Patent attributes
The electric power storage device of an electric power storage system includes plural electric power storage bodies and a switching relay. The switching relay is capable of being switched between a first state where the plural electric power storage bodies are connected in series, and a second state where the plural electric power storage bodies are connected in parallel. The switching relay allows each of the plural electric power storage bodies to be electrically disconnected from the rest of the electric power storage bodies. The control unit controls the switching relay into the all-off state where the plural electric power storage bodies are electrically disconnected from each other, when the main relay is in an opened state.