Spare battery storage?

[Dog George]

How would you store your spare battery fully charged or empty?

 

[anotherkiwi]

At 80% or about 3.65 V per cell.

 

[flecc]

Definitely never empty since the cells can drain further into failure.

At least 40% since most batteries BMS continue to use tiny amounts of current all the time. For that reason its important to recharge for an hour or two at least every three months and preferably once every one to two months to keep the cells in good condition.
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