Fuel cell stack with internal fuel manifold configuration

1. A fuel cell stack, comprising:

a plurality of plate shaped fuel cells which are internally manifolded on a fuel side and externally manifolded on an oxidizer side; and

at least one fuel manifold located between adjacent fuel cells; and

a plurality of risers, wherein the plurality of risers comprise channels which extend through the plurality of plate shaped fuels cells and respective interconnects located in the fuel cell stack;

wherein the at least one manifold comprises:

a plate shaped box comprising at least one fuel delivery opening in fluid communication with fuel cell fuel inlet riser openings and at least one fuel outlet opening in fluid communication with fuel cell fuel outlet riser openings, wherein the plurality of plate shaped fuel cells which are internally manifolded on the fuel side and externally manifolded on the oxidizer side surround the plate shaped box;

a fuel delivery port comprising a fuel inlet conduit adapted to provide a fuel inlet stream into the fuel manifold, and

a fuel outlet port comprising a fuel outlet conduit adapted to remove a fuel outlet stream from the fuel manifold; and

wherein the plate shaped box comprises a separate component from the fuel cells.

2. The stack of claim 1 , wherein the fuel inlet and outlet riser openings are positioned substantially perpendicularly to the fuel inlet and the fuel outlet conduits.

3. The stack of claim 2 , wherein:

the at least one fuel manifold comprises a first fuel delivery opening and a first fuel outlet opening located in a first major plate face of the plate shaped box, and a second fuel delivery opening and a second fuel outlet opening located in a second major plate face of the plate shaped box; and

the fuel inlet conduit and the fuel outlet conduit are connected to at least one edge of the plate shaped box.

4. The stack of claim 1 , further comprising fuel inlet riser openings in the plurality of fuel cells having a cross sectional width of 0.15 to 0.5 inches.

5. The stack of claim 1 , further comprising a plurality of fuel delivery ports, wherein each of the plurality of fuel delivery ports is connected to a respective one of a plurality of manifolds to provide fuel to a portion of the plurality fuel cells in each stack.

6. The stack of claim 1 , wherein the plurality of plate shaped fuel cells are stacked in a vertical direction.

7. The stack of claim 6 , wherein the plate shaped box comprises:

a top wall, a bottom wall, two opposite end walls, and two opposite side walls, said end walls and said side walls extending upwardly from the bottom wall to the top wall,

wherein said side walls and end walls comprise edge surfaces, and

wherein said top and bottom walls comprise first and second major plate surfaces of the plate shaped box.

8. A fuel cell stack, comprising:

a plurality of plate shaped fuel cells which are internally manifolded on a fuel side and externally manifolded on an oxidizer side; and

at least one fuel manifold located between adjacent fuel cells;

wherein the at least one manifold comprises:

a plate shaped box comprising at least one fuel delivery opening in fluid communication with fuel cell fuel inlet riser openings and at least one fuel outlet opening in fluid communication with fuel cell fuel outlet riser openings;

a fuel delivery port comprising a fuel inlet conduit adapted to provide a fuel inlet stream into the fuel manifold, and

a fuel outlet port comprising a fuel outlet conduit adapted to remove a fuel outlet stream from the fuel manifold; and

a plurality of risers, wherein the plurality of risers comprise channels which extend through the plurality of plate shaped fuels cells and respective interconnects located in the fuel cell stack;

wherein the plate shaped box comprises a top wall, a bottom wall, two opposite end walls, and two opposite side walls, said end walls and said side walls extending upwardly from the bottom wall to the top wall, wherein said side walls and end walls comprise edge surfaces, wherein said top and bottom walls comprise first and second major plate surfaces of the plate shaped box,

wherein at least one of the top and the bottom walls of the plate shaped box are located adjacent to the plurality of plate shaped fuel cells, and

wherein the plurality of plate shaped fuel cells which are internally manifolded on the fuel side and externally manifolded on the oxidizer side surround the plate shaped box.

9. The stack of claim 8 , wherein the fuel inlet and outlet riser openings are positioned substantially perpendicularly to the fuel inlet and the fuel outlet conduits.

