to positive one by one and always check polarity or it may smoke and also disconnect positive to negative to keep it on safer side
A complexity of logic in an active balancer is an order of magnitude higher than that of a passive one. A passive one is easy: measure, compare, discharge every cell except the lowest until no more difference. I would not begin to comprehend a logic of an active balancer, it would take a much smarter brain than mine to even model it! One thing is clear to me though, active balancers cannot be cheap.
An active cell balancer is basically a current limiter and paralel connection. If you connect a discharged and a fully charged battery together, smoke will come out of the wire, because it draws all the power in the world. These little boards limit the current from one cell to the other. That is it, you can build a less advanced one from junk for about 2$
Your dedication and investigative adroitness is second to none, and as always I enjoyed your watching your video. So Will, when are you going to begin doing destructive testing? It would add an "explosive" savoir faire to your testing format, and absolute necessity for wearing those super sexy glasses. LOL
You may want to try another round of testing on the cheap active balancer. That type of balancer gives more current based on the difference in voltage between adjacent cells. I believe yours is rated to hit its max for a cell-cell difference of 0.2 V (even though they start transfer at 0.1V). While the max current may be much lower than rated by the seller, there does appear to be genuine charge transfer going on (out of one cell and into another), and there certainly is on the one that I have tested.
The tiny pcb module does its job. It is just not designed to charge, but to balance. So the current increases in case of increasing voltage difference. if you use a prebalanced pack it should work. you also can use more than one in parallel because of the hysteresis. Adding them to a working battery pack is not the worst idea because of also low standby current. sorry for the bad english.
Also since the active balancer is using induction magnetic storage to transfere energy it might not be possible to measure with a clamp meter or a standard DMM. I've seen anotherone testing this as a 6s and having 1 volt difference in cells where only one was high and the other ones all increased in voltage with it on. But the 1.2a claim might be overestimated. Considering to buy one for testing
These active balancers are actually DC-DC buck converters. They funnel energy from the higher cell to the lower ADJACENT cell. Thus, if you brought down cell #3, it should funnel from cell #2 or cell #4. Also, these balancers balance faster, the bigger the difference between the cells. I would suggest you take a cell really low (like 0.5V lower) and then test to balance the pack with this balancer, under no load.
Please read the datasheet on the balancer. The chip is an ETA3000. It is a switch mode power supply and an active balancer, but it only balances between two adjacent cells when they are at different voltages with some hysteresis. So if you have say a 4S with the 4th cell at a low voltage it will take power from the third cell until the voltage between the 3rd and 4th cell are even. However that will then make cells 3 and 4 lower than the rest of the pack so it will take power from the second cell and move it to the 3rd until it has matched cell 2. It will then shuffle some power to 4 and pull from 1 to 2 and then 2 to 3... and keep shuffling power around until all the cells are balanced. Now its not quite as slow as it seems as it can move power from 1 to 2 and 2 to 3 and 3 to 4 at the same time, but that will only happen if all the cells are at different voltages. As far as the current, I don't know what it would take to get to the full 1.2A. Maybe they won't balance that quickly, but it probably take a large voltage difference between cells for it to run at the full current. Very much like you can't pump full current into a battery that is already charged. I have one and plan on measuring the currents to see if it ever does reach that max current rating. As far as testing you cant measure the current it is balancing with out the proper equipment. A digital mutil-meter will not work correctly for this circuit because of the burden voltage in the current shunt of the meter. Go look up burden voltage, but essentially the current sense resistor used in most DMMs will be large enough to create a significant voltage drop in the circuit you are trying to measure. Often that is not an issue, but in this case the balancer is very dependent on what the voltage between the cells are and changing the voltage it sees but adding in the large current sense resistor will mess up how the balancer runs and screw up your test. The hall effect sensor could work, but if the upper range is too high on the sensor, then it may not measure well at its low range. That may be why you only got 0.2 and no other readings, but if you checked the meter at currents below 1 amp and it measured good then its good. If it is measuring correctly then I would go back to the batteries probably need to have a larger voltage difference to balance at higher current. I forgot to mention, the transistor frying its from them trying to add more protection to the circuit, but may have caused an issue if you don't have all the wires hooked up. I think with this design you have to make sure everything is hooked up before you plug in the board. That definitely sucks about these boards. Overall your review is not too bad, these do seem to balance slowly.
Yeah great points but I realized after this video that active balancers are absolutely pointless. even for unmatched ir and capacity cell banks. So I don't use any of them. Waste of money
@@WillProwse I am new to battery packs so I am curious why you decided active balance is pointless. If you haven't please put up a video. I do know that in my case I have a 4s LiFePO4 pack that has one cell that is not so good and slowly discharges. I like having the balancer to keep the cell close, but also I don't really use the pack for anything. I did do a test last night on that active balancer I have (the same you tested in this video,) and found that the voltage difference is a big factor in the current. With a small voltage difference the current is low, but as it increases the current goes up. To test this I used my 4s pack which was at about 3.2V per cell. I started charging just the top #4 cell and hooked a low burden voltage current meter in the balance line for the #3 cell. Then measured the charge current moving down to that cell. I got up to 0.66 amps at about a 0.3V difference in the cells. I then started charging the #1 cell and put the current meter in the line for the #2 cell. That got about 0.96 amps of current at about 0.35V difference in the cells. It looks like these active balancers will work, but the charge current is slow. I plan on using them for small packs where I think the charge current should be enough to keep them in balance even under load, but for big packs it wouldn't do much.
Wondering how you would set up a system in a storage box; the type people put in front of their camping trailers or truck bed. Thoughts on best arrangement for set-up?
Wow! 👍👏 I been watching you since you started and today my friend you truly earned my huge thumsup and respect. What a great video, going into full details as far as actually testing products to the fullest, And not hesitating to express your true feelings about products that fall short of expectations...
Thanks Will great review.......My rule of thumb with Chinese stuff is to half the specs! e.g. Something that is 10A I always assume is 5A, also I see a lot of PWM controllers being passed off as MPPT too! Thanks to reviews like yours we are better informed, well done!
Try the active capacitor type. I just ordered one on Ebay. look up "Lithium battery Active Equalizer protection board 4S 5A Balance Li-ion Lifepo4". The capacitor one said it was good for up to 5 amps. Thinking that little Inductor type is just to small to do the amps it claims. I seen another similar one that said it was recommended for a 10ah battery and about 225ma of transfer. I don't think the inductor type uses resistors. The inductors was just getting hot transfering they are small after all.
use the flying capacitor one they are really true active balancer. they shuttle charge between the cells with caps and connecting the battery alternating-ly.
