Why not keep them in the house while you are at home, but under a smoke detector. And on a hard floor on a metal sheet, with a bucket of cold water handy, if you really want to be correct.Woosh state that batteries shouldn't be stored indoors which is very sensible for the folk in the south but my outbuildings all get down to below minus 10 each winter so I've no choice but to keep them in my porch. They stay in the shed from around May to around October. View attachment 34431
It can 'stand' being out in sub zero temperatures, but the available power will be reduced when the battery is cold. So you can safely leave it out in the cold (and that should actually extend its life as it degrades slower) but you should bring it indoors to warm up for a few hours before using it.Having just had a battery re balanced, I was advised not to leave the battery in the garage in the cold.
However, e-cars are left out in all weathers, so what is the answer.
Can a lithium battery stand freezing?
Only some. For example, Nissan Leaf e-cars used to have a battery heater, turning on at -16 degrees C and turning off at -10 degrees C.I'm told that if you plug an electric car in to charge when the temperature is too low, it will delay the actual charge until the heating elements around the batteries have raised them up to a safe temp.
Can you actually buy them?One answer to keep batteries warm & cosy in freezing conditions is look on online /ebay / amazon for RHU heater units (and lead lined shorts) - good ones produce heat continuously for several decades...
Each Lwrhu capsule produces 1 watt of heat. The LWRHU units are mechanically attached singly and in groups so as to maintain the temperature of critical electonics and batteries.