Power storage system

A power storage system, comprising:

• a first battery including a first power storage, a second power storage, and a first switch unit configured to switch between a first voltage state in which the first power storage and the second power storage are connected in series and chargeable at a first voltage, and a second voltage state in which the first power storage and the second power storage are connected in parallel and chargeable at a second voltage;
• a three-phase motor including coils of three phases connected at a neutral point, the three-phase motor being configured to be driven by electric power supplied from the first battery;
• an inverter connected on an electric power transmission path between the first battery and the three-phase motor;
• a DC power supply circuit connected to a first connection portion positioned on an electric power transmission path between the inverter and the first battery;
• a branch circuit branched from the DC power supply circuit on a positive electrode side of the DC power supply circuit, and connected to a coil of any one phase among the coils of three phases;
• a capacitor having one end and an other end, the one end being connected to an electric power supply circuit, which connects the inverter and the first battery, at a negative electrode side, and the other end being connected to the branch circuit or the electric power supply circuit at a positive electrode side;
• a pre-charge circuit connected, between the inverter and the first connection portion of the DC power supply circuit, to an electric power transmission path between the inverter and the first battery;
• a converter connected to the pre-charge circuit;
• and
• a second battery connected to the converter and having a voltage lower than the first voltage and the second voltage.