Electrolyte composition for solid oxide fuel cell, and solid oxide fuel cell

Patent metadata

Field	Value
Publication number	US-9692076-B2
Application number	US-201414201383-A
Country	US
Kind code	B2
Filing date	Mar 7, 2014
Priority date	Mar 7, 2014
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

The invention provides an electrolyte composition for solid oxide fuel cells, and a solid oxide fuel cell. The electrolyte composition has high electrical conductivity over a wide temperature range and is capable of imparting excellent output characteristics to a solid oxide fuel cell. Specifically, the invention provides a scandium oxide-stabilized zirconium oxide-based electrolyte composition used in a solid oxide fuel cell. The composition contains a compound represented by chemical formula (1): (ZrO 2 ) 1-x-a (Sc 2 O 3 ) x (M 2 O 3 ) a (1), wherein 0.09≦x≦0.11 and 0<a≦0.025, and M is at least one element selected from Sm and Nd. The compound has an electrical conductivity at 600° C. of 1.4×10 −2 (S/cm) or more and a power density at 600° C. of 25.0 (mW/cm 2 ) or more. The compound is not undergoing a cubic to rhombohedral phase transition at a temperature range of 25 to 850° C.

First claim

The invention claimed is:

1. A scandium oxide-stabilized zirconium oxide-based electrolyte composition used in a solid oxide fuel cell,
the composition comprising a compound represented by chemical formula (1) below:
(ZrO 2 )1− x−a (Sc 2 O 3 ) x (M 2 O 3 ) a   (1),

wherein 0.09≦x≦0.11 and 0<a≦0.025, and M is at least one element selected from Sm and Nd,
the M 2 O 3 being present in a state of solid solution in the scandium oxide-stabilized zirconium, the compound is produced by a coprecipitation method, a solid-phase reaction method, or a sol-gel method,
the compound having an electrical conductivity at 600° C. of 1.4×10-2 (S/cm) or more and a power density at 600° C. of 25.0 (mW/cm2) or more,
the compound not undergoing a cubic to rhombohedral phase transition at a temperature range of 25 to 850° C.

2. The electrolyte composition according to claim 1 , wherein the compound has an electrical conductivity at 550° C. of 8.5×10-3 (S/cm) or more and a power density at 550° C. of 10.0 (mW/cm2) or more.

3. The electrolyte composition according to claim 1 , wherein the compound has an electrical conductivity at 500° C. of 3.0×10-3 (S/cm) or more and a power density at 500° C. of 4.0 (mW/cm2) or more.

4. A scandium oxide-stabilized zirconium oxide-based electrolyte composition used in a solid oxide fuel cell,
the composition comprising a compound represented by chemical formula (1) below:
(ZrO 2 )1 −x−a (Sc 2 O 3 ) x (M 2 O 3 ) a   (1),

wherein 0.09≦x≦0.11 and 0<a≦0.015, and M is at least one element selected from Sm and Nd,
the M 2 O 3 being present in a state of solid solution in the scandium oxide-stabilized zirconium, the compound is produced by a coprecipitation method, a solid-phase reaction method, or a sol-gel method,
the compound having an electrical conductivity at 600° C. of 1.4×10-2 (S/cm) or more and a power density at 600° C. of 25.0 (mW/cm2) or more,
the compound not undergoing a cubic to rhombohedral phase transition at a temperature range of 25 to 850° C.

5. The electrolyte composition according to claim 4 , wherein the compound has an electrical conductivity at 550° C. of 8.5×10-3 (S/cm) or more and a power density at 550° C. of 10.0 (mW/cm2) or more.

6. The composition according to claim 4 , wherein the compound has an electrical conductivity at 500° C. of 3.0×10 −3 (S/cm) or more and a power density at 500° C. of 4.0 (mW/cm 2 ) or more.

7. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 1 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

8. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 2 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

9. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 3 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

10. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 4 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

11. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 5 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

12. A solid oxide fuel cell having a single cell structure including a solid electrolyte comprising the electrolyte composition of claim 6 , the solid electrolyte having a fuel electrode on one surface and an air electrode on the opposite surface.

Assignees

• Daiichi Kigenso Kagaku Kogyo
• Inst Nat Colleges Tech Japan

Inventors

• Tamazaki Fuminori
• Nakayama Susumu
• Nakajima Yasushi

Classifications

• Y02E60/525

  Cross-Sectional Technologies · mapped topic

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• Y02P70/56

  Cross-Sectional Technologies · mapped topic

• H01M2300/0077

  based on zirconium oxide · CPC title

• H01M8/1253 Primary

  the electrolyte containing zirconium oxide · CPC title