Abstract: A method of operating a low pressure drop fuel cell stack comprising a plurality of low pressure drop fuel cells wherein during low pressure and low power operation, a heat transfer rate of a cathode flow field plate of each fuel cell is greater than a heat transfer rate of an anode flow field plate of the same fuel cell. Thus, a temperature gradient is created between an anode electrode and a cathode electrode of each fuel cell, as well as reactant fluids in at least one anode flow field and at least one cathode flow field of the same fuel cell.

Abstract: An electrochemical fuel cell stack with improved reactant manifolding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold and interconnecting the cathodes to an oxidant manifold are formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the contacted electrode. The non-active surfaces of adjoining separator plates in a fuel cell stack cooperate to provide passageways for directing both reactants from respective stack fuel and oxidant supply manifolds to the appropriate electrodes. The fuel and oxidant reactant streams passageways are fluidly isolated from each other, although they both traverse adjoining non-active surfaces of the same pair of plates.

Abstract: An electrochemical fuel cell stack with improved reactant man folding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold and interconnecting the cathodes to an oxidant manifold are formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the contacted electrode. The non-active surfaces of adjoining separator plates in a fuel cell stack cooperate to provide passageways for directing both reactants from respective stack fuel and oxidant supply manifolds to the appropriate electrodes. The fuel and oxidant reactant streams passageways are fluidly isolated from each other, although they both traverse adjoining non-active surfaces of the same pair of plates.

Abstract: An electrochemical fuel cell stack with improved reactant man folding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold and interconnecting the cathodes to an oxidant manifold are formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the contacted electrode. The non-active surfaces of adjoining separator plates in a fuel cell stack cooperate to provide passageways for directing both reactants from respective stack fuel and oxidant supply manifolds to the appropriate electrodes. The fuel and oxidant reactant streams passageways are fluidly isolated from each other, although they both traverse adjoining non-active surfaces of the same pair of plates.

Abstract: An electrochemical fuel cell stack with improved reactant manifolding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold, and interconnecting the cathodes to an oxidant manifold, comprise at least one fluid passageway formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the adjacent electrode. The ports comprise walls that have surfaces that are angled more than 0 degrees and less than 90 degrees with respect to the direction of fluid flow in the fluid passageway upstream of the port. During operation, electrochemical fuel cell stacks comprising fluid ports with angled walls benefit from reduced pressure loss.

Abstract: An electrochemical fuel cell stack with improved reactant manifolding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold, and interconnecting the cathodes to an oxidant manifold, comprise at least one fluid passageway formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the adjacent electrode. The ports comprise walls that have surfaces that are angled more than 0 degrees and less than 90 degrees with respect to the direction of fluid flow in the fluid passageway upstream of the port. During operation, electrochemical fuel cell stacks comprising fluid ports with angled walls benefit from reduced pressure loss.

Abstract: An electrochemical fuel cell stack with improved reactant manifolding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold, and interconnecting the cathodes to an oxidant manifold, comprise at least one fluid passageway formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the adjacent electrode. The ports comprise walls that have surfaces that are angled more than 0 degrees and less than 90 degrees with respect to the direction of fluid flow in the fluid passageway upstream of the port. During operation, electrochemical fuel cell stacks comprising fluid ports with angled walls benefit from reduced pressure loss.

Abstract: An electrochemical fuel cell stack with improved reactant manifolding and sealing includes a pair of separator plates interposed between adjacent membrane electrode assemblies. Passageways fluidly interconnecting the anodes to a fuel manifold and interconnecting the cathodes to an oxidant manifold are formed between adjoining non-active surfaces of the pairs of separator plates. The passageways extend through one or more ports penetrating the thickness of one of the plates thereby fluidly connecting the manifold to the opposite active surface of that plate, and the contacted electrode. The non-active surfaces of adjoining separator plates in a fuel cell stack cooperate to provide passageways for directing both reactants from respective stack fuel and oxidant supply manifolds to the appropriate electrodes. The fuel and oxidant reactant streams passageways are fluidly isolated from each other, although they both traverse adjoining non-active surfaces of the same pair of plates.