JP2005293880A - Fuel cell and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a unit-cell fuel battery which can be made thinner and a fuel battery of a compact stack structure laminating a plurality of unit cells, as well as a manufacturing method, capable of improving its power generating efficiency. <P>SOLUTION: A bag-like area is formed by making anode electrodes 4 face a pair of membrane electrode junctions 2, to which hydrogen is supplied. Therefore, hydrogen supply is possible only to the anode electrodes 4 in the bag-like region from a hydrogen inlet 12, dispensing with a special separator for separating from air supplied to a cathode electrode 5 side. Further, since the unit cells 7 can be formed of component members alone consisting of a film and a layer, the pair of the membrane electrode junction 2 overlapped will not become so thick. Therefore, the fuel battery 1 as a whole can be made thinner. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell including unit cells, a fuel cell having a stack structure in which a plurality of unit cells are stacked, and a method for manufacturing the same.

  A fuel cell continuously supplies fuel (hydrogen) and air (oxygen) to separate electrodes from the outside, and uses the catalyst contained in the electrodes to electrochemically react to generate electrical energy. It is something to take out. In recent years, environmental problems have become more prominent because of high efficiency and less carbon dioxide emissions than other power generation methods. Among fuel cells, a fuel cell using a polymer solid electrolyte membrane has an operating temperature close to room temperature, and can be reduced in thickness and size, and is expected to be applied to portable devices and the like.

  The electromotive force per unit cell of the fuel cell is determined by the type of electrochemical reaction, but it is as low as about 0.7 volts, so that it is necessary to improve the output in order to actually use it as a battery. In order to improve the output of the fuel cell, it is conceivable to increase the electromotive force and the capacity of the fuel cell as a whole. In order to increase the electromotive force, a method of stacking unit cells in series is well known. In order to increase the capacity, methods are known in which the electrode area and the geometric area of the reaction interface are increased or the output density per unit area is increased. However, these methods for improving the output of the fuel cell are contrary to the miniaturization of stacking unit cells and increasing the electrode area. For this reason, in the field of application to portable devices and the like that need to be miniaturized, a device is required for miniaturization.

In addition, when unit cells using polymer solid electrolyte membranes are stacked to improve the output of the fuel cell, the contact resistance between the components of the fuel cell also affects the power generation efficiency of the fuel cell. In order to improve the power generation efficiency, it is necessary to uniformly apply a load to the battery to reduce the contact resistance.
As an example of reducing the contact resistance, a fuel cell having a separator for separating the supply of fuel on the anode side and the supply of air on the cathode side is known to apply a load uniformly to the constituent members via the separator. (For example, refer to Patent Document 1).

JP 2000-315507 A (2nd to 3rd pages, FIG. 1)

  However, as in Patent Document 1, the method using a separator for preventing mixing of different gases requires rib processing for introducing gas to both sides of the separator. The structure of the rib is determined in consideration of the strength of the separator itself (the strength necessary to apply a load uniformly to the battery components), the supply efficiency of fuel and air to the electrode, or the prevention of mixing thereof, etc. It is difficult to reduce the thickness of the separator itself. Therefore, sandwiching the separator increases the thickness of the laminated structure itself, which makes it difficult to reduce the size of the fuel cell as a whole.

  A first object of the present invention is to provide a unit cell fuel cell that can be made thinner.

  A second object of the present invention is to provide a fuel cell having a stack structure that can be miniaturized by stacking a plurality of such unit cells.

  A third object of the present invention is to provide a fuel cell manufacturing method capable of improving power generation efficiency.

The fuel cell of the present invention includes a pair of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode, and an entire outer peripheral portion between the pair of membrane electrode assemblies in which the anode electrodes face each other. And a unit cell configured to include a fuel inlet for supplying fuel into a bag-shaped region surrounded by the seal layer.
In this invention, the anode electrodes of the pair of membrane electrode assemblies to which fuel is supplied are opposed to each other to form a bag-like region, so that fuel can be supplied only from the fuel inlet to the anode electrode in the bag-like region. Further, a special separator for separating from the air supplied to the cathode electrode side is not necessary, and the unit cell is formed only by the constituent members made of a film or a layer, so that the thickness is further reduced.

