Patent ID: 7541109

Claim:
A membrane electrode assembly for use in an associated direct oxidation fuel cell, comprising: (A) a protonically conductive, electronically non-conductive membrane electrolyte, having an anode aspect and a cathode aspect; (B) an anode catalyst disposed in contact with said anode aspect of the protonically conductive, electronically non-conductive membrane electrolyte; (C) a cathode catalyst that is suitable for oxygen electro-reduction reactions being disposed in contact with said cathode aspect of the protonically conductive, electronically non-conductive membrane electrolyte; (D) a microporous layer located between the cathode catalyst and a cathode backing layer, wherein the microporous layer blocks liquid water that is generated on the cathode aspect from migrating out through the cathode backing layer and forces the liquid water to travel across the protonically-conductive membrane to the anode catalyst for complete anodic oxidation, without any external supply or external redirection of the water, wherein the microporous layer comprises a layer of expanded PTFE facilitating cathode liquid water blocking; (E) an anode diffusion layer that is in contact with the anode catalyst on the membrane electrolyte; and (F) a fuel supply comprising neat methanol.