Storage Voltage - Lithium Ion Polymer Battery - 3.7v 100mAh,

[richcdev]

I just bought a small batch of the Lithium Ion Polymer Batteries, 3.7v 100mAh and 150mAh, and an Adafruit micro LiPo charger to learn about and use them in small projects.

My question is about "storage voltage" and tiny LiPos.

1) When these LiPos are fully charged they are at about 4.2 volts. Can I store them like that for any length of time?
2) Should I discharge them to 3.8v, storage voltage?
3) What is the best way to store these tiny batteries for periods of days or weeks?
4) What is a good way to easily drain them to storage voltage?
5) Are these tiny batteries sensitive to charge, discharge, storage just the same as big, multi-cell, high mAh Lipos?

Thanks,
Richard

[adafruit_support_bill]

There is a lot of conflicting on the subject of storage. It is hard to separate fact from the superstition. RC hobbiests generally work with high capacity packs with high discharge rate specifications and no protection circuits. The risks involved with these packs are substantial.

It is definitely bad to store LiPos discharged. The natural process of self-discharge can lead to an over-discharged cell. LiPo cells come from the factory with a partial charge to avoid that condition. They are not shipped with a full charge. This partly has to do with safety. The more energy that you store in the battery, the more energy that could be released if the battery were subject to extreme temperatures or physical trauma during storage or transport.

I store my small cells charged. I also keep my cell phone and other LiPo powered devices charged. Keep you cells in a dry location, free from temperature extremes. And protect them from physical abuse that could dent or puncture the skin of the cell.

[adafruit_support_mike]

80% charge is often used as a rule of thumb.

That's about where most LiPo chargers switch from constant-current mode to constant-voltage mode.