APPARATUS AND METHOD FOR DIAGNOSING FAILURE OF SWITCH UNIT INCLUDED IN MULTI BATTERY PACK

Disclosed is an apparatus and method for diagnosing a failure of a switch unit included in a multi battery pack. Here, the magnitude of a pack current flowing from each of battery packs connected in parallel to a load is measured, a battery pack whose pack current has a magnitude smaller than the average value by a threshold value or more is identified, and it is determined that an open failure occurs at the switch unit included in the identified battery pack, and the information of the battery pack including the switch unit at which the open failure occurs is output. Preferably, the internal resistance of each battery pack may be statistically analyzed in order to more accurately diagnose the failure at the switch unit. Thus, an open failure of switch units included in battery packs connected in parallel may be easily and reliably diagnosed in a statistical viewpoint.