

i have dissasembled batteries to recharge the 81650 cells inside then reassemble. If they drop below a certain threshhold then the protection circuit won’t charge them. I have a special charger/tester for lithium cells and a battery tab welder. It’s only worth it if the replacement is unavailable and it’s for something very rare.
You’re allowed to buy electricity from a separate broker than your “power company” so they split the bill between power usage and service fees plus there’s state and local taxes.