Abstract
Gas diffusion layers (GDLs) coated with a hydrophobic microporous layer (MPL) have been commonly used to improve the performance of polymer electrolyte fuel cells (PEFCs). In the present study, a hydrophilic and hydrophobic triple MPL coated GDL, in which a thin hydrophilic layer was coated on the hydrophobic double MPL, was developed to achieve further enhancement of the PEFC performance under high humidity conditions. The oxygen transport resistance was determined from the limiting current density values of polarization curves to evaluate the ability of the GDL to prevent flooding. A triple MPL coated GDL, in which the polytetrafluoroethylene (PTFE) content in the hydrophobic MPL in contact with the hydrophilic layer is 20 mass% and that in the MPL in contact with the carbon paper substrate is 10 mass%, exhibits much lower oxygen transport resistance than a conventional hydrophobic MPL coated GDL.