According to one embodiment, a method for making a battery value evaluation index, includes applying a predetermined charge/discharge pattern to a predetermined battery, detecting a largest SOC value and a smallest SOC value of the predetermined battery, and setting a width between the largest SOC value and the smallest SOC value as “A”, detecting a charge limit SOC value at which the predetermined battery shows the highest SOC value, detecting a discharge limit SOC value at which the predetermined battery shows the lowest SOC value, and setting a width between the charge limit SOC value and the discharge limit SOC value as “B”, and determining that a life of the predetermined battery has ended in the predetermined charge/discharge pattern when a state of B>A has changed into a state of B≧A.