The fuel cell of the present invention is a gas-impermeable separator for separating a fuel and air from a membrane electrode assembly in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode, and being disposed on the anode electrode side. A film, a seal layer formed over the entire outer periphery between the membrane electrode assembly and the isolation film, and a fuel inlet for supplying fuel into a bag-shaped region surrounded by the seal layer It is characterized by including a unit cell configured to be included.
In the present invention, since the gas non-permeable separating film is used for separating the fuel supplied to the anode electrode and the air (oxygen) supplied to the cathode electrode, a thin unit cell can be obtained.

The fuel cell of the present invention is characterized in that the above-described unit cells and sheet-like air permeable members for supplying air to the cathode electrode side of the unit cells are alternately stacked.
According to the present invention, since the fuel cell is configured by laminating thin unit cells whose members are membranes and sheet-like air permeable members, a large number of unit cells are laminated to obtain an output. Even if the fuel cell is configured, the fuel cell itself does not become thick and a small fuel cell can be obtained.

In this invention, the structure by which the gas impermeable layer was provided in the part in which the said electrode of the said membrane electrode assembly is not formed is preferable.
In the present invention, the gas impermeable layer is provided on the polymer solid electrolyte membrane in which the anode electrode and the cathode electrode of the membrane electrode assembly are not provided. The polymer solid electrolyte membrane is proton permeable and easily penetrates hydrogen fuel. Therefore, by providing these gas impermeable layers where necessary, gas leakage from the bag-like region can be prevented more reliably.

In the method for producing a fuel cell of the present invention, a pair of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode are arranged so that the anode electrodes face each other, and between the anode electrodes A step of arranging the extraction electrode, a step of forming a seal layer on the entire outer periphery of the membrane electrode assembly while applying a load from the opposing direction to the pair of membrane electrode assemblies arranged, and the load And a step of forming a unit cell by solidifying the sealing layer in a state in which is added.
According to the present invention, when a load is applied to the membrane electrode assembly, the anode electrode between the membrane electrode assemblies and the extraction electrode as the constituent member are more closely attached to reduce the contact resistance. Since the membrane electrode assembly is fixed with the seal layer in the state where the load is applied, the contact resistance is kept low and the power generation efficiency of the unit cell is improved.

According to the fuel cell manufacturing method of the present invention, a gas non-permeable separating film is provided so as to face the anode electrode with respect to a membrane electrode assembly in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode. And arranging the extraction electrode between the isolation film and the anode electrode, and the membrane electrode while applying a load from the opposing direction to the membrane electrode assembly and the isolation film. A step of forming a seal layer on the entire outer periphery between the joined body and the isolation film, and a step of forming a unit cell by solidifying the seal layer in a state where this load is applied. Features.
According to this invention, by applying a load to the membrane electrode assembly and the isolation film, the anode electrode between the membrane electrode assembly and the isolation film and the extraction electrode which is a constituent member are more closely attached, and the contact resistance is reduced. To reduce. Since the gap between the membrane electrode assembly and the isolation film is fixed with the seal layer in the state where the load is applied, the contact resistance is kept low and the power generation efficiency of the unit cell is improved.

According to the fuel cell manufacturing method of the present invention, a plurality of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode are arranged, and extraction electrodes are respectively arranged outside the anode electrode and the cathode electrode. A step of alternately stacking the plurality of membrane electrode assemblies and a sheet-like air permeable member for supplying air to the cathode electrode side, and a plurality of stacked membrane electrode assemblies, A step of fixing at least the membrane electrode assemblies sandwiching the air permeable member while applying a load from the stacking direction.
According to the present invention, even in the case of the stack structure, a state in which a load is applied to a portion that requires electrical conductivity between the constituent members is maintained by interposing the sheet-like air permeable member between the membrane electrode assemblies. Fixed. Even in the case of lamination, the contact resistance between the constituent members is lowered, and the power generation efficiency of the fuel cell is improved.
The process of fixing the membrane electrode assemblies may be fixed at a time in a stacked state, but the portion requiring airtightness is fixed in advance to form unit cells, and then the unit cells are stacked. May be fixed. When a part requiring airtightness is fixed in advance, the parts of the part are not easily displaced, and the airtightness is further increased.

