Micromachined metallic thin films for the gas diffusion layer of PEFCs

Feasibility and the design parameter effect are examined for micromachined metallic thin film gas diffusion layer (GDL) for polymer electrolyte fuel cells (PEFCs). Titanium thin film is used at present due to its endurance to the cell operation. Cell operation characteristics under various humidification and cell temperature behavior are examined to show the importance of water management. Impact of design parameters such as through-hole diameter, through-hole patterning and the thin film thickness have been investigated to show the parameter dependence as well as the possible high performance with design optimization. The GDL is expected to be used for rigorous modeling of overpotential factors.