Degradation decision manner of accumulator, degradation decision device and power source system of accumulator

摘要

PPROBLEM TO BE SOLVED: To solve a problem wherein deterioration by an abrupt change or sudden change is not taken into consideration in the prior art, and a problem wherein a device or the like capable of determining the deterioration of a secondary battery is required because the secondary battery is not brought sometimes into a desired voltage or capacity, even an obtained internal impedance is within a prescribed range, in a method of measuring the internal impedance of the secondary battery. PSOLUTION: The present invention provides a method and a device for determining the deterioration of the secondary battery by discharging, self-discharging or discharging forcibly the secondary battery for an optional time of standing, to measure a discharge voltage therein, and for determining the deterioration by a level and a ratio of the voltage, or by comparing and/or computing a characteristic of the secondary battery with that of nondefective one, and provides an electric power source system therefor. PCOPYRIGHT: (C)2007,JPO&INPIT