Resistance calculation device, resistance calculation method, and program

Abstract

A resistance calculation device includes: a characteristic calculation portion configured to calculate a shrinkage rate for each single electrode based on a capacity shift amount of a positive electrode of a deteriorated secondary battery, a capacity shift amount of a negative electrode of the deteriorated secondary battery, a deterioration amount of the positive electrode, and a deterioration amount of the negative electrode, and to calculate a curve representing characteristics of a state of charge and an open circuit voltage of an equivalent circuit of the deteriorated secondary battery by deforming an opening end potential curve for each single electrode before deterioration of the deteriorated secondary battery by the shrinkage rate for each single electrode based on a fixed point; a change amount calculation portion configured to calculate an amount of change in the open circuit voltage of the equivalent circuit based on a difference between the opening end potential curve for each single electrode before the deterioration and the curve representing the characteristics of the state of charge and the open circuit voltage of the equivalent circuit; and a resistance calculation portion configured to calculate a DC resistance of the equivalent circuit by dividing a result of addition of an amount of change in a DC voltage of the equivalent circuit to which a pulse current is applied and the amount of change in the open circuit voltage of the equivalent circuit by a current value when the pulse current is applied to the equivalent circuit.