A battery equalization system, a vehicle, a battery equalization method, and a storage medium. The battery equalization system includes: a collection circuit; and equalization circuit; a controller, connected to the collection circuit and the equalization circuit; and a power supply branch circuit, controlled by the controller to get connected to a power supply unit and the battery equalization system when a vehicle is in an OFF gear and a cell needs enabling of equalization, so that the power supply unit supplies power to the battery equalization system.