Patent ID: 8580457

Claim:
A fuel cell stack comprising: a) at least one bipolar plate assembly including a first generally planar plate body having opposing first and second generally planar faces, the first face including: i) an opening defined by the first plate body for passage of a reactant therethrough; ii) a first reactant flow field defined thereon; and iii) a first raised surface on the first face substantially surrounding the opening, the first raised surface being adapted and configured to mate with a second surface on a face of an adjacent bipolar plate assembly, wherein the first raised surface and second surface create a flow obstruction when the raised surfaces are mated; the second face including: iv) a first channel; wherein a first conduit penetrates through the plate to connect the first reactant flow field to the first channel; b) a first membrane electrode assembly in operable communication with the first reactant flow field; c) a reactant manifold in fluid communication with the reactant flow field by way of the first channel, the reactant manifold being adapted and configured to facilitate transport of a reactant through the fuel cell stack; and d) a layer of encapsulating material disposed about the first plate body, membrane electrode assembly and reactant manifold, wherein the encapsulating material is substantially prevented from flowing into the opening defined by the first plate body by the flow obstruction and wherein the encapsulating material substantially encloses the manifold and seals the manifold in a gas-tight manner at an interface between the encapsulating material and the membrane electrode assembly.