2009 Volume 77 Issue 7 Pages 512-516
Water management of the catalyst layer in a polymer electrolyte membrane fuel cell was improved by focusing on the three-phase boundary. To fabricate the cathode catalyst layer, carbon-support with catalyst and fluorine resin were mixed and heat-treated at the melting temperature of fluorine resin. The transmission electron microscopy images of this electrode catalyst showed that the surfaces of the catalyst particle and of the carbon-support were partly coated by thin film of melted fluorine resin. Ionomer electrolyte material was added to this electrode catalyst, and an electrode catalyst with a four-layer structure was fabricated. The durability at 50°C of a single cell using the four-layer electrode catalyst as the cathode was examined. The deterioration rate was lower than that using the conventional three-layer electrode catalyst. In addition, a load change test at 50°C, an OCV test at 50°C, and a durability test at room temperature gave good results.