If it is using inductors, which it looks like it is, it is going to be a pulsating dc current, which is going to read as far less then what the peek current is.
Cool safety glasses, bruh! :P Glad you've got them. I had a PCB overload one time and shoot some small red molten bits flying past my head. Protect your eyes!
Maybe it only active balances while charging and maybe while powering stuff. Controlling the transistors and integrated circuits probably uses a lot of energy and it looks a lot easier to me to bypass batteries during charge/discharge than to actively feed one battery from another while they are otherwise just sitting there.
Oh I did a few cycles and even tested it previously and didn't seem to make a difference. This one is only triggered by difference in cell voltage, not by voltage. It can be at low soc or high SOC and it will still turn on
Thank you! You beat me to it! You deserve it. I love car audio, and it is great that you run your own tests. Sure is fun making RUclips videos of our own hobbies isn't it? Helping people out, building cool stuff, and making a living. Wouldn't want it any other way :D
Before we know if the balancer is working properly, test the current charging the lower cell with a bench charger that is the same voltage as the higher cell. You will be suprised that the current between the cells based on voltage difference is very low. There is only so much it can do because there is only 0.1v differencial when it starts. I have two of these and they work well. My tests indicate that with 0.1v difference, it can't push 1.2a between batteries.
On the little board, using LTO cell voltage the balance current was 60ma . You reading 80ma sounds correct because your at a higher voltage. If you read the specification it says 0-1.2A. :) Maybe it's a peak current pulse of 1.2A. My first board came in with a bad transistor and they sent a replacement. The board will dump energy cell 1 to 2 or 2 to 1 depending on the cell that drops .1v below the other cell. When the cell reached .05v difference the balance shuts off. This was verified with a bench supply and one cell. I would recommend you get a variable power supply to do testing , it will save you lots of time.
@@WillProwse This weekend I plan to test cascading the boards. If they work fine I don't see an issue with balance current of 60ma, after all it balances all the time!
Havent watched the full video yet, but the ampere of the balance depends on the voltage difference. Since you have next to no voltage difference, it does not do much. Try with 3 full and an empty cell. I have bought a 10s version myself, and the 1.2A is real, and its for every couple, not the combined power
I decided to test these out on a used LG Chem module battery that i got and it did raise the lower voltage cell up but it was 0.35 volts off from the highest cell. I wish i would have put a meter on it to see how much it was moving but it did bring the voltage up without me having a load or charging it. I don't know know if these work or not. Could you do more testing and see.
When one cell has internal resistance, add a shitload of external resistance to the other cells to balance them? Seems like a really inefficient way to do this. A herd is only as fast as its slowest buffalo.
after watching the last video I had a look around and found a capacitive cell balancer that would work as you want on ebay for about £20 - also a lot of resistive cell balancers calling themselves 'active'. I guess that's why your cell monitor claims active cell balancing. I've made my own cell balancer that does transfer power between cells using a 7-winding transformer, though it's only been under test for a week now. Shame the inductive balancer didn't work as expected...
Don't know what you tested, but I just tested the 3s board (Ver. 3.0) and at 180mV cell difference about 600 mA was transferred to the lowest cell. So they seem to work. B.T.W I'm a 75 year old Electrical Engineer from Luxemburg.
I have two more coming in the mail that I will test. Maybe I had a defective one. One guy has same results as you, and three other people have same results as my video, so I will get a new one and use power supply to increase voltage of a cell and see what happens. Thanks for letting me know
You most likely have a Buck-boost converter based cell-balancing circuit. that would use three inductors for 4 cells. If you disconnect one of the cells with a load on the battery the small diodes on the board will try and bypass the missing cell Maybe that were your smoke came from.
Damn. Did seem to be too good to be true without big capacitors. Thanks for doing this! Looks like we have another scam to look out for similar to PWM chargers labeled as MPPT. The 16S version of this balancer I ordered arrived today, and I've hooked it up to a 7S32P. The LEDS for 8-16 flash every second or so, but 1-7 remain dark, so not sure what's going on here. The instructions say that higher S balancers can be used with lower S packs, but don't explain how. On some BMSs the highest S of the battery goes to the highest S of the balancer. I've asked the vendor for clarification and waiting for a reply. It does say in the manual to connect 'obliquely', ie from negative first. Failing on missing cells I think is a symptom of bad design. I think I'll send them a link to this video too, and urge others to do too - it's absolutely not cool to mislead buyers. Meanwhile, there is an active balancer on aliexpress for $85 that appears to do what it says, given that it has a couple of supercaps on board for charge shuttling. You might like to test that too!
Hey, I know this comment isn't related to this video in general, but I had a question about when you compared the tesla battery pack from ebay to the other batteries. 1. Is the cost really 50 per kwh, as opposed to grid power costing on average 12 to 13 cents per kwh? And second, can the tesla packs be utilized in say, a 48 volt system, i think you are using 24v. (I am watching a lot of your videos and have your site to look over still) Thank you.
Daniel Timisan, the iCharger X6 does not transfer the energy from one cell to another cell of a battery-pack. It dissipates the energy. If balancing starts, the internal temperature is rising.
Considering wire size along with board design limits it does better than you could expect . Any resistors get hot , it's what they are design limited to do . Same with this small device . Personally , I just want to know what each cell is doing with this device . P.S. I ordered new cells using your Amazon link . Please let me know if you get credit . Thanks Mon , Thanks All
I mean they have inductors and all i ordered like 3 i think a 3s a 4s and a 7s because i have one of each but ill try having 1 full and 1 low and the rest in between and see what happens
Ya I ordered after your other video and a saw someone else with a big one with Bluetooth that could do upto like 20s or more but he was doing 6s if that one is better i may get one of those for my 7s thats my big one its about 100AH of used 18650s from laptops and hoverboards but I have not revived the balancers yet but ill try to let you know
Another good Will. Could it be to do with internal resistance of the individual batteries as they get close to full? Also, doesn’t active balancing require some sort of capacitors to load and unload from one cell to another to achieve this?
I got one of each of those devices for each of my 12V 100AH LiFePo4 packs after your other video. The plan was to use the active balancers to balance the pack and the battGo screen to see cell voltages. I haven't assembled the batteries yet, so the plan could be changed. I made a Y cable so I can plug both the battGo and the active balancer into the battery at the same time. I guess I should still put both on there and set the battGo to balance as well. It won't balance as fast as expected, but will probably balance the pack eventually. Or would you do something different?
