Patent ID: 6160382
Filing Date: 2000-12-12
Classification: G01R

Abstract:
A method of determining characteristic parameters of a charge storage device, based on a wide frequency range of impedance measurements and a non-linear equivalent circuit model, which is used to obtain the parameters of the charge storage device such as a primary battery, secondary battery, capacitor, supercapicitor and fuel cell, the method comprising the steps of:(1) measuring voltage and current characteristics in a process of charging/discharging of charge storage device by applying a voltage/current at a predetermined discharge rate;(2) measuring impedance spectra at a predetermined range of frequency by measuring the current and voltage from both terminals of the charge storage device or from an electrical load directly connected to the charge storage device at a plurality of states of charge within the entire charge/discharge interval; and(3) obtaining the parameters of the non-linear equivalent circuit of the charge storage device from the charge or discharge characteristics measured in step (1) and the characteristic impedance spectrum in the predetermined range of frequency measured in step (2).