Today’s cars are computer chips with wheels. Even when parked, there is usually something running in the background. Leave it parked for a week and the battery is run down but will recharge if you drive it for a while. Leave it for three weeks while on travel or because of some dreaded post-op scenario and it won’t start. A battery minder, also called a battery conditioner, is a plug-and-forget device that monitors the battery and trickle charges it as necessary over time to keep it optimally charged. For months!
Car nuts like Jay Leno have these battery minders on every car in their collection. They cost $50 and up plus installation. Most car manufacturers offer a tailored version as an accessory, which will be more expensive but will assure you that it is the right battery minder for your car. You will also need access to an AC outlet in your parking space to plug it in. It might be worth it if you are not driving much anymore or, heaven forfend, thinking about getting rid of your car, because . . .