Highly conductive electrolytes based on poly([HSO3-BVIm][TfO])/[HSO3-BMIm][TfO] mixtures for fuel cell applications

Polymeric ionic liquids have been attracting increasing interest as proton exchange membranes for anhydrous fuel cell applications. In this work, novel and designed composite membranes based on the polymeric ionic liquid matrix poly([HSO3-BVIm][TfO]) and its analogue non-polymerizable ionic liquid [HSO3-BMIm][TfO] are developed for H2/O2 proton exchange membrane fuel cells working without external humidification. The chemical affinity between the ionic liquid monomer and the ionic liquid results in stable, flexible and transparent polymeric membranes. The effect of temperature and the quantity of non-polymerizable ionic liquid on the ionic conductivity and fuel cell performance are analyzed. Fuel cell tests and ionic conductivity experiments show the great potential of these ionic liquid-based polymers as proton exchange membranes.