JP2002289223A - Solid polymer electrolyte film fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of a sealing function between a sealing member and a separator by outward movement of the sealing member caused by gas pressure. SOLUTION: In this solid polymer electrolyte film fuel cell 10, by catching, between separators 24 and 26, each sealing member 20 formed on a cell 12 provided with a fuel electrode 16 and an air electrode 18 disposed on one surface and the other surface of a solid polymer electrolyte film 14, respectively, and at the circumferential edge part 121 of the cell 12, a fuel gas passage 36 and an oxidizer gas passage 38 are formed on the one-surface side and the other- surface side of the electrolyte film 14, respectively. Projecting parts 241 and 261 formed integrally with the circumferential edge parts of the separators 24 and 26 are engaged with recessed parts 201 formed on the corresponding sealing members 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid polymer electrolyte membrane fuel cell, and more particularly to a cell having a fuel electrode and an air electrode provided on one surface and the other surface of a solid polymer electrolyte membrane, respectively. The present invention relates to a structure in which a seal member formed on an outer peripheral edge of the above is sandwiched between separators.

[0002]

2. Description of the Related Art Conventional solid polymer electrolyte membrane fuel cells,
For example, in the device disclosed in Japanese Patent Application Laid-Open No. 8-148169, a cell in which a fuel electrode and an air electrode are respectively disposed on one surface and the other surface of a solid polymer electrolyte membrane is sandwiched between separators. A fuel gas passage and an oxidizing gas passage are formed on one surface side and the other surface side of the electrolyte membrane, respectively. Further, the outer peripheral edge of the cell is sandwiched between a pair of sealing members, and by ensuring the sealing property between the two, gas leakage from the fuel gas passage and / or the oxidizing gas passage to the outside can be prevented. Is to be prevented.

[0003]

However, when the outer peripheral edge of the cell is sandwiched between a pair of sealing members to maintain the sealing property between the two, a high fastening load is required at the time of assembling, and the number of manufacturing steps is reduced. To increase. Further, when the elasticity of rubber as a raw material of the seal member deteriorates with time, the sealing property deteriorates, and when the pressure of the gas passing through the fuel gas passage and / or the oxidizing gas passage becomes high, the pair of seal members becomes outside. Direction, and the sealing performance between the outer peripheral portion of the cell and the pair of sealing members may be extremely deteriorated.

Therefore, an object of the present invention is to provide a solid polymer electrolyte membrane fuel cell free of such a problem.

[0005]

The first technical means taken to solve the above technical problem is to dispose a fuel electrode and an air electrode on one surface and the other surface of a solid polymer electrolyte membrane, respectively. The fuel cell passage and the oxidizing gas passage are formed on one surface side and the other surface side of the solid polymer electrolyte membrane, respectively, by sandwiching a cell to be formed and a sealing member formed at an outer peripheral portion of the cell between separators. In the solid polymer electrolyte membrane fuel cell to be formed, a projection integrally formed on an outer peripheral edge of the separator is engaged with a corresponding recess formed in the sealing member.

A second technical means taken to solve the above technical problem is a cell in which a fuel electrode and an air electrode are respectively disposed on one surface and the other surface of a solid polymer electrolyte membrane and the cell. A solid polymer in which a fuel gas passage and an oxidizing gas passage are formed on one surface side and the other surface side of the solid polymer electrolyte membrane, respectively, by sandwiching a seal member formed at an outer peripheral portion between the separators. In the electrolyte membrane fuel cell, a protrusion integrally formed with the seal member is elastically attached to the corresponding separator.

[0007]

According to the first technical means, even if the pressure of the gas passing through the fuel gas passage and / or the oxidizing gas passage increases and the seal member is pushed outward,
Since the projection integrally formed on the outer peripheral edge of the separator engages with the corresponding recess formed on the sealing member,
The sealing member is not pushed outward.
Thus, the sealing function of the sealing member is not impaired.

Further, according to the second technical means, the projection integrally formed on the seal member is elastically attached to the corresponding separator, so that the two members are contacted by line contact in addition to the surface pressure contact. Since the sealing is performed, the sealing function of the sealing member is further enhanced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, a solid polymer electrolyte membrane fuel cell 10 includes a cell 12. Thus, cell 12
The fuel electrode 16 and the air electrode 18 are provided on one surface and the other surface of the solid polymer electrolyte membrane 14, respectively. The area of the solid polymer electrolyte membrane 14 is the fuel electrode 16 and the air electrode 18.
When the two electrodes 16 and 18 sandwich the solid polymer electrolyte membrane 14 as described above, the outer peripheral edge 141 of the solid polymer electrolyte membrane 14 becomes the fuel electrode 16 and the air electrode 1.
8 has a structure protruding from the peripheral end. Peripheral edge 141 of solid polymer electrolyte membrane 14 of cell 12 thus configured
The electrode unit 22 is formed by integrally molding a seal member 20 made of an ethylene propylene rubber as an elastic body.

The electrode unit 22 is sandwiched between a separator 24 and a separator 26, and between the separator 26 and another separator 24. Upper separator 2
Numeral 4 sandwiches a seal member 28 made of ethylene propylene rubber which is an elastic body formed as a single body with another separator 26 and defines a cooling water passage 30. The lower separator 24 sandwiches a sealing member 28 made of ethylene propylene rubber, which is an elastic body formed as a single body with another separator 26, and defines a cooling water passage 30.

