WO2010084799A1

WO2010084799A1 - Fuel cell

Info

Publication number: WO2010084799A1
Application number: PCT/JP2010/050204
Authority: WO
Inventors: 大介渡邉; 雄一佐藤; 信保根岸; 元太大道; 公一川村
Original assignee: 株式会社東芝
Priority date: 2009-01-20
Filing date: 2010-01-12
Publication date: 2010-07-29
Also published as: TW201044675A; JP2010170733A

Abstract

Disclosed is a fuel cell which is characterized by comprising: a membrane electrode assembly (2) which comprises an anode (13), a cathode (16) and an electrolyte membrane (17) interposed between the anode (13) and the cathode (16); a fuel supply mechanism (3) which is arranged on the anode side of the membrane electrode assembly and can supply a fuel to the anode; a cover plate (21) which is arranged on the cathode side of the membrane electrode assembly and is engaged in the fuel supply mechanism by a bending processing; and a stiff member (40) which is arranged between the membrane electrode assembly and the cover plate and has a higher stiffness than that of the cover plate.

Description

Fuel cell

This invention relates to a technology of a fuel cell using liquid fuel.

In recent years, attempts have been made to use a fuel cell as a power source for portable electronic devices such as notebook computers and mobile phones so that they can be used without charging for a long time. A fuel cell is characterized in that it can generate electric power simply by supplying fuel and air (particularly oxygen), and can generate electric power continuously for a long time by replenishing the fuel. For this reason, the fuel cell can be a very advantageous system as a power source for portable electronic devices due to the miniaturization.

In particular, a direct methanol fuel cell using methanol as a fuel (hereinafter sometimes referred to as DMFC) can be miniaturized and can be easily handled, so it is promising as a power source for portable electronic devices. Has been.

For example, according to Patent Document 1, a membrane electrode assembly is stacked on a flange portion of a fuel storage unit, a metal cover plate is attached from the air electrode side of the membrane electrode assembly, and a peripheral portion of the cover plate is attached to the membrane electrode assembly. The fuel container is fixed to the membrane electrode assembly by bending it along the outer periphery, the outer periphery of the flange portion, and the periphery of the back surface, and sandwiching the membrane electrode assembly and the flange portion with the periphery of the cover plate. Proposed.

Further, according to Patent Document 2, a structure is disclosed in which a structure in which an end portion of a cover plate is bent and crimped to a fuel supply portion and a structure in which the cover plate and the fuel supply portion are fastened and fixed are disclosed.

Furthermore, according to Patent Document 3, a configuration including a fuel electrode support plate and a front cover as a pressing plate for pressing the current collector against the membrane electrode assembly is disclosed.

In a fuel cell, in order to maintain power generation performance, a plurality of stacked DMFC components need to be fixed in a state where they are uniformly and moderately pressurized over the entire surface.

Securing methods include screwing or rivet joints. When these methods are applied, it is necessary to secure a through-hole through which the screws pass. For this reason, it is not desirable to apply these methods over the entire circumference of the fuel cell from the viewpoint of volume efficiency and assembly work efficiency. On the other hand, the method of fastening the plate material by bending is suitable for both volumetric efficiency and work efficiency. However, the plate material that can be bent has low rigidity. For this reason, the bending which swells in the direction away from the membrane electrode assembly is likely to occur, the pressurization becomes insufficient and the pressure becomes non-uniform in the surface, and the power generation performance may be deteriorated.

International Publication No. 2006/120966 Pamphlet JP 2008-218054 A JP 2008-226486 A

An object of the present invention is to provide a fuel cell that enables uniform pressurization of a membrane electrode assembly, improves workability, and provides a stable and sufficient output.

According to one aspect of the invention,
A membrane electrode assembly having an electrolyte membrane sandwiched between an anode and a cathode; a fuel supply mechanism disposed on the anode side of the membrane electrode assembly for supplying fuel toward the anode; and the membrane electrode junction A cover plate disposed on the cathode side of the body and fastened to the fuel supply mechanism by bending, a rigid member having a rigidity higher than that of the cover plate, disposed between the membrane electrode assembly and the cover plate; A fuel cell comprising: is provided.

