Internal PEM fuel cell water management

• Main Authors: HARRINGTON MICHAEL D, BREAULT RICHARD D, SRIBNIK FREDERICK
• Format: Patent
• Language: English
• Published: 14.10.2008
• Subjects: BASIC ELECTRIC ELEMENTS; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

Water transfer means ( 86 ) transfers fuel cell product water from a cathode water transport plate ( 34 ) to an anode water transport plate ( 23 ) of the same or a different fuel cell, wholly within a fuel cell stack ( 50 ), (disposed within each fuel cell of a fuel cell stack ( 50 )). The water transfer means may be a very high permeability proton exchange membrane ( 21 a), a water transfer band ( 90 ) such as silicon carbide particles, a porous water transfer zone ( 107 ), with or without a flow restrictor ( 109 ), internal water manifolds ( 112, 113 ) which extend through an entire fuel cell stack, or internal manifolds ( 112 a , 112 b, 112 c, 112 d, 113 a, 113 b, 113 c, 113 d) which extend only through groups of cells between solid plates ( 71 ). As an example, 90% product water may be removed as vapor in oxidant exhaust, 30% may be transferred through the water transfer means ( 86 ) from cathode water transport plates to anode water transport plates, of which 20% may flow from the anode to the cathode, the net result of osmosis and proton drag, and 10% may exit the anode water transport plates as liquid water.