Experimental study of the effect of dissolution on the gas diffusion layer in polymer electrolyte membrane fuel cells

• Published in: International journal of hydrogen energy Vol. 36; no. 19; pp. 12427 - 12435
• Main Authors: Ha, Taehun, Cho, Junhyun, Park, Jaeman, Min, Kyoungdoug, Kim, Han-Sang, Lee, Eunsook, Jyoung, Jy-Young
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-09-2011; Elsevier
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Degradation; Dissolution; Durability; Electrolytes; Energy; Exact sciences and technology; Fuel cells; Fuels; Gas diffusion; Gas diffusion layer; Hydrogen; Hydrophobicity; Membranes; Polymer electrolyte membrane fuel cell; Polytetrafluoroethylenes; Degradation; Durability; Polymer electrolyte membrane fuel cell; Gas diffusion layer; Measurement; Scanning electron microscopy; Gaseous diffusion; Polymer electrolytes; Hydrogen; Ethylene; Experimental study; Dissolution; Carbon paper; Membrane; Performance; Fuel cell
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2011.06.096

The gas diffusion layer (GDL) is important for maintaining the performance of polymer electrolyte membrane (PEM) fuel cells, as its main function is to provide the cells with a path for fuel and water. In this study, the mechanical degradation process of the GDL was investigated using a leaching test to observe the effect of water dissolution. The amount of GDL degradation was measured using various methods, such as static contact angle measurements and scanning electron microscopy. After 2000 h of testing, the GDL showed structural damage and a loss of hydrophobicity. The carbon-paper-type GDL showed weaker characteristics than the carbon-felt-type GDL after dissolution because of the structural differences, and the fuel cell performance of the leached GDL showed a greater voltage drop than that of the fresh GDL. Contrary to what is generally believed, the hydrophobicity loss of GDL was not caused by the decomposition of polytetrafluoroethylene (PTFE).
► Hydrophobicity of GDL decreases after a water dissolution test (leaching test). ► GDL degradation by water dissolution reaches a steady state. ► Structure of GDL affects the degradation extent. ► PTFE parts of GDL are not damaged by water dissolution. ► Damaged GDLs by water dissolution affect fuel cell performance.