  According to the fuel cell and the manufacturing method thereof of the present invention, the fuel cell can be configured with a small number of thin components, and the fuel cell can be reduced in thickness and size. Moreover, since the state which applied the load between structural members can be maintained, the contact resistance between structural members is low, and there exists an effect which can improve electric power generation efficiency.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 and 2 show a cross-sectional view of the fuel cell 1 according to the present embodiment and a plan view of the membrane electrode assembly 2. 3 and 4 show a process of forming the unit cell 7.

  In FIG. 1, a fuel cell 1 includes a pair of sheet-like membrane electrode assemblies 2 in which a solid polymer electrolyte membrane 3 is sandwiched between an anode electrode 4 and a cathode electrode 5 from both sides. As shown in FIG. 2, a gas impermeable layer 6 for preventing gas leakage from the polymer solid electrolyte membrane 3 is formed on the outer periphery of the membrane electrode assembly 2 where the electrodes 4 and 5 are not provided. Has been. The pair of membrane electrode assemblies 2 form unit cells 7 by facing the anode electrode 4 and sealing the outer periphery with a sealing layer 8.

The polymer solid electrolyte membrane 3 is made of a stretched porous polytetrafluoroethylene (PTFE) film, which is a porous membrane, and a perfluorosulfonic acid such as Nafion (trademark of DuPont), which is a polymer solid electrolyte resin. It is constituted by impregnation with a polymer, fluorine polymer, hydrocarbon polymer or the like.
Hydrogen, which is a fuel, is supplied to the anode electrode 4, and air (oxygen) is supplied to the cathode electrode 5. Each electrode is made of carbon on which a catalyst such as platinum or a platinum alloy for promoting a reaction of hydrogen oxidation or oxygen reduction is supported.

As the gas impermeable layer 6, a film-like resin, a metal thin film layer, or a combination thereof can be used. As a resin having low gas permeability, EVOH (ethylene-vinyl alcohol copolymer), acetylated polymer glucomannan, or the like can be used.
The sealing layer 8 is a heat-welded film made of a thermoplastic resin that can be solidified after being deformed by heat (polyester, polyolefin, polyamide, acrylic, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, and their It may be a mixture) or a photocurable resin (visible light curable type, UV curable type) that is solidified by light.

  In the unit cell 7, a conductive mesh-like intermediate member 9 is arranged in contact with each of the opposing anode electrodes 4. The intermediate member 9 forms a current collector that collects electrons generated in the hydrogen diffusion layer and the anode electrode 4. The intermediate member 9 is provided with an extraction electrode 10 for extracting generated electric power to the outside. Further, a support 11 that permeates hydrogen is sandwiched between the extraction electrodes 10 facing each other.

The unit cell 7 is provided with a hydrogen inlet 12. Here, the hydrogen inlet 12 and the extraction electrode 10 are extended from the inside while being sealed between the sealing layers 8 and kept airtight, and are drawn out to the outside. Accordingly, the unit cell 7 is formed in an airtight bag shape, and hydrogen is supplied from the hydrogen inlet 12.
The cathode electrodes 5 on both sides are provided with a diffusion layer for uniformly supplying oxygen to the cathode electrode 5 and an intermediate member 13 serving as a current collector so as to be in contact with each other. An extraction electrode 14 is provided for collecting the incoming electrons. The extraction electrode 14 is drawn out in the direction of the front and back of FIG.

