Lipo unbalanced !?

[pete2222]

What voltage difference is common to see in a 2S Lipo? And how best fix it?

I got my balance charger a few weeks ago and realised one of my Lipos (an FTX voltx 5000MAH) is 3.8V/4.2V.
I have put it through a couple of discharge/balance cycles and it's improving, but not quite balanced yet.

Any advice appreciated. Thanks

[dodgydiy]

i have some 3600's that were like this, cycling brought them back close, but if left for any length of time they drop back away. one was 3.7/4 and took 4 cycles before it would balance within charger time limit, others were less far out

[pete2222]

Originally Posted by dodgydiy

i have some 3600's that were like this, cycling brought them back close, but if left for any length of time they drop back away. one was 3.7/4 and took 4 cycles before it would balance within charger time limit, others were less far out

Thanks for this. Mine are looking much better now after 4 charge/discharge cycles!

[dodgydiy]

was the pack left standing for some time? thats what caused the problem with the ones i have, they were balanced before storage and cells self discharged at different rates

[pete2222]

i bougt these second hand,so could well have been left standing

[Marvin]

It means one of the cells in the pack is weaker than the other one. It is likely to be on its way out.

[neiloliver]

3.8V/4.2V is a huge imbalance. If it does not improve hugely on the balancer you have then try discharging each cell in turn at 2.5A down to 3.0V and then reconnect as a 2S battery put them on a balance charge.

If you soon find that they are out of balance again you have a bad cell.

[pete2222]

Is seems pefectly balanced now and running great. Lets see how long it lasts