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Einstellungen

Einstellungen

1. US20040067400 - Fuel cell assembly

Anmerkung: Text basiert auf automatischer optischer Zeichenerkennung (OCR). Verwenden Sie bitte aus rechtlichen Gründen die PDF-Version.

Claims

1. Fuel cell arrangement with fuel cells ( 12) that are arranged in the form of a fuel cell stack ( 10; 110; 210; 310; 410; 510), whereby the fuel cells each contain an anode ( 1), a cathode ( 2), and an electrolyte matrix ( 3) that is arranged between them, together with an anode inlet ( 13; 313; 413; 513) for admitting fresh fuel gas to the anodes ( 1), and an anode outlet ( 14; 114; 214; 314; 414; 514) for carrying away spent fuel gas from the anodes ( 1), together with a cathode inlet ( 15; 315; 415; 515) for admitting fresh cathode gas to the cathodes ( 2), and a cathode outlet ( 16; 316; 416; 516) for carrying away spent cathode gas from the cathodes ( 2), as well as an electrical heating device ( 20; 120; 220; 320; 420; 520) in order to heat the cathode inlet gas, characterized in that the electrical heating device ( 20; 120; 220; 320; 420; 520) is formed from a structure comprising an electrically conducting foam material, whereby the gas, which is to be heated, flows through this structure, and whereby this structure is provided with electrical connections ( 22; 23) for connection to a supply of electric current.
2. Fuel cell arrangement in accordance with claim 1, characterized in that the foam structure of the electrical heating device ( 20; 120; 220; 320; 420; 520) comprises high grade steel, preferably FeCrAlY, or steel, or a conducting ceramic.
3. Fuel cell arrangement in accordance with claim 1 or 2, characterized in that the electrical heating device ( 20; 120; 220; 320; 420; 520) comprises several individual segments ( 124 a, 124 b; 224 a, 224 b) that have each been provided with electrical connections ( 22, 23), whereby the gas, which is to be heated, flows through these segments.
4. Fuel cell arrangement in accordance with claim 3, characterized in that the segments ( 124 a, 124 b; 224 a, 224 b) of the electrical heating device ( 20; 120; 220; 320; 420; 520) are arranged at different locations within the gas stream that is to be heated.
5. Fuel cell arrangement in accordance with claim 3 or 4, characterized in that the segments ( 124 a, 124 b; 224 a, 224 b) of the electrical heating device ( 20; 120; 220; 320; 420; 520) each have connections ( 22, 23), which are electrically separated from one another, whereby these connections are capable of being connected, separately from one another as required, to the supply of electric current.
6. Fuel cell arrangement in accordance with one of the claims 1 through 5, characterized in that the electrical heating device ( 320; 420; 520) is arranged in the gas stream prior to the cathode inlet ( 315; 415; 515) in order to heat the cathode gas that is to be admitted to the cathodes ( 2) of the fuel cells ( 12).
7. Fuel cell arrangement in accordance with claim 6, characterized in that the cathode outlet [sic; anode outlet?] ( 314; 414; 514) is connected to the cathode inlet ( 315; 415; 515) via a gas carrying pathway ( 340; 440; 540) in order to admit at least a portion of the spent fuel gas to the cathodes ( 2) of the fuel cells ( 12), and that the electrical heating device ( 320; 420; 520) is arranged in the gas carrying pathway ( 340; 440; 540) after the anode outlet ( 314; 414; 514) and prior to the cathode inlet ( 315; 415; 515).
8. Fuel cell arrangement in accordance with claim 7, characterized in that a mixing chamber ( 330; 430; 530) is provided in which, prior to admission to the cathode inlet ( 315; 415; 515), the cathode gas is mixed with the stream of spent fuel gas that leaves the anode outlet ( 314; 414; 514), whereby this mixing chamber is provided in the gas carrying pathway ( 340; 440; 540) between the anode outlet ( 314; 414; 514) and the cathode inlet ( 315; 415; 515), and in that the electrical heating device ( 320; 420; 520), together with the mixing chamber ( 330, 430, 530), is arranged in the gas stream between the anode outlet ( 314; 414; 514) and the cathode inlet ( 315; 415; 515).
