Investigation of in-situ test protocols for accelerated aging of gas diffusion media of PEM fuel cells

Abstract

In the present work, in-situ accelerated degradation of GDL was investigated using a commercial single cell under different test conditions, based on high potential, mechanical stress and local excess temperature stressors. For each stressor ASTs of approximately 328, 241 and 245 h were performed, respectively. Throughout a test the MEA configuration was changed, with the introduction of a fresh CCM and a fresh cathode GDL to isolate the effect of the cathode GDL. In-situ measurement techniques used to characterize the impact on MEA degradation, include polarization curves, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). To closely examine the cause of degradation roots, CCM samples before and after aging were analyzed by scanning electron microscopy (SEM).