Chapter 4 - Physics-based impedance spectroscopy characterization of operating PEM fuel cells

Abstract

Polymer electrolyte membrane fuel cell impedance models based on transient mass and charge conservation equations are developed. The models are fitted to experimental impedance spectra of the segmented high- and low-Pt cells operating in the range of current densities between 0.1 and 1.0A cm−2. The functional cell layers' fitting oxygen and proton transport parameters are discussed. We show how the models help to identify the peaks in the distribution of relaxation times spectra.