Can the active balancer save this battery? Impressive result!
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- เผยแพร่เมื่อ 20 ก.ย. 2024
- I always said I won't install an active balancer on my battery, so this is just a test, right?! It's a test! 😊This morning, the battery was at 12%SoC and very out of balance and I was wondering what would happen if we install the active balancer from Hankzor. Can it balance out these high capacity cells and save the battery from been disconnected by the BMS?
It's a test, right?
Hankzor active balancer:
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We have completed our mission and convertered the Anti-Balancer. 😂😂😂
M P, Ya, I did my part and suggested an active balancer several times on this and other channels.
Hahahaha, yeah im' really impressed so far. I'm going to wait until the battery is full though to see if it can hold up the positive start.
Can the active balancer setting be changed on the bms/active balancer hybrid interesting. So you could choose to have them balance on top or bottom only.
@@guy7gsa Unfortunately the Bluetooth balancer does not have Top or Bottom balance settings. The user can set the balance current from 0.2A up to the max which is 1, 2, 5, or 10A depending on the model as well as the Delta trigger voltage between cells from 0.001V to about 0.500V (1mv to 500mv). Cell balancing can also be turned off completely and the unit will only display cell voltages and internal resistance values.
Yeah I’m part of the pestering people too.📣
I bought an active balancer and never looked back. I'm disappointed with anyone that ever told me not to get one.
I agree. The best thing I’ve done for my battery bank.
Got it connected for a week now and it's been great so far.
That active balancer seems to be doing a great job. Have you estimated the extra Ah’s you get before the inverter/BMS cuts out?
@@kevinmills5293 that's not much. I would expect this to be far less than 5Ah, maybe 2-3Ah only in total.
Question...let say that I want to disconnect the active balancer...should I start by the small connector...and then follow with the large one? ...I'm talking of an active balancer 16 s....the connector with the ground has 10 pins...and the other connector has about 8 pins and no ground. Thanks
In theory, it actually makes sense that the pack voltage increased after active balancing (in your specific situation) because for a given amount of amperage transferred, the higher voltage cell would see a *smaller* voltage decrease compared to the voltage increase that the lower voltage cell would see. This is due to where each of those cells lie on the voltage curve, of course.
In reality, that would obviously depend on how efficient the balancer is.
As others said here in the comments. I missed that... absolutely correct
Well said!
Its prob just rounding
@@OffGridGarageAustralia BTW...When you were connecting the balancer, I think the diagram you were looking at was from the back side showing the mosfets not the capacitors.
@@mysterytechknowledge3664 that would make sense then. I'll check it again.
I’ve assembled a 4 cells battery with BMS only and I had a troublesome cell, it charges faster than the other 3 so the pack never could charge beyond 3.35v each cell. Until I added a 5A HELTECH active balancer and I was so happy to charge the cells to 3.65v each. Definitely the active balancer made a big difference in my case. It balances the cells at all times while the BMS balances the cells only when charging (not sure about when discharging) and with a small 200mv dissipation from the overcharged battery. The active balancer does not dissipate the over amps, it rather transfer the amps to the other cells with lower charge.
I had the same issue, love my active balancer 😁
how much quality having your videos!!! better than Galaxy Wars films. thank you, i enjoy a lot with this content.
Thanks a lot David. Very kind feedback 😊
Nice! I'm in the process of building my battery pack 8s with this active balancer and a Dali BMS... perfect timing! Thank you! Now I need the strength/guts to make a video of my setup (hurricane disaster vanbuild)... much easier said than done. You are my hero! (Smartshunt before BMS ... got it)
Thanks Christian. You can do it! 💪
Andy - love your work!
And your choice for sound effects crimping those balancer leads!
Hahaha, couldn't help myself... Thank you.
Also...Love your off the beaten path theories and practical testing to find the real results. It helps us to understand and build off your experiences!
Thank you, that's good feedback!
Overall voltage goes up because cell voltage is not a linear curve. Taking power from one cell to put into another does not mean you take x voltage from one cell and put it in another; in this part of the curve you get a big delta V with small changes in state of charge.
Beat me to it. this is 100% correct
That is correct, I didn't think about that. Thanks!
@@josepeixoto3384 Depends on where you are in the curve. In the case we were discussion, we were in the knee of the curve where it's very steep.
I would love to see you add a second balancer, the same one you have to see if it balances twice as fast. The balancer on your BMS does not use enough balance current to keep up with your massive bank.
Now after several days, all cells are still in balance. Once this has been achieved, I think the max 5A balance current is fine. As the balancer works 24/7 it does not need to be as fast. As seen in the video, it takes only 12h or so to get them all in line again.
yes many users suggest it, i think it's important when you have not good quality cells
I'm convinced. Two active balancers have been ordered!
I'm still testing....
For two different batteries or just to double them up?
