Patent ID: 8058835

Claim:
A controller for a rechargeable battery mounted on a vehicle using an engine as a power source, the vehicle including a starter motor for starting the engine and a vehicle controller for controlling the starter motor by repeatedly stopping and starting discharge of the rechargeable battery when an index indicating a charged state of the rechargeable battery satisfies a discharge suspension condition, the controller comprising: a control unit that when operated: instructs the vehicle controller to stop discharging the rechargeable battery when the index indicating the charged state of the rechargeable battery satisfies the discharge suspension condition, and temporarily moderates the discharge suspension condition to suppress repeatedly stopping and starting discharge of the rechargeable battery when the rechargeable battery is expected to supply power to the starter motor, wherein the control unit instructs the vehicle controller to stop discharging the rechargeable battery when the index indicating the charged state of the rechargeable battery satisfies the moderated discharge suspension condition when the rechargeable battery is expected to supply power to the starter motor.