not for a boat but on one of my motorcycles i put an antigravity lithium-ion battery and when it senses a constant drain like over winter it shuts off. in the spring there is a button switch you depress and resets and you have a charged battery.
I have a 48volt golf cart that takes 8 6 volt batteries, that is a $2,000 bill every 5-6 years.
Would this new lithium ordeal fix this sonofabitching expense?