Ok seeming how this a test i want to throw in the mix this question. Seeing what the balancer has done in 24 hours ( approximately ) ... can you have 2 balancers in parallel ? Would they fight or work together? Thanks again for your time!
Marc.
Why would you do this? Just for the sake of testing or to balance faster? I have read some comments here that people have done that and it seems to work.
Might be worth a test 🤔
Thanks for your time... using two balancers at the same time is yes a curiosity question but more for a point of the balancer works well only at the ends of the charge curve with any noticeable improvement and not in the middle of the flat section.... so the time spent at the ends is an extremely short window of opportunity.... unless I have misunderstood a balancers functions? Thanks for doing what you do andy!
Marc
I up vote this. Seriously this could be game changer for lots of people with mismatched cells. Please do this
Won't gain anything long run. Will it get the first day's balance done quicker, of course. Does it make any sense to leave it on there when 1 is plenty? No
I bought one active 24v 8S balancer a couple of weeks back because I had a couple of cells that will just outrun other cells when charging and will get very close to the overcharged level. The Smart BMS was never capable of balance them right. The active balancer solved this problem. I have it connected ALL the time now. It has performed amazingly.
Yeah, it looks like these things actually work quite well.
@@OffGridGarageAustralia Yes. In my case, I am using the inverter to power all of my essential loads in my home. The battery is cycle once a day and I need the cells to be as balanced as possible in a short period of time. This device help a lot. Specially when it is capable of moving 5A.
Just to add, you can get two of the active balancers and put them in parallel on the same balancing leads. They collide a lot at first, but over time they sync up with what they are doing.
@@SenatorPerry Good to know. Thx.
@@SenatorPerry Cannot imagine how this may work, but I will test it... 😉
I am convinved with the balancer. Thanks Andy
You and me both!
Glad you see the light a active cell balancer removes a ton of headache / hassle as I suggested several times its the way to go for simplicity and theyre power draw is almost a mute point the thing is it protects your cells from imbalance of cells dipping to low while others are in the good this can and will prolong the lifespan and use ability of your lithium cells its a win win for literally pennies compared to the rest of the hardware and such so where is the negative there is only positive in installing / using a active cell balancer.
It seems, I have to agree 😉
Du hast YT verstanden. Du bietest informatives und Unterhaltung in einem. Es macht Spaß Deine Videos zu sehen. Vielen Dank. Und mach weiter so. 🤗
Vielen herzlichen Dank fuer dein nettes Feedback. Dann will ich mal wieder ran, es gibt noch so viel zu entdecken und zu zeigen 🤳
Great video, looking forward to the top balancing video!
Yeah, it will take a while until I reach that with the current sun. Also supplying parts of the house already with power so the battery won't charge much during the day.
I use BMS with active 2A balancer - after nearly a year, checked three 280Ah batteries, they are 3-4milli-volt spread in each battery!
Thanks Andy, I agree with you, the balancing is a low cost and important piece of equipment to keep all the cells operating at peak performance, no runners.
Yeah, I like them very mich as well. Do you leave yours on all the time?
@@OffGridGarageAustralia YUP! I see no reason to turn them off, and the cells are always very well balanced - cost is nothing, benefits are great!
In a low current (solar, not vehicle) situation, i always suggest inductor balancers instead of capacitor ones. The reason is, that you always need to convert energy between magnetic and electric fields, to achieve low losses. But of course a capacititor model does the job and delivers current. Most of the time we store energy in a static voltage field, what means that a low loss energy transciever needs an inductor and a switch. Its a smps then. If we would use a rotation storage, inductive coupled to an also alternating voltage, then an good energy transformer would make use of capacitive energy delivery. Imho we all would throw away much less lithium batteries, if there would be active balancers in them and not only balancers which start to balance, when a cell is already in a harm region. Had a fresh battery for my scooter, which was weak aftr only 2 years. I opened the thing and the 24s lifepo was absolutely out of balance. I figured out, the top balance was not sufficient to hold the chargers amps. After adding an active balancer, i got it back to work since half a year. You do a great job there!
In my first test I charged the cells to 3.45V with a cell difference of greater than 100mV. The DALY BMS switched off charging at 3.5V for the highest cell and the internal balancer apparently had no effect. Then I connected the active balancer and you could watch the voltage difference decrease. It took less than 12 hours for the cells to balance at 3.45V with a voltage difference of 1mV. I was just as amazed as you.
Same experience here, the BMS's balancer just does nothing with these high capacity cells. Now, everything seems to be in balance no matter what I do.
thats what i´m talking about. active balancer´s are working very well in combination with a bms. bms for battery/cell protection and active balancer to balance, up to 6.5A.
That seems to be working well.
Are you the real Ingo von der Lippe? 🤔
@@OffGridGarageAustralia Yes, I´am the real one. The name of the other guy is Jürgen von der Lippe but his real name is Hans-Jürgen Hubert Dohrenkamp.
@@ltcmdrdata4611 Das hab ich jetzt verwechselt!