According to the present invention, it is possible to provide a fuel cell that enables uniform pressurization of a membrane electrode assembly and improves workability, and can stably obtain a sufficient output.

FIG. 1 is a plan view showing the appearance of the cathode side of a fuel cell according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a cross-sectional structure of the fuel cell shown in FIG. 1 cut along a first direction. FIG. 3 is a diagram schematically showing a cross-sectional structure of the fuel cell shown in FIG. 1 cut along the second direction. FIG. 4 is a perspective view showing an appearance of a container constituting a fuel supply unit applicable to the fuel cell shown in FIG. FIG. 5 is a schematic cross-sectional view of the fuel cell of the example. FIG. 6 is a schematic cross-sectional view of the fuel cell of Comparative Example 1. FIG. 7 is a schematic cross-sectional view of a fuel cell of Comparative Example 2.

Hereinafter, a fuel cell according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing the appearance of the cathode side of a fuel cell (DMFC) 1 according to this embodiment.

The fuel cell 1 is formed in a rectangular flat plate shape. In the plan view shown in FIG. 1, the fuel cell 1 has a rectangular shape, a pair of long sides L1 and long sides L2 extending along the first direction X, and a second direction Y orthogonal to the first direction X. It has a pair of short side S1 and short side S2 extended along.

Further, a cover plate 21 is disposed on the cathode side surface of the fuel cell 1. The cover plate 21 has a substantially rectangular appearance, and is made of, for example, stainless steel (SUS). The cover plate 21 is formed with openings 21 A that are a plurality of through-holes that mainly allow air that is an oxidant to be taken in. The + mark in the figure shows an example of a position where the cover plate 21 is screwed or a rivet joint is applied.

2 is a view showing a cross section of the fuel cell 1 shown in FIG. 1 cut along the first direction X. FIG. 3 is a view showing the fuel cell 1 shown in FIG. 1 cut along the second direction Y. FIG.

The fuel cell 1 includes a membrane electrode assembly (hereinafter also referred to as MEA) 2 that constitutes an electromotive unit, and a fuel supply mechanism 3 that supplies fuel to the membrane electrode assembly 2.

That is, the membrane electrode assembly 2 includes an anode 13 (also referred to as a fuel electrode) in which an anode catalyst layer 11 and an anode gas diffusion layer 12 are laminated, a cathode catalyst layer 14 and a cathode gas diffusion layer 15. A proton (hydrogen ion) conductive electrolyte sandwiched between the laminated cathode (or may be referred to as an air electrode or an oxidant electrode) 16, the anode catalyst layer 11 of the anode 13, and the cathode catalyst layer 14 of the cathode 16. And a film 17. Such a membrane electrode assembly 2 is sandwiched between current collectors 18.

In this embodiment, as shown in FIG. 3, the membrane electrode assembly 2 includes a plurality of anodes 13 disposed on one surface 17A of a single electrolyte membrane 17 at intervals, and an electrolyte membrane. 17 has a plurality of cathodes 16 spaced apart from each of the anodes 13 on the other surface 17B.

Each combination of the anode 13 and the cathode 16 sandwiches the electrolyte membrane 17 to constitute a single cell. Here, each of the single cells extends along the first direction X and is arranged side by side in the second direction Y on the same plane. The structure of the membrane electrode assembly 2 is not limited to this example, and may be another structure.

In the example shown here, the membrane electrode assembly 2 is disposed on the four surfaces 131 to 134 disposed on one surface 17A of the single electrolyte membrane 17 and on the other surface 17B of the electrolyte membrane 17. The four cathodes 161 to 164 are provided. The anode 131 and the cathode 161 are arranged so as to face each other, and constitute a set of single cells. Similarly, the anode 132 and the cathode 162 are arranged so as to face each other, the anode 133 and the cathode 163 are arranged so as to face each other, and the anode 134 and the cathode 164 are arranged so as to face each other. Four sets of single cells are arranged on the same plane. Each single cell is electrically connected in series by a current collector 18.