The intermediate members 9 and 13 are for uniformly supplying hydrogen and oxygen to the electrodes, and electrically connect the electrodes 4 and 5 to the extraction electrodes 10 and 14. Therefore, a porous conductive material is used. The material for forming the intermediate members 9 and 13 may be, for example, a mesh metal foam (for example, steel wool), aluminum, stainless steel, etc., or a porous metal material such as sponge titanium or carbon paper. A material carrying carbon or a carbon cloth may be used.
The extraction electrodes 10 and 14 are mesh members with low electrical resistance that allow hydrogen and oxygen to pass through. For example, a metal mesh can be used, or a metal foil having an arbitrary shape can be used. What is necessary is just to have. In this embodiment, an insulator is used for the support 11, and one of the extraction electrodes 10 and one of the extraction electrodes 14 are connected in series. In this case, the electromotive force of the unit cell 7 can be increased.

  The support 11 can be made of a porous material. For example, the conductive porous material may be a foam metal, a metal filter or the like, and the insulating porous material may be a foam resin such as foam resin, foam quartz or foam glass, or water repellent fiber. It may be a filter or the like. Further, glass fibers, beads or the like may be dispersed between the layers. Furthermore, a large through-hole may be opened with a porous material to improve air permeation performance.

Below, the manufacturing method of the fuel cell 1 (unit cell 7) is demonstrated with reference also to FIG. 3, FIG.
First, as shown in FIG. 3, the anode electrode 4 of the pair of membrane electrode assemblies 2 is disposed so as to face each other, and the intermediate member 9, the extraction electrode 10, the support 11, and the hydrogen inlet 12 are positioned and disposed therebetween. The sealing agent 8a is disposed on the outer periphery.

Next, as shown in FIG. 4, a load is applied to the pair of membrane electrode assemblies 2 from the opposing direction (the direction of the arrow) via the pressing plate 18. It is desirable that the load be 10 Kg / cm ² or more and a pressure that does not break the parts. In a state where a load is applied, the seal layer 8 is formed by solidifying by irradiation with heat or light according to the resin of the sealant 8a (FIG. 3) to be used. When a heat-sealing film is used as the sealant 8a, it is solidified by cooling after applying heat. By doing so, the extraction electrode 10, the intermediate member 9, and the anode electrode 4 of the unit cell 7 can be fixed in close contact with each other under a load.
The fuel cell 1 functions in a state where the cathode side intermediate member 13 and the extraction electrode 14 are added to the unit cell 7 formed as described above.

Below, the state of gas flow and electricity generation in the fuel cell 1 will be described.
Hydrogen as fuel is introduced from the hydrogen inlet 12, passes through the extraction electrode 10, reaches the anode electrode 4 through the intermediate member 9. In the anode electrode 4, hydrogen ions H ⁺ and electrons e ⁻ are generated by the action of the catalyst. The generated electrons e ⁻ are collected on the extraction electrode 10 through the intermediate member 9. The generated hydrogen ions H ⁺ permeate the polymer solid electrolyte membrane 3 and move to the cathode electrode 5, thereby generating a potential difference with the anode electrode 4. Here, when a load is connected between the extraction electrodes 10 and 14, the electrons e ⁻ move to the cathode electrode 5 through the extraction electrode 14 and the intermediate member 13 through the load.

On the other hand, oxygen in the air is supplied to the cathode electrode 5. Hydrogen ions H ⁺ that have reached the cathode electrode 5 through the polymer solid electrolyte membrane 3 react with oxygen in the air and electrons e ⁻ that have passed through the load due to the action of the catalyst to produce water. The generated water and the remaining gas in the air that did not contribute to the reaction are again discharged into the air.

According to this embodiment, there are the following effects.
(1) Since the bag-like region is formed by facing the anode electrodes 4 of the pair of membrane electrode assemblies 2 to which hydrogen is supplied, hydrogen is supplied only from the hydrogen inlet 12 to the anode electrode 4 in the bag-like region. This makes it possible to eliminate the need for a special separator for separating the air supplied to the cathode electrode 5 side. In addition, since the unit cell 7 is formed of a constituent member made of a film or a layer, the pair of membrane electrode assemblies 2 are not so thick even if they are overlapped. Therefore, the entire fuel cell 1 can be made thinner.