Oh man, i just love the work you are doing !!!! It has helped me a lot here in Finland where i built a 12 v 100 A battery of China lifepo cells wich i use in my fishing boat and is connected to the trolling motor. When the cells came in June, 3 cells where in balance and 1 was 0,35v higher, i bottom balanced them for 2 days and then charged and installed in my with a BMS and everthing is working just fine :)
Thank you very much for your feedback. It is great to hear the these videos and information help others to better understand how the cells work, how to set up the battery and make it work for their specific need.
Hab ich doch gesagt. Aktiver Balancer arbeitet hier auch super! Und mal wieder ein schönes Video! Warte schon sehnsüchtig auf den Australien-Sommer!
Kämpfen in unserer Region gerade mit einer Hochwasser Katastrophe.
Stay safe over there! Hoffentlich bist du nicht selbst betroffen.
Ich kann schon etwas mehr Solar sehen, was reinkommt. Die Tage werden wieder etwas laenger und die Sonne steht steiler.
Andy I'm happy that we finally succeed in making you a "believer" 🤣
Btw. the schematics of the balancer are OK - if you have a closer look they are taking the side with the ICs and not the one with the capacitors as their top side.
I'm still a 'tester' 😉
Glad you finally came to your senses. If we live by old technology we'd still be fighting wars with piston aircraft.
Pack voltage is going up because you're putting energy into cells that are deep into the knee, while the energy is coming from cells that are not deeply in the knee.
Yes, that is correct. I missed that.
The bottom "Knee" curve is not linear - the lower the voltage the less energy is needed to proportionally impact the voltage overall voltage increased because your moving energy from a fatter part of the curve where substantial energy is needed to impact on voltage to the thinner more sensitive zone- you are bottom balancing your cells which is probably better for your pack as you have capped the upper voltage at 3.45v preventing it climbing the upper knee much to effectively upper balance accurately
Great vid on using a balancer. It can help squeeze a little bit more out of a pack as it's getting low. A balancer really is cheap piece of mind, plus long-term it might just get more life out of a cell that might have failed sooner. That's a hard thing to test since each cell is unique, but I'd bet it really helps out in the long run. I think a long-term test like 6 months or so and then remove it and check for deviation after a week of no balancer to see if the pre-balancer deviation has returned. That should show if it's doing anything for life extension or not.
That's a great suggestion, thank you.
Aktiv balancer is a must have nice Video. 👍👍👍
Ha, some here say the opposite 😉
@@OffGridGarageAustralia Glaub dehnen nicht, die Lügen 🤣🤣😉
I am an advocate of active balancers. Cheap ones can have issue with proper balancing direction when real world inverter and charger currents causes cell voltages to jump around confusing the balancer. Evaluating performance with no inverter or charging current variance is not real world use case.
Be warned about capacitor charge pump type balancers long term reliabilility with electrolytic caps being subjected to high ripple current. Usually the cap's electrolyte dries out and capacitance declines. Sometimes they burst and short out from the high ripple current. As they are directly connected to cells (through MOSFET switches) there is no safeguard if they short out. If top of caps start to bulge out it is a warning of failures to come.
I know about the problems with capacitors from my electronic background. I think they have used the better quality ones which are fully sealed and don't dry up any more as other types do.
My active balancer is connected parallel to the Daly 200A smart BMS and it works fine since the start. Bms is burning high voltage off and wasted as heat. The active balancer is always on and will continue to balance between full and empty cells. I like it so much that I will do the same next time again. You get more amps in and out of same battery pack.
Thanks for the info. I'm really pleased with the balancer now after several days. It works very well.
So scientific in determining balancer wiring - you had a bunch of caps with negative stripe on them to help trace to the negative terminal.
Voltage increase because voltage is not proportional to charge in lifepo4.
So the battery that were good didn't loose as much voltage as the battery that were charged gained.
Дуже гарний і потрібний огляд.
Дякую тобі, чоловіче!
I really enjoy your very informative videos. Keep up the great work.
Thanks for you feedback and kind words!
I ordered two on the balances for testing, thanks!
Thank you! They work well.
@off-grid-garage Andy, now for a test on overall capacity acheived w/o balancer (until BMS cutoff) Vs. W/cell balancer. In theory you should be able to get more energy out as the higher capacity cells should feed the weaker ones so they all hit cutoff at about same time.
Yep, that's on my list...
Brillant vidéo, very interesting! Was wondering would a balancer work on a 24v lead acid battery with 14 x 2v cells to extend its life? If I understand correctly the balancer only looks at the voltage difference, not the type of battery? Many thanks, keep up the good work!!
Yes a lead acid bank would benefit, and you could avoid or reduce voltage in the adsorbtion phase of charge.
Hi Andy,
With BMS + Active Balancer we are getting more cabling to the battery cells.
