Internal hydration H2/O2 100 cm2 polymer electrolyte membrane fuel cell

This work deals with a new arrangement of a polymer electrolyte membrane fuel cell (PEMFC) support which allows the operation of a 100 cm2 surface area fuel cell with cold and unhumidified gases. Hydrogen is not recycled. Both gases (pure hydrogen and oxygen) are heated and humidified internally, each one crossing a porous carbon block. This allows a simplified water management. Classical low platinum loading E-Tek® electrodes, hot-pressed on Nafion® 117 and 112 membranes, are used. Performances are then a little higher than those of comparable PEMFCs in the literature: 0.7 V at 0.7 A/cm2 for Nafion® 117, and 0.724 V at 1 A/cm2 for Nafion® 112, under 4/6 bar (absolute) of H2/O2 at 100 °C. The values of PEMFC resistance obtained in fitting the data were found to be R = 0.254 (with Nafion® 117) and 0.108 Ω cm2 (with Nafion® 112). The membrane contribution to the cell resistance was then estimated to be Rm = 0.204 and 0.058 Ω cm2, respectively (with Nafion® conductivity estimated at 0.103 S/cm at 100 °C in working fuel cell conditions). This membrane is therefore the major contributor to the total cell resistance.