(2) A gas impermeable layer 6 is formed on the portion of the solid polymer electrolyte membrane 3 where the anode electrode 4 and the cathode electrode 5 are not provided. The polymer solid electrolyte membrane 3 is proton permeable and easily permeable to hydrogen fuel. However, by providing these gas non-permeable layers 6 at necessary places, leakage of hydrogen from the bag-like region can be ensured. Can be prevented.

(3) By applying a load to the membrane electrode assembly 2, the anode electrode 4 between the membrane electrode assemblies 2, the intermediate member 9, which is a constituent member, and the extraction electrode 10 can be brought into closer contact with each other. Resistance can be reduced. And since the gap between the membrane electrode assemblies 2 is fixed by the seal layer 8 with the load applied, the contact resistance can be kept low and the power generation efficiency of the unit cell 7 can be improved.

(4) When the unit cell 7 is formed, a load is applied to the intermediate member 9 and the extraction electrode 10 to fix the unit cell 7 with the seal layer 8, so that gaps and bubbles in the seal layer 8 can be reduced, and the unit cell 7 has a bag shape. The airtightness of the region can be improved.

(Second embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. 5 and 6 show an overall view and a cross-sectional view of the fuel cell 20 having a stack structure according to the present embodiment. 7 and 8 show a method for stacking the unit cells 7. In addition, the same code | symbol is attached | subjected to the same structural member as 1st embodiment, and those description here is abbreviate | omitted or simplified. The same applies to the third embodiment described later.

In FIG. 5, the fuel cell 20 has a stack structure in which the unit cells 7 shown in the first embodiment are stacked. The fuel cell 20 is covered on one side with a hood 17. Here, the air in the hood 17 is sucked in the direction of the arrow. Accordingly, the supply of air to the fuel cell 20 and the discharge of water generated in the fuel cell 20 are promoted, and the reaction proceeds more efficiently.
In this embodiment, hydrogen inlets are not shown, but they are combined into one and hydrogen is introduced all at once. Hydrogen is combined with oxygen by the reaction in the fuel cell 1 and discharged as water. Therefore, if the supply amount is controlled, a hydrogen outlet is not necessary, but if control is difficult, a hydrogen outlet may be provided.

In the fuel cell 20 having a stack structure, as shown in FIG. 6, sheet-like air permeable members 15 for supplying oxygen to the cathode electrode 5 are sandwiched and stacked. Between the unit cells 7, sheet-like air permeable members 15 are sandwiched and stacked. As this gas permeable member 15, the same thing as the support body 11 can be used.
The outer periphery is fixed with an adhesive layer 16 between the unit cell 7 and the air permeable member 15. At this time, the air permeable member 15 is sandwiched by the adhesive layer 16 and drawn out to introduce air, and oxygen in the air enters from the end face of the gas permeable member 15 and is supplied to the cathode electrode 5. The generated water and the remaining air are discharged.
The adhesive layer 16 only needs to be able to fix the units, and may be one that transmits air. For example, a double-sided tape having adhesive layers on both sides of paper or sponge may be used.

  In FIG. 6, a sheet-like air permeable member 15 for supplying oxygen to the three unit cells 7 and the two cathode electrodes 5 and an adhesive layer 16 for fixing them are shown. Any number of these layers may be laminated. In the drawing, the upper and lower intermediate members 13 and the extraction electrode 14 are omitted.

Below, the manufacturing method of the fuel cell 20 is demonstrated with reference also to FIG. 7, FIG.
First, as shown in FIG. 7, the unit cell 7, the intermediate member 13, the extraction electrode 14, the air permeable member 15, and the adhesive member 16a are laminated. Here, in the step of forming the unit cell 7, the position of each component inside the seal layer 8 is fixed in advance by solidifying the sealant 8a.
Next, as shown in FIG. 8, adhesion is performed by applying a load uniformly from the stacking direction through the pressing plates 18 from both sides. The load may be approximately the same as the load when the unit cell 7 is formed. At this time, in order to reduce the contact resistance between the constituent members of the fuel cell 20, it is necessary to maintain a state in which a load is applied. As a result, there can be obtained a state in which force is uniformly applied to the members constituting the fuel cell 20 as compared with a separator having a conventional rib.

