Manufacturing process for membrane-electrode assemblies

A process of manufacturing membrane-electrode assemblies, said process comprising

• forming an electrolyte membrane by (a) producing a wet electrolyte membrane film by a film casting method in which a solution of a proton conductive polymer in a first organic solvent is flow cast on a film-casting substrate, and (b) reducing an amount of residual solvent in the wet electrolyte membrane film to form the electrolyte membrane;
• applying a second solvent to at least one facing surface of an electrode substrate and the electrolyte membrane;
• and
• then pressure bonding said electrolyte membrane with said electrode substrate to form a membrane-electrode assembly.

A process of manufacturing membrane-electrode assemblies, said process comprising

• forming an electrolyte membrane by (a) producing a wet electrolyte membrane film by a film casting method in which a solution of a proton conductive polymer in a first organic solvent is flow cast on a film-casting substrate, (b) reducing an amount of residual solvent in the wet electrolyte membrane film by soaking in water, and (c) drying the soaked, wet electrolyte membrane film to form the electrolyte membrane;
• applying a second solvent to at least one facing surface of an electrode substrate and the electrolyte membrane;
• and
• then pressure bonding said electrolyte membrane with said electrode substrate to form a membrane-electrode assembly.