Connecting material for solid oxide fuel cell, manufacturing method therefor, and solid oxide fuel cell

Patent metadata

Field	Value
Publication number	US-11374231-B2
Application number	US-201816755186-A
Country	US
Kind code	B2
Filing date	Oct 19, 2018
Priority date	Oct 20, 2017
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

The present specification relates to an interconnect for a solid oxide fuel cell, a method for preparing the same, and a solid oxide fuel cell.

First claim

What is claimed is:

1. An interconnect for a solid oxide fuel cell comprising:
a conductive substrate; and
a ceramic protective layer on a first surface of the conductive substrate,
wherein the ceramic protective layer comprises a compound of Chemical Formula 1 that has a spinel structure:
Mn 1.5-0.5(x1+x2) Co 1.5-0.5(x1+x2) Cu x1 Y x2 O 4   [Chemical Formula 1]

wherein x1 and x2 are molar ratios of Cu and Y, respectively, and 0<x1≤0.9, and 0<x2≤0.5.

2. The interconnect for the solid oxide fuel cell of claim 1 , wherein the ceramic protective layer has a coefficient of thermal expansion in a range of 10.0×10 −6 K −1 to 13.0×10 −6 K −1 at 973 K.

3. The interconnect for the solid oxide fuel cell of claim 1 , wherein:
0≤ DC≤ 6%; and

DC =absolute value of [(a coefficient of thermal expansion of the conductive substrate at 973 K−a coefficient of thermal expansion of the ceramic protective layer at 973 K)/(the coefficient of thermal expansion of the ceramic protective layer at 973 K)]*100(%).

4. The interconnect for the solid oxide fuel cell of claim 1 , wherein the ceramic protective layer has a thickness in a range of 10 μm to 30 μm.

5. The interconnect for the solid oxide fuel cell of claim 1 , wherein the conductive substrate is a ferritic stainless steel (FSS) substrate.

6. A method for preparing the interconnect of claim 1 , the method comprising:
forming the ceramic protective layer on the first surface of the conductive substrate.

7. The method of claim 6 , wherein the forming of the ceramic protective layer comprises:
preparing a conductive oxide powder by mixing, milling, drying and calcining raw powders;
preparing a paste comprising the conductive oxide powder;
depositing the paste on the first surface of the conductive substrate to provide a paste containing conductive substrate; and
heat treating the paste containing conductive substrate.

8. The method of claim 7 , wherein the raw powders comprise: one or more selected from the group consisting of Y 2 O 3 and Y(NO 3 ) 3 ; and one or more selected from the group consisting of CuO and Cu(NO 3 ) 2 .

9. The method of claim 7 , further comprising, before the depositing of the paste, sand blasting the conductive substrate using metal particles.

10. The method of claim 7 , wherein the depositing of the paste is performed using a screen printing method.

11. A solid oxide fuel cell comprising:
a plurality of unit cells comprising a first unit cell and a second unit cell; and
an interconnect layer comprising the interconnect of claim 1 between the first and second unit cells,
wherein the first unit cell comprises a fuel electrode, an air electrode, and an electrolyte between the fuel electrode and the air electrode, and
wherein the interconnect layer adjoins the air electrode or the fuel electrode of the first unit cell.

12. The interconnect for the solid oxide fuel cell of claim 1 , wherein:
the ceramic protective layer comprises a first ceramic protective layer and a second ceramic protective layer;
the conductive substrate further comprises a second surface; and
the first and second ceramic protective layers are, respectively, on the first and second surfaces of the conductive substrate.

13. The interconnect for the solid oxide fuel cell of claim 1 , wherein 0.2≤x1≤0.5, and 0<x2≤0.3.

14. The interconnect for the solid oxide fuel cell of claim 13 , wherein x2 is 0.1.

15. The method of claim 6 , wherein:
the conductive substrate further comprises a second surface; and
forming the ceramic protective layer comprises forming a first ceramic protective layer and a second ceramic protective layer on, respectively, on the first and second surfaces of the conductive substrate.

16. The method of claim 7 , wherein:
mixing the raw powders comprises mixing the raw powders with a solvent; and
the solvent comprises one or more of water, isopropanol, toluene, ethanol, n-propanol, n-butyl acetate, ethylene glycol, butyl carbitol, and butyl carbitol acetate.

Assignees

• Lg Chemical Ltd
• Daegu Gyeongbuk Inst Science & Tech

Inventors

• Noh Tai Min
• Ryoo Changseok
• Kim Daehwan
• Lee Kang Taek
• Choi Kwangwook
• Park Kwangyeon
• Joh Dong Woo
• Thaheem Imdadullah

Classifications

• H01M8/0217 Primary

  Complex oxides, optionally doped, of the type AMO3, A being an alkaline earth metal or rare earth metal and M being a metal, e.g. perovskites · CPC title

• H01M8/021

  Alloys based on iron · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M8/0228 Primary

  in the form of layered or coated products · CPC title

• H01M8/2425

  High-temperature cells with solid electrolytes · CPC title