Fuel cell unit

Patent metadata

Field	Value
Publication number	US-2017162879-A1
Application number	US-201715441522-A
Country	US
Kind code	A1
Filing date	Feb 24, 2017
Priority date	Aug 27, 2014
Publication date	Jun 8, 2017
Grant date	—

Abstract

A solid oxide fuel cell stack has a surface from which via conductors for drawing a current are exposed. Collector plates are disposed on the surfaces of the fuel cell stack so that one main surface of the collector plates faces the via conductors. Fixing plates are fixed to the collector plates. Spacers are disposed between the fuel cell stack and the fixing plates. An adhesive fixes the fixing plates to the fuel cell stack through the spacers.

First claim

1 . A fuel cell unit comprising:
a solid oxide fuel cell stack including:
a plurality of stacked fuel cells each including a solid electrolyte layer, a fuel electrode layer and an air electrode layer stacked with the solid electrolyte layer interposed therebetween;
a first separator on the fuel electrode layer; and
a second separator on the air electrode layer,
each of the fuel cells defining a fuel electrode gas flow channel in fluid communication with the fuel electrode layer and an air electrode gas flow channel in fluid communication with the air electrode layer;
a first conductor extending to a first end face of the plurality of stacked fuel cells in a stacking direction and electrically connected to the fuel electrode layer; and
a second conductor extending to a second end face of the plurality of stacked fuel cells in the stacking direction and electrically connected to the air electrode layer;
a first collector plate electrically connected to the first conductor and disposed on the first surface of the fuel cell stack; a second collector plate electrically connected to the second conductor and disposed on the second surface of the fuel cell stack; a first fixing plate disposed on the first collector plate; a second fixing plate disposed on the second collector plate; a first spacer disposed between the fuel cell stack and the first fixing plate; a second spacer disposed between the fuel cell stack and the second fixing plate; and an adhesive that secures at least one of the first fixing plate to the first spacer and the first spacer to the first surface of the fuel cell stack, and that secures at least one of the second fixing plate to the second spacer and the second spacer to the second surface of the fuel cell stack.

2 . The fuel cell unit according to claim 1 , wherein
the adhesive secures both of the first fixing plate to the first spacer and the first spacer to the first surface of the fuel cell stack, and secures both of the second fixing plate to the second spacer and the second spacer to the second surface of the fuel cell stack.

3 . The fuel cell unit according to claim 1 , wherein
the first spacer is integrally formed with the first fixing plate, the second spacer is integrally formed with the second fixing plate, and the adhesive is disposed between the first spacer and the first surface of the fuel cell stack, and is disposed between the second spacer and the second surface of the fuel cell stack.

4 . The fuel cell unit according to claim 1 , wherein
the first spacer is integrally formed with the first surface of the fuel cell stack, the second spacer is integrally formed with the second surface of the fuel cell stack, and the adhesive is disposed between first spacer and the first fixing plate, and is disposed between the second spacer and the second fixing plate.

5 . The fuel cell unit according to claim 1 , wherein each of the first fixing plate and the first spacer has a thermal expansion coefficient equal to a thermal expansion coefficient of the first separator.

6 . The fuel cell unit according to claim 5 , wherein each of the second fixing plate and the second spacer has a thermal expansion coefficient equal to a thermal expansion coefficient of the second separator.

7 . The fuel cell unit according to claim 1 , wherein each of the second fixing plate and the second spacer has a thermal expansion coefficient equal to a thermal expansion coefficient of the second separator.

8 . The fuel cell unit according to claim 1 , further comprising a conductive material disposed between the first surface of the fuel cell stack and the first collector plate, and disposed between the second surface of the fuel cell stack and the second collector plate.

9 . The fuel cell unit according to claim 8 , wherein the conductive material has a structure that is deformable in response to a thermal stress generated between the fuel cell stack and the first and second collector plates.

10 . The fuel cell unit according to claim 1 , wherein a difference between a first thermal expansion coefficient of the first and second collector plates and a second thermal expansion coefficient of each of the first and second separators, the first and second fixing plates, and the first and second spacers is 2 ppm/° C. or less.

11 . The fuel cell unit according to claim 1 , wherein the first and second fixing plates, the first and second spacers, and the first and second spacers are made of yttria-stabilized zirconia, and the first and second collector plates are made of ferritic stainless steel.

12 . The fuel cell unit according to claim 1 , wherein the adhesive is made of crystallized glass.

13 . The fuel cell unit according to claim 1 , wherein the first and second conductors are each divided into four respective sections.

14 . The fuel cell unit according to claim 13 , wherein the first collector plate and the second collector plate are each divided into four respective sections,
each of the four sections of the first collector plate being electrically connected to a respective one of the four sections of the first conductor, and each of the four sections of the second collector plate being electrically connected to a respective one of the four sections of the second conductor.

15 . The fuel cell unit according to claim 14 , wherein each of the first and second spacers have a cross shape,
the first spacer extending between the four respective sections of the first collector plate, and the second spacer extending between the four respective sections of the second collector plate.

Assignees

• Murata Manufacturing Co
• Tokyo Gas Co Ltd

Inventors

• Tomoshige Yosuke
• Hirai Tomoaki
• Sayo Yasuhiro
• Ito Takuya
• Kushi Takuto
• Hatae Toru

Classifications

• H01M8/0258

  characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant · CPC title

• H01M8/0228 Primary

  in the form of layered or coated products · CPC title

• H01M8/1246

  the electrolyte consisting of oxides · CPC title

• H01M8/021

  Alloys based on iron · CPC title

• H01M8/2425

  High-temperature cells with solid electrolytes · CPC title