The proton exchange membrane, also called PFSA membrane, is a kind of solid poly electrolyte.The membrane's main character is only allowing the positive ion to go through. Due to this character, the membrane is widely used in PEM fuel cell production, vanadium fuel cell, chlor-alkali, chlor alkali membrane, metal recovery membrane, and also in water electrolysis for producing hydrogen, electrochemical synthesis, gas division, electrochemical sensor and so on. It serves as the solid electrolyte membrane in various kinds of electrochemical cells depending on selective conduction of the cation.The proton exchange membrane has excellent mechanical properties, heat resistance, electrochemical performance and chemical stability. The membrane can work in harsh conditions, such as strong acid, alkali, oxidant media and so on.