I think about using a 16 x WAGO 2002-1781 3-conductor fuse terminal block; for mini-automotive blade-style fuses; with test option; 2.5 mm²; Push-in CAGE CLAMP®; 2,50 mm²;
One wire from each cell to the terminal block. BMS and Balancer connected to the WAGO after the fuse.
Easy disconnect for maintenance reasons by removing the fuses.
Testing with multimeter etc via the WAGO Test pin.
With this structured cabling it would no longer be necessary to touch the cells when doing maintenance, testing etc. and therefore mitigate the risk of shortcuts.
What do you think about this idea ?
I would be worried about resistance across all these additional connections when we measuring in the mV area for balancing.
i use blox FJ5N terminal block with no fuse.
not for maintenance per se but for centralised wiring ease
I see a disadvantage especially in your case with a relay-bms and slightly missmatched cells. If you're battery is at a high state of charge and there is a high amperage outside, overvoltage disconnected will trigger because the balancer destroyed your top balance and will not be able to keep up with the sun. Because you have a relay-bms, there will bee no consistent power anymore until the sun is down and the balancer is finished. You maybe get that alternating on/off situation again...
I don't think this is going to happen. My max charge voltage is only 3.4V and then I let the battery absorb, so current will taper off. So far the 'balancer test' seems to work quite well but I have to wait what happens when I fully charge the battery again.
Thanks for Vid & honest Info. PS; Consider the V increase from early morning to midday due to (Ambient & Chemical) Temperature increase...
Thank you.
Wow Andy! Maybe active balancing is actually the way to go. If the cells can be that far apart with a standard BMS That would almost certainly mean premature degradation and variation to a few cells in the pack over long duration of having different states of charge and discharge.
Yes, I was quite shocked when I saw the BMS in the morning. The pack seemed to be very balanced at the top from my last videos but cell #6 would have cut off early and tripped the BMS at some stage. The active balancer seem to work very well now after a few days.
you have to remember that measuring the current on the balance wires is not a true reading, because with two cells are in series if one is charging and the other next to it is discharging you will get a net current because you are measuring both cells at the same time.
Andy, the total voltage of a battery pack can rise with an active balancer for the following reason.
The voltage of a battery cell is non linear, especially when the battery is near empty or near full.
Let us take an extreme example of a 2S battery pack.
cell 1 : 2,5V
cell 2 : 3,2V
Total = 5,7V
When the active balancer transfers capacity from cell 2 to cell 1, the voltage of cell 2 will decrease less then the increase of voltage of cell 1 due to the non linear behavior of a LiFePo4 battery cell.
after some balancing time one could have following measurments
cell 1 : 2,7V
cell 2 : 3,1V
Total : 5,8V
I hope to have cleared out the origin of a voltage rise when balancing with an active balancer at low SOC or high SOC.
Greetings,
Luc from Belgium (near Austria an far away from Australia)
Thank you. Yeah, that makes sense. Hence it is important to always have a BMS as well which monitors single cell voltages and disconnects the charger/load if one cell gets out of scope.
11:32 ABs does not transfer voltage; it transfers Electric Charge.
Some of your cells had lowered charge capacity resulting in faster to drop when discharging and faster to rise when charging.
You mean current measured as voltage?
From my experience I say that it is better to add some fuses on that balance leads. Nice video !
On your recommendation I got a QUCC BMS. However I got the mosfet one not the relay. On overcharge of a cell this simply turns off the charging, leaving the discharge and balancing functions still working.
You also sold me on the balancer. That works OK, but to stop high cell voltage cut off I run the BMS balancer at 50mV below cut off voltage. This just keeps the balancer out of trouble. Cells are balanced nicely over most of the curve, but getting the top end balanced looks like taking several days. Heading in the right direction slowly.
Keep up the good work....
I wasn't aware that they make smart BMS with fets and higher current (200A).
@@OffGridGarageAustralia Ahh... mine is only 100A
@@OffGridGarageAustralia Is you fuse not 100A ? so 200A BMS is nice but you could get away with a 120A one, and still get 5KVA at the inverter.
On the balancer, have you considered using the other bolt on the busbar so you don't disturb the BMS connections ?
The active balancer is great at both ends of the curve. I would install a switch so I can turn it off once the battery is properly balanced. Then when it starts to drift again turn it back on. Better f you can program it but that adds cost.
Fun times!!!
Are you using a balancer too? Old battery, new battery?
Thanks Andy
No worries
After reading almost all comments here, some concern lower end while other worry upper end.
This is my solution:
Have 2 AB connected (parallel).
The 1st balancer is setup trigger and balance on higher end of voltage. The 2nd balancer handle lower end of voltage.
You only do top balancing, never bottom.
Andy - if you’re cold just put on a sweater. … or give some of your fans the idea to make you an ‘Off Grid Garage’ one 😜😂😂😂
Great idea 👕😃
It is not unreasonable that the voltage went up with the balancer running. Cell 6 was in the steep part of it's charge curve where most of the other cells were in a clatter portion. The balancer will affect the voltage of the higher charged cells much less than cell 6 so cell 6 increases in voltage more than the sum of the higher cells decrease in voltage.