The sealing member 20 formed on the outer peripheral edge of the cell 12 described above is sandwiched between the separators, so that one surface side of the solid polymer electrolyte membrane 14 (the fuel electrode 1).
On the other hand, a fuel gas passage 36 and an oxidizing gas passage 38 are formed on the other side (the air electrode 18 side). The fuel gas passage 36 communicates with the fuel gas supply port 40 and the fuel gas discharge port 42. The oxidizing gas passage 38 is
The oxidizing gas supply port 44 and the oxidizing gas discharge port 46 communicate with each other. As can be clearly understood from FIG. 1, the oxidizing gas supply port 44 is provided at an outer peripheral portion of the separator 24 and at the separator 2.
6 and the outer peripheral portion 1 of the solid polymer electrolyte membrane 14
Oxidant gas introduction passage 48 and solid polymer electrolyte membrane 14 formed by penetrating one side of
Communicates with the oxidizing gas passage 38 via a groove 50 formed in the direction in which the outer peripheral edge 141 extends. Oxidant gas outlet 4
Reference numeral 6 denotes an oxidizing gas exhaust passage 52 formed by penetrating the outer peripheral edge of the separator 24, the outer peripheral edge of the separator 26, and the other side of the outer peripheral edge 141 of the solid polymer electrolyte membrane 14 in the overlapping direction. Grooves 54 engraved in the extending direction on the other side of the outer peripheral edge 141 of the polymer electrolyte membrane 14
Through the oxidizing gas passage 38.

The fuel gas passage 36 also has a fuel gas supply port 40 and a fuel gas discharge port 42 in a similar manner (not shown).
Communicate with Further, the cooling water passage 30 also communicates with the cooling water supply port 60 and the cooling water discharge port 58.

A bead-shaped projection 241/261 is integrally formed on the outer peripheral edge of the separator 24/26.
The bead-shaped protrusions 241/261 are engaged with the corresponding concave portions 201 formed in the seal member 20. Due to this concave-convex fitting, the relative displacement in the extending direction between the separator 24/26 and the cell 12 is regulated, and the gas pressure is increased to exert a force to move the seal member 20 outward. Even though, the position of the seal member 20 does not change, and the seal characteristics between the outer peripheral edge of the separator 24/26 and the seal member 20 do not change.

The oxidizing gas introduction passage 48 and the oxidizing gas exhaust passage 52 are located further inside the uneven fitting portion between the outer peripheral edge of the separator 24/26 and the seal member 20.
On the side, a bead-shaped protrusion 202 is integrally formed on the seal member 20 and is elastically attached to the separator 24/26. A pair of grooves 204 are formed in parallel with the extending direction of the bead-shaped protrusion 202, and when the gas pressure increases, the bead-shaped protrusion 202 is deformed outward, and as a result, the bead is deformed. Separator 24 /
The resilience to the ball 26 further increases. Thus, the sealing function between the outer peripheral edge of the separator 24/26 and the sealing member 20 is further enhanced.

[0016]

As described above, according to the present invention, the sealing member is not pushed outward due to an increase in gas pressure, and the sealing function of the sealing member is not impaired. Further, the sealing function of the sealing member with respect to the separator is further enhanced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a specific example of a main part of a solid polymer electrolyte membrane fuel cell according to the present invention.

FIG. 2 is a plan view of a separator used in the solid polymer electrolyte membrane fuel cell shown in FIG.

FIG. 3 is a plan view of a cell employed in the solid polymer electrolyte membrane fuel cell shown in FIG. 1, as viewed from a fuel gas passage side.

FIG. 4 is a plan view of a cell employed in the solid polymer electrolyte membrane fuel cell shown in FIG. 1, as viewed from the oxidizing gas passage side.

5 is a cross-sectional view of a structure in which a cell and a seal member adopted in the solid polymer electrolyte membrane fuel cell shown in FIG. 1 are integrated.

FIG. 6 is a cross-sectional view of a sealing member for a cooling water cell employed in the solid polymer electrolyte membrane fuel cell shown in FIG.

FIG. 7 is a cross-sectional view of a pair of separators sandwiching a cell used in the solid polymer electrolyte membrane fuel cell shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Cell 121 Outer periphery of cell 14 Solid polymer electrolyte membrane 20 Seal member 24 Separator 241 Projection 26 Separator 261 Projection

Claims (2)

[Claims] 1. A cell in which a fuel electrode and an air electrode are respectively disposed on one surface and the other surface of a solid polymer electrolyte membrane and a sealing member formed on an outer peripheral edge of the cell are sandwiched between separators. A solid polymer electrolyte membrane fuel cell in which a fuel gas passage and an oxidizing gas passage are formed on one surface side and the other surface side of the solid polymer electrolyte membrane, respectively, which are integrally formed on an outer peripheral edge of the separator; A projecting portion is engaged with a corresponding concave portion formed in the sealing member, wherein the polymer electrolyte membrane fuel cell is a solid polymer electrolyte membrane fuel cell. 2. A cell in which a fuel electrode and an air electrode are respectively disposed on one surface and the other surface of a solid polymer electrolyte membrane and a seal member formed on an outer peripheral portion of the cell are sandwiched between separators. In a solid polymer electrolyte membrane fuel cell in which a fuel gas passage and an oxidizing gas passage are formed on one surface side and the other surface side of the solid polymer electrolyte membrane, respectively, a projection integrally formed on the seal member has A solid polymer electrolyte membrane fuel cell which is elastically attached to the corresponding separator.