This guy has a different take.My understanding is that they will last longer with less often charge cycling. Good theory, but it bit me in the butt yesterday. My running battery went flat, because I've hardly run the motor (third trip out this season, on small water). The 3-bank charger isn't set up ATM to just maintain the house battery. I'll go back to plugging in every trip again, and eat whatever longevity downgrade.