Patent ID: 6048634
Filing Date: 2000-04-11
Classification: H01M,Y02E

Abstract:
A reactant flow system for a Proton Exchange Membrane (PEM) fuel cell stack using a ""water-soluble-fuel"" fuel cell comprising a plurality of cells in which each cell of said PEM fuel cell stack comprises a positive cathode electrode at which reactant oxygen reduction takes place, a negative anode electrode at which reactant fuel is oxidized, a proton-exchange electrolyte membrane disposed between said positive cathode electrode and said negative anode electrode, and wherein between pairs of adjacent cells are disposed a cathode flow-field for distributing oxygen to an adjacent cathode electrode, at a side of said adjacent cathode electrode opposite a side in contact with a corresponding proton-exchange electrolyte membrane, an anode flow-field for distributing fuel to an adjacent anode electrode, at a side of said adjacent anode electrode opposite a side in contact with a corresponding proton-exchange electrolyte membrane, and a reactant separator layer disposed between said cathode flow-field and said anode flow-field, said reactant separator layer isolating said oxygen in said cathode flow-field from said fuel in said anode flow-field, said PEM fuel cell stack being configured to prevent said cathode electrode from flooding, wherein said flow-field for at least one reactant of said reactant oxygen and said reactant fuel, includes at least one pair of reactant flow channels, and further wherein at least a portion of each reactant flow channel is operatively adjacent to at least one corresponding flow channel such that a reactant flow direction in the flow channel is opposite a reactant flow direction in at least one operatively adjacent flow channel, and each reactant flow channel has a reactant inlet and a reactant outlet.