The anode current collector A1 of the current collector 18 is laminated on the anode gas diffusion layer 12 of the anode 131. Similarly, the anode current collector A2 is laminated on the anode gas diffusion layer 12 of the anode 132, and the anode current collector A3 is The anode current diffusion layer 12 is stacked on the anode gas diffusion layer 12 of the anode 133, and the anode current collector A 4 is stacked on the anode gas diffusion layer 12 of the anode 134.

The cathode current collector C of the current collector 18 is laminated on the cathode gas diffusion layer 15 of the cathode 161. Similarly, the cathode current collector C2 is laminated on the cathode gas diffusion layer 15 of the cathode 162, and the cathode current collector C3 is The cathode current diffusion layer 15 of the cathode 163 is stacked, and the cathode current collector C4 is stacked on the cathode gas diffusion layer 15 of the cathode 164.

The membrane electrode assembly 2 is sealed by a seal member 19 such as a rubber O-ring disposed on the anode side and the cathode side of the electrolyte membrane 17. Thereby, fuel leakage and oxidant leakage from the membrane electrode assembly 2 are prevented.

A plate-like body 20 made of an insulating material is disposed on the cathode 16 side of the membrane electrode assembly 2. This plate-like body 20 mainly functions as a moisture retaining layer. That is, the plate-like body 20 is impregnated with a part of the water generated in the cathode catalyst layer 14 to suppress the transpiration of water, adjusts the amount of air taken into the cathode catalyst layer 14 and makes the air uniform. Promotes diffusion.

The fuel supply mechanism 3 is disposed on the anode 13 side of the membrane electrode assembly 2 described above. That is, the membrane electrode assembly 2 is disposed between the fuel supply mechanism 3 disposed on the anode side and the cover plate 21 disposed on the cathode side.

The fuel supply mechanism 3 is configured to supply fuel to the anode 13 of the membrane electrode assembly 2, but is not particularly limited to a specific configuration. Hereinafter, an example of the fuel supply mechanism 3 will be described.

The fuel supply mechanism 3 includes a fuel supply unit 3X that supplies fuel while dispersing and diffusing fuel in the direction of the surface of the anode 13 of the membrane electrode assembly 2 facing each other. The fuel supply unit 3X includes a container 30 formed in a box shape and a fuel distribution plate 31 disposed on the bottom surface 35 of the container 30. Such a fuel supply mechanism 3 is connected via a flow path 5 to a fuel storage portion 4 that stores liquid fuel.

The container 30 will be described in detail later, but a fuel inlet 30A for introducing fuel is formed in the side wall 36A. The fuel introduction port 30 A is connected to a flow path 5 connected to the fuel storage unit 4.

The fuel distribution plate 31 has one fuel inlet 32 and a plurality of fuel outlets 33, and connects the fuel inlet 32 and each fuel outlet 33 via a fuel passage such as a narrow tube 34. This is the configuration. The fuel inlet 32 is directly connected to the fuel inlet 30A, but may be connected via another fuel passage. The fuel discharge port 33 faces the anode 13 of the membrane electrode assembly 2.

The liquid storage unit 4 stores liquid fuel corresponding to the membrane electrode assembly 2. Examples of the liquid fuel include methanol fuels such as aqueous methanol solutions of various concentrations and pure methanol. The liquid fuel is not necessarily limited to methanol fuel. The liquid fuel may be, for example, an ethanol fuel such as an ethanol aqueous solution or pure ethanol, a propanol fuel such as a propanol aqueous solution or pure propanol, a glycol fuel such as a glycol aqueous solution or pure glycol, dimethyl ether, formic acid, or other liquid fuel. In any case, liquid fuel corresponding to the membrane electrode assembly 2 is stored in the fuel storage portion 4.

Furthermore, in the fuel supply mechanism 3, the pump 6 may be interposed in the flow path 5 connected to the fuel storage unit 4 or in the fuel passage between the fuel introduction port 30 A and the fuel injection port 32. The pump 6 is not a circulation pump that circulates fuel, but is a fuel supply pump that sends liquid fuel from the fuel storage unit 4 to the fuel supply unit 3X. The fuel supplied from the fuel supply unit 3X to the membrane electrode assembly 2 is used for the power generation reaction and is not circulated thereafter and returned to the fuel storage unit 4.

