Mechanical Damage Propagation in Polymer Electrolyte Membrane Fuel Cells due to Hygrothermal Fatigue

Temperature and relative humidity cycles play an important role in the initiation and propagation of mechanical damage in the PEM fuel cell membrane electrode assembly (MEA). However, there have been few studies on the mechanical damage evolution in PEM fuel cells due to humidity and temperature variations. In this study, we investigate the damage propagation in the MEA, with a special focus on the membrane/CL interface. A finite element model based on cohesive zone theory is developed to describe the effect of relative humidity (RH) amplitude on mechanical damage propagation in the MEA. Results showed that having larger RH variation in the applied cycles can result in up to 3.4 times higher fatigue stresses at the interface, and hence a considerably faster rate for delamination propagation.