Interconnect for a fuel cell, a method for manufacturing an interconnect for a fuel cell
An interconnect for a fuel cell is made of pressed metal sheet. The interconnect integrates inlets and outlets, flow distributing inlet and outlet-zones seal surfaces and flow paths on both sides of the interconnect all formed and defined by discrete point or oblong protrusions made by the deformation of the sheet. A protrusion on one side of the interconnect corresponds to an indentation on the other side, but since the interconnect consists of three levels, the first side of the interconnect can be designed substantially independently of the second side.
1. An interconnect for a fuel cell comprising a plurality of flow providing manifolds, the interconnect comprises a first and a second side, each side having flow paths, one or more flow inlets and inlet zones distributing the flow between said flow paths, one or more flow outlets and outlet zones, protrusions formed of protruding seal surfaces, protruding contact areas and protruding seal surface supports, said flow paths are formed between the protruding seal surfaces and the protruding contact areas,
wherein said interconnect is made of a metal sheet comprising at least a mid level defined by the metal sheet part without protrusions, a first level defined by the protrusions on the first side and a second level defined by the protrusions on the second side such that a protrusion on the first side corresponds an indentation on the second side extending into the first level and a protrusion on the second side corresponds an indentation on the first side extending into the second level; and the flow inlet zones, the flow outlet zones, the flow paths, the protruding contact areas, the protruding seal surface supports and the protruding seal surfaces are integrated in both sides of said metal sheet.
2. An interconnect according to claim 1 , wherein the position of said seal surfaces are supported by indentations.
3. An interconnect according to claim 1 , wherein one or more of said seal surfaces on the first or second side comprise(s) at least one purge channel.
4. An interconnect according to claim 1 , wherein said seal surfaces and said contact areas are flexible.
5. An interconnect according to claim 1 , wherein said metal sheet has a thickness between 50 and 400 μm, preferably between 100 and 250 λm.
6. An interconnect according to claim 1 , wherein said metal sheet consist of chrome steel or a nickel alloy.
7. An interconnect according to claim 1 , wherein said flow paths on the first side and second side of said interconnect are designed to provide even flow distribution between each of the flow paths on the first side and the second side, respectively.
8. An interconnect according to claim 1 , wherein the one or more flow inlets on the first or second side of said interconnect is internal and the one or more flow inlets on the second or first side, respectively, of said interconnect is external.
9. An interconnect according to claim 1 , wherein said flow paths are intersected by by-pass flow paths comprising breaches in the protruding contact areas.
10. An interconnect according to claim 1 , wherein said flow paths are intersected by indentations.
11. An interconnect according to claim 1 , wherein the protruding contact areas on the first or second side of said interconnect comprise discrete points and the protruding contact areas on the second or first side respectively comprise oblong ridges.
12. A fuel cell repeating unit comprising an electrolyte, an anode, a cathode and an interconnect according to claim 1 .
13. A fuel cell repeating unit according to claim 12 , wherein the fuel cell is a high temperature fuel cell.
14. A fuel cell repeating unit according to claim 12 , wherein the fuel cell is a solid oxide fuel cell or a molten carbonate fuel cell.
15. A fuel cell repeating unit according to claim 12 , wherein the fuel cell is a PEM proton exchange membrane fuel cell.
16. A fuel cell repeating unit according to claim 12 , wherein the fuel cell is a DMFC direct methanol fuel cell.
17. A fuel cell stack comprising at least two fuel cell repeating units according to claim 12 .