A composite proton exchange membrane includes first and second outer proton exchange membrane layers each having an exterior peripheral portion. An inner proton exchange membrane layer is interposed between the first and second outer membrane layers. The inner membrane layer has an exterior peripheral portion encompassed within each of the outer membrane layer peripheral portions. A substantially fluid-impermeable edge bonding film is interposed between the first and second outer membrane layers. The edge bonding film circumscribes the inner membrane layer peripheral portion and is disposed within each of the outer membrane layer peripheral portions. The edge bonding film cooperates with the first and second outer membrane layers to encapsulate the inner layer.