Yes, I figured that later on after reading many comments here about it. It was not obvious when I looked at it at when recording.
I'm curious, could you please do a video of a schematic of how you would set up the system if you were starting again with no limits. Could you have an active balancer beneath a BMS in a 24/7 system on all your batteries.
You can definitely leave the balancer connected in parallel to your BMS. That is no problem.
Just watched more of the balancer videos.
Very odd how you were then getting imbalances caused.
This seems contradictory to the idea of an active balance.
Your videos are very useful, keep up the good work.
Hi Andy, Good day,
Just want to say that I was expecting that you going to change you mind about the active balancer. It is lucky that you got the right one and not the small one which might have change the outcome and your conclusion of this test as well.
Looking forward for the second part of the test at the topo f the voltage and I do expect the almost the same result especially after a few hours after the sunset. it will equalize.
Just probably if you wanna test further on the active balancer , i suggest it would be:
1) The balancer will keep balance the cell even all the cell are balanced.
2) if the above true, that mean the balancer will drain current overtime especially with smaller capacity pack. I had a friend who installed this balancer for the 32650 4S 12V and leave it for few days, the pack drain to 2.++V.
Thank you. So far I'm really please with the result of the balancer. I think the balancer will turn off at a certain stage, either under a certain voltage or if the spread is below a threshold.
Worked on F-4 Phantom avionic systems 1970 - 1974 USAF. Electrics were connected with Amphenol connectors. Looks like to me you could wire up your battery bank with a female multi pin connector and use a male matching connector to connect your BMS. If you wanted to have testing equipment connect to the bank they could be already wired ready to use. Would make it easy to change leads rather than reconnecting terminal rings on each cell every time you wanted to test or rig up something new or different. A strip of banana plugs would also work. Easy to check with a multimeter. Amphenol pins might be close to close together to be checking with multimeter. What do you think?
Well, that could be a solution. What my intension is though, I would like to NOT play around with the big batteries which are in production at some stage and rather have some test cells sitting on the workbench to do testing. Once testing is confirmed I may do these changes to the big batteries.
The final battery won't have anything connected to the terminals any more as the balance leads for BMS and balancer will be connected to the busbar directly (M6 tap).
Oh, I guess I’m standing outside of the wrong garage here. Your sign said FREE WI-FI and I still haven’t figured out the password yet and it’s freezing out here. I thought you said Austria… 🥶
Glad you've caught up to where I was a year ago :-D Welcome! :-)
It's just a test though 😊
@@OffGridGarageAustralia I can feel it coming closer, suddenly no more worries, just a max capacity scenario for your cells that actually partly solves the "more wear on weakest" issue by offloading load to stronger all the time and perhaps long term levelling the performance, too. You know it's good, proven in multiple vids, don't string it out any further, just install them for good and put a disable switch on it for your sanity/fear if you must.
The voltage curve of the battery would actually cause a pack voltage increase.
You are converted. Question is though..... Can I leave the balancer installed permanently?
You can leave it connected permanently and it will work.
Fantastic video, really changed my opinion, thank you!
Thank you Ruben!
Great video, can you leave the balancer permanently on the battery?
Looks like that balancer is doing it's job bottom balancing, but you're not going to like the out of balance situation that it created at the top when the cells are fully charged.
I assume it will be exactly the same at the top now. Everything is balanced 😉
@@OffGridGarageAustralia It will be ok if you stay under 90%, but if you get into the upper end curve, they will be all over the place due to slight differences in the cells.
@@SpeakerKevin Not with the balancer attached, I guess.
@@OffGridGarageAustralia That would be great if the balancer would take care of it, let's keep our fingers crossed.
Thank you
With your raspberry, maybe you could turn on your active balancer with a relay (there is a pad "run" weldded on the active balancer) only when you are in the top or the bottom of your SOC ? It will correct the little deviation every day, but when you're on the flat curve, it doesn't work and don't transfert power between cells.
The balancer runs 24/7 now for the test. If it does not balance in the flat part anyway, why should I make the effort and turning it off? The standby current is only a few mA, far less than for the Pi. Who would give the signal to start the balancer?
@@OffGridGarageAustralia i think you shouldn't balance in top AND bottom... Only one no ? So you should disconnect it ? The rasp know thé soc ? For example if thé soc is under 10%, connect thé balancer ?
@@mccyrille yeah you definitely only do top or bottom balancing.
The Pi knows the SOC but then what? How?
This balancer is impressive indeed. But what does balanced mean? You know, voltage is not everything. So why are some cells too low?
If all cells are equal in terms of capacity, you are right. Balancing the voltage, no matter if at top or bottom, is always good.
If one cell is lower in capacity, you get a problem. At the bottom end, its voltage is too low, so the balancer adds energy to it. Then at the top end, its voltage rises faster, and the added energy appears as an additional imbalancing. The balancer is not capable to align the charging level of the cells to each other. It makes it worse.
