Electrochemical impedance spectroscopy (EIS) is a nondestructive
technique and could provide time-dependent information
about the characteristics of the dynamics of the processes.
It is a diagnostic tool that has been used to investigate complex
non-linear processes, i.e., electrochemical systems such as
electrolytic cells and battery. The frequency dependence of the
impedance of an electrochemical process is measured via EIS by
applying a sinusoidal AC potential (or current) to the cell and by
analyzing the current (or potential) response [23]. EIS has already
become a primary tool for research on PEM fuel cells, including
analyzing performance losses in various processes in fuel cells. The
applications of EIS in PEM fuel cells are mainly focused on the
modeling of the electrochemical process with equivalent circuit
(EC) [24] and identifying the contributions of various processes to
the total resistance, such as charge transfer and mass transport