This is very insightful, thank you. I guess for price per kWh, lead-acid is also still unbeatable. And as you mention, deep cycle can give good lifetime as long

This is very insightful, thank you. I guess for price per kWh, lead-acid is also still unbeatable. And as you mention, deep cycle can give good lifetime as long as you don't go below 40%. I see deep cycle batteries come in all kinds of voltages though - is there a preference? I've seen huge 1000Ah batteries with 4V or 6V.