Cross-linker effect in ETFE-Based radiation-grafted proton-conducting membranesudI. Properties and fuel cell performance characteristics

摘要

Cross-linking of styrene grafted and sulfonated fuel cell membranes is essential to obtain well-performing and durable membranes.udIn this study, the properties and fuel cell performance of radiation grafted membranes based on poly(ethylene-althexafluoropropylene)(ETFE) 25 micron with different extent of cross-linking, using divinylbenzene (DVB )monomer toudstyrene, were investigated. The water uptake and proton conductivity decrease as a function of increasing the extent of crosslinking.udAlso, the membranes become more brittle. Fuel cell performance is limited by the high ohmic resistance of the membraneudat high degrees of cross-linking, whereas at low degrees of cross-linking the membrane–electrode interface is of poor quality.udOptimum performance is obtained at an extent of cross-linking corresponding to a styrene:DVB monomer ratio v/v of 95:5 in theudgrafting solution.