Post-mortem analysis of high-frequency current ripples effects on HT-PEMFC aging

Power converters in proton exchange membrane fuel cell systems operating at high temperature (160 °C) generate high-frequency current ripples, raising concerns about their impact on the degradation of membrane electrode assembly (MEA) materials. In a previous study, a 2600-h aging test was performed on two cells: one operated under constant current density (0.2 A cm −2 ) and the other subjected to high-frequency (20 kHz) triangular current ripples of 20 % peak-to-peak amplitude. Herein, a post-mortem analysis is carried out on two aged MEAs, with and without high-frequency current ripples, in comparison to a fresh MEA. Various characterization techniques provided new information about the gas inlet/outlet regions and the degradation phenomena observed in certain components. The results suggest that the catalyst is the only component significantly affected by aging, and high-frequency current ripples appear to have no real impact on materials degradation. • Two HT-PEMFC cells ran 2600 h at 0.2 A/cm 2 with a 20 kHz, 20 % peak-to-peak triangular current ripple. • Structural, morphological, and chemical analyses were done on all MEA layers, focusing on gas inlet and outlet sides. • Post-mortem analyses reveal that only the catalyst layer undergoes significant aging. • No difference in material degradation is observed with or without high-frequency current ripples.