The low-temperature Direct Propane Polymer Electrolyte Membrane Fuel Cell (DPFC) based on low-cost modified membranes was demonstrated for the first time. The propane is fed into the fuel cell directly without the need for reforming. A PBI membrane doped with acid and a Nafion 117 membrane modified or non-modified with silicotungstic acid were used as the polymer membranes. The anode was based on Pt, Pt-Ru or Pt/CrO3 electro catalysts and the cathode was based on a Pt electro catalyst. For non-optimized fuel cells based on H2SO4 doped PBI membranes and Pt/CrO3 anode, the open circuit potential was 1.0 Volt and the current density at 0.40 Volt was 118 mA.cm-2 at 95°C. For fuel cells based on Nafion 117 membranes modified with silicotungstic acid and on Pt/CrO3, the open-circuit voltage was 0.98 Volt and the current density at 0.40 Volt was 108 mA.cm-2 while fuel cells based on non-modified Nafion 117 membranes exhibited an open-circuit voltage of 0.8 Volt and the current density at 0.40 Volt was 42 mA.cm-2. It was also shown that propane fuel cells using anodes based on Pt-Ru/C anode (42 mW.cm-2) exhibit a similar maximum power density to that exhibited by fuel cells based on Pt-CrO3/C-anode (46 mW.cm-2), while DPFC using a Pt/C-based anode exhibited lower maximum power density (18 mW.cm-2) than fuel cells based on the Pt-CrO3/C anode (46 mW.cm-2).
Assessing the degradation pattern and mechanism of membranes in polymer electrolyte membrane fuel cells using open-circuit voltage hold and humidity cycle test protocols