9. Fuel cell arrangement in accordance with claims 7 and 8, characterized in that the electrical heating device ( 320) is arranged directly prior to the cathode inlet ( 315).
10. Fuel cell arrangement in accordance with claim 9, characterized in that the foam structure of the electrical heating device ( 320) occupies essentially the entire cross-section of the cathode inlets ( 315) of all the fuel cells ( 12) in the fuel cell stack ( 310).
11. Fuel cell arrangement in accordance with claims 7 and 8, characterized in that the electrical heating device ( 420) is arranged at the outlet of the mixing chamber ( 430).
12. Fuel cell arrangement in accordance with claims 7 and 8, characterized in that the electrical heating device ( 520) is provided integrally with the mixing chamber ( 530).
13. Fuel cell arrangement in accordance with claim 12, characterized in that the foam structure of the electrical heating device ( 120; 220; 520) is arranged directly at the anode outlet ( 114; 214; 514) and essentially occupies the entire cross-section of the anode outlets ( 114; 214; 514) of all the fuel cells in the fuel cell stack, and it simultaneously forms at least a portion of the mixing volume of the mixing chamber ( 130; 230; 530).
14. Fuel cell arrangement in accordance with claim 13, characterized in that the gas stream comprising spent anode gas, which leaves the anode outlets ( 114; 214; 514) of the fuel cells, enters the mixing volume of the mixing chamber ( 130; 230; 530) from a first direction, and in that the stream of mixed in cathode gas enters the mixing volume of the mixing chamber ( 130; 230; 530) from a second direction, and in that the mixed streams of spent anode gas and cathode gas enter the mixing volume of the mixing chamber ( 130; 230; 530) in a third direction.
15. Fuel cell arrangement in accordance with claims 12, 13, or 14 in combination with claims 3, 4, or 5, characterized in that one or more first individual segments ( 124 a; 224 a) of the electrical heating device ( 120; 220) are arranged in the gas stream comprising the cathode gas that is admitted to the mixing chamber ( 130; 230), and that one or more second individual segments ( 124 b; 224 b) of the electrical heating device ( 120; 220) are arranged in the gas stream comprising the spent anode gas that leaves the anode outlets ( 114; 214), whereby either the stream of spent anode gas alone or the streams of spent anode gas and mixed in cathode gas flow through the second segments ( 124 b; 224 b).
16. Fuel cell arrangement in accordance with one of the claims 3 through 15, characterized in that the individual segments ( 124 a, 124 b; 224 a, 224 b) of the electrical heating device ( 120; 220) are formed from sheets comprising the electrically conducting foam material, whereby these sheets are arranged parallel to one another.
17. Fuel cell arrangement in accordance with one of the claims 1 through 16, characterized in that one or more fuel cell stacks ( 310; 410; 510) are arranged in a thermally insulating protective housing ( 350; 450; 550), which surrounds the flow pathways of the cathode gas and fuel gas, and that the fuel cell stack(s) ( 310; 410; 510) and the electrical heating device ( 320; 420; 520) are linked to one another and are arranged, in amalgamated form, in the thermally insulating protective housing ( 350; 450; 550).
18. Fuel cell arrangement in accordance with one of the claims 1 through 17, characterized in that a catalytic combustion device for after-burning the combustible residual components of the spent fuel gas, which leaves the anode outlets ( 114; 214; 314; 414; 514), is provided and that it is connected to the anode outlet ( 114; 214; 314; 414; 514) and arranged downstream thereof.
19. Fuel cell arrangement in accordance with claim 18, characterized in that the catalytic combustion device is formed from a catalytic coating on the foam structure of the electrical heating device ( 120; 220; 320; 420; 520).