Impedance changes of the Li-ion cell in the course of discharge

The paper deals with the measurement of the cell impedance parameters during discharging of the Li-ion NCR18650B cell. Re ( Z ) and Im ( Z ) of the battery were measured by PEIS method. The results of the impedance changes during discharging and charging were plot to Nyquist diagrams. The important values namely Rs , Rsei , Rct , Csei , Qsei , Cdl , α , and σ were found during discharging of the Li-ion cell with and without using CPE element.