If your cells don't have this problem, it will come when cells are getting older. I don't see an automated method to solve this. I would monitor the over- and undervoltage of a weak cell and then decide to add or remove some Ah manually ... until the cell must be replaced. This will come soon, the worst cell gets the highest stress.
The cells are not all the same and never will be. Even they come matched from the supplier, they are not matched. You're dealing with 16 individual cells. And apparently, the drift and spread gets worse when they age over time.
The balancer prevents the battery from being disconnected prematurely by the BMS as cell 6 would have triggered the cell low voltage disconnect. The same happens at the top if #6 goes to high.
OK, very interesting. This makes it a very dynamic system. The missing capacity of the weakest cell is compensated by the balancer by adding energy at the bottom and removing this and more energy at the top. There is no continuous improvement but the weak cell is tossed from one end to the other. You think the balancer is strong enough for this? This is not what you have tested yet.
Hi Andy: At 6:00 it looks to me like the diagram is pictures with the capacitors face down (Notice on the diagram there's no depiction of the capacitors) and you're holding the board with the capacitors face up. This is why the B- and B8 wires are inverted. (Not mirrored as you said, which would be flipped left to right. It's inverted flipped top to bottom)
at 11:20: It's not strange at all that the voltage would rise. You started out with your high cells sitting close to 3.2v. Pulling 1 Ah from a cell at 3.2v won't drop it's voltage very much, but pushing that 1Ah into a cell at 2.8v will cause that cells voltage to rise substantially. So the "sum" of the voltages (IE: pack voltage) is higher.
Yep, thanks. Both of your points are true. Just not obvious for me while recording 🤦♂️😉
SKU make a range of what they call a "capacitor BMS " instead of the more common (and cheaper) bleed balance BMS - it may be the answer to these big cell systems
Working for a week now and it's been great.
Link please
Morning Andy from lockdown 4.0 in Victoria WTF. Now how do you time the vlogs mate? Which video software do you use too? 15 degree how I miss Queensland.
That's in the settings in TH-cam, where you set the publish settings. No additional software needed.
@@OffGridGarageAustralia Thanks Andy, have a great day mate.
Active Balancers balances TWO ADJACENT CELLS by transferring charge from a higher voltage cell into a lower voltage cell. Some ABs have LEDs to indicate which pair it is working on making it a little fun to watch. Current is also depended on the voltage difference. A Balancer might be rated at 5A, but if the voltage difference is small so will the current flow. This is natural; you do not want to overdraw from one cell and overcharge the adjacent only to reverse it the next turn.
I theorize we can use multiple balancers for faster balancing.
ie, using two 9s balancers on a 16s bank. One AB connected to Cells 1~9 and the 2nd AB connected to Cells 8~16.
Hi andy.
I virtually have the same set-up as you.
The main problem i am having is the solar power. When full sun is out i am pumping over 75amps into batteries.
This then raises voltage very fast to and over the 52v , which inturn overloads the batteries and shuts off relay.
This then upsets the victron MultiPlus-II and shuts down, loss of power
52V is far to low. Not sure about your settings but this is only 3.25V/cell. This could mean you're cells are only 30% charged when they reach this voltage. Try to set 55V or 56V in your solar charge controller. That would be 3.45V-3.5V/cell. That should work a lot better.
@@OffGridGarageAustralia thank for your reply andy
I should have explained in better detail.
55.1v is my victron bulk/Absorption charge setting not 52v.
When solar is pumping 75a into batteries voltage increases, on some cells it brings them to 3.6v and then over which triggers the quacc over load as it should as protection, this then cuts power, and MultiPlus-II doesn't like it, gets confused and shuts off inverter to which then has to be manually restarted.... pain
Awesome 😎 your videos rock. Pretty cool testing
Thank you very much!
Good experiment!
Thanks!
Over all voltage is rising because the more charged batteries (in your Situation) are closer the the flatter end for the curve. So if you move 5% soc from most to least charged cell you will have a net increase.
Yes, quite obvious, right? Didn't catch that while recording.
If your inverter is set to stop charging at a certain top voltage and switches of at a certain bottom voltage and the balancer keep your batteries balanced, it makes the bms redundant?
Help me here if Im wrong, the bms does not come near keeping voltages balanced like the balancer. It only helps to stop charging and protect the battery from going to low.
So why do you still need a bms?
You always want a BMS. I show exactly this in the next video. The BMS is your safety net, your insurance for your battery. Never rely on just the charge controller or a balancer. There is always something which can go wrong and without BMS things go 💥 quickly.
You can turn off balancing in your BMS though if you use another balancer.
Your video's are a great resource so thank you. Been following them here in the UK and I have been impressed with the detail.... so thank you for the time and effort you must put into the content creation and all the back office editing you must have to do before releasing them.
