waaaa - lipo battery - element voltage is out of balance - delta

[alexus]

Hello World ;-)

I recently bought some new batteries, and despite only using them a few times, I've noticed a voltage difference of over ~0.5 volts. I'm using the ToolkitRC M8S, but the balancing feature doesn't seem to be doing the trick.

Can anyone share any of life hacks for safe, fast and straightforward approach to manage single cells? so one can later use an existing charger to discharge/charge them cautiously, mimicking NiMH battery treatment to achieve a comparable voltage level with other cells.

Thanks in advance!

 

[Jerold]

Everything is within the min/max limits and the charger should do balancing correctly? Is it not balancing correctly?

It could be the charger or the battery. First I would verify the charger is working correctly on another battery. That will eliminate one variable.

Assuming the charger is setup, used correctly and not the problem, the better questions is why are the cells out of whack? The one with the 4.2V might be a problem cell. You can check the Internal resistance (IR) of the all the cells for large deviations as well.

But if these are new packs, you might skip all this and contact the manufacturer and ask them about a warranty claim.

 

[alexus]

Everything is within the min/max limits and the charger should do balancing correctly? Is it not balancing correctly?

it appears so.. when i tried to balancing feature, over time i see higher delta then before.. at least 1 element (2nd) is stuck at ~4.2V and balancing over time brings rest of elements down almost to 0%, while 2nd element still remains fairly high and when i try to charge battery back from 0%, it won't charge as high anymore as 2nd element gets to 4.2V super quick as it's almost there comparing to the rest..

It could be the charger or the battery. First I would verify the charger is working correctly on another battery. That will eliminate one variable.

i have my old battery, which i charged almost to 95% with tiny 83mv delta.. charger is most likely okay and it is new batteries fault(

Assuming the charger is setup, used correctly and not the problem, the better questions is why are the cells out of whack? The one with the 4.2V might be a problem cell. You can check the Internal resistance (IR) of the all the cells for large deviations as well.

why? well, i tell you why))
because i decides to balance them, and as i try to balance them they get more and more out of whack..
while i try to charge, i also see "mR" ~9.99-11.4 2nd element is 10.6, like others (only 5th element is 11.4)

But if these are new packs, you might skip all this and contact the manufacturer and ask them about a warranty claim.

they are new, and i already reached out to seller on ebay where i bought these and seller provided new tracking number (replacement)
how do i check new one? use them once and try to balance them again?))

 

[Jerold]

they are new, and i already reached out to seller on ebay where i bought these and seller provided new tracking number (replacement)
how do i check new one? use them once and try to balance them again?))

In theory you can manipulate each cell through the balance lead as a 1S (single cell) battery. Try to discharge the offending cell down to something in range of the others. But we don't know what's wrong with the cell, which means it's some tedious and time consuming work and if it gets messed up the results can be catastrophic.

If you have replacements coming, I (me personally) would just ditch the bad one. In my mind it's not worth the risk of keeping a potentially bad battery.

while i try to charge, i also see "mR" ~9.99-11.4 2nd element is 10.6, like others (only 5th element is 11.4)

Not sure what "mR" is? But if it's IR relabeled, the numbers are fine. They are reasonable for everyday use and fairly consistent too. i.e. it's not enough that you would see that large voltage difference.

 

[alexus]

In theory you can manipulate each cell through the balance lead as a 1S (single cell) battery. Try to discharge the offending cell down to something in range of the others. But we don't know what's wrong with the cell, which means it's some tedious and time consuming work and if it gets messed up the results can be catastrophic.

yeah, that's what i'm about to do) to convert it to 1s and use lipo 1s and try to do some "magic"))

If you have replacements coming, I (me personally) would just ditch the bad one. In my mind it's not worth the risk of keeping a potentially bad battery.

you may be right here, but will see.. i'm willing to do it once just to try it out, if it'll be too much headache i'll recycle them at local best buy ;-)

Not sure what "mR" is? But if it's IR relabeled, the numbers are fine. They are reasonable for everyday use and fairly consistent too. i.e. it's not enough that you would see that large voltage difference.

i think it's same thing)

 

[Jerold]

Let us know what happens.

 

[alexus]

Let us know what happens.

i've got new batteries (replacement) on Saturday, charged them..
i went to favorite Markham Park on Sunday and used them completely, after 1st charge delta is 52mv and 98mv ('kay, will let you guys know after few charging cycles)

 

[alexus]

and meanwhile i've finally managed to connect through balance port and now charing selected element as 1S
i hope element stays closer to other elements and i don't have to do that again or at least not often, i guess time will tell..
i can totally see why one wouldn't want to do that on long term, as most likely there is an issue with a cell of some kind which can't be addressed easily and at the end of the day battery should be recycle or at very least taken extra maintenance care going forward as safely storing, manually balancing (dis/charging).

 

[Jerold]

Not sure what's happening here? Is it the same cells?

Could just be wonky battery brand too.

 

[alexus]

Not sure what's happening here? Is it the same cells?

using 1s dis/charging, i was able to minimize delta voltage and charge them back to the max!

Could just be wonky battery brand too.

will try to them out later and see the "wonkiness" level)