Cell structure for fuel cell stack

Patent metadata

Field	Value
Publication number	US-10199663-B2
Application number	US-201414785533-A
Country	US
Kind code	B2
Filing date	Mar 24, 2014
Priority date	Apr 22, 2013
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A cell structure for a fuel cell stack that is formed by stacking unit cells C each including a membrane electrode assembly 1 and a pair of separators 2 holding the membrane electrode assembly 1 therebetween. The membrane electrode assembly 1 includes a frame 3 in the periphery having such a size as to extend outward over the edges of the separators 2. Communication holes 21, 22 in communication with the front and back sides are formed in the frame 3 in an area from a sealing part 11 between frames 3 adjacent in the cell stacking direction to a sealing parts 12 between the membrane electrode assembly 1 and the separators 2. The air in a space Q formed between the inner and outer sealing parts 11, 12 is allowed to be released to the outside through the communication holes 21, 22, and a breakage of the adhesive of the sealing parts 11, 12 is thereby prevented.

First claim

The invention claimed is:

1. A cell structure for a fuel cell stack that is formed by stacking unit cells each including a membrane electrode assembly and a pair of separators holding the membrane electrode assembly therebetween, wherein
the membrane electrode assembly comprises a frame in a periphery, the frame having such a size as to extend outward over edges of the separators,
first manifold holes configured to supply cathode gas are formed in corresponding positions of the separators and the frame, the first manifold holes being in communication in a cell stacking direction to form a first manifold;
second manifold holes configured to discharge cathode gas are formed in corresponding positions of the separators and the frame, the second manifold holes being in communication in the cell stacking direction to form a second manifold;
at least one communication hole in communication with front and back sides of the frame is formed in the frame in an area from a bonded part between frames adjacent in the cell stacking direction to a bonded part between the membrane electrode assembly and the separators adjacent in the cell stacking direction in an outer side of the first manifold holes and the second manifold holes with respect to the membrane electrode assembly;
the at least one communication hole is configured to allow air in a space between adjacent unit cells extending from the bonded part between frames adjacent in the cell stacking direction to the bonded part between the membrane electrode assembly and the separators adjacent in the cell stacking direction to be released to an outside of the space;
the unit cells have a double sealing structure that continues along an overall periphery and that is comprised of the bonded part between the frames adjacent in the cell stacking direction and the bonded part between the membrane electrode assembly and the separators adjacent in the cell stacking direction; and
the bonded part between the frames adjacent in the cell stacking direction and the bonded part between the membrane electrode assembly and the separators adjacent in the cell stacking direction are parallel to each other along the overall periphery.

2. The cell structure for the fuel cell stack according to claim 1 , wherein the at least one communication hole is formed in an area of the frame opposed to another frame adjacent in the cell stacking direction.

3. The cell structure for the fuel cell stack according to claim 1 , wherein the at least one communication hole is formed in an area of the frame opposed to the separators.

4. The cell structure for the fuel cell stack according to claim 1 , wherein another communication hole in communication with front and back sides of the separators is formed in the separators in an area from the bonded part between frames adjacent in the cell stacking direction to the bonded part between the membrane electrode assembly and the separators.

5. The cell structure for the fuel cell stack according to claim 1 , wherein the first manifold holes and the second manifold holes are provided within an area bounded by the bonded part between the membrane electrode assembly and the separators adjacent in the cell stacking direction.

6. The cell structure for the fuel cell stack according to claim 1 , wherein
the frame is rectangular and has four corners;
a plurality of communication holes in communication with the front and back sides of the frame are formed in the frame; and
at least one of the plurality of communication holes is provided in each of the four corners of the frame.

7. The cell structure for the fuel cell stack according to claim 1 , wherein
a plurality of communication holes in communication with the front and back sides of the frame are formed in the frame;
the plurality of communication holes includes an outer communication hole formed in an area of the frame opposed to an adjacent frame in the cell stacking direction and an inner communication hole formed in an area of the frame opposed to one of the separators in the cell stacking direction; and
the inner communication hole is closer to the membrane electrode assembly than the outer communication hole.

8. The cell structure for the fuel cell stack according to claim 1 , further comprising at least one additional communication hole formed in one of the separators, wherein
the at least one communication hole formed in the frame and the at least one additional communication hole formed in one of the separators are round in shape; and
the at least one additional communication hole formed in one of the separators is displaced by a radius relative to the at least one communication hole formed in the frame.

9. A cell structure for a fuel cell stack that is formed by stacking unit cells each including a membrane electrode assembly and a pair of separators holding the membrane electrode assembly therebetween, wherein
the membrane electrode assembly comprises a frame in a periphery, the frame having such a size as to extend outward over edges of the separators,
first manifold holes configured to supply cathode gas, second manifold holes configured to discharge cathode gas, third manifold holes configured to supply anode gas, fourth manifold holes configured to discharge anode gas, fifth manifold holes configured to supply cooling fluid, and sixth manifold holes configured to discharge cooling fluid are formed in corresponding positions of the separators and the frame, the first manifold holes being in communication in a cell stacking direction to form a first manifold, the second manifold holes being in communication in the cell stacking direction to form a second manifold, the third manifold holes being in communication in the cell stacking direction to form a third manifold, the fourth manifold holes being in communication in the cell stacking direction to form a fourth manifold, the fifth manifold holes being in communication in the cell stacking direction to form a fifth manifold, and the sixth manifold holes being in communication in the cell stacking direction to form a sixth manifold;
the fuel cell stack comprises an outer sealing part and an inner sealing part, wherein the first manifold holes, the second manifold holes, the third manifold holes, the fourth manifold holes, the fifth manifold holes, and the sixth manifold holes are provided in an interior of a region bound by the inner sealing part, and the inner sealing part is provided in an interior of a region bound by the outer sealing part and is parallel to the outer sealing part along an overall periphery,
adjacent frames in the cell stacking direction are bonded to each other through the outer sealing part, and the inner sealing part joins the membrane electrode assembly with the separators,
the unit cells have a double sealing structure that continues along the overall periphery and that is comprised of the outer and the inner sealing parts,
at least one communication hole in communication with front and back sides of the frame is formed in the frame between the outer sealing part and the inner sealing part, and
the at least one communication hole is configured to allow air in a space between adjacent unit cells extending from the outer sealing part to the inner sealing part to be released to an outside of the space.

10. The cell structure for the fuel cell stack according to claim 9 , wherein the at least one communication hole is formed in an area of the frame opposed to another frame adjacent in the cell stacking direction.

11. The cell structure for the fuel cell stack according to claim 9 , wherein the at least one communication hole is formed in an area of the frame opposed to the separators.

Assignees

• Nissan Motor

Inventors

• Kageyama Kazuhiro

Classifications

• H01M8/0276

  Sealing means characterised by their form (H01M8/0273 takes precedence) · CPC title

• H01M8/0273 Primary

  with sealing or supporting means in the form of a frame · CPC title

• H01M8/242

  comprising framed electrodes or intermediary frame-like gaskets (H01M8/2425, H01M8/244 take precedence) · CPC title

• H01M8/2465

  Details of groupings of fuel cells · CPC title

• H01M8/2483

  characterised by internal manifolds · CPC title