BATTERY SYSTEM DIAGNOSING APPARATUS AND METHOD

Disclosed is a battery diagnosing technology capable of effectively diagnosing a defective battery cell among a plurality of battery cells included in a battery system at an early stage. The battery system diagnosing apparatus diagnoses a battery system including a plurality of battery cells having electrode tabs therein, and includes a voltage measuring unit configured to measure an end voltage at every charging or discharging for each of the plurality of battery cells; and a processor configured to accumulate the end voltage of each battery cell measured by the voltage measuring unit over time and detect a battery cell having a defect in the electrode tab among the plurality of battery cells based on the accumulated end voltage trend.