For there to be a chance of this ABMS to balance at 1.2 amps you'll need to have a voltage difference of at least 1 volt. The closer the voltages are to each other the less it should draw the further apart thay the more it should draw. I have never used one of these but have tested the del green ABMS and this is how they work
First your kits are Great on Ebay...2nd i am not ready yet but do you do installs i pay for someone to aid in installing solar on roof and do cuts you need..and how you want them..?
Well how would an active balancer work? So you have a few tenths of a volt and you connect low to high then the current is going to be (delta V)/R. I don't think that is going to amount to much. The only way to push more current would be to raise the voltage of the highest cell with a converter to make delta V bigger. I doubt these things are than complicated. What you can do is manually connect the highest to the lowest and measure the current. That will give you an indication of what the max current is going to be even if the thing was working as an active balancer. The balancer is not going to give you a bigger current transfer than a direct connection.
I'm going to offer some numbers and Ohm's law as a reason why the active cell balancer isn't pushing 1.2 amps. If I understand your initial setup correctly, you had your "strong" cell at 3.28v and the weak one at 3.25v. That's a difference of 0.03v and you're trying to equalize them with a 1.2 amp current. The only way this is possible (with 100% efficiency of eq board) is if the circuit resistance has a maximum of 25 milli-ohms. That includes both battery cells' internal resistances & that seems awfully low. Being your current draw was about 0.2 amps with a .03v difference, this calculates to 150 milli-ohms (75 per cell). That number seems still a bit low, but plausible for a LiPo cell. The take-away is, there has to be a significant voltage difference between cells before 1.2 Amps can be expected. Ohm's law cannot be ignored.
Just checking in to see how you've been Will. Are you still in the SD area? You still at the first awesome place that you rented with the gorgeous outdoor spaces? Just wondering if you're still happy & living the good life. Take care.
Try searching on Aliexpress for "QNBBM 4S active voltage equalizer balancer". They run $75 at the moment. I have two that been working flawlessly for me on some used CALB180 LFP 4S batteries I have assembled. The claimed up to 6A balancing current is real... my cells are typically within 2 millivolts. Now I just have to finalize the protection side of my build .. Leaning towards smart Victron products, but man you have to pay up for that stuff.
@Paper Tiger It hard to stay away from them. I've come full circle. But I am sold on Will's prismatic cells. Cant get Amazon here in Australia but I can get them directly from China.
Hi Will. This question is about your solar for beginner videos. I was wondering if i could pick your brain on electrical having trouble finding a detail answer. I am converting a 20 ft enclosed cargo trailer. Starting from scratch. I have a propane onan 4k generator, I am going to buy 2 6v batteries later 4, I order the 55 amp wfco power center that has ac/dc and multi stage converter built in, order a 30 amp plug (if ever shore hook up but mostly boon docking in desert) and was going to order a pure sine 2000w inverter. I was going to wait on the solar setup to pay-off some of the build cost first. Right now really struggling trying to figure out how to wire the inverter in so i can use tv, outlets, coffee (basically everything except AC and microwave) without generator, without it activating the charger in the built in ac/dc panel with converter or loosing all of 12 volt by turning off the converter(lights etc). the 4 different inverter wiring method article gives me a little bit of info. Since I cannot seem to figure out method 1 or 4 i was going to just make dedicated outlets if i couldnt figure it out so method 3... I do plan to add 400 watt solar in future with mppt controller and 2 more 6 volt batteries. But for now I cannot figure this out. I know it requires a transfer switch or possibly manually doing something? Any help you can give would be great. Thanks Keith.... some more info have a 3 way fridge (12 volt, propane, and 110), single dometic 15000 btu ac, 700 watt microwave, have bought my wiring, outlets, etc yet. Also have not bought the inverter yet. I really appreciate any help you can give.
keith minnicks A suggestion check into 18650 batteries in stead of 6 volt batteries. You will get more bang for you buck.. don’t forget fuse on out put of battery within 18” of battery, closer the better then connected to inverter and fuse or breaker after inverter.
A true active cell balancer would be individual boost circuits for every cell, so the boosted voltage from the highest cell can be fed to the lowest cells. A passive cell balancer will simply switch resistors between the cells, via transistors. This is an ineffective way to balance cells, as the balance current is low, getting lower as the cells voltage nears equalization, and the cells can never be perfectly balanced, as there's going to be some loss across the switching transistors.
These boards work fine BTW guys. The problem is that he's using them on LIFEPO4, and they are not designed for that. They have protection built in for low voltage cells to only transfer at 10% power to protect the cells until they get back up to 3.7V So pointless for LIFEPO4, but perfect for 18650 packs etc. Though there are 2 varieties of this board, and one of them advertises as 1.2a but is only setup to do 1A or something i believe. You just need to change the resistor value to change the current if you need to i guess.
Will is an 'Active' cell balancer push more current to a low battery or does it just 'burn off' excess voltage on the high cell? Maybe there is no such thing as an 'Active' balancer the why people think it is. If you look at serious BMS like Batrium, even their 'long mons' all use 'burn off' to manage, so I think 'Active' is just being used as a name.
@@WillProwse Oh I didn't know that. Have you seen Bruno's new Batruim long mon instal vid? Will you were sure living the dream when you were at EVWest, it was awesome to see :)
@@WillProwse Oh, I wonder if the extra cost is worth the savings that you would get from not 'burning' off the power. A difficult to calculate on a small scale like RV. Of course big commercail power application would not just burn of the power because that heat would have to be cooled by even more power use.
All a top balancer does is nudge the top off the high cells with a parallel mosfet and resistor - it's no magic machine. Cell balancing can take place over a whole week, there's no rush, and once balanced they only need the tiniest nudge to stay there.
Me and a lot of my viewers are not just correcting for cell drift or adding cells to a pack... We are doing bottom and top balancing for specified applications, with large batteries, quickly. If all we were concerned about was basic reasons for balancing, no one needs these. Especially for LiFePO4, totally pointless. But that's not why we are doing it. We also want to use old used, mismatched cells, and increase capacity with active balancing. That's why. So there is a huge rush in our application. Otherwise I'll just use a BMS balancer.
I a quite sure, these are the boards I have tried out, thinking they were active balancing boards, 20 percent of the boards I used, have failed, the transistors burn out. :( under normal use over time.
