Patent ID: 7494735
Filing Date: 2009-02-24
Classification: H01M,Y02E

Abstract:
1. A fuel cell stack comprising: a first fuel cell segment and a second fuel cell segment sequentially arranged; a plurality of fuel cells disposed in each of said first and second fuel cell segments, each of said plurality of fuel cells having an anode passage, a cathode passage and a membrane electrode assembly interposed therebetween, said anode passage and said cathode passage being oriented in a unidirectional, gravity-assisted flow orientation; and a valve and piping manifold assembly positioned between and providing fluid communication between said first fuel cell segment and said second fuel cell segment, said manifold assembly being configurable between said anode and cathode passages of said first fuel cell segment and said anode and cathode passages of said second fuel cell segment to form one of a counter-current flow arrangement of said anode and cathode passages of said fuel cells within said fuel cell stack to provide counter-current flow and a parallel flow arrangement of said anode and cathode passages of said fuel cells within said fuel cell stack, to provide parallel flow, wherein each of said fuel cell segment further comprises: both said cathode inlet chamber and said cathode outlet chamber in fluid communication with said cathode passages, wherein said manifold assembly further comprises: a generally downwardly oriented cathode discharge pipe providing fluid communication between said cathode outlet chambers of both said first segment and said second segment, and wherein the fuel cell stack further comprises: