Contact resistance between gas diffusion layer and catalyst layer of PEM fuel cell

In this study, the electrical contact resistance between gas diffusion layer (GDL) and catalyst layer (CL) on an electrolyte membrane was experimentally evaluated as a function of compression. The contact resistances between the GDL and CL decreased nonlinearly as the GDL thickness decreased due to the compression pressure. The values of the contact resistance between the GDL and CL were found to be more than one order of magnitude larger than the contact resistance between the GDL and graphite, and even comparable to the ionic resistance of the membrane. Because of the large value and variation in contact resistance between the GDL and CL, severe current distribution may be created inside the cell. The results reported here should be highly useful in providing a more accurate picture of the transport phenomena in a fuel cell. (C) 2007 Elsevier B.V. All rights reserved.