Patent ID: 7407721

Claim:
A direct oxidation fuel cell, comprising: (A) a membrane, sufficiently thin to allowe a rate of internal supply of water from a cathode side to an anode side of the fuel cell to be enhanced, said membrane intimately interfacing with a catalyst layer along each of said membrane's major surfaces, having an anode aspect and a cathode aspect; (B) a fuel cell housing enclosing said fuel cell; (C) a fuel chamber in fluid communication with said anode aspect, said fuel chamber having no liquid outlet, and being filled or fed with fuel and said fuel chamber having a passive mass transport barrier that is configured to defines a rate of fuel delivery of about 10-50% higher than a rate of anodic consumption of methanol in the fuel cell; and (D) effective water supply from cathode to anode within said fuel cell, so that water management in said fuel cell is achieved without water transport from cathode to anode external to the active volume of the fuel cell.