A battery equalization system, comprising: a collection circuit , configured to collect parameter information of cells in a battery pack ; an equalization circuit , configured to perform equalization processing on the cells in the battery pack ; a controller , connected to the collection circuit and the equalization circuit separately, and configured to: when it is determined, according to the parameter information of the cells in the battery pack , that a cell in the battery pack needs enabling of equalization, control the equalization circuit to perform equalization processing on the cell that needs enabling of equalization; 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,, wherein the power supply branch circuit comprises a first power supply branch circuit and a second power supply branch circuit ; the first power supply branch circuit is connectable to the power supply unit and connected to the battery equalization system, and the first power supply branch circuit is configured to supply power to the battery equalization system and loads of the entire vehicle except the battery equalization system; the second power supply branch circuit is connectable to the power supply unit and connected to the battery equalization system, and the second power supply branch circuit is configured to supply power to the battery equalization system; and when the vehicle is in the OFF gear , meaning when the battery pack stops discharging or charging, and a cell needs enabling of equalization, the second power supply branch circuit is in a connected state, and the first power supply branch circuit is in a disconnected state under the control of a vehicle body controller . a collection circuit , configured to collect parameter information of cells in a battery pack ; an equalization circuit , configured to perform equalization processing on the cells in the battery pack ; a controller , connected to the collection circuit and the equalization circuit separately, and configured to: when it is determined, according to the parameter information of the cells in the battery pack , that a cell in the battery pack needs enabling of equalization, control the equalization circuit to perform equalization processing on the cell that needs enabling of equalization; 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,, wherein the power supply branch circuit comprises a first power supply branch circuit and a second power supply branch circuit ; the first power supply branch circuit is connectable to the power supply unit and connected to the battery equalization system, and the first power supply branch circuit is configured to supply power to the battery equalization system and loads of the entire vehicle except the battery equalization system; the second power supply branch circuit is connectable to the power supply unit and connected to the battery equalization system, and the second power supply branch circuit is configured to supply power to the battery equalization system; and when the vehicle is in the OFF gear , meaning when the battery pack stops discharging or charging, and a cell needs enabling of equalization, the second power supply branch circuit is in a connected state, and the first power supply branch circuit is in a disconnected state under the control of a vehicle body controller . <EOS>