Composite perfluorinate membranes

Abstract As typical composite perfluorinated membranes applied to proton exchange membrane fuel cells, two types of membranes with different reinforcements are reviewed, focusing on their preparation methods, mechanical and electrochemical properties. One is Gore‐select ® which is reinforced with a porous polytetrafluoroethylene (PTFE) sheet. The thin membrane is prepared by impregnating a solution of perfluorinated ionomer into a thin PTFE porous sheet. The other is PTFE micro‐fibril reinforced membrane. The thin membrane is prepared by stretching a thicker composite film. Compared with non‐reinforced membranes, the composite membranes have many advantages both in mechanical properties and in electrochemical performance.