The battery I’m entertaining is a used Tesla model S pack... 1 of 8 or so used in the car. They come from wrecked low mileage cars 24v, > 5Kwh. I’ll start with 1 and may add another in parallel later. I’m shooting for 800-1000 watts of solar. The link I mentioned above uses a heating blanket if needed to warm the battery from solar if needed. I know I’ll need battery management - there are aftermarket bms’s for these packs.
Weight is a concern - this pack weighs 55 lbs, vs 6 gc’s weighing 450lbs? And 300ah? @ 12v (50%) (3600wh) vs 4000wh (80%)