To store or not to store

[ePedicab]

I have 3 52V, 20Ah 18650 batteries. A few times a year I need to run all 3 batteries consecutively for 15 hour work days. For most of the year I only need one battery per day. My question concerns the latter scenario.

Is it best to continue cycling the batteries, using a different battery every day? This would keep all 3 of them out of a "storage mode". Or should I use only 1 battery and "store" the other two?

I like the idea of keeping two batteries in storage, thereby only needing to replace the cost of one when it eventually dies.

What is the best way to store them? I heard somewhere, charge them to 80% and store in a cool dry place. Maybe it's better to use them once in a while?

What do you guys think?

[Louis]

Storage levels are typically around 50% and in cool, dry, near refrigerator temps, low 40's are considered by some researchers to be ideal.

[ePedicab]

Full is 58.2 volts, 80% is around 54volts ... So half is like 51 volts?

[spinningmagnets]

If you rotate the batteries once a week, each one of the three would only be resting for two weeks. Even if one of them started experiencing a mystery slow-drain (from a BMS malfunction?), you would likely catch it before there was any damage.

If you keep using them in a rotating schedule (not truly "long term" storage, like half a year over the winter) I would just charge to 80%