POWER STORAGE SYSTEM

To provide a power storage system capable of accurately grasping a full charge capacity of a battery pack.SOLUTION: A power storage system that performs charging and discharging with an external system includes a power converter, a plurality of battery packs connected in parallel with each other to the power converter, and a control device that controls an operation of the power converter. The control device operates the power converter to supply power from a designated first battery pack of the plurality of battery packs to a designated at least one second battery pack of the plurality of battery packs to completely discharge the first battery pack. The control device operates the power converter so as to supply power from the at least one second battery pack to the first battery pack to fully charge the first battery pack. The control device calculates a full charge capacity of the first battery pack based on a transition from a fully discharged state to a fully charged state.SELECTED DRAWING: Figure 3 【課題】組電池の満充電容量を精度よく把握する。【解決手段】外部システムとの間で充放電を行う蓄電は、電力変換装置と、電力変換装置に互いに並列接続された複数の組電池と、電力変換装置の動作を制御する制御装置とを備える。制御装置は、複数の組電池のうちの指定された第１の組電池から複数の組電池のうちの指定された少なくとも１つの第２の組電池に電力を供給するように電力変換装置を動作させて、第１の組電池を完全放電する。制御装置は、少なくとも１つの第２の組電池から第１の組電池に電力を供給するように電力変換装置を動作させて、第１の組電池を満充電する。制御装置は、完全放電の状態から満充電の状態への遷移に基づき、第１の組電池の満充電容量を算出する。【選択図】図３