POWER STORAGE DEVICE

PROBLEM TO BE SOLVED: To provide a power storage device capable of charging a cell almost over-discharged even when a power-storage module is supplying a load with an electric power.SOLUTION: A power storage device comprises: a power-storage module 10 having a plurality of cells 11 to 17 capable of being charged and discharged, which are connected in series, and discharging as a power source for a load 18; a plurality of voltage detector units 11a to 17a each serving to detect a voltage Vc between terminals of the corresponding cell 11 to 17; an input/output insulation type current limiter 19 of which the input side is connected to the power-storage module 10, and the output side is connected so as to be able to charge the cells 11 to 17; and a controller 20 which determines, based on detection signals from the voltage detector units 11a to 17a, of the cells 11 to 17, the cell which has lowered to a determination voltage Vca as a first must-charge cell RC1, and causes the input/output insulation type current limiter 19 to charge the first must-charge cell RC1 while the power-storage module 10 is discharging.SELECTED DRAWING: Figure 1 【課題】蓄電モジュールが負荷に電力供給している間にも、過放電間近となったセルを充電することができる蓄電デバイスを提供することを目的とする。【解決手段】充電及び放電可能な複数のセル１１〜１７を直列接続して構成され、負荷１８の電源として放電する蓄電モジュール１０と、各セル１１〜１７の端子間電圧Ｖｃを検出する電圧検出部１１ａ〜１７ａと、蓄電モジュール１０に入力側が接続され、出力側が各セル１１〜１７を充電可能に接続された入出力絶縁型電流制限装置１９と、電圧検出部１１ａ〜１７ａの検出信号に基づいて各セル１１〜１７のうち判定電圧Ｖｃａに低下したセルを第一要充電セルＲＣ１として判別し、蓄電モジュール１０の放電中に、第一要充電セルＲＣ１の充電が入出力絶縁型電流制限装置１９を介して行わせる制御装置２０と、を備える。【選択図】図１