Interconnects for solid oxide fuel cell comprising nano-sized oxide dispersion in ferritic stainless steel and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-12300866-B2
Application number	US-202117563945-A
Country	US
Kind code	B2
Filing date	Dec 28, 2021
Priority date	Dec 29, 2020
Publication date	May 13, 2025
Grant date	May 13, 2025

Abstract

Provided is an interconnect for a solid oxide fuel cell including ferritic stainless steel dispersed with nano-CeO2 and Nb2O5. The interconnect for the solid oxide fuel cell of the present disclosure includes nano-CeO2 and Nb2O5 having specific particle sizes in specific contents, thereby suppressing the formation of the insulating layer SiO2 and exhibiting an excellent improvement effect of high-temperature characteristics such as oxidation resistance and sheet resistance.

First claim

What is claimed is:

1. An interconnect for a solid oxide fuel cell comprising ferritic stainless steel dispersed with nano-CeO 2 and Nb 2 O 5 ,
wherein a particle size of the nano-CeO 2 is 20 nm or less,
wherein a particle size of the Nb 2 O 5 is 45 μm or less,
wherein a composition of the ferritic stainless steel is as follows:

Steel
Element Composition (wt. %)

alloy
Fe
Cr
O
S
N
C
Si
Mn

Balance
16.85
0.054
0.003
0.13
0.02
0.5
0.62

and wherein a content of the nano-CeO 2 is 3 wt. % and a content of the Nb 2 O 5 is 1 wt. %;
wherein said ferritic stainless steel is made by the following process:
obtaining alloy powder slurry by mixing nano-CeO 2 powder and Nb 2 O 5 powder with ferritic stainless steel powder and then using a high energy ball milling (HEBM) process of the mixed powder;
drying the slurry;
grinding and sieving the dried mixed powder;
pelletizing the ground and sieved powder by a uni-axial press;
obtaining a molded body by cold-isostatic pressing the pellets; and
obtaining an alloy-sintered body by sintering the molded body;
wherein the alloy-sintered body is said ferritic stainless steel; and
wherein in the alloy-sintered body, nano-CeO 2 and Nb 2 O 5 have a uniform distribution and form a microstructure.

2. The interconnect for the solid oxide fuel cell of claim 1 , wherein the interconnect forms a laves phase (Fe 2 Nb) under fuel cell operating conditions.

3. A solid oxide fuel cell comprising the interconnect for the solid oxide fuel cell of claim 1 .

4. A manufacturing method of an interconnect for a solid oxide fuel cell comprising steps of:
obtaining alloy powder slurry by mixing nano-CeO 2 powder and Nb 2 O 5 powder with ferritic stainless steel powder and then using a high energy ball milling (HEBM) process of the mixed powder;
drying the slurry;
grinding and sieving the dried mixed powder;
pelletizing the ground and sieved powder by a uni-axial press;
obtaining a molded body by cold-isostatic pressing the pellets; and
obtaining an alloy-sintered body by sintering the molded body,
wherein in the alloy-sintered body, nano-CeO 2 and Nb 2 O 5 have a uniform distribution and form a microstructure,
wherein a particle size of the nano-CeO 2 is 20 nm or less,
wherein a particle size of the Nb 2 O 5 is 45 μm or less,
wherein a composition of the ferritic stainless steel is as follows:

Steel
Element Composition (wt. %)

alloy
Fe
Cr
O
S
N
C
Si
Mn

Balance
16.85
0.054
0.003
0.13
0.02
0.5
0.62

and wherein a content of the nano-CeO 2 is 3 wt. % and a content of the Nb 2 O 5 is 1 wt. %.

5. The manufacturing method of the interconnect for the solid oxide fuel cell of claim 4 , wherein a particle size of the ferritic stainless steel powder is 10 to 50 μm.

6. The manufacturing method of the interconnect for the solid oxide fuel cell of claim 4 , wherein the high energy ball milling is performed at a rate of 200 rpm to 300 rpm.

Assignees

• Korea Inst Energy Res

Inventors

• Song Rak Hyun
• Kim Tae Hun
• Joh Dong Woo
• Lee Seung Bok
• Lim Tak Hyoung
• Kwon Beom Su
• Hussain Amjad

Classifications

• H01M8/021

  Alloys based on iron · CPC title

• B22F3/04

  by applying fluid pressure {, e.g. by cold isostatic pressing [CIP]} · CPC title

• B22F2301/35

  Iron · CPC title

• B22F2302/25

  Oxide · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title