10. The stack of claim 9 , wherein:

the at least one fuel manifold comprises a first fuel delivery opening and a first fuel outlet opening located in the first major plate surface of the plate shaped box, and a second fuel delivery opening and a second fuel outlet opening located in the second major plate surface of the plate shaped box; and

the fuel inlet conduit and the fuel outlet conduit are connected to at least one edge surface of the plate shaped box.

11. The stack of claim 8 , further comprising fuel inlet riser openings in the plurality of fuel cells having a cross sectional width of 0.15 to 0.5 inches.

12. The stack of claim 8 , further comprising a plurality of fuel delivery ports, wherein each of the plurality of fuel delivery ports is connected to a respective one of a plurality of manifolds to provide fuel to a portion of the plurality fuel cells in each stack.

13. The stack of claim 8 , wherein the plurality of plate shaped fuel cells are stacked in a vertical direction.

14. The stack of claim 8 , wherein the plate shaped box comprises a separate component from the fuel cells.

15. The stack of claim 1 , wherein the plurality of plate shaped fuel cells are stacked vertically over and under the plate shaped box.

16. The stack of claim 8 , wherein the plurality of plate shaped fuel cells are stacked vertically over and under the plate shaped box.

17. A fuel cell stack, comprising:

a plurality of plate shaped fuel cells which are internally manifolded on a fuel side and externally manifolded on an oxidizer side; and

at least one fuel manifold located between adjacent fuel cells; and

a plurality of interconnects and a plurality of fuel flow channels,

wherein each fuel flow channel is located between an anode electrode of each plate shaped fuel cell and a respective interconnect plate in the fuel cell stack, such that fuel flows from the fuel inlet riser opening on one side of the plate shaped fuel cell through each fuel flow channel into the fuel outlet riser opening on a second side of the plate shaped fuel cell;

wherein the at least one manifold comprises:

a plate shaped box comprising at least one fuel delivery opening in fluid communication with fuel cell fuel inlet riser openings and at least one fuel outlet opening in fluid communication with fuel cell fuel outlet riser openings, wherein the plurality of plate shaped fuel cells which are internally manifolded on the fuel side and externally manifolded on the oxidizer side surround the plate shaped box;

a fuel delivery port comprising a fuel inlet conduit adapted to provide a fuel inlet stream into the fuel manifold, and

a fuel outlet port comprising a fuel outlet conduit adapted to remove a fuel outlet stream from the fuel manifold; and

wherein the plate shaped box comprises a separate component from the fuel cells.

18. A fuel cell stack, comprising:

a plurality of plate shaped fuel cells which are internally manifolded on a fuel side and externally manifolded on an oxidizer side; and

at least one fuel manifold located between adjacent fuel cells;

wherein the at least one manifold comprises:

a plate shaped box comprising at least one fuel delivery opening in fluid communication with fuel cell fuel inlet riser openings and at least one fuel outlet opening in fluid communication with fuel cell fuel outlet riser openings;

a fuel delivery port comprising a fuel inlet conduit adapted to provide a fuel inlet stream into the fuel manifold, and

a fuel outlet port comprising a fuel outlet conduit adapted to remove a fuel outlet stream from the fuel manifold; and

a plurality of interconnects and a plurality of fuel flow channels,

wherein each fuel flow channel is located between an anode electrode of each plate shaped fuel cell and a respective interconnect plate in the fuel cell stack, such that fuel flows from the fuel inlet riser opening on one side of the plate shaped fuel cell through each fuel flow channel into the fuel outlet riser opening on a second side of the plate shaped fuel cell;

wherein the plate shaped box comprises a top wall, a bottom wall, two opposite end walls, and two opposite side walls, said end walls and said side walls extending upwardly from the bottom wall to the top wall,

wherein said side walls and end walls comprise edge surfaces, wherein said top and bottom walls comprise first and second major plate surfaces of the plate shaped box,

wherein at least one of the top and the bottom walls of the plate shaped box are located adjacent to the plurality of plate shaped fuel cells, and

wherein the plurality of plate shaped fuel cells which are internally manifolded on the fuel side and externally manifolded on the oxidizer side surround the plate shaped box.