How do you store your rechargeable li-ion batteries safely? In the refrigerator? In a metal box? I’m starting to accumulate quite a few, over a dozen and would like to know a safe way to store them.
A refrigerator is a nice idea. Maybe my rubber strips for model airplanes are too old and I should throw that away and use the space for batteries. I read in some thread that they store best charged to only something like 3.7 V (unplugging my lap top).
Thanks everyone for the ideas. I like the ammo box idea and the small plastic cases. I just don’t want my kids and friends to mess with them, thinking they are just like regular batteries or swipe them and charge them in a conventional charger.
There are theoretical reasons to expect batteries to keep better at cooler temperature, the same way food and rubber bands do, as long as it is not below the working temperature range of the cells.
Just a reminder, some protection circuits tend to have a parasitic draw. It’s a good idea to check protected batteries once a month to make sure voltage hasn’t dropped under 3.7v.
“PowerStream Note: Test data confirms that storage of lithium-ion batteries is best if the cell is partially discharged. In one test by Cadex Electronics ( http://www.buchmann.ca ) after 1 year storage at 25°C the non-recoverable capacity remaining is 96% when stored at 40% initial charge level, but only 80% if stored with 100% initial charge level. This effect is reduced at lower temperature and is a non-issue at 0°C. At higher temperatures the effect is much worse. Cadex’s recommendations are to store below 15° C at 40% of full charge (3.5 volts per cell). Our experience is that with cells stored at room temperature for 3 years that the non-recoverable capacity did not decrease, so this is probably manufacturer dependent.”