Solar / LiFePo4 batteries and the Cold.

[GeraldTheBonzai]

Currently trying to work out how best to insulate my batteries.
My solar rig feeds into a 280Ah LiFePo4 battery. The BMS in this specific battery (EcoWorthy) will still charge when at around -2C. The battery is outside in the shed and for the first time this season, last night it got down to around 1C outside.

Now I only charge the battery, obviously, in the day when sunny, at which point the temperature in the shed is normally above 0C (at the moment). However am think about the scenario where we might have an extended cold snap and I need to charge the battery but its below 0C. I can't have something like a diesel heater in the shed - got stuff in there that wouldnt play nicely with it. So options are either to insulate the battery to reduce heat loss, or build a heating pad (which is a strong contender - I have the bits I need).

So people with solar rigs. What are you doing to ensure that you can charge your batteries if the temperature drops below freezing?