battery bank for weekend use yurt in western maine?

[Jafo]

If you keep your batteries charged at 100%, then even the coldest temps should not bother them. The mistake I see people make is they go to their weekend cabin, run the batteries down to 50% and then leave. The batteries at this point will now freeze at a much higher temperature. Once they freeze, they're done.

I have learned this from experience which is why I have a small generator (think Harbor Freight 2 stroke, $80 generator) and a 24v marine battery charger for when I visit my yurt in the winter. When I wake up on the morning of my last day there, unless I am expecting full sun (which charges my bank in about 45 minutes), I will run the generator & charge the batteries until I am ready to leave.