Patent attributes
A battery system controller is provided which is used for a battery system including a generator, electrical loads, a lead storage battery, a high performance storage battery which has higher-power and higher-energy density, and an opening and closing switch which switches the generator and the lead storage battery, and the high performance storage battery to an electrically conducting state or an interrupted state, a terminal voltage of the high performance storage battery being controlled so as to be lower than a terminal voltage of the lead storage battery. The battery system controller includes a control unit which allows the opening and closing switch to switch from an electrically conducting state to an interrupted state on the condition that charging current flowing to the high performance storage battery is smaller than a determination value, the larger an internal resistance of the lead storage battery, the smaller the determination value is set.
