automobiles have regulators that limit voltage to some precise amount. usually about 15v, enough to push charge into the battery.

marine apps use pretty big inverters. 4000W continuous, with 7500W surge are available for money. although there are some pretty big batteries on a boat using these things, at high power levels, the battery is not really "seen" by the system. big boats have big appliances in the kitchen, and have more than a kitchen sink. a deep freeze for 15 people for 15 days has some size to it.