Cell balancing method, cell balancing device, and energy storage system including the cell balancing device

摘要

A method of balancing a plurality of battery cells includes acquiring an open circuit voltage (OCV) of a battery cell of the plurality of battery cells connected in series; determining a state of charge (SOC) of the battery cell based on the OCV of the battery cell; determining a differential value in the OCV of the battery cell per a change of the SOC of the battery cell, in accordance with the SOC of the battery cell; and activating cell balancing of the plurality of battery cells when the differential value is greater than a reference value.