The BarreryGo is automatic balancer, it draws 0.2 A from the cells that are higher voltage only. You can feel it heat up when it works. This is designed to balance drone batteries (small) Over days it works on my 10kwh 7s licoo2 system, I consider it to be just a monitor, yes it does balance ridicule power, but the main point is to give quality accurate information on the packs. Its usb power is also useful for example to run fans for cooling or just to keep an air flow an all equipments. I don't know any source for a balancer that would take current from one cell and charge another. I'm not even sure if Electrodacus controllers can do that ?
My opinion on having a battery that is balanced is this : as long as you don't push things (keep a licoo2 under 4.15V and above 3.10V) you don't need a perfectly balanced pack. In my experience a very small imbalance stays there, the modules do go up and down is harmony. Careful tho : things can fail always so the best is to keep an eye on it daily. The pack is secured by fuses and breakers, and both the charge controllers and the inverters are set to cutoff at restrictives voltages of 28,7V and 21,7V. I have also a bunch of fire extinguishers in both CO2 and powder, and also two options to evacuate the building. relying on a BMS for a big system is not a good idea : you don't know what is in the box. It does not replace a thermal camera, it does not replace a real fuse, etc. I prefer to take the risk of not using it than having an unknown box failing on me in an unknown manner. A year in, I never saw more than 0,012 V imbalance, and the pack lives like that. it oscillate between 0,007 and 0,012 V imbalance, and frankly, I do not call that an imbalance ! (10kwh 7s made of old recycled 18650)
@@AlexandreLollini oh for lithium iron phosphate we don't need to balance daily at all. The cells will not drift at all. we are not using active balancers for that reason. We are using them for specific application such as top and bottom balancing a new pack or using mismatched cells. We don't need a balancer at all really for normal everyday use for solar at our c rates. I cover this a lot in a few videos on LiFePO4 videos
I know that LiFePO4 is way more durable and stable for stationary use and solar etc. If I use LiCoO2 18650 it is only because of availability and price of those I recover and reconditions. While I know I will get way less cycles out of them, that is what I can afford and can do right now. My car has a 12V LiFePO4 and it is going strong (9 years in) == I will change the car, keep the same battery !
I just bought that ISDT cell monitor, after many hours of balancing, i couldn't see any reasonable result. Thanks for the test, i don't think I'll be buying that Chinese so called active balancer for now.
if i had to make an active balancer, i would suck at the highest voltage battery and pump it to the "high" voltage rail... i mean: if u suck at a battery and pump it to another battery u would need a lot of good switches and something like a charge pump topology...
I see, these don't work as you said.. that's prob why you moved it to private. But can you do a new video on how to probably balance these prismatic batteries?
There are 3 separate circuits for 4 cell board, so some viewers said that balancing will only occur on adjacent cells. Some of my viewers said that the inductor is a resistor so its passive.
If we had a board schematic it would be pretty obvious what is going on. Another viewer posted his video showing the lowest voltage cell rising in voltage, so is mine defective? I would imagine that at least one of my tests would cause my lowest voltage cell to rise a little bit, but it never did.
Comment thread and other videos from other viewers can be found pinned on this video: ruclips.net/video/fEVQ_8DUpm4/видео.html
Please let me know what you guys think! Would love to hear your thoughts.
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Part of being a pioneer of DIY solar projects, is throwing money away on junk equipment (or ridiculously picky inverters) from time to time. We are the alpha testers for the tech that will be common in every home 20 years from now. It happens to all of us, dont feel too bad.
if you want more accuracy when measuring small current wind more turn on your current sensor then divide the reading by the number of turn
when you find a true active cell balancer.. please make a video.
Thanks for digging deeper on this puzzle
its an active balancer. I did your test but on a smaller scale. 4s 6ah lifepo4, it needs a 0.1v voltage difference to activate. I did 1 discharge test, and 1 charge test, it activated both times. My battery went from 0.12 voltage difference to 0.03 difference after charging. I don't know if it can do 1.2 amps, but it definitely does help a lot.
I've been designing my own active balancer using SEPIC switch modes. To achieve 1A of balance current is taking larger charge components and better smarts for control than this module is using. The benefits are good though as it is more efficient in power usage. Also you have the ability to balance on a discharge cycle as well as a charge cycle possibly giving you a little longer battery life.
Hello my friend. This happens because your batteries is almost same voltages, to use all balance power from the board of 1.2A - 1.5A the batteries must have much more voltage difference. I upload new video with testing this board, so you can see currents of etch sell.
This balancer was actually defective. I have another one that works great!
I think that balancer uses ETA3000 chip. If so, then balancing kicks in at 100mV typical based on the datesheet of that chip. And balance current is minimum at 100mV adjacent cell difference and balance current goes higher as the delta goes higher up to 1.2A. I have one and it works.
According to the info for mine, the further out of balance the cells are, the higher the current transfer. They don't even do anything until there is 0.1v difference between cells anyway. I've found a 5A version on ebay and ordered it. It could speed up analysis drastically if you were to use 18650 cells rather than big LiFePO4. I plan to do this myself.
Yep, something to watch for is if it has the components of the board to do active voltage boosting to take charge from one and charge another one. Just the size of those are a dead giveaway that they don't and possibly they will bridge cells but that most times won't balance them they just stay the same. You will see the better ones have a little boost power supply circuit to increase the voltage differential between cells.
Good point.
Thank you for sharing this with us. It's so nice to see someone being so honest. And I am sure glad that you are doing this. You're helping all who watch your videos so very much. You're saving us all time and money. Thank you!😊
Hello , as specs refer more the difference in voltage between battries more the drawing and pushing current upto 1.2a max , also first connect negative to positive one by one and always check polarity or it may smoke and also disconnect positive to negative to keep it on safer side
I had no idea of what this was but I’m interested anyway
DuckeyDave360 Will makes every subject interesting to watch!
Sherriff of Solar
A complexity of logic in an active balancer is an order of magnitude higher than that of a passive one. A passive one is easy: measure, compare, discharge every cell except the lowest until no more difference. I would not begin to comprehend a logic of an active balancer, it would take a much smarter brain than mine to even model it! One thing is clear to me though, active balancers cannot be cheap.
An active cell balancer is basically a current limiter and paralel connection.
If you connect a discharged and a fully charged battery together, smoke will come out of the wire, because it draws all the power in the world.
These little boards limit the current from one cell to the other. That is it, you can build a less advanced one from junk for about 2$
I hope your glasses work as advertised if you need them to, too. Your eyes are pretty valuable. Love your videos!
