US Patent 10279761 Vehicle power-supply device

A first power supply line and a second power supply line are connected to a load device. A power-supply control device supplies power of a first electrical storage device to the load device via the first power supply line. The power-supply control device supplies power of a second electrical storage device to the load device via the second power supply line. A fuse and a relay of the power-supply control device constitute a first current path between the first electrical storage device and the load device. A fuse and a relay of the power-supply control device constitute a second current path between the second electrical storage device and the load device. A control circuit detects the direction of current on the first current path and the second current path, and detects whether there is a short-circuit between the first power supply line and the second power supply line.