Fuel cell

Patent metadata

Field	Value
Publication number	US-9954232-B2
Application number	US-201313875482-A
Country	US
Kind code	B2
Filing date	May 2, 2013
Priority date	Oct 5, 2011
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

Provided is a fuel cell as a fired body including a porous plate-like support substrate having a gas flow path formed therein, and a power generation element part provided on a principal surface of the support substrate, the power generation element part including at least a fuel electrode, a solid electrolyte, and an air electrode laminated in this order. The generation of cracks in the support substrate has a strong correlation with a “surface roughness of a wall surface of a gas flow” of the fuel cell in a state of a reductant. When the surface roughness of the wall surface of the gas flow path is 0.16 to 5.2 in terms of an arithmetic average roughness Ra in a state in which the fuel cell is a reductant that has been subjected to heat treatment in a reducing atmosphere, the generation of the cracks can be suppressed.

First claim

What is claimed is:

1. A solid oxide fuel cell as a fired body, the solid oxide fuel cell comprising:
a porous planar support substrate including a plurality of gas flow paths formed therein; and
a power generation element part provided on a surface of the porous planar support substrate, the power generation element part including at least a fuel electrode, a solid electrolyte, and an air electrode laminated in the stated order,
wherein the porous planar support substrate has a longitudinal direction, and the plurality of gas flow paths are through-holes formed parallel to each other at intervals in a width direction that extend in the longitudinal direction in the porous planar support substrate,
wherein an outer periphery of the porous planar support substrate is covered with a dense film of the solid electrolyte, and
wherein, in a state in which the fuel cell is a reductant that has been subjected to heat treatment in a reducing atmosphere, a surface roughness of a surface formed of a material for the porous planar support substrate in an inner wall portion of each of the plurality of gas flow paths is 0.16 μm to 5.2 μm in terms of an arithmetic average roughness Ra.

2. A solid oxide fuel cell according to claim 1 , wherein the porous planar support substrate has a porosity of 20% to 60%.

3. A solid oxide fuel cell according to claim 1 , wherein an aspect ratio that is a ratio of a width of the porous planar support substrate with respect to a thickness of the porous planar support substrate is 5 or more.

4. A solid oxide fuel cell according to claim 1 , wherein the porous planar support substrate contains one of a nickel oxide (NiO) and nickel (Ni), and an insulating ceramics.

5. A solid oxide fuel cell as a fired body, the solid oxide fuel cell comprising:
a porous planar support substrate having a plurality of gas flow paths formed therein;
a plurality of power generation element parts respectively provided in a plurality of portions away from each other on a principal surface of the porous planar support substrate, the plurality of power generation element parts each including at least a fuel electrode, a solid electrolyte, and an air electrode laminated in the stated order; and
at least one electrical connecting portion provided respectively between at least one set of adjacent power generation element parts, for electrically connecting the fuel electrode of one of the adjacent power generation element parts to the air electrode of another of the adjacent power generation element parts,
wherein concave portions each having a bottom wall and a side wall closed in a circumferential direction are respectively formed in the plurality of portions on the principal surface of the porous planar support substrate,
wherein the fuel electrode of corresponding one of the plurality of power generation element parts is buried in each of the concave portions,
wherein the porous planar support substrate has a longitudinal direction, and the plurality of gas flow paths are through-holes formed parallel to each other at intervals in a width direction that extend in the longitudinal direction in the porous planar support substrate,
wherein an outer periphery of the porous planar support substrate is covered with a dense film of the solid electrolyte, and
wherein, in a state in which the fuel cell is a reductant that has been subjected to heat treatment in a reducing atmosphere, a surface roughness of a surface formed of a material for the porous planar support substrate in an inner wall portion of each of the plurality of gas flow paths is 0.15 μm to 5.1 μm in terms of an arithmetic average roughness Ra.

6. A solid oxide fuel cell as a fired body, the solid oxide fuel cell comprising:
a porous planar support substrate having a plurality of gas flow paths formed therein;
a plurality of power generation element parts respectively provided in a plurality of portions away from each other on a principal surface of the porous planar support substrate, the plurality of power generation element parts each including at least a fuel electrode, a solid electrolyte, and an air electrode laminated in the stated order; and
at least one electrical connecting portion provided respectively between at least one set of adjacent power generation element parts, for electrically connecting the fuel electrode of one of the adjacent power generation element parts to the air electrode of another of the adjacent power generation element parts,
wherein each of the plurality of electrical connecting portions includes a first portion made of a dense material and a second portion connected to the first portion and made of a porous material,
wherein first concave portions each having a bottom wall made of a material for the porous planar support substrate and a side wall closed in a circumferential direction and made of the material for the porous planar support substrate around an entire periphery are respectively formed in the plurality of portions on the principal surface of the porous planar support substrate,
wherein the fuel electrode of corresponding one of the plurality of power generation element parts is buried in each of the first concave portions,
wherein second concave portions each having a bottom wall made of a material for the fuel electrode and a side wall closed in a circumferential direction and made of the material for the fuel electrode are respectively formed on outer surfaces of the buried fuel electrodes,
wherein the first portion of corresponding one of the at least one electrical connecting portion is buried in each of the second concave portions,
wherein the porous planar support substrate has a longitudinal direction, and the plurality of gas flow paths are through-holes formed parallel to each other at intervals in a width direction that extend in the longitudinal direction in the porous planar support substrate,
wherein an outer periphery of the porous planar support substrate is covered with a dense film of the solid electrolyte, and
wherein, in a state in which the fuel cell is a reductant that has been subjected to heat treatment in a reducing atmosphere, a surface roughness of a surface formed of a material for the porous planar support substrate in an inner wall portion of each of the plurality of gas flow paths is 0.15 μm to 5.1 μm in terms of an arithmetic average roughness Ra.

7. A solid oxide fuel cell according to claim 1 , wherein, in a sectional shape of each of the plurality of gas flow paths, a ratio of a length in the width direction of the porous planar support substrate with respect to a length in a thickness direction of the porous plate-like support substrate is 1.1 or more.

8. A solid oxide fuel cell according to claim 1 , wherein, in the state in which the fuel cell is the reductant that has been subjected to the heat treatment in the reducing atmosphere, the porous planar support substrate contains nickel (Ni) and a nickel oxide (NiO).

Assignees

• Ngk Insulators Ltd

Inventors

• Okamoto Taku
• Ohmori Makoto

Classifications

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M8/2432

  Grouping of unit cells of planar configuration · CPC title

• H01M8/1226

  characterised by the supporting layer · CPC title

• H01M8/0247 Primary

  characterised by the form (characterised by a channel configuration H01M8/0258) · CPC title

• H01M8/2428

  Grouping by arranging unit cells on a surface of any form, e.g. planar or tubular · CPC title