I have never needed to charge a starting battery on a boat with proper charging system
and I don't think theres a toy that uses power that I don't have on my boat (LOL) including downriggers, with my kicker at the lowest speed I can go,it keeps it fully charged
I don't have power hydraulic steering .....which can be a killer
and I charge once them in the middle of the winter , only a battery that is put away not fully charged or one that is on it's way out will freeze