Your dedication and investigative adroitness is second to none, and as always I enjoyed your watching your video. So Will, when are you going to begin doing destructive testing? It would add an "explosive" savoir faire to your testing format, and absolute necessity for wearing those super sexy glasses. LOL
Saw you in Jehu's video, nice to see three of my favorite youtube creators together. I hope you gave Rich a hard time. 👍
You may want to try another round of testing on the cheap active balancer. That type of balancer gives more current based on the difference in voltage between adjacent cells. I believe yours is rated to hit its max for a cell-cell difference of 0.2 V (even though they start transfer at 0.1V). While the max current may be much lower than rated by the seller, there does appear to be genuine charge transfer going on (out of one cell and into another), and there certainly is on the one that I have tested.
The tiny pcb module does its job. It is just not designed to charge, but to balance. So the current increases in case of increasing voltage difference. if you use a prebalanced pack it should work. you also can use more than one in parallel because of the hysteresis. Adding them to a working battery pack is not the worst idea because of also low standby current. sorry for the bad english.
Will now you're building bigger batteries for your new house you should have an eye on the qnbbm balancers on ae. They do active balancing.
I just read in the item description,the hav asked to use thicker wire for balancing to reach 1.2amps
Also since the active balancer is using induction magnetic storage to transfere energy it might not be possible to measure with a clamp meter or a standard DMM.
I've seen anotherone testing this as a 6s and having 1 volt difference in cells where only one was high and the other ones all increased in voltage with it on.
But the 1.2a claim might be overestimated.
Considering to buy one for testing
I think a lot has to do with the size of the batteries the amp hour size, the ones your using may be to much for the balancer to work that fast.
These active balancers are actually DC-DC buck converters. They funnel energy from the higher cell to the lower ADJACENT cell. Thus, if you brought down cell #3, it should funnel from cell #2 or cell #4. Also, these balancers balance faster, the bigger the difference between the cells. I would suggest you take a cell really low (like 0.5V lower) and then test to balance the pack with this balancer, under no load.
Please read the datasheet on the balancer. The chip is an ETA3000. It is a switch mode power supply and an active balancer, but it only balances between two adjacent cells when they are at different voltages with some hysteresis. So if you have say a 4S with the 4th cell at a low voltage it will take power from the third cell until the voltage between the 3rd and 4th cell are even. However that will then make cells 3 and 4 lower than the rest of the pack so it will take power from the second cell and move it to the 3rd until it has matched cell 2. It will then shuffle some power to 4 and pull from 1 to 2 and then 2 to 3... and keep shuffling power around until all the cells are balanced. Now its not quite as slow as it seems as it can move power from 1 to 2 and 2 to 3 and 3 to 4 at the same time, but that will only happen if all the cells are at different voltages.
As far as the current, I don't know what it would take to get to the full 1.2A. Maybe they won't balance that quickly, but it probably take a large voltage difference between cells for it to run at the full current. Very much like you can't pump full current into a battery that is already charged. I have one and plan on measuring the currents to see if it ever does reach that max current rating.
As far as testing you cant measure the current it is balancing with out the proper equipment. A digital mutil-meter will not work correctly for this circuit because of the burden voltage in the current shunt of the meter. Go look up burden voltage, but essentially the current sense resistor used in most DMMs will be large enough to create a significant voltage drop in the circuit you are trying to measure. Often that is not an issue, but in this case the balancer is very dependent on what the voltage between the cells are and changing the voltage it sees but adding in the large current sense resistor will mess up how the balancer runs and screw up your test.
The hall effect sensor could work, but if the upper range is too high on the sensor, then it may not measure well at its low range. That may be why you only got 0.2 and no other readings, but if you checked the meter at currents below 1 amp and it measured good then its good. If it is measuring correctly then I would go back to the batteries probably need to have a larger voltage difference to balance at higher current.
I forgot to mention, the transistor frying its from them trying to add more protection to the circuit, but may have caused an issue if you don't have all the wires hooked up. I think with this design you have to make sure everything is hooked up before you plug in the board. That definitely sucks about these boards.
Overall your review is not too bad, these do seem to balance slowly.
Yeah great points but I realized after this video that active balancers are absolutely pointless. even for unmatched ir and capacity cell banks. So I don't use any of them. Waste of money
@@WillProwse
I am new to battery packs so I am curious why you decided active balance is pointless. If you haven't please put up a video. I do know that in my case I have a 4s LiFePO4 pack that has one cell that is not so good and slowly discharges. I like having the balancer to keep the cell close, but also I don't really use the pack for anything.
I did do a test last night on that active balancer I have (the same you tested in this video,) and found that the voltage difference is a big factor in the current. With a small voltage difference the current is low, but as it increases the current goes up. To test this I used my 4s pack which was at about 3.2V per cell. I started charging just the top #4 cell and hooked a low burden voltage current meter in the balance line for the #3 cell. Then measured the charge current moving down to that cell. I got up to 0.66 amps at about a 0.3V difference in the cells.
I then started charging the #1 cell and put the current meter in the line for the #2 cell. That got about 0.96 amps of current at about 0.35V difference in the cells.
It looks like these active balancers will work, but the charge current is slow. I plan on using them for small packs where I think the charge current should be enough to keep them in balance even under load, but for big packs it wouldn't do much.
ruclips.net/video/cmZ-_sRnGj8/видео.html
@@trottingwolf watch this video
Wondering how you would set up a system in a storage box; the type people put in front of their camping trailers or truck bed. Thoughts on best arrangement for set-up?
Awesome, active video, William! Thank you so much
Wow! 👍👏 I been watching you since you started and today my friend you truly earned my huge thumsup and respect.
What a great video, going into full details as far as actually testing products to the fullest, And not hesitating to express your true feelings about products that fall short of expectations...
finding a active balancer which is affordable has been impossible.. thanks for sharing
Thanks Will great review.......My rule of thumb with Chinese stuff is to half the specs!
e.g. Something that is 10A I always assume is 5A, also I see a lot of PWM controllers being passed off as MPPT too!
Thanks to reviews like yours we are better informed, well done!
Total Awesomeness William
Your my man....
Try the active capacitor type. I just ordered one on Ebay. look up "Lithium battery Active Equalizer protection board 4S 5A Balance Li-ion Lifepo4". The capacitor one said it was good for up to 5 amps. Thinking that little Inductor type is just to small to do the amps it claims. I seen another similar one that said it was recommended for a 10ah battery and about 225ma of transfer. I don't think the inductor type uses resistors. The inductors was just getting hot transfering they are small after all.
use the flying capacitor one
they are really true active balancer. they shuttle charge between the cells with caps and connecting the battery alternating-ly.
Thanks for ur honesty will. Hope landlord hasn't raised your rent.
