Claims
- 1. An electrode/electrolyte assembly comprising:
a ceramic electrolyte sheet; a positive air electrode disposed on a first surface of the sheet; and a negative fuel electrode disposed opposite the air electrode on a second surface of the sheet; wherein both the positive and negative electrodes comprise a conductive metal phase and a ceramic phase.
- 2. An assembly in accordance with claim 1 wherein the conductive metal phase is metallic silver or a silver alloy.
- 3. An assembly in accordance with claim 2 wherein the conductive metal phase is a silver alloy selected from the group consisting of silver-palladium and silver-platinum alloys.
- 4. An assembly in accordance with claim 3 wherein at least one of the first and second surfaces of the ceramic electrolyte sheet incorporates a stabilizing or electrically conducting interface layer.
- 5. An assembly in accordance with claim 4 wherein the interface layer is selected from the group consisting of stabilized zirconia, nickel cermets, and strontium-doped lanthanum manganite.
- 6. A solid oxide fuel cell incorporating an electrode/electrolyte assembly comprising:
a ceramic electrolyte sheet; a positive air electrode disposed on a first surface of the sheet; and a negative fuel electrode disposed opposite the air electrode on a second surface of the sheet; wherein both the positive and negative electrodes comprise a conductive metal phase and a ceramic phase.
- 7. A fuel cell in accordance with claim 6 wherein the ceramic phase is a polycrystalline ceramic.
- 8. A fuel cell in accordance with claim 7 wherein the polycrystalline ceramic in the ceramic phase is selected from the
group consisting of alumina, metal bismuthates, stabilized zirconia, partially stabilized zirconia, stabilized hafnia, partially stabilized hafnia, mixtures of zirconia and hafnia, ceria with zirconia, bismuth with zirconia, gadolinium, germanium, and mixtures thereof.
- 9. A fuel cell according to claim 8 wherein the polycrystalline ceramic in the ceramic phase is selected from the group consisting of partially stabilized zirconia or stabilized zirconia, the partially stabilized or stabilized zirconia being doped with a dopant selected from the group consisting of the oxides of Y, Ce, Ca, Mg, Sc, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, Ti, Sn, Nb, Ta, Mo, and W and mixtures thereof.
- 10. A fuel cell according to claim 6 wherein the electrolyte sheet is composed of a polycrystalline ceramic.
- 11. A fuel cell according to claim 10 wherein the polycrystalline ceramic is selected from the group consisting of stabilized zirconia, partially stabilized zirconia, stabilized hafnia, partially stabilized hafnia, mixtures of zirconia and hafnia, ceria with zirconia, bismuth with zirconia, gadolinium, germanium, and mixtures thereof.
- 12. A fuel cell according to claim 11 wherein the polycrystalline ceramic is selected from the group consisting of partially stabilized zirconia or stabilized zirconia, the partially stabilized or stabilized zirconia being doped with a dopant selected from the group consisting of the oxides of Y, Ce, Ca, Mg, Sc, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, Ti, Sn, Nb, Ta, Mo, and W and mixtures thereof.
- 13. A fuel cell according to claim 6 wherein the ceramic electrolyte sheet is from about 5 microns to about 45 microns in thickness.
- 14. A fuel cell according to claim 6 wherein the ceramic electrolyte sheet is a free-standing thin electrolyte.
- 15. A fuel cell according to claim 6 wherein the negative fuel electrode is infiltrated with an oxidation catalyst.
- 16. A fuel cell according to claim 15 wherein the oxidation catalyst is nickel.
- 17. A fuel cell according to claim 6 wherein at least one of the first and second surfaces of the ceramic electrolyte sheet incorporates a stabilizing or electrically conducting interface layer.
- 18. A fuel cell according to claim 17 wherein the interface layer has a composition selected from the group consisting of stabilized zirconia, nickel cermets, and strontium-doped lanthanum manganite.
Parent Case Info
[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60/205,353, filed May 18, 2001, entitled “Solid Oxide Fuel Cells with Symmetric Composite Electrode”, by Badding et al.
Provisional Applications (1)
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Number |
Date |
Country |
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60205353 |
May 2000 |
US |