Method, program and apparatus for detecting internal information of a rechargeable battery and apparatus including said detecting apparatus

A detecting method for detecting internal information of an inspective rechargeable battery when said inspective rechargeable battery is charged by a constant current-constant voltage charging regime, comprising at least a step (A) of measuring an elapse of time (t) from the time when a constant current charging mode at a constant current value I0 is shifted to a constant voltage charging mode at a constant voltage Vmax and measuring a charge current value I in the constant voltage charging mode, a step (B) of obtaining a period of time from said shift time to the constant voltage charging in the constant voltage charging mode until the time when said charge current value I0 in the constant voltage charging mode reaches a given current value IM, and a step (C) of obtaining an electricity quantity charged in the constant voltage charging mode with respect to the inspective rechargeable battery.