KenDroid66 yes I know what you mean. I hate it when complaining is done to God on such trivial and meaning less feeling that someone is having.
If it is using inductors, which it looks like it is, it is going to be a pulsating dc current, which is going to read as far less then what the peek current is.
The less differance in voltage, the less amps of tranfer. They do work much better than traditional bms's
Cool safety glasses, bruh! :P Glad you've got them. I had a PCB overload one time and shoot some small red molten bits flying past my head. Protect your eyes!
Maybe it only active balances while charging and maybe while powering stuff. Controlling the transistors and integrated circuits probably uses a lot of energy and it looks a lot easier to me to bypass batteries during charge/discharge than to actively feed one battery from another while they are otherwise just sitting there.
Oh I did a few cycles and even tested it previously and didn't seem to make a difference. This one is only triggered by difference in cell voltage, not by voltage. It can be at low soc or high SOC and it will still turn on
So close to 100k subs! Great video as always, keep them coming
Thank you! You beat me to it! You deserve it. I love car audio, and it is great that you run your own tests. Sure is fun making RUclips videos of our own hobbies isn't it? Helping people out, building cool stuff, and making a living. Wouldn't want it any other way :D
Before we know if the balancer is working properly, test the current charging the lower cell with a bench charger that is the same voltage as the higher cell. You will be suprised that the current between the cells based on voltage difference is very low. There is only so much it can do because there is only 0.1v differencial when it starts. I have two of these and they work well. My tests indicate that with 0.1v difference, it can't push 1.2a between batteries.
Good to know! I was going to use this on a build. Thx
On the little board, using LTO cell voltage the balance current was 60ma . You reading 80ma sounds correct because your at a higher voltage. If you read the specification it says 0-1.2A. :) Maybe it's a peak current pulse of 1.2A. My first board came in with a bad transistor and they sent a replacement. The board will dump energy cell 1 to 2 or 2 to 1 depending on the cell that drops .1v below the other cell. When the cell reached .05v difference the balance shuts off. This was verified with a bench supply and one cell. I would recommend you get a variable power supply to do testing , it will save you lots of time.
Good point, that's way easier method haha! I wasted so much time. Thank you :D
@@WillProwse This weekend I plan to test cascading the boards. If they work fine I don't see an issue with balance current of 60ma, after all it balances all the time!
I tried it with 4 18650 cell in series and it worked for me, it charged the lowest cell from 2.8 to 3.67
Havent watched the full video yet, but the ampere of the balance depends on the voltage difference. Since you have next to no voltage difference, it does not do much.
Try with 3 full and an empty cell.
I have bought a 10s version myself, and the 1.2A is real, and its for every couple, not the combined power
I decided to test these out on a used LG Chem module battery that i got and it did raise the lower voltage cell up but it was 0.35 volts off from the highest cell. I wish i would have put a meter on it to see how much it was moving but it did bring the voltage up without me having a load or charging it. I don't know know if these work or not. Could you do more testing and see.
When one cell has internal resistance, add a shitload of external resistance to the other cells to balance them? Seems like a really inefficient way to do this. A herd is only as fast as its slowest buffalo.
I think its 1.2A on the extreme bottom-top voltage differential.
after watching the last video I had a look around and found a capacitive cell balancer that would work as you want on ebay for about £20 - also a lot of resistive cell balancers calling themselves 'active'. I guess that's why your cell monitor claims active cell balancing. I've made my own cell balancer that does transfer power between cells using a 7-winding transformer, though it's only been under test for a week now. Shame the inductive balancer didn't work as expected...
Don't know what you tested, but I just tested the 3s board (Ver. 3.0) and at 180mV cell difference about 600 mA was transferred to the lowest cell.
So they seem to work.
B.T.W I'm a 75 year old Electrical Engineer from Luxemburg.
I have two more coming in the mail that I will test. Maybe I had a defective one. One guy has same results as you, and three other people have same results as my video, so I will get a new one and use power supply to increase voltage of a cell and see what happens. Thanks for letting me know
@@WillProwse we're excited to see the next test you will make for this Will!
Dude!!! Do not let out the magic smoke!!!!!!!!!
You most likely have a Buck-boost converter based cell-balancing circuit. that would use three inductors for 4 cells. If you disconnect one of the cells with a load on the battery the small diodes on the board will try and bypass the missing cell Maybe that were your smoke came from.
Have you tried Victron balancer?
I think you should test with lithium ion. dV has to be high to achieve 1.2amp balancing
Damn. Did seem to be too good to be true without big capacitors. Thanks for doing this!
Looks like we have another scam to look out for similar to PWM chargers labeled as MPPT.
The 16S version of this balancer I ordered arrived today, and I've hooked it up to a 7S32P. The LEDS for 8-16 flash every second or so, but 1-7 remain dark, so not sure what's going on here. The instructions say that higher S balancers can be used with lower S packs, but don't explain how. On some BMSs the highest S of the battery goes to the highest S of the balancer. I've asked the vendor for clarification and waiting for a reply.
It does say in the manual to connect 'obliquely', ie from negative first. Failing on missing cells I think is a symptom of bad design.
I think I'll send them a link to this video too, and urge others to do too - it's absolutely not cool to mislead buyers.
Meanwhile, there is an active balancer on aliexpress for $85 that appears to do what it says, given that it has a couple of supercaps on board for charge shuttling. You might like to test that too!
Yes that other one on AliExpress looks awesome! Might need to get one soon. And yes, I agree with your points
@@WillProwse I look forward to your results and analysis!
If you think about how a BMS is connected how would one cell feed in another one ?. It can only work by drawing power away from higher cells.
Hey, I know this comment isn't related to this video in general, but I had a question about when you compared the tesla battery pack from ebay to the other batteries. 1. Is the cost really 50 per kwh, as opposed to grid power costing on average 12 to 13 cents per kwh? And second, can the tesla packs be utilized in say, a 48 volt system, i think you are using 24v. (I am watching a lot of your videos and have your site to look over still) Thank you.
iCharger x6 has 2A active balancer but it's around 100$ ... you do get a charger with it too that is pretty cool
Daniel Timisan, the iCharger X6 does not transfer the energy from one cell to another cell of a battery-pack. It dissipates the energy. If balancing starts, the internal temperature is rising.
@@scooterandre you are right .. just run a test again today and it is NOT active ... it is def passive , I was wrong, thanks for pointing it out
Considering wire size along with board design limits it does better than you could expect . Any resistors get hot , it's what they are design limited to do . Same with this small device . Personally , I just want to know what each cell is doing with this device .
