Bears repeating. Can’t say this enough.
Do not let any battery go dead.
Lead acid or any lithium battery. There is nothing that damages batteries more except leaving it dead for days.
Do not leave DQ or most chargers plugged in. If switch is on, Gem is draining battery. That’s just the way they are. Dq chargers do not restart in most cases, nor can they charge a dead battery.
I have seen many schemes posted, but all are destined to kill batteries. Simply turn off the switch and a fully charged battery will be ok for months.
If it doesn’t last, battery is on the way out, having a high self discharge.
In the case of lithium, shut down bms to prevent one cell from pulling them all down through run-away balancing.
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