POWER STORAGE DEVICE AND CONTROL METHOD THEREOF

PROBLEM TO BE SOLVED: To make an inter-terminal voltage between batteries uniform and to perform large current discharge.SOLUTION: A power storage device includes: a plurality of batteries connected in series between a first terminal and a second terminal; a plurality of capacitors connected in series between the first terminal and the second terminal; a plurality of first switches connected between respective nodes of batteries closer to the first terminal and nodes of corresponding capacitors closer to the second terminal; second switches connected between respective nodes of batteries closer to the second terminal and nodes of corresponding capacitors closer to the second terminal; a third switch connected between the first terminal and a node closer to the first terminal of the capacitor closest to the first terminal among the capacitors; and a control part by which, when discharging the batteries with a first current, the first switches, the second switches and the third switch are alternately turned on and off, when discharging the batteries with a second current larger than the first current, the first switches are turned off and the second switch closest to the second terminal among the second switches and the third switch are turned on. 【課題】電池間の端子間電圧を均一化し、かつ大電流放電を可能とすること。【解決手段】第１端子と第２端子との間に直列に接続された複数の電池と、第１端子と第２端子との間に直列に接続された複数のキャパシタと、電池の第１端子側のノードと対応するキャパシタの第２端子側のノードとの間に接続された複数の第１スイッチと、電池の第２端子側のノードと対応するキャパシタの第２端子側のノードとの間に接続された第２スイッチと、第１端子とキャパシタのうち最も第１端子側のキャパシタの第１端子側のノードとの間に接続された第３スイッチと、電池を第１電流で放電するときに第１スイッチと第２スイッチおよび第３スイッチとを交互にオンおよびオフし、かつ電池を第１電流より大きい第２電流で放電するときに第１スイッチをオフし第２スイッチのうち最も第２端子側の第２スイッチと第３スイッチをオンする制御部と、を具備する蓄電装置。【選択図】図１