Electrolyte Supported Cell Designed for Longer Life and Higher Power

• US 20120028162A1
• Filed: 10/07/2011
• Published: 02/02/2012
• Est. Priority Date: 11/13/2007
• Status: Active Grant

• Current Assignee: Bloom Energy Corporation
• Original Assignee: Bloom Energy Corporation
• Inventors: Gottmann, Matthias, Nguyen, Dien, Batawi, Emad El, Armstrong, Tad, Wang, Gonghou, Hickey, Darren, Couse, Stephen
• Granted Patent: US 8,999,601 B2
• Time in Patent Office: Days
• US Class Current: 429/480
• CPC Class Codes: H01M 4/8885 Sintering or firing
• CPC Class Codes: H01M 4/9025 Oxides specially used in fuel cell operating at high temperature, e.g. SOFC
• CPC Class Codes: H01M 4/9066 of metal-ceramic composites or mixtures, e.g. cermets
• CPC Class Codes: H01M 8/1253 the electrolyte containing zirconium oxide
• CPC Class Codes: H01M 8/126 the electrolyte containing cerium oxide
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 156/1051 by folding

Abstract

A solid oxide fuel cell (SOFC) includes a cathode electrode, an anode electrode, and a solid oxide electrolyte located between the anode electrode and the cathode electrode. The cathode electrode is a porous ceramic layer infiltrated with a cathode catalyst material, and the anode electrode is a porous ceramic layer infiltrated with an anode catalyst material, and the electrolyte is a ceramic layer having a lower porosity than the anode and the cathode electrodes. A ceramic reinforcing region may be located adjacent to the riser opening in the electrolyte.

Claims

1. A solid oxide fuel cell (SOFC), comprising:

an anode electrode;

a cathode electrode; and

a solid oxide electrolyte located between the anode electrode and the cathode electrode;

wherein;

the anode electrode comprises a porous first ceramic layer infiltrated with an anode catalyst material;

the cathode electrode comprises a porous second ceramic layer infiltrated with a cathode catalyst material; and

the electrolyte comprises a third ceramic layer having a lower porosity than the first and the second ceramic layers.

2. The SOFC of claim 1, wherein the first, the second and the third ceramic layers comprise a same material.

3. The SOFC of claim 2, wherein the first, the second and the third ceramic layers comprise SSZ or YSZ.

4. The SOFC of claim 3, wherein the first, the second and the third ceramic layers comprise 8SSZ or 8YSZ.

5. The SOFC of claim 1, wherein a material of the third ceramic layer is different from a material of the first and the second ceramic layers.

6. The SOFC of claim 5, wherein the first and the second ceramic layers have a higher strength and a lower ionic conductivity than the third ceramic layer.

7. The SOFC of claim 6, wherein the first and the second ceramic layers comprise YSZ and the third ceramic layer comprises SSZ.

8. The SOFC of claim 1, further comprising:

a fourth ceramic layer located between the first ceramic layer and the third ceramic layer; and

a fifth ceramic layer located between the second ceramic layer and the third ceramic layer.

9. The SOFC of claim 8, wherein:

the first, the second and the third ceramic layers comprise stabilized zirconia layers; and

the fourth and the fifth ceramic layers comprise doped ceria layers.

10. The SOFC of claim 1, further comprising a non continuous ceramic support layer located on the anode electrode or on the cathode electrode.

11. The SOFC of claim 1, wherein a peripheral portion of the porous first ceramic layer is filled with a seal material.

12. The SOFC of claim 1, wherein a portion of the third ceramic layer is folded over a peripheral portion of first ceramic layer.

13. The SOFC of claim 1, wherein:

the electrolyte is about 25 to about 75 microns thick; and

the anode electrode and the cathode electrode layer are about 20 to about 100 microns thick.

14. The SOFC of claim 1, wherein the anode electrode is thinner than the cathode electrode.

15. The SOFC of claim 1, wherein the SOFC is incorporated into a stack comprising a plurality of planar SOFCs separated by gas separator/interconnect plates.

16. A method of making a solid oxide fuel cell (SOFC), comprising:

providing a structure comprising a porous first ceramic layer, a porous second ceramic layer and a third ceramic layer electrolyte having a lower porosity than the first and the second ceramic layers;

infiltrating an anode electrode catalyst into the first porous ceramic layer to form an anode electrode; and

infiltrating a cathode electrode catalyst into the second porous ceramic layer to form a cathode electrode.

17. The method of claim 16, wherein the structure is formed by providing a pore former into a first green ceramic layer and into a second green ceramic layer but not into a third green ceramic layer followed by heating the structure to burn away the pore former.

18. The method of claim 17, wherein the structure is formed by tape casting the first, the second and the third green ceramic layers followed by sintering.

19. The method of claim 18, wherein the structure is formed by multi layer tape casting.

20. The method of claim 18, wherein the structure is formed by roll compaction of the tape cast layers.

21. The method of claim 18, wherein the structure is formed by uniaxial or isostatic pressing of the tape cast layers.

22. The method of claim 21, wherein the pressing is performed with or without compatible organic adhesives.

23. The method of claim 16, wherein the structure further comprises:

a fourth ceramic layer located between the first ceramic layer and the third ceramic layer; and

a fifth ceramic layer located between the second ceramic layer and the third ceramic layer.

24. The method of claim 16, further comprises filling a peripheral portion of the porous first ceramic layer with a seal material.

25. The SOFC of claim 16, further comprising folding a portion of the third ceramic layer over a peripheral portion of first ceramic layer.