| abstract |
A battery diagnostic device includes a sensing unit configured to measure a current and voltage of a battery, and a processor configured to estimate a SOC of the battery based on the measured current, select a plurality of SOCs from SOC-voltage data mapping the voltage and the estimated SOC with each other, divide a preset SOC region into a plurality of sub-regions based on sizes of the selected SOCs, calculate a region change value of each of the sub-regions based on the sizes of the sub-regions and a size of a preset reference region, diagnose whether at least one of an active material area, a depth of discharge and a depth of charge of the battery changes based on the calculated change values of sub-regions, and determine whether a mode of the battery is a normal mode or a failure mode based on the diagnosis. |