BATTERY DIAGNOSTIC DEVICE AND METHOD

A method for diagnosing a battery according to one aspect of the present disclosure includes a differential profile generating step of generating a differential profile representing a relationship between a differential capacity, which is obtained by differentiating a capacity of a battery with respect to a voltage of the battery, and the voltage, for each predetermined diagnosis cycle; a target peak detecting step of detecting a target peak in which a differential capacity value decreases and then increases or a voltage value increases and then decreases as a usage time of the battery increases, among peaks of the differential profile; a peak information obtaining step of obtaining target peak information including the differential capacity value and the voltage value of the target peak from each of the plurality of differential profiles generated while the diagnosis cycle is repeated multiple times; and a diagnosing step of diagnosing a state of the battery based on the target peak information obtained from the plurality of differential profiles.