Abstract: An electrolyte is provided having a backbone that includes a plurality of aromatic constituents coupled together by at least one atom having a &pgr;-cloud, and in which a halogen atom and an ion exchange group are covalently bound directly to the backbone. Furthermore, the electrolyte is high temperature resistant and may comprise perhalogenated polymers, including perhalogenated polyphenylenes, perhalogenated polyamides, perhalogenated aromatic polyesters, perhalogenated polyimide, etc. Still further, the electrolyte may have acidic groups as ion exchange groups, including sulfonic acid groups, or phosphoric acid groups.