Unfortunately when ordering from the AliExpress website there is a minimum spend which they don't tell you what that amount before you can use the discount code. Not sure if this is the same in other countries but here in the UK I have now purchase a 4S and a 16S balancer on separate orders and on both orders I was denied any discount. So, just letting you know it may be helpful if AliExpress actually said what the purchase amount has to be before the discount voucher kicks in.
Many thanks again for the great content.
Thank you very much for your kind comment and feedback.
I read this somewhere here already, the discount code does only seem to work over US$100 spent. Other said it gives you only $2 discount anyway, so probably don't bother about it.
it would be nice to see how the balancer and system do with everything left switched on how it should run just to see how well the system manages itself to imitate several days of really bad weather
Running for 6 days now...😊👍
@@OffGridGarageAustralia yes but havent you been turning the controllers off?
Nice Dog putting out some bird's ❤️
Batrium all the way!!!.... 2 years NO problem.... one install DONE. But only me.
I picked up a couple to play with. They just arrived yesterday. I'm familiar with the boost/buck style and am curious how this capacitor-only style will work. I sure wish I had the 32 channel 'scope I used at a prior job... I'd be monitoring those capacitors!
What do you expect is going to happen with the capacitors?
@@OffGridGarageAustralia I expect they are going to charge to cell voltage or maybe 2x cells, then discharge into the lower cell of the pair. But I'm not sure and I'd like to know how it works!
Well, I ordered one and the promo code comes up that the code is not valid because minimum spend isn’t reached. Total price including shipping was $71.35 so I ordered one anyway since my new 420ah setup is all used cells, so I’ll probably need it. Thankyou for your recommendation
Yeah, I wasn't aware that this code had a threshold in order amount. Stupid... it's only $2 anyway from what others said.
@@OffGridGarageAustralia either way I really appreciate what you’re doing, the ad free content is also delightful. Beers coming your way next time I get paid 👌
Those birds were either yellow-throated miner or noisy miner. Sound like some baby ones around, baby gets looked after by the whole flock who become even more agressive.
Andy, seems like you keep having issues with that BMS maintaining good balancing. I have a 48v, 16s, 90ah Lifepo4 system with a Daly Smart BMS. It is connected to a Growatt SPF LVM 3000w solar all-in-one inverter. The Daly 48v 100ah 16s SMART BMS is exceptional, maintaining balance between all cells usually under 10mv (under light load) and less than 100mv under high load. No need for active balancer. Please consider doing a test with this BMS. It has high and low temp protection too. Good luck and keep up the good work! (And Will is right)
I have to wait until the new battery is in place so I can take the existing one offline and can top balance it properly again (which I never did in the first place).
@@OffGridGarageAustralia Top balancing is a painful, time consuming process, but well worth it in the end…at least it was in my case. I’m looking forward to your progress with the new system as I follow along in your journey. Good luck.
wow so many sections to go into to check this and that they so need one display screen with all the controls like the raspberry pi gui but with more information and control buttons
The balancer itself has no interface, so that's a set a and forget device. Everything else is done through the Victron VRM and the occasional checking of the BMS.
@@OffGridGarageAustralia yeah i think the active bms could be made to trigger with a voltage trigger so the voltages befor you wanted it to balance at you could have it work at
they work even better with higher cell volts (on top). and you can parallel them up also.
Why would you parallel them? For faster balancing?
@@OffGridGarageAustralia if you are running a high current they can keep up better
On the connection diagram, you can see the MOSFETs and other components. So it is definitely the "bottom" side and all pins seems to be right.
The reason for rised voltage is, the flat area in the charge/discharge curve. You need not much energy to charge a cell e.g. from 2.8V to 3.0V (diff=0.2V). The energy comes from cells with 3.2V and this cells will not drop down 0.2V. Maybe only down to 3.15V or 3.10V. So the total voltage will rise. Sometime the losses of the Balancer will decrease the total voltage.
Yep, both is correct, just didn't see that when I was recording. Thanks 😉
Balancing at the bottom AND the top is like pulling on a too short blanket to make it cover you just to put the feet in the cold.
You cannot do both, that's right.
You may be liking your balancer, but its maybe adding 0.25% of capacity at the bottom end. But remember when you were testing it was using more amps than it was using to top up other cells - I suggest you'll be losing the same capacity from balancing as you gain from having a balancer.
However, I think they are worth having but not leave in all the time, but when you do a monthly/quarterly balancing plug it in. That's my plan, mines been in its box for over 6 months now ....
Absolutely, the capacity gains is very little. The only thing it does well is prevent individual cells from running away and trigger the BMS to shut down.
Hi and greetings from Germany,
I have - same as you - never used a balancer so far in my diy 12v LiFePo4 in my camper, no issues so far. But now with my 48v 2P16S battery I am having over/undervoltage issues when charging via solar ( Victron 150/35 ) and someone on FB pointed me in your direction and the use of 48v balancers for ‚bigger‘ batteries. Must have missed that, even I subscribed already long time ago.
