Prolusio
Well-Known Member
Another battery tip is do not store batteries fully charged.
I remember seeing the chart below a while ago. Found here! Charge level has a large impact on Li-Ion battery life and performance. If a Li battery is stored @40% charge at a room-ish temperature for a year (25C); you can expect that battery to have 96% of its full capacity remaining.
If you had the same battery in the same conditions, but had charged it to 100% before storing for a year; it might only have 80% potential capacity remaining! That's a big difference.
It could be higher if kept in a cold location (0C), but I suspect like me most people don't have a cold place for battery storage.. Who wants to put batteries in the fridge?
By leaving a battery on the charger it effectively keeps that cell at peak charge while storing, which is the most stressful for a Li-Ion battery.