Experimental study on carbon corrosion of the gas diffusion layer in polymer electrolyte membrane fuel cells

Generally, the GDL of a PEM fuel cell experiences three external attacks: dissolution of water, erosion of gas flow, and corrosion of electric potential. Of these degradation factors, this study focuses on the carbon corrosion of electric potential and investigates its impact through the accelerated carbon corrosion test. This study confirms that carbon corrosion occurs at the GDL, which decreases the operating fuel cell’s performance. To discover the effects of carbon corrosion, the GDL property changes are measured through various devices, including a scanning electron microscopy, a thermo gravimetric analyzer, and a tensile stress test. Carbon corrosion causes not only loss of weight and thickness but also degradation of mechanical strength in the GDL. In addition, the GDL shows serious damage in its center.

► In PEM fuel cells, carbon corrosion occurs in the gas diffusion layer (GDL).
► Both thickness and weight of the GDL decreases after the carbon corrosion test.
► Carbon corrosion mainly occurs in the center of the GDL.
► Corrosion of center layer was an outcome of structural weakness, and this lowered the mechanical strength of the GDL.
► Structural damages and losses because of corrosion affect the fuel cell performance as well.