The type of the pump 6 is not particularly limited, but a pump that can feed a small amount of liquid fuel with good controllability and can be reduced in size and weight is preferable.

The fuel cell 1 of this embodiment is different from the conventional active method because it does not circulate the fuel, and does not impair the downsizing of the device. Further, the pump 6 is used to supply the liquid fuel, which is different from a pure passive system such as a conventional internal vaporization type. The fuel cell 1 shown in FIG. 1 employs a system called a semi-passive type, for example.

In the fuel supply mechanism 3, a fuel cutoff valve may be arranged in series with the pump 6. Further, a balance valve that balances the pressure in the fuel storage unit 4 with the outside air may be attached to the fuel storage unit 4 and the flow path 5.

As described above, the fuel discharged from the fuel supply unit 3X is supplied to the anode 13 of the membrane electrode assembly 2. In the membrane electrode assembly 2, the fuel diffuses through the anode gas diffusion layer 12 and is supplied to the anode catalyst layer 11. When methanol fuel is used as the liquid fuel, an internal reforming reaction of methanol shown in the following formula (1) occurs in the anode catalyst layer 11. When pure methanol is used as the methanol fuel, the water generated in the cathode catalyst layer 14 or the water in the electrolyte membrane 17 is reacted with methanol to cause the internal reforming reaction of the formula (1). Alternatively, the internal reforming reaction is caused by another reaction mechanism that does not require water.

CH ₃ OH + H ₂ O → CO ₂ + 6H ⁺ + 6e ⁻ (1)
The electrons (e ⁻ ) generated by this reaction are guided to the outside via the current collector 18, and after operating a portable electronic device or the like as so-called electricity, the electrons (e ⁻ ) are passed to the cathode 16 via the current collector 18. Led. Proton (H ⁺ ) generated by the internal reforming reaction of the formula (1) is guided to the cathode 16 through the electrolyte membrane 17. Air is supplied to the cathode 16 as an oxidant. Electrons (e ⁻ ) and protons (H ⁺ ) reaching the cathode 16 react with oxygen in the air in the cathode catalyst layer 14 in accordance with the following equation (2), and water is generated along with this reaction.

6e ⁻ + 6H ⁺ + (3/2) O ₂ → 3H ₂ O (2)
In the power generation reaction of the fuel cell 1 described above, in order to increase the power to be generated, the catalytic reaction is smoothly performed, and the fuel is uniformly supplied to the entire electrode of the membrane electrode assembly 2 so that the entire electrode becomes more effective. It is important to contribute to power generation.

FIG. 4 is a perspective view showing an appearance of the container 30 constituting the fuel supply unit 3X. The container 30 has a rectangular bottom surface 35 that is long in the first direction X, and side walls 36A to 36D that rise from four sides of the bottom surface 35. More specifically, the side wall 36 A extends along the short side S 1 of the fuel cell 1. The side wall 36 B extends along the short side S 2 of the fuel cell 1. The side wall 36 C extends along the long side L 1 of the fuel cell 1. The side wall 36 D extends along the long side L 2 of the fuel cell 1. The side walls 36A to 36D have substantially the same height.

A fuel inlet 30A is formed at substantially the center of the side surface of the side wall 36A (that is, near the middle point of the short side S1). In the example shown in FIG. 4, the side wall 36A is formed with a plurality of through holes H1 penetrating in the height direction. These through holes H1 are formed so as to avoid the fuel inlet 30A. The fuel introduction port 30A is connected to a flow path connected to the fuel storage unit.

A plurality of through holes H2 penetrating in the height direction are formed in the side wall 36B. The side wall 36C and the side wall 36D are formed to have a smaller width than the side wall 36A and the side wall 36B, and no through hole is formed.

Such a container 30 is formed by molding using, for example, a resin material.