Hereinafter, the flow of air and the flow of discharged water will be briefly described.
Oxygen in the air is supplied mainly through the air permeable member 15 or the adhesive layer 16. Hydrogen ions H ⁺ that have reached the cathode electrode 5 through the polymer solid electrolyte membrane 3 react with oxygen in the air and electrons e ⁻ that have passed through the load due to the action of the catalyst to produce water. The remaining water in the air that did not contribute to the reaction with the generated water is exhausted through the air permeable member 15 and the adhesive layer 16.

According to this embodiment, there are the following effects.
(5) Since the fuel cell 20 is constructed by laminating the thin unit cells 7 whose constituent members are membranes and the sheet-like air permeable members 15, a large number of unit cells 7 are laminated to obtain output. Even if this fuel cell 20 is configured, the fuel cell 20 itself does not become thick, and a small fuel cell 20 can be obtained.

(6) Since each component member is fixed in a state where a load is applied to the extraction electrodes 10 and 14 and the air permeable member 15 which are the component members of the fuel cell 20, the portion where conductivity between the component members is required They can be fixed together with reduced contact resistance. Therefore, even when stacked, the contact resistance between the constituent members can be lowered, and the power generation efficiency of the fuel cell can be improved.

(7) If the unit cell 7 needs to be hermetically sealed in advance to form a unit cell, and then the unit cell 7 is stacked and fixed, the components in the unit cell 7 are less likely to be displaced, Further, the airtightness of the unit cell 7 can be enhanced.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.
FIG. 9 shows the unit cell 7 of the second embodiment. In this embodiment, the anode electrode 4 and the cathode electrode 5 are laminated facing each other. A stack structure fuel cell can be obtained by laminating the unit cells 7 alternately with the gas permeable members 15 via the adhesive layers 16 in the same manner as in the second embodiment, but the illustration and description here are omitted. To do.

  In FIG. 9, an anode electrode 4 and a cathode electrode 5 are formed on the solid polymer electrolyte membrane 3 in the same manner as in the first embodiment, and intermediate members 9 and 13 and extraction electrodes 10 and 14 are arranged on both sides of each. Is done. A gas impermeable layer 6 is also provided. In this embodiment, the support 11 is sandwiched and fixed between the extraction electrode 10 and the isolation film 19. Although the fixing method is not shown, the sealing member 8a is used as in the first embodiment, and a hydrogen inlet (not shown) is provided between the membrane electrode assembly 2 and the gas isolating film 19. . The material and configuration of the gas isolating film 19 can be the same material and configuration as the gas impermeable layer 6 exemplified in the first embodiment. In the case of a stack structure, air (oxygen) can be introduced into the cathode using the hood 17 (FIG. 5) as in the second embodiment.

In the unit cell 7, the seal layer 8 is disposed on the outer periphery of the membrane electrode assembly 2 and the isolation film 19, and a load is applied from the facing direction of the membrane electrode assembly 2 as in the first embodiment. It can be obtained by solidifying the seal layer 8.
In the case of a fuel cell having a stack structure, the unit cell 7, the air permeable member 15, and the adhesive layer 16 are stacked, and, as in the second embodiment, are obtained by fixing the whole while applying a load from the stacking direction. Can do.

According to this embodiment, there are the following effects.
(8) For separation of hydrogen supplied to the anode electrode 4 and air (oxygen) supplied to the cathode electrode 5, a gas non-permeable separating film 19 is used instead of a conventional thick separator. Therefore, the thin unit cell 7 can be obtained.

(9) By applying a load to the membrane electrode assembly 2 and the isolation film 19, the anode electrode 4 between the membrane electrode assembly 2 and the isolation film 19, the intermediate member 9 that is a constituent member, and the extraction electrode 10 The contact resistance can be reduced. For this reason, by fixing the gap between the membrane electrode assembly 2 and the isolation film 19 with the seal layer 8 with the load applied, the contact resistance can be kept low and the power generation efficiency of the unit cell 7 can be improved. Can do.

