Replacement AoLithium 12V 100Ah Battery Showing Cell Imbalance

[Matteo]

Hi everyone,


AoLithium sent me a replacement 12V 100Ah lithium battery to substitute a previous faulty unit. The battery is in parallel with two others of the same model and capacity, which have been working fine.
However, this replacement battery is showing a significant cell imbalance, while the other two remain perfectly balanced. I reached out to AoLithium support, but I haven’t received any response yet.

Does anyone have suggestions on how to bring the cells back into balance—preferably without opening the battery or accessing individual cells?

Any help or insight would be much appreciated!

Thanks!

 

[wpns]

Looks like it is not balancing, I would take it out of the parallel circuit and use a separate bench supply to get the voltage up to where it is balancing, but not so high that it trips out on cell overvoltage. And let it balance until it’s back in line.

 

[Matteo]

Looks like it is not balancing, I would take it out of the parallel circuit and use a separate bench supply to get the voltage up to where it is balancing, but not so high that it trips out on cell overvoltage. And let it balance until it’s back in line.

Thank you! Any suggestion on voltage settings?

 

[wpns]

Thank you! Any suggestion on voltage settings?

SWAG 14V, but work your way up to 14.5 slowly. BMS disconnects will be the indication that you have gotten too aggressive

 

[mikefitz]

Any suggestion on voltage settings?

13.8 volts or even lower if the cell volts reach protection level. Balance may only occur when a cell is over 3.40 or 3.45 and the battery is charging.
Can you see and change perameters with the App?

Hold the battery in a high state of charge at the low voltage for severa hours. If you don't see any protection events, increase the voltage slightly and repeat. No need to use a charge voltage higher than 14.2 volts.