Patent ID: 9366728
Filing Date: 2016-06-14
CPC Classification: G01R

Claim Text:
1. A degradation measurement device comprising: a battery sensing section that measures a voltage across a secondary battery; a current sensing section that measures a current flowing through said secondary battery; and a control section that holds in advance the value of an external impedance present in a discharge path outside said secondary battery, discharges said secondary battery from a first measurement time to a second measurement time at which an integrated discharge capacity based on a discharge current measured by said current sensing section becomes equal to a predetermined discharge capacity reference value, calculates an internal impedance present in said secondary battery at said second measurement time based on the voltage measured by said battery sensing section, calculates a second open voltage at said second measurement time by multiplying the sum of said external impedance and said internal impedance by the discharge current measured by said current sensing section, and calculates a recovered capacity of said secondary battery based on a first open voltage at said first measurement time, said second open voltage and said discharge capacity reference value.