Battery storage

[Nightshard]

I intend to store some batteries to a few months.
should i empty them to 3.2 or fill them to 4.2?

 

[Rader2146]

You should store them at 40-60%, or 3.6-3.8V.

If you store them too low, they can self-discharge to under there minimum voltage and might not re-charge. Store them too high and it stresses the battery, shortening it's life.

 

[Nibiru2012]

From Battery University:

Simple Guidelines for Storing batteries

Primary batteries store well. Alkaline and primary lithium batteries can be stored for 10 years with moderate loss capacity.

Remove battery from the equipment and store in a dry and cool place.

Avoid freezing. Batteries freeze more easily if in discharged state.

Charge lead acid before storing and monitor the voltage or specific gravity frequently; apply a boost if below 2.10V/cell or an SG below 1.225.

Nickel-based batteries can be stored for five years and longer, even at zero voltage; prime before use.

Lithium-ion must be stored in a charged state, ideally 40 percent. This assures that the battery will not drop below 2.50V/cell with self-discharge and fall asleep.

Discard Li-ion if the voltage has stayed below 2.00/V/cell for more than a week.

How to Store Batteries