Battery Apparatus and Current Sensor Diagnosis Method

A battery apparatus, including a plurality of battery packs including a first battery pack and a second battery pack connected in parallel, a plurality of current sensors including a first current sensor measuring a current of a first battery pack, a second current sensor measuring a current of the second battery pack, and a processing circuitry diagnosing the first current sensor and the second current sensor based on a first ratio between a current of the first battery pack and a current of the second battery pack that are calculated based on resistances or capacities of the plurality of battery packs, and a second ratio between the current of the first battery pack and the current of the second battery pack that are measured by the plurality of current sensors.