What is the shelf life of a Lithium Ion battery?

[Dr. Tweedbucket]

... even if you keep it charged up, keep it cool, like in a refridge and don't use em?

Also, is it better to store them charged up to 3.7V or store them with store with more of a medium charge?

 

[alpg88]

... even if you keep it charged up, keep it cool, like in a refridge and don't use em?

Also, is it better to store them charged up to 3.7V or store them with store with more of a medium charge?

store then at 20-40% charge. storing it fully charged kills capacity.

i still have cells from 10 years ago working, however i had some relatively new cells die.

 

[InvisibleFrodo]

I never charge to 4.2 volts anymore. I set my charger to switch from constant current to constant voltage at 4.1 volts. Doesn't sound like much, but it makes a huge difference to cycle life. Also helps to reduce the voltage stress of spending time at or near fully charged.

 

[Nichia!]

I never charge to 4.2 volts anymore. I set my charger to switch from constant current to constant voltage at 4.1 volts. Doesn't sound like much, but it makes a huge difference to cycle life. Also helps to reduce the voltage stress of spending time at or near fully charged.

How do you know that?

 

[WalkIntoTheLight]

Store at 3.7v resting voltage, dry, and in the refrigerator. That will give you the longest shelf life. You should get well over 10 years, if it's a name-brand quality cell. You might lose 5%-10% capacity after 10 years. More important, is the internal resistance will go up. That might turn it from a high-drain cell into a moderate-drain cell. I don't really know what to expect with internal resistance, other than it will go up some.

I have old laptop cells that are over 10 years old, and they've lost less than 20% of their capacity, at a low drain rate (250mA). They were never well cared for, and spent most of their time at full charge, so consider them worst-case. But they're good Samsung cells. I still use them in lights, though try to limit the drain to less than 1A.

 

[lumen aeternum]

Is there a charger with a switch to "charge to 3.7v for storage" vs "full voltage for use?"

 

[archimedes]

Some chargers have an IFR chemistry setting which is pretty close.

 

[Bazsy]

Is there a charger with a switch to "charge to 3.7v for storage" vs "full voltage for use?"

The SkyRC MC3000 has storage mode and charges/discharges to get there.