The present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the first embodiment, the pair of membrane electrode assemblies 2 are arranged in parallel by omitting the support 11 or electrically connecting the extraction electrodes 10 using the conductive support 11. It is also possible to connect. If the extraction electrodes 14 are also connected and used in this state, the electrode area as the unit cell 7 is doubled, and the battery capacity of the unit cell 7 can be increased.

  Further, in the stack type fuel cell manufacturing method shown in the second embodiment, the component parts of the unit cell 7 are fixed and stacked in advance. May be. However, it is preferable to fix the parts of the unit cell 7 in advance because there is a possibility that the parts may be displaced and the sealing performance may be lowered.

The best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

1 is a cross-sectional view of a fuel cell according to an embodiment of the present invention. The top view of a membrane electrode assembly. The figure which shows the process of arrange | positioning the structural member of a unit cell. The figure which shows the process of forming a sealing layer and a unit cell. FIG. 3 is an overall view of stacked fuel cells. Cross-sectional view of stacked fuel cells. The figure which shows the process of arrange | positioning and laminating | stacking a structural member. The figure which shows the process of fixing a structural member. 1 is a cross-sectional view of a fuel cell according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Fuel cell, 2 ... Membrane electrode assembly, 3 ... Polymer solid electrolyte membrane, 4 ... Anode electrode, 5 ... Cathode electrode, 6 ... Gas impermeable layer, 7 ... Unit cell, 8 ... Seal layer, 9 ... Intermediate member, 10 ... extraction electrode, 12 ... hydrogen inlet, 14 ... extraction electrode, 15 ... air permeable member, 16 ... adhesive layer, 19 ... isolating film, 20 ... fuel cell of stack structure.

Claims (7)

A pair of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode;
A seal layer formed over the entire outer periphery of the pair of membrane electrode assemblies facing the anode electrodes;
A fuel cell comprising a unit cell including a fuel inlet for supplying fuel in a bag-shaped region surrounded by the seal layer. A membrane electrode assembly in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode;
A gas-impermeable separating film disposed on the anode electrode side for separating fuel and air;
A sealing layer formed over the entire outer periphery between the membrane electrode assembly and the isolation film;
A fuel cell comprising a unit cell including a fuel inlet for supplying fuel in a bag-shaped region surrounded by the seal layer. A plurality of unit cells according to claim 1 or 2,
A fuel cell, wherein sheet-shaped air permeable members for supplying air to the cathode electrode side of the unit cell are alternately stacked. The fuel cell according to claim 1, wherein:
A fuel cell, wherein a gas impermeable layer is provided in a portion of the membrane electrode assembly where the electrode is not formed. A pair of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode,
Arranging the anode electrodes so as to face each other, and arranging a take-out electrode between the anode electrodes;
Forming a seal layer on the entire periphery of the outer periphery between the membrane electrode assemblies while applying a load from the opposing direction to the pair of membrane electrode assemblies arranged;
And a step of forming a unit cell by solidifying the sealing layer in a state where this load is applied. A gas non-permeable separating film is disposed so as to face the anode electrode with respect to the membrane electrode assembly in which the polymer solid electrolyte membrane is sandwiched between the anode electrode and the cathode electrode. Arranging the extraction electrode between the anode electrode;
Forming a seal layer on the entire circumference of the outer periphery between the membrane electrode assembly and the isolation film while applying a load from the opposing direction to the arranged membrane electrode assembly and the isolation film;
And a step of forming a unit cell by solidifying the sealing layer in a state where this load is applied. A plurality of membrane electrode assemblies in which a polymer solid electrolyte membrane is sandwiched between an anode electrode and a cathode electrode, and a step of disposing extraction electrodes on the outside of the anode electrode and the cathode electrode,
Alternately stacking the plurality of membrane electrode assemblies and a sheet-like air permeable member for supplying air to the cathode electrode side;
And a step of fixing at least the membrane electrode assemblies sandwiching the air permeable member while applying a load from the stacking direction to the plurality of stacked membrane electrode assemblies. Production method.

Images