Proton Exchange Membrane Fuel Cell Working at Elevated Temperature with Ionic Liquid as Electrolyte

Ionic liquid (IL) of 1-ethyl-3-methylimidazolium hydrogen sulfate ([Emim]HSO4) free of halide was prepared. The IL was absorbed on a piece of porous asbestos film and used as the electrolyte to fabricate a fuel cell, which was tested in the temperatures ranging from 30 to 168 °C. A maximum power density of 0.6 mW.cm-2 was obtained at 168 °C. The conductivity of the composite IL membrane was measured at various temperatures and the increasing conductivity with temperature was observed. The results indicate that it is promising to apply ionic liquid as the electrolyte for PEMFC to work at elevated temperature, especially at temperature higher than 145 °C, which is critical to wave off problems related to the poisoning of trace amount of CO in the reformed hydrogen from methanol or methane.