I'm thinking of replacing my Kohler 5E with a 12V Lithium 400-600 AHr bank and a Victron Multiplus inverter/charger. I only use my 120V when I overnight to heat water (15-30 minutes/ day), coffee maker/microwave (10-20 min/day) and/or hot plate (10-20 min / day). With that load, I figure a 400...