INFLUENCE OF ELECTRODIC PROPERTIES ON WATER MANAGEMENT IN A SOLID POLYMER ELECTROLYTE FUEL-CELL

The water transport in a solid polymer electrolyte fuel cell (SPEFC) can be regulated by varying the amount of hydrophobic agent (polyfluoroethylenepropylene) in the gas diffusion layer of the anode, which controls the ionic resistance as well as the gas diffusion in the cell. It has been found that at high water transport the ionic resistance of the electrolyte is lower, while gas diffusion is hindered by the presence of a high water content. A maximum in the cell performance is obtained at intermediate water transport, when the ionic resistance is reasonably low and the mass transport phenomena become negligible. Prototech electrodes, which are morphologically different from ours, also showed a low ionic resistance at low water transport.