P.S. I ordered new cells using your Amazon link . Please let me know if you get credit . Thanks Mon , Thanks All
I mean they have inductors and all i ordered like 3 i think a 3s a 4s and a 7s because i have one of each but ill try having 1 full and 1 low and the rest in between and see what happens
Yeah let me know
Ya I ordered after your other video and a saw someone else with a big one with Bluetooth that could do upto like 20s or more but he was doing 6s if that one is better i may get one of those for my 7s thats my big one its about 100AH of used 18650s from laptops and hoverboards but I have not revived the balancers yet but ill try to let you know
Another good Will. Could it be to do with internal resistance of the individual batteries as they get close to full? Also, doesn’t active balancing require some sort of capacitors to load and unload from one cell to another to achieve this?
I got one of each of those devices for each of my 12V 100AH LiFePo4 packs after your other video. The plan was to use the active balancers to balance the pack and the battGo screen to see cell voltages. I haven't assembled the batteries yet, so the plan could be changed. I made a Y cable so I can plug both the battGo and the active balancer into the battery at the same time. I guess I should still put both on there and set the battGo to balance as well. It won't balance as fast as expected, but will probably balance the pack eventually. Or would you do something different?
Time to find a true active balancer, nice video Will your doing allot over their to keep us informed keep up the good work.
For there to be a chance of this ABMS to balance at 1.2 amps you'll need to have a voltage difference of at least 1 volt. The closer the voltages are to each other the less it should draw the further apart thay the more it should draw. I have never used one of these but have tested the del green ABMS and this is how they work
I could throw them out of balance at high SOC and test it again. I have another one in the mail. Good point
Good point
@@WillProwse I'd love to know as these are so much cheaper in cost vs. the del green
This ali shop also has a 24s bluetooth enabled balancer which actually works (aktive!).
First your kits are Great on Ebay...2nd i am not ready yet but do you do installs i pay for someone to aid in installing solar on roof and do cuts you need..and how you want them..?
Well how would an active balancer work? So you have a few tenths of a volt and you connect low to high then the current is going to be (delta V)/R. I don't think that is going to amount to much. The only way to push more current would be to raise the voltage of the highest cell with a converter to make delta V bigger. I doubt these things are than complicated. What you can do is manually connect the highest to the lowest and measure the current. That will give you an indication of what the max current is going to be even if the thing was working as an active balancer. The balancer is not going to give you a bigger current transfer than a direct connection.
I'm going to offer some numbers and Ohm's law as a reason why the active cell balancer isn't pushing 1.2 amps. If I understand your initial setup correctly, you had your "strong" cell at 3.28v and the weak one at 3.25v. That's a difference of 0.03v and you're trying to equalize them with a 1.2 amp current. The only way this is possible (with 100% efficiency of eq board) is if the circuit resistance has a maximum of 25 milli-ohms. That includes both battery cells' internal resistances & that seems awfully low. Being your current draw was about 0.2 amps with a .03v difference, this calculates to 150 milli-ohms (75 per cell). That number seems still a bit low, but plausible for a LiPo cell.
The take-away is, there has to be a significant voltage difference between cells before 1.2 Amps can be expected. Ohm's law cannot be ignored.
Just checking in to see how you've been Will. Are you still in the SD area? You still at the first awesome place that you rented with the gorgeous outdoor spaces? Just wondering if you're still happy & living the good life. Take care.
Try searching on Aliexpress for "QNBBM 4S active voltage equalizer balancer". They run $75 at the moment. I have two that been working flawlessly for me on some used CALB180 LFP 4S batteries I have assembled. The claimed up to 6A balancing current is real... my cells are typically within 2 millivolts. Now I just have to finalize the protection side of my build .. Leaning towards smart Victron products, but man you have to pay up for that stuff.
That's awesome. I saw that one. Great to here your experience. I need to get one haha
@Paper Tiger It hard to stay away from them. I've come full circle. But I am sold on Will's prismatic cells. Cant get Amazon here in Australia but I can get them directly from China.
Is it possible that the cells need to be farther out of balance before it will push 1.2 amps to the lower balanced cell?
Old video, but those are advertised to balance 1.2 amps but dependent on voltage difference.
Yeah luckily they are worthless anyways. Check out my new videos on balancers. Waste of money
Cool glasses 👓
You had my thumb up at seeing no thumbs down - this must be epic :)
Hi Will. This question is about your solar for beginner videos. I was wondering if i could pick your brain on electrical having trouble finding a detail answer. I am converting a 20 ft enclosed cargo trailer. Starting from scratch. I have a propane onan 4k generator, I am going to buy 2 6v batteries later 4, I order the 55 amp wfco power center that has ac/dc and multi stage converter built in, order a 30 amp plug (if ever shore hook up but mostly boon docking in desert) and was going to order a pure sine 2000w inverter. I was going to wait on the solar setup to pay-off some of the build cost first. Right now really struggling trying to figure out how to wire the inverter in so i can use tv, outlets, coffee (basically everything except AC and microwave) without generator, without it activating the charger in the built in ac/dc panel with converter or loosing all of 12 volt by turning off the converter(lights etc). the 4 different inverter wiring method article gives me a little bit of info. Since I cannot seem to figure out method 1 or 4 i was going to just make dedicated outlets if i couldnt figure it out so method 3... I do plan to add 400 watt solar in future with mppt controller and 2 more 6 volt batteries. But for now I cannot figure this out. I know it requires a transfer switch or possibly manually doing something? Any help you can give would be great. Thanks Keith.... some more info have a 3 way fridge (12 volt, propane, and 110), single dometic 15000 btu ac, 700 watt microwave, have bought my wiring, outlets, etc yet. Also have not bought the inverter yet. I really appreciate any help you can give.
keith minnicks A suggestion check into 18650 batteries in stead of 6 volt batteries. You will get more bang for you buck.. don’t forget fuse on out put of battery within 18” of battery, closer the better then connected to inverter and fuse or breaker after inverter.
Hi mr will I am building a large 12 v 640 amp out of 8 cells of 320 amp each wish BMS do you recommend pls let me know .
A true active cell balancer would be individual boost circuits for every cell, so the boosted voltage from the highest cell can be fed to the lowest cells.
A passive cell balancer will simply switch resistors between the cells, via transistors. This is an ineffective way to balance cells, as the balance current is low, getting lower as the cells voltage nears equalization, and the cells can never be perfectly balanced, as there's going to be some loss across the switching transistors.
Agreed. Exactly
Really great video...very informative!!
