Polymer electrolyte membranes for high‐temperature fuel cells based on aromatic polyethers bearing pyridine units

Abstract

This review is focused on the design and synthesis of new high‐temperature polymer electrolytes based on aromatic polyethers bearing polar pyridine moieties in the main chain. Such materials are designed to be used in polymer electrolyte fuel cells operating at temperatures higher than 100 °C. New monomers and polymers have been synthesized and characterized within this field in respect of their suitability for this specific application. Copolymers with optimized structures in order to combine excellent film‐forming properties with high mechanical, thermal and oxidative stability and controlled acid uptake have been synthesized which, after doping with phosphoric acid, result in ionically conducting membranes. Such materials have been studied in respect of their conductivity under various conditions and used for the construction of membrane‐electrode assemblies (MEAs) which are used for fuel cells operating at temperatures up to 180 °C. New and improved, in terms of oxidative stability and mechanical properties in the doped state, polymeric membranes have been synthesized and used effectively for MEA construction and single‐cell testing. Copyright © 2009 Society of Chemical Industry

Novel concept of polymer electrolyte membranes for high-temperature fuel cells based on ETFE grafted with neutral acrylic monomers

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Exceptional durability enhancement of PA/PBI based polymer electrolyte membrane fuel cells for high temperature operation at 200 °C

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Preparation and Characterisation of Proton Exchange Membranes Based on Crosslinked Polybenzimidazole and Phosphoric Acid

“…On the basis of this method, the so-called Fenton test is widely used for the stability evaluation of PEMFC membranes [40,41]. By immersing the membrane to a 3% hydrogen peroxide solution containing 4 ppm Fe 2+ at 80°C, the phenomenon of flocculation is observed, and the flocculation time of each membrane is recorded and listed in Table 2.…”