High Performance Anion-Exchange Membranes and Ionomers for Use in Alkaline Membrane Fuel Cells

Abstract

This presentation will describe the latest research at the University of Surrey on the development of high-performance anion-exchange membranes (AEM) and ionomers (AEI) for use in alkaline membrane fuel cells (AEMFC). These anion-exchange polymer electrolyte matreials are produced using the peroxidation pre-irradiation grafting method (RG). Recent achievements that will be discussed in this presentation include: Synthesis of RG-AEMs with new chemistries that are more stable to alkali than those containing the benzyltrimethylammonium benchmark;The ability to produce RG-AEMs based on low density polyethylene (LDPE) as well as poly(ethylene-co-tetrafluoroethylene) (ETFE);Synthesis of thinner AEMs (< 30 μm thickness);Synthesis of an interesting class of RG-based solid-state AEI powders;AEMs with high hydroxide conductivities and high performances in hydrogen-fuelled AEMFC;Advanced use of Raman micro-spectroscopy for studying radiation-grafted anion-exchange polymer electrolytes. We will demonstrate that changes in head-group chemistry can switch off several alkali degradation mechanisms for RG-AEMs. We will also show that 2 W cm-2 peak power densities can be achieved in H2/O2 AEMFCs containing Pt cathodes and > 1 W cm-2 can be achieved with non-platinum-group-metal cathodes. The figure below shows the performance of a thin ETFE-based RG-AEM in H2/O2 and H2/air(CO2-free) AEMFCs when Ag/C cathode is used as a cathode electrocatalyst. Figure 1