In this embodiment, as shown in FIGS. 2 and 3, the fuel cell 1 includes a rigid member 40 disposed between the membrane electrode assembly 2 and the cover plate 21. The rigid member 40 has higher rigidity than the cover plate 21. Such a rigid member 40 is formed in a flat plate shape, for example, and is overlaid on the plate-like body 20 disposed on the membrane electrode assembly 2. In addition, the peripheral portion of the rigid member 40 overlaps each of the side walls 36 A to 36 D of the container 30. That is, the rigid member 40 holds the membrane electrode assembly 2 with the fuel supply mechanism 3.

The cover plate 21 overlaps the rigid member 40 that holds the membrane electrode assembly 2 between the cover plate 21 and the fuel supply mechanism 3 including the container 30 described above, and is fastened to the fuel supply mechanism 3. In particular, in order to reduce the size of the fuel cell 1 or improve the assembling workability, the cover plate 21 has a fuel supply mechanism by bending (caulking) at least one side of the fuel cell 1 or two opposite sides. It is desirable to be fastened with 3.

When the container 30 shown in FIG. 4 is applied, the cover plate 21 is fastened to the container 30 constituting the fuel supply mechanism 3 by bending at the long side L1 and the long side L2 of the fuel cell 1. That is, the end portions of the cover plate 21 along the long side L1 and the long side L2 are bent along the outer periphery of the membrane electrode assembly 2, the side wall 36C and the side wall 36D of the container 30, respectively. Can be folded.

Also, at the short side S1 and the short side S2, the cover plate 21 is fastened to the container 30 by a method such as screwing or a rivet joint. That is, the end portions of the cover plate 21 along the short side S1 and the short side S2 are overlapped with the side wall 36A and the side wall 36B of the container 30, respectively, and are fastened by screwing or rivet joints using the through holes H1 and H2. Has been. The rigid member 40 also has through-holes communicating with the through-holes H1 and H2 at positions overlapping the

side walls

36A and 36B of the container 30, respectively, and is fixed to the container 30 together with the cover plate 21 by screwing or rivet joints. It is concluded.

According to such a configuration, the cover plate 21 is formed using a material having relatively low rigidity, that is, a material that can be easily bent, and the rigid member 40 is formed using a material having higher rigidity than the cover plate 21. Yes. Then, the cover plate 21 is attached so as to cover the rigid member 40 with the rigid member 40 holding a plurality of DMFC components stacked between the fuel supply mechanism 3 and the end of the cover plate 21 is bent. The fuel supply mechanism 3 is fastened by processing.

Thereby, the rigid member 40 is appropriately pressurized by the cover plate 21. For this reason, the rigid member 40 pressurizes the DMFC components including the membrane electrode assembly 2 over the entire surface with a uniform and appropriate pressure. Since the cover plate 21 is fastened to the fuel supply mechanism 3, the pressurized state by the rigid member 40 is maintained.

Therefore, it is possible to pressurize the membrane electrode assembly 2 uniformly and appropriately while improving the workability for fastening. For this reason, the fuel cell 1 which can obtain sufficient output stably can be provided. Even if the cover plate 21 is bent in the direction away from the rigid member 40 due to the bending process, the rigid member 40 can be used as long as the rigid member 40 is pressed on the periphery of the cover plate 21. The state where the membrane electrode assembly 2 is pressurized uniformly and appropriately can be maintained.

The cover plate 21 is desirably fastened to the container 30 at least on one side by bending, and the four sides of the fuel cell 1 may be fastened to the fuel supply mechanism 3 by bending.

Further, when the bending process is difficult, or when a fastening strength is required rather than the bending process, the cover plate 21 may be fastened to the container 30 at least on one side by screwing or a rivet joint. .

The rigid member 40 described above has an opening 40A which is a through hole communicating with the opening 21A of the cover plate 21. The openings 40A have substantially the same shape as the openings 21A and are formed at the same intervals.

According to such a configuration, the air permeability on the cathode side of the fuel cell 1 is ensured by the opening 40A of the rigid member 40 and the opening 21A of the cover plate 21. For this reason, uptake of oxygen necessary for power generation and discharge of gas generated along with power generation are not hindered, and it is possible to maintain an environment suitable for power generation of the fuel cell 1.

