STORAGE BATTERY DIAGNOSTIC SYSTEM

PROBLEM TO BE SOLVED: To provide an energy-saving, reliable storage battery diagnostic system which can properly detect the capacity of each storage battery of a battery pack comprising a plurality of storage batteries connected in series while reducing power consumption. SOLUTION: The storage battery diagnostic system 10 comprises an impedance measuring section 32 for measuring the internal impedance of each storage battery constituting the battery pack, a discharging section 24 for discharging a sample storage battery until its voltage drops to a predetermined voltage with a constant current, and a control section 13 which detects the product of the time elapsed until the voltage of the sample storage battery has dropped to the predetermined voltage through the discharge with the constant current and the constant current value during the discharge as the capacity of the sample storage battery and estimates the capacity of remaining storage batteries except the sample storage battery in accordance with the internal impedance measured by the impedance measuring means and the detected capacity. COPYRIGHT: (C)2007,JPO&INPIT