Lead-acid wants to be stored full and topped up, because sitting discharged damages it; lithium chemistries are generally stored part-charged and cool. The maker’s manual gives the figure for that pack, and the figures genuinely differ between chemistries.
Most batteries that die early are not worn out by use. They are left somewhere.
Why lead-acid is stored full
A discharged lead-acid battery sulphates, and prolonged sulphation is not reversible by ordinary charging. Storage means full, in the cold if possible, with a periodic top-up or a maintenance charger that supplies one automatically.
Why lithium is stored differently
Lithium chemistries age faster when held at a very high state of charge, particularly when warm. The usual advice from makers is a partial charge and a cool place — and the exact figure belongs to the pack, because the management system inside it has its own thresholds.
The cold question
Charging a lithium battery below freezing is the failure mode that does permanent damage, and packs increasingly refuse it outright or include a heater for that reason. Discharging in the cold generally reduces capacity temporarily without harming the pack, which is a different situation entirely.
What a season off looks like
Disconnect so nothing is quietly drawing. Note the state of charge. Store where the temperature is stable rather than merely low. Check once during the season rather than in spring, because a pack drifting towards its cut-off is recoverable while it is still above it.
What people ask before they order
Does a battery lose charge just sitting there?
Yes, at a rate that depends on chemistry and temperature. A battery management system also draws a small standing current, so a lithium pack left for months can drift lower than expected.
Can a deeply discharged pack be recovered?
Sometimes, and sometimes not — many battery management systems refuse to accept charge below a threshold, deliberately. Whether a particular pack has a recovery procedure is stated by its maker.
Last reviewed 16 September 2026