Abstract: A storage battery device includes a battery unit, a first circuit breaker, a second circuit breaker, and a control unit. The first circuit breaker switches between connecting and disconnecting a first-electrode side of the battery unit and an external device. The second circuit breaker switches between connecting and disconnecting a second-electrode side of the battery unit and the external device. The control unit supplies power to the first circuit breaker and the second circuit breaker in sequence with the power supplied to the second circuit breaker offset relative to the power supplied to the first circuit breaker by a time period equal to or longer than a time difference required for a sum of currents flowing through the first circuit breaker and the second circuit breaker to reach an upper bound current that is set as an upper bound of a current.