Complex Impedance Measurements on the Steady State Behaviors of a 10-cell PEFC Stack

Experimental studies on the behavior of a Polymer Electrolyte Fuel Cell (PEFC) stack were conducted by performing complex impedance measurements. Initially, the steady state characteristics of a 10-cell stack were measured, and the power function of the DC current was obtained to represent these characteristics. The frequency properties of the complex impedance apparatus were investigated in order to clarify the limitations of frequency measurement. The components of complex impedance, the real and imaginary parts, were rearranged into two vectors to analyze their frequency responses to power and output DC current.