Internal impedance detection device, internal impedance detection method, degree of deterioration detecting device and the degree of deterioration detection method

摘要

An internal impedance detector for detecting the internal impedance of a secondary cell with high accuracy. A computing section (106) divides the variation of each voltage detected by a voltage variation detecting section (103) by the variation of the current detected by a current variation detecting section (105) for the same detecting time as that for the voltage variations to compute the internal impedances. A judging section (107) checks the variations of the internal impedances computed by the computing section (106) and judges from the check result whether or not the internal impedances have reliability. Only when the judging section (107) judges that the internal impedances have reliability, a generating section (109) generates output internal impedance according to the internal impedances.