I do not want to be anxious about battery fire in any way. So I will store and charge batteries in my shed in a box made of ciment boards.
So the worst can happen is smoke in my shed.
But in the winter the shed is not heated. It can get to -35 celcius here. I am thinking about adding a little heater and a thermostat in the box that I will insulate.
But before I want to ask if that is necessary and what is the best temperature for battery storage. I will not charge or use batteries during the winter but I want to keep them in good shape.
My batteries are Samsung 30q cells organized in a pack over deck, and I will get lipos or molicells in the future.
You’re probably okay with an occasional dip to -35°C but it’s certainly not recommended. Definitely let them come up to room temp before charging or use!
Just based on my personal experience with how storage temp affects cell aging. Colder than 0°C didn’t seem to make any difference in extending cell life.
0°C is also the coldest temp you want to charge a Li-ion cell at so never storing them at below 0°C means you never have to worry about charging them whenever you want.
Anything related to batteries, you just listen to @Battery_Mooch , he is a legend on many communities, I knew him from vaping and now from e-skate, he is the guru.
Thanks Master for all your work and wisdom!
Not sure there is someone in the world with as much testing as you do, but there is definitely no one that gives as much time and dedication to help others (at least in that area of expertise) , I really mean it, Thank you
That 0°C number is just my preference for a couple of reasons. There’s nothing that makes it the best.
As we saw, according to the datasheet the 30Q is rated down to -30°C for storage. I can only say that storing at -20°C is within the specs. I can’t guarantee that it won’t cause any issues for you.
But I guess that is true no matter what temperature we store cells at.
Be sure to store them in something air-tight to prevent condensation but it must be something that opens easily to release pressure in case a cell fails! Do not use some type of sturdy box that will become a pipe bomb if gets pressurized. Perhaps something like doubled zip lock food storage bags?
Bring each cell down to about 3.4V - 3.6V or so, the exact value is not important. You just want them about 1/3-1/2 charged to reduce risks and help reduce the internal chemical activity that ages the cell while it’s sitting in storage.
