BATTERY VOLTAGE EQUALIZATION APPARATUS

A battery voltage equalization device 1 for an automotive battery Bm formed from a plurality of batteries B connected in series includes: a voltage measurement unit 2 that measures respective battery voltages of the batteries B; a current measurement unit 4 that measures a charge-discharge current I of the automotive battery Bm; a cell balancing unit 7 that equalizes the respective battery voltages of the batteries B; and a control unit 8 that performs a voltage equalization control through the cell balancing unit 7 on the basis of the battery voltages measured by the voltage measurement unit 2, wherein the control unit 8 starts the voltage equalization control on the condition that the voltage equalization control is determined to be necessary on the basis of the respective battery voltages and that a discharge current Id of the automotive battery Bm measured by the current measurement unit 4 is determined to be stable.