These boards work fine BTW guys.
The problem is that he's using them on LIFEPO4, and they are not designed for that. They have protection built in for low voltage cells to only transfer at 10% power to protect the cells until they get back up to 3.7V
So pointless for LIFEPO4, but perfect for 18650 packs etc.
Though there are 2 varieties of this board, and one of them advertises as 1.2a but is only setup to do 1A or something i believe. You just need to change the resistor value to change the current if you need to i guess.
he needs to change the video to state this really
Every balance gadget I’ve used bleeds off higher cells all down to match the lowest cell. They are very slow as well.
Will is an 'Active' cell balancer push more current to a low battery or does it just 'burn off' excess voltage on the high cell? Maybe there is no such thing as an 'Active' balancer the why people think it is. If you look at serious BMS like Batrium, even their 'long mons' all use 'burn off' to manage, so I think 'Active' is just being used as a name.
No there are actual active balancers on the market. But they cost a lot
Batrium does not need much balancing power because it's just correcting for cell drift over time
@@WillProwse Oh I didn't know that. Have you seen Bruno's new Batruim long mon instal vid? Will you were sure living the dream when you were at EVWest, it was awesome to see :)
@@WillProwse Oh, I wonder if the extra cost is worth the savings that you would get from not 'burning' off the power. A difficult to calculate on a small scale like RV. Of course big commercail power application would not just burn of the power because that heat would have to be cooled by even more power use.
1.2/4(cells)=0.3A per balance lead right? so 0.2A would be about right?
Oh it should be per cell for that value
Is it maybe only working while charging?
Glad to see some active testing of these units. Also goad to see the safety glasses. Let’s hope they will never be needed. But of they are?! :)
Is the BMS that you demo'd for a solar array an active balancing system? Does it balance at all? Thanks.
It's really hard to replace Factory Smoke.
All a top balancer does is nudge the top off the high cells with a parallel mosfet and resistor - it's no magic machine. Cell balancing can take place over a whole week, there's no rush, and once balanced they only need the tiniest nudge to stay there.
Me and a lot of my viewers are not just correcting for cell drift or adding cells to a pack... We are doing bottom and top balancing for specified applications, with large batteries, quickly. If all we were concerned about was basic reasons for balancing, no one needs these. Especially for LiFePO4, totally pointless. But that's not why we are doing it. We also want to use old used, mismatched cells, and increase capacity with active balancing. That's why. So there is a huge rush in our application. Otherwise I'll just use a BMS balancer.
@@WillProwse I doubt balancers have any notion of the advanced applications for it. Sounds like big fat mosfet and arduino time.
Where can I get that clamp amp meter? Where does it get power from?
I a quite sure, these are the boards I have tried out, thinking they were active balancing boards, 20 percent of the boards I used, have failed, the transistors burn out. :( under normal use over time.
Based on ur previous video on this active balancer . I have ordered 17s. Now i feel it's a waste☹️ . Yet to receive it
I just ordered another one actually. I still like them haha its just not a true active balancer. Still very useful though
I wish I watched this before I bought this board dammit!
they work fine. Just not on LIFEPO4
EV - Customs showed they not only work, but beyond the rated amps. I think he got 1.5A
The BarreryGo is automatic balancer, it draws 0.2 A from the cells that are higher voltage only. You can feel it heat up when it works. This is designed to balance drone batteries (small) Over days it works on my 10kwh 7s licoo2 system, I consider it to be just a monitor, yes it does balance ridicule power, but the main point is to give quality accurate information on the packs. Its usb power is also useful for example to run fans for cooling or just to keep an air flow an all equipments. I don't know any source for a balancer that would take current from one cell and charge another. I'm not even sure if Electrodacus controllers can do that ?
Yeah I really like them as a monitor too. And yes there are true active balancers available but they cost quite a lot. They are on AliExpress
My opinion on having a battery that is balanced is this : as long as you don't push things (keep a licoo2 under 4.15V and above 3.10V) you don't need a perfectly balanced pack. In my experience a very small imbalance stays there, the modules do go up and down is harmony. Careful tho : things can fail always so the best is to keep an eye on it daily. The pack is secured by fuses and breakers, and both the charge controllers and the inverters are set to cutoff at restrictives voltages of 28,7V and 21,7V. I have also a bunch of fire extinguishers in both CO2 and powder, and also two options to evacuate the building. relying on a BMS for a big system is not a good idea : you don't know what is in the box. It does not replace a thermal camera, it does not replace a real fuse, etc. I prefer to take the risk of not using it than having an unknown box failing on me in an unknown manner. A year in, I never saw more than 0,012 V imbalance, and the pack lives like that. it oscillate between 0,007 and 0,012 V imbalance, and frankly, I do not call that an imbalance ! (10kwh 7s made of old recycled 18650)
@@AlexandreLollini oh for lithium iron phosphate we don't need to balance daily at all. The cells will not drift at all. we are not using active balancers for that reason. We are using them for specific application such as top and bottom balancing a new pack or using mismatched cells. We don't need a balancer at all really for normal everyday use for solar at our c rates. I cover this a lot in a few videos on LiFePO4 videos
I know that LiFePO4 is way more durable and stable for stationary use and solar etc. If I use LiCoO2 18650 it is only because of availability and price of those I recover and reconditions. While I know I will get way less cycles out of them, that is what I can afford and can do right now. My car has a 12V LiFePO4 and it is going strong (9 years in) == I will change the car, keep the same battery !
@@AlexandreLollini LiFePO4 in your car?! Nice!!!
I just bought that ISDT cell monitor, after many hours of balancing, i couldn't see any reasonable result. Thanks for the test, i don't think I'll be buying that Chinese so called active balancer for now.
Will is a lil giddy today, but still 30 IQ points smarter than me
What does it mean when one light is flashing red?
if i had to make an active balancer, i would suck at the highest voltage battery and pump it to the "high" voltage rail... i mean: if u suck at a battery and pump it to another battery u would need a lot of good switches and something like a charge pump topology...
I see, these don't work as you said.. that's prob why you moved it to private. But can you do a new video on how to probably balance these prismatic batteries?
this is for 18650s or mili ampere levels
Aw man will I already bought me one of these from your last video. Now I gotta return it
It still works better than other balancers. I'm still going to use them on my packs haha but yeah, not true active balancers. Sorry :( such a bummer
Sssooo, are you going to find and test some true active balancers?
I could but I don't need one really lol. But yeah, I guess I'll get one to make a video on it
@@WillProwse You'll have to actively balance whether it's worth it or not.