Patent ID: 7030618
Filing Date: 2006-04-18
Classification: G01R,H01M,Y02E

Abstract:
1. A method for judging the condition of a secondary battery, characterized in that the method comprises the steps of obtaining a first resistance component mainly composed of an ion conduction resistance of an electrolyte, and a second resistance component mainly composed of a reaction resistance of electrodes respectively by a predetermined method as the internal resistance related value which is related to the internal resistance of the secondary battery, plotting an internal resistance co-ordinate showing a co-ordinate of the internal resistance of the secondary battery in a plane co-ordinate of which one axis component is the first resistance component and the other axis component is the second resistance component, and comparing the internal resistance co-ordinate with a previously obtained relation between the internal resistance co-ordinate and battery condition, which has been previously plotted on the plane co-ordinate, to judge the condition of the secondary battery.