BATTERY DIAGNOSIS DEVICE AND METHOD

A battery diagnosis apparatus according to an embodiment disclosed herein includes an interface unit configured to obtain after-charging state of charge (SOC) in every charging cycle, for each of a plurality of battery cells and one or more processors configured to calculate a charging amount-to-average of each of the plurality of battery cells, based on the after-charging SOC, calculate a change degree of the charging amount-to-average of each of the plurality of battery cells with respect to a charging cycle, calculate an indicator by applying a cycle-specific weight value to a change degree of a charging amount-to-average of a diagnosis target battery cell among the plurality of battery cells, and diagnose abnormality of the diagnosis target battery cell based on cycle-specific indicators of the diagnosis target battery cell.