Abstract
For efficient use of Pt catalyst in polymer electrolyte membrane fuel cells, the effects of cathode catalyst layer (CL) structure on the cell performance were evaluated by experiments and model analysis for various I/C ratios. To distinguish oxygen transport resistance in the CL from other resistances, IV characteristics were measured with different total pressures, and the limiting current density method was applied. Pore size distributions of the CLs were measured by nitrogen physisorption method, and the CL structural parameters were estimated using the estimation model developed by the authors. Using the model analysis of oxygen transport resistances in CL with the estimated parameters, the contributions of various oxygen transport resistances in CL were evaluated in further detail, and we discuss the relationship between the oxygen transport resistances and the cathode CL structure.