Abstract: A method of calculating an available capacity includes the steps of: calculating a first estimated SOC from a value in voltage; calculating an integral of a value of a current and adding the integral to calculate a second estimated SOC; calculating a difference between the first and second estimated SOCs; calculating a first correction coefficient R(1) from the value in voltage; calculating a second correction coefficient R(2) to be smaller for the current having a smaller value; and adding the second estimated SOC to an correction term, or the dSOC multiplied by R(1) and R(2), to calculate a corrected SOC.

Abstract: A method of calculating an available capacity includes the steps of: calculating a first estimated SOC from a value in voltage; calculating an integral of a value of a current and adding the integral to calculate a second estimated SOC; calculating a difference between the first and second estimated SOCs; calculating a first correction coefficient R(1) from the value in voltage; calculating a second correction coefficient R(2) to be smaller for the current having a smaller value; and adding the second estimated SOC to an correction term, or the dSOC multiplied by R(1) and R(2), to calculate a corrected SOC