In case your battery won't fully charge


My 52V Hydra battery wouldn't fully charge and my 10A charger would just keep cycling on and off indefinitely. I changed the "Single full voltage" parameter in the BMS from 4.15 to 4.2V and now the charge terminates properly.
Whoops... Bad information. The charger cycling on and off at the end of the charge was caused by having the BMS discharge disabled.
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Active Member
I think that 50mV padding is there to increase cell cycle life as well as ensure parallel groups stop charging with a little wiggle room to balance up other groups. Not sure if these BMS's have active balancing or just passive, but if it's just passive then the balancing may only be discharging the groups at 50-150mA

I think the general rule for Liion chemistries is every 150mV below fully charged or above fully discharged you give your cells, it doubles the expected cycle life, given the same charge & discharge rate & operation & temps.

Long term storage (month+) keep the battery 40-50% SOC and stored in a cool dry place. If it's 40F out and dry - your garage is a kinder place to the pack than your cozy 76F living room or den or foyer. Most cell manufacturers state below 15C/59F and above freezing for storage.