Ionic Liquid Composite Polymer Electrolyte Membranes for the Unhumidified Intermediate Temperature Fuel Cell

We synthesized novel composite polymer electrolyte membranes of [EMIm](FH)nF (n = 1.3 and 2.3) ionic liquids and measured their physical and electrochemical properties. The ionic conductivities of composite membrane (P(VdF-co-HFP):s-DFBP-HFDP: [EMIm](FH)2.3F = 1:0.3:1.75 in weight ratio) were up to 11.3 and 34.7 mS cm-1 at 25 and 130{degree sign}C, respectively. We also studied the fuel cell performance using these composite membranes at intermediate temperature without humidification. The OCV observed for the cell using [EMIm](FH)2.3F composite electrolyte was ~1.0 V at 130{degree sign}C and stable during the measurement conducted for over 5 h. The maximum power density of 14.8 mW cm-2 was observed at 37.2 mA cm-2 at 120{degree sign}C. From the high thermal stability and high ionic conductivity, the fluorohydrogenate ionic liquid composite membranes seem to be promising candidate electrolytes for unhumidified PEMFCs at intermediate temperature