DETERIORATION DETERMINATION METHOD AND DEVICE FOR STORAGE BATTERY

摘要

PROBLEM TO BE SOLVED: To determine the deterioration of a storage battery with high accuracy.SOLUTION: The impedance of each frequency is measured by supplying AC current changed in frequency to a storage battery to discharge it. A phase difference curve is created by detecting an impedance phase difference from a measurement value. The deterioration of the storage battery is determined based on a phase difference area determined by the phase difference curve within a predetermined frequency range.