I am not sure it will solve my issues, but your test looks promising and I will give it a try.
Can you tell which BMs you are using ? Didn‘t find you mentioned it in the video or description
Thx again for you effort and input 👍
Thanks Uwe. A 16s battery is more likely to go out of balance than a 12V battery. The active balancers work very well and help a lot to bring the battery back in balance. Just ensure, that the balancer is not running all the time. Either use a switch to activate it from time to time when the battery is full or an controller which does that everytime the voltage goes over 54V or so. I have a recent video showing that: th-cam.com/video/kEeD-oM4QnY/w-d-xo.html
Gruesse in die Heimat.
11:40 voltage is rising not because of recovery, but because if you take a Wh out of one of the higher cells the voltage hardly changes, but you put it into a low cell in a the steep part of the curve and the voltage changes dramatically. So the positive and negative changes in different cells are NOT equal because you're moving energy, not current, and not voltage.
Yes, that is correct.
@@OffGridGarageAustralia I know! I only correct you when you make false statements in the vids :-D
@@fredio54 that never happens at all 😂
You’re shunt is on the right place, if you put it before the bms you can’t read your second batteriepack. Now you can just connect your second pack to the shunt in parallel. I got my cells a few months later than you and using a Daly bms it keeps the cells very good balanced.
With more than 1 battery bank, it can only be connected like this. Every bank has its own BMS and shunt measures all banks.
@@OffGridGarageAustralia yep, that’s what i done last week got my second bank with it’s own bms.
Unfortunately the seller on Alibaba.com didn’t deliver the cells properly packed, got them quite much damaged. Don‘t get your cells from Heze Yixin Information Technology Co., Ltd. they promise a lot but don’t keep any off them. Delayed, incomplete and damaged delivery due to bad unprotected packing.
What! Changed your mind my man! Lmao 🤣 Omg can't believe it haha! Cheers buddy 🌞
Hey! I'm still testing...
@@OffGridGarageAustralia lmao! No doubt with out proper testing, no one knows shiztz. Lol cheers buddy!
Voltage can rise when balancing... cause a certain amount of energy in a cell, equivalent to 0.1v could be 0.2v in an other cell which would be at a different SOC...
The problem in that balancer is that you cant define when you activate the balancing. If you have the balancer active in the midle range you will unbalance the state of charge at higher voltages.
incorrect the balancer has a solder point to turn it on and off this can be controlled if left active it will always try to balance when mv range is above what ever it default variation is be it bottom middle or top it will always balance this is the point of them u have a 3s version i use on a solar light setup to keep cells in check as they are salvage and i must say it is doing the job perfect
@@1981dasimpson ah ok. You can set a voltage and it actives on that...
@@MiguelSilva-mb6mb you would need a voltage trigger but you could have the active balancer to turn on at what ever voltage you want with that trigger
@@MiguelSilva-mb6mb as it stands at the moment it checks voltage of cells if they is 10mv difference it wil start to balance 10mv is the one that i have i think each one will trigger at slight different voltage due to imperfections in components but the active do a much better job then passive
The voltage is fixed. I thought it was 30mV to start up the balancer but cannot find this information any more. It's clearly below that.
I have a kinda crazy question... could you use a 16s active balancer with an 8s2p battery for all 16 cells? If it's just balancing cell voltage it should work as a balancer doesn't seem to care about the overall pack voltage right?
No, that will not gonna work and you might cause a short across your cells. The balancer will be damaged as you connect several leads to the same battery. With a 8s2p pack you definitely need a 8S balancer.
You really don't want to balance at low end. Only high end. The smallest cell will reach lowest voltage first. You then put extra charge in only to have it charge full first and have to take it out again. Pick either too or bottom and stick with it. Top I recommend for your use.
Bottom balance won't work for a setup with banks in parallel anyway. But even top balance might be tricky if the balancer of the BMS starts its work. It creates the same imbalance as the active balancer does.
I should top balance and turn off all balancing altogether.
You need more Batterys and aktiv balancer.
Strange hearing you say it’s the first time you use a balancer; don’t you have a JK with an active balancer installed in one of your batteries?
As I watch this video, I'm top balancing my 16S battery at 54.4 volts with a 2A Bluetooth active balancer.
Nice! Top balance at 3.4V only?
@@OffGridGarageAustralia 54.4V float is a little low but this is where I'm starting to see about 4 cells diverge from the rest heading up to 3.5V+ so I'm holding here for a few hours to see if I can get results like you did. The other problem is I have 2 batteries, 1 DIY and 1 YIYEN from China. For some reason the BMS in the China battery is going into high voltage alarm and shut down if I go over 55V. Of course there is no support from China. Eventually I will replace both batteries with a 560Ah DIY project. Was hoping prices of the 280 or 310Ah cells would get down to $75 but so far that only gets you a grade B cell.