Bipolar separator for fuel cell stack
View Patent ↗It is described a bipolar separator for polymer membrane fuel cell stacks, delimited by two sheets provided with fluid passage holes connected by means of a corrugated element and comprising a passage section for a thermostatting liquid, which allows to achieve the withdrawal of heat from the adjacent cells and the humidification and distribution of gases with a single integrated piece, simplifying the assembly and the hydraulic sealing of the stack.
1. A bipolar separator for a fuel cell stack, comprising:
a cathode sheet and an anode sheet, at least one of said sheets provided with fluid passage holes;
at least one corrugated conductive element,
wherein said cathode sheet and said anode sheet are welded or metallurgically bonded through said at least one corrugated conductive element; wherein a cooling fluid passage is formed between the corrugated conductive element and at least one of said cathode sheet and anode sheet; and wherein said at least one corrugated conductive element adjoins said cathode and anode sheets only in one or more peripheral regions of the separator.
2. The separator of claim 1 , wherein said fluid passage holes are gas feed and/or discharge holes disposed in one or more peripheral regions of said at least one sheet.
3. The separator of claim 1 wherein said fluid passage holes comprise calibrated orifices for feeding a flow of said cooling fluid into a fuel cell adjacent to the separator.
4. The separator of claim 1 wherein a cooling fluid passage section comprises at least one reticulated element interposed between said cathode sheet and said anode sheet.
5. The separator of claim 4 wherein said at least one reticulated element is an electrically conductive, optionally metallic element.
6. The separator of claim 5 wherein said at least one conductive reticulated element is selected from the group consisting of metal foams, metal meshes, expanded sheets and sintered metallic materials.
7. The separator of claim 1 wherein at least one of said anode and cathode sheets comprises a sealing gasket secured to the side opposite to the one whereto said corrugated conductive element is welded or metallurgically bonded.
8. The separator of claim 1 wherein at least one of said anode and cathode sheets comprises a current collector welded or metallurgically bonded to the side opposite to the one whereto said corrugated conductive element is welded or metallurgically bonded.
9. The separator of claim 8 wherein said current collector is an electrically conductive reticulated element optionally selected from the group consisting of metal foams, metal meshes, expanded sheets and sintered metallic materials.
10. A fuel cell stack comprising at least one separator of claim 1 .
11. The stack of claim 10 comprising at least one feed or discharge duct in communication with said fluid passage holes.
12. The separator of claim 1 , wherein the fluid passage holes in said anode and/or said cathode sheet are gas feed and/or discharge holes located only in one or more peripheral regions.
13. The separator of claim 1 , further comprising a reticulated element interposed between said anode sheet and said cathode sheet, forming a cooling fluid passage section between said anode sheet and cathode sheet, wherein at least one of said anode sheet and said cathode sheet has fluid passage holes in a region in contact with the reticulated element.