BigPatents India

An electrochemical fuel cell (110) comprises an anode electrocatalyst layer (120), a cathode electrocatalyst layer (121), a polymer electrolyte membrane (114) interposed between the anode and cathode electrocatalyst layers, an anode flow field plate (122), a cathode flow field plate (124), an anode fluid distribution layer (130) interposed between the anode flow field plate (122) and the anode electrocatalyst layer (120), and a cathode fluid distribution layer (131) interposed between the cathode flow field plate (124) and the cathode electrocatalyst layer (121), wherein at least one of the anode and cathode fluid distribution layers decreases in permeability from an inlet to an outlet of the electrochemical fuel cell. Methods for making a substantially fluid impermeable sheet material having a non-uniform pattern of perforations are also provided. (FIG. - 4)