ELECTRICITY STORAGE DEVICE AND METHOD FOR CONTROLLING ELECTRICITY STORAGE DEVICE

摘要

A battery pack (10) comprises a plurality of secondary batteries (12) that are connected in series with each other. A connection unit (30) connects an electricity storage unit (20) in parallel to one of the plurality of secondary batteries (12) such that the electricity storage unit (20) has the same orientation with the secondary battery. A voltage measuring unit (40) measures the voltage of each of the plurality of secondary batteries (12). A control unit (50) controls the connection unit (30) on the basis of the measurement result of the voltage measuring unit (40), thereby selecting a secondary battery (12) to which the electricity storage unit (20) is to be connected. When two or more secondary batteries (12) are discharging, the control unit (50) makes the connection unit (30) select a secondary battery (12) that has a relatively low discharge voltage.