EFFECTS OF DIFFUSION LAYER POROSITY OF THE ELECTRODES FOR PEMFCS ON THE ELECTROCHEMICAL BEHAVIOR OF ELECTRODE AND THE CELL PERFORMANCE CHARACTERISTICS

摘要

1. In this study, the effects of gas diffusion layer porosity of the electrodes for polymer electrolyte membrane fuel cells operated with H_2/O_2 on the electrode characteristics and cell performance have been investigated. Results of cell performance and ac impedance analysis were explained in terms of mass transfer limitation of reactant gas due to the difference of porosity of gas diffusion layer. 2. Best performance of electrode, a current density 517 mA/cm~2 at 0.7 V cell voltage and maximum power density, 0.52 W/cm~2 at 0.5 V was obtained by using pore forming treatment for gas diffusion layer and hot coating method for catalyst layer. 3. Hot coating method allowed us to exclude the using of PTFE and glycerin in catalyst layer without fissured electrode surface and collapse of catalyst layer during operation.