An electrolyte membrane assembly for use in a fuel cell or other electrochemical device includes an ion exchange membrane, a base electrolyte reservoir configured and operable to maintain a volume of a basic electrolyte solution in contact with at least some of the first face of the membrane, and an acid electrolyte reservoir configured and operable to maintain a volume of an acidic electrolyte in contact with at least a portion of the second face of the membrane. The membrane may be a cation exchange membrane or an anion exchange membrane. Also disclosed are fuel cells which incorporate the electrolyte membrane assembly.