The fuel supply mechanism 3 described above is formed such that its rigidity is higher than that of the cover plate 21. Here, in the fuel supply mechanism 3, the overall rigidity of the fuel distribution plate 31 and the container 30 that sandwich the DMFC component including the membrane electrode assembly 2 between the rigid member 40 and the container 30 is higher than that of the cover plate 21. It is formed to be higher.

That is, for example, when the rigidity of the fuel distribution plate 31 and the container 30 is low, there is a risk that the fuel distribution plate 31 and the cover 30 are bent due to the fastening with the cover plate 21. In other words, the DMFC components including the membrane electrode assembly 2 need to be kept in close contact with each other, and are desirably sandwiched between a pair of members having relatively high rigidity. Therefore, it is desirable that not only the rigid member 40 but also the rigidity of the fuel supply mechanism 3 is higher than that of the cover plate 21.

The rigid member 40 described above is formed of a single plate material. Here, for example, the rigid member 40 is formed of relatively thick stainless steel (SUS), but is not limited thereto.

The rigid member 40 may be configured by stacking two or more plate materials. That is, even in a configuration in which a plurality of thin plate materials having relatively low rigidity are stacked, it is only necessary that the overall rigidity of the rigid member 40 is higher than that of the cover plate 21.

Note that the rigidity here is defined by the following method.

First, the end of the rigid member or the end of the cover plate is fixed, the central part of each plane is pressed down, and the load required to displace the central part by 1 mm is measured. It is determined that the rigidity is higher when the load required for the displacement of 1 mm is larger. Here, the “end portion” refers to a position from one end portion of the rigid member or the cover plate to a range corresponding to a distance of 10% or less of the distance between the one end portion and the other end portion in the planar direction. . Moreover, when the edge part of the cover plate is bent, let the bent part be an edge part.

As an example, when the cover plate 21 and the rigid member 40 are formed of the same material, for example, stainless steel (SUS), the rigidity increases as the thickness increases, so the rigid member 40 is formed thicker than the cover plate 21.

In order to ensure the rigidity necessary for the rigid member 40, the thickness of the rigid member 40 is desirably 0.5 mm or more. When the rigid member 40 having such a thickness is applied, the deformation of the rigid member 40 itself is suppressed regardless of the thickness and rigidity of the cover plate 21, and the DMFC component is pressurized with uniform and appropriate pressure in the surface. It becomes possible.

On the other hand, if the rigid member 40 is too thick, the weight of the fuel cell 1 increases and the thickness of the fuel cell 1 also increases. For this reason, it is desirable that the thickness of the rigid member 40 be 1.0 mm or less. In total, the thickness of the rigid member 40 is more preferably in the range of 0.6 mm to 0.8 mm.

(Example)
As an example, as shown in FIG. 5, the plate-like body 20 was disposed on the cathode 16 side of the membrane electrode assembly 2 accommodated in the container 30, and the rigid member 40 was further disposed on the plate-like body 20. The rigid member 40 is made of stainless steel and has a thickness of 0.7 mm.

The cover plate 21 was disposed so as to cover the rigid member 40 and the container 30. The cover plate 21 was fastened to the container 30 by bending. Such a cover plate 21 is made of stainless steel and has a thickness of 0.3 mm.

The rigidity of the used rigid member 40 and cover plate 21 was confirmed by the method described above. As a result, when the load required for displacing the central portion of the cover plate 21 by 1 mm was 1, the load required for displacing the central portion of the rigid member 40 by 1 mm was 4.

In such an embodiment, the cover plate 21 can be easily bent, and the membrane electrode assembly 2 can be uniformly pressed by the cover plate 21 and the rigid member 40 after the bending process.

As Comparative Example 1, as shown in FIG. 6, the plate-like body 20 is arranged on the cathode 16 side of the membrane electrode assembly 2 accommodated in the container 30, and the cover plate 21 is further arranged on the plate-like body 20. . The cover plate 21 is made of stainless steel and has a thickness of 1.0 mm. In addition, as a result of confirming the rigidity of the cover plate 21 by the described method, when the load required for displacing the central portion of the 0.3 mm thick cover plate used in the example by 1 mm is 1, a comparative example The load required for displacing the central portion of one cover plate 21 by 1 mm was 6.

