Power supply control apparatus and battery unit

A battery unit that is applied to a power supply system that includes a first storage battery and a second storage battery as a voltage source, the battery unit comprising:

• a first output terminal to which the first storage battery is connected;
• a second output terminal to which at least either of an electrical load that is driven by electric power supply from the voltage source and a power generator is connected;
• the second storage battery;
• a first opening and closing unit that is provided on a first electrical path that connects the first output terminal and the second output terminal, and opens or closes the first electrical path;
• a second opening and closing unit that is provided on a second electrical path that connects a connection point on a side further towards the second output terminal than the first opening and closing unit on the first electrical path and the second storage battery, and opens or closes the second electrical path;
• and
• a control apparatus that controls opening and closing of the first opening and closing unit and the second opening and closing unit, wherein
• the first opening and closing unit and the second opening and closing unit have a plurality of switches that are connected in series and a plurality of diodes that are respectively connected in parallel to the plurality of switches, in which the plurality of diodes include diodes that are arranged in opposite directions to each other, and
• the control apparatus includes a determining unit that determines that an abnormal state has occurred in which a current is flowing to any of the plurality of diodes in a state in which the plurality of switches are turned off, and a control unit that controls the switch that is connected in parallel to the diode through which the current is flowing to an on-state, when the abnormal state is determined to have occurred.