In Comparative Example 1 as described above, although high rigidity was obtained, it was difficult to bend and the cover plate 21 and the container 30 could not be fastened. As a matter of course, the membrane electrode assembly 2 could not be uniformly pressurized.

As Comparative Example 2, as shown in FIG. 7, a plate-like body 20 is disposed on the cathode 16 side of the membrane electrode assembly 2 housed in a container 30, and the cover used in the example on this plate-like body 20. Plate 21 was placed. The cover plate 21 is made of stainless steel and has a thickness of 0.3 mm.

In Comparative Example 2 as described above, the bending process can be easily performed and the cover plate 21 and the container 30 can be fastened, but the rigidity of the cover plate 21 is insufficient, and the membrane electrode assembly is formed after the bending process. Bent in a direction away from 2. As a matter of course, the membrane electrode assembly 2 could not be uniformly pressurized.

As described above, according to this embodiment, a fuel cell that can uniformly pressurize a membrane electrode assembly and improve workability and stably obtain sufficient output is provided. it can.

The fuel cell 1 of the above-described embodiment is effective when various liquid fuels are used, and the type and concentration of the liquid fuel are not limited. However, the fuel supply unit 3X that supplies fuel while being dispersed in the plane direction is particularly effective when the fuel concentration is high. For this reason, the fuel cell 1 of the embodiment can exert its performance and effects particularly when methanol having a concentration of 80 wt% or more is used as the liquid fuel. Therefore, the embodiment is suitable for the fuel cell 1 using a methanol aqueous solution having a methanol concentration of 80 wt% or more or pure methanol as a liquid fuel.

Furthermore, although embodiment mentioned above demonstrated the case where this invention was applied to the semi-passive type fuel cell 1, this invention is not restricted to this, It is with respect to an internal vaporization type pure passive type fuel cell. Is applicable.

Note that the present invention can be applied to various fuel cells using liquid fuel. In addition, the specific configuration of the fuel cell, the supply state of the fuel, and the like are not particularly limited, and all of the fuel supplied to the MEA is liquid fuel vapor, all is liquid fuel, or part is liquid state. The present invention can be applied to various forms such as a vapor of supplied liquid fuel. In the implementation stage, the constituent elements can be modified and embodied without departing from the technical idea of the present invention. Furthermore, various modifications are possible, such as appropriately combining a plurality of constituent elements shown in the above embodiment, or deleting some constituent elements from all the constituent elements shown in the embodiment. Embodiments of the present invention can be expanded or modified within the scope of the technical idea of the present invention, and these expanded and modified embodiments are also included in the technical scope of the present invention.

Claims

A membrane electrode assembly having an electrolyte membrane sandwiched between an anode and a cathode;
A fuel supply mechanism disposed on the anode side of the membrane electrode assembly and supplying fuel toward the anode;
A cover plate disposed on the cathode side of the membrane electrode assembly and fastened to the fuel supply mechanism by bending;
A rigid member disposed between the membrane electrode assembly and the cover plate and having a rigidity higher than that of the cover plate;
A fuel cell comprising:
The fuel cell according to claim 1, wherein the rigidity of the fuel supply mechanism is higher than that of the cover plate.
2. The fuel cell according to claim 1, wherein the rigid member is formed of a single plate material.
2. The fuel cell according to claim 1, wherein the rigid member is formed by stacking two or more plate members.
2. The fuel cell according to claim 1, wherein the rigid member is made of the same material as the cover plate and is thicker than the cover plate.
2. The fuel cell according to claim 1, wherein the thickness of the rigid member is 0.5 mm or more.
2. The fuel cell according to claim 1, wherein the thickness of the rigid member is 1.0 mm or less.
The fuel supply mechanism includes a container formed in a box shape,
The fuel cell according to claim 1, wherein the cover plate is fastened to the container at least on one side by bending.
The fuel cell according to claim 8, wherein the cover plate is fastened to the container at least on one side by screwing or a rivet joint.
2. The fuel cell according to claim 1, wherein the rigid member and the cover plate have through holes communicating with each other.