JP2005268023A - Manufacturing method of assembly of solid electrolyte membrane and electrode, assembly of solid electrolyte membrane and electrode, and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent damage or deformation of an electrode or a solid electrolyte membrane and uniformly sufficiently conduct pressurization over the whole surface of the electrode or the solid electrolyte membrane. <P>SOLUTION: A laminated body 8 having a solid electrolyte membrane and electrodes 4 interposing the solid electrolyte membrane 3a between them and first deforming members 15 interposing the laminated body 8 and deformable by outside force are laminated on a sample stand 11, outside force is applied to a second deforming member 16 deformable by outside force with a pressurizing medium A, the second deforming member 16 is deformed and brought into contact with the first deforming member 15 to press the first deforming member 15 and the laminated body 8 in the laminated direction and to connect the solid electrolyte membrane 15 to the electrodes 4. Damage and deformation of the electrodes 4 or the solid electrolyte membrane 3a are prevented, and pressurization to them can uniformly sufficiently be conducted over the whole surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a solid electrolyte membrane and electrode assembly, a solid electrolyte membrane and electrode assembly, and a fuel cell.

  From the viewpoint of environmental problems represented by greenhouse gases, fuel cells as clean energy sources are being developed at a rapid pace. In particular, solid electrolyte fuel cells are being actively researched and developed because of their low-temperature operation, small size, and high power density. Among them, uniform bonding and high bonding strength between the electrode and the electrolyte are important for stable operation of the fuel cell. In addition, it is known that the electrolyte membrane around the electrode sandwiched by the separator is likely to be wrinkled when a general hot press method is used, and the generated wrinkle affects the gas sealing performance of the fuel cell. ing. Therefore, a method of selectively hot pressing the electrolyte membrane at the peripheral edge of the electrode (see Patent Document 1) with an elastic body interposed therebetween, or a method of hot pressing while holding the electrolyte membrane at the peripheral edge of the electrode with an electrode member (See Patent Document 2) and the like. Furthermore, a system (see Patent Document 3) in which the laminate is pressurized with a roller that moves by air pressure or the like is disclosed. In addition, a method of pressurizing a diffusion electrode with a cushion material (see Patent Document 4) is also disclosed for producing a diffusion electrode containing a catalyst.

JP 2000-260684 A JP 2000-223134 A JP 2000-182632 A Japanese Unexamined Patent Publication No. 59-21565

  However, in Patent Document 1 and Patent Document 2, there is no detailed description regarding uniform pressurization of the laminated body and no effective means is provided, and further, deformation of the elastic body used (particularly longitudinal and lateral deformation). ) Is not described.

  In Patent Document 3, since a roller is used, the entire surface of the laminated body cannot be essentially uniformly pressed, and the laminated body is likely to be distorted. Further, there is no description considering the deformation of the material of the roller that applies pressure to the laminate.

  In patent document 4, the influence which the deformation | transformation of a cushion material has on a diffusion electrode is not considered. In addition, although the cushion material is used, since the mechanical pressure method using a cylinder is used as a method for contacting and pressurizing the cushion material to the pressurized object, the flatness of the pressure plate is It has the disadvantage of affecting it.

  An object of the present invention is to prevent damage and deformation of an electrode and a solid electrolyte membrane, and to apply pressure to the electrode and solid electrolyte membrane uniformly and sufficiently on the entire surface.

  According to a first aspect of the present invention, there is provided a solid electrolyte membrane and electrode assembly manufacturing method comprising: a first laminate that has a solid electrolyte membrane and an electrode that sandwiches the solid electrolyte membrane; The step of laminating the deformable member on the mounting table, and applying the external force to the second deformable member that can be deformed by an external force with a pressure medium, deforming the second deformable member, and stacking the first deformed layer on the mounting table. And a step of pressing the first deformable member and the stacked body stacked on the mounting table in the stacking direction by contacting the member.

  According to a second aspect of the present invention, in the method of manufacturing a solid electrolyte membrane and electrode assembly according to the first aspect, the step of laminating the multilayer body and the first deformable member includes a plurality of the multilayer body and a plurality of the multilayer body. The first deformation member is stacked.

  According to a third aspect of the present invention, in the method of manufacturing a solid electrolyte membrane / electrode assembly according to the first or second aspect, the first deformable member is perpendicular to the pressurizing direction with respect to the deformation in the pressurizing direction. It is a member with little deformation in the direction.

  According to a fourth aspect of the present invention, in the method for manufacturing a solid electrolyte membrane / electrode assembly according to the first, second, or third aspect, the first deformable member is a porous body formed of a porous material. .

  According to a fifth aspect of the present invention, in the method for manufacturing a solid electrolyte membrane and electrode assembly according to the first, second, third, or fourth aspect, the step of laminating the multilayer body and the first deformable member includes the lamination layer. A step of laminating a sliding member for improving slippage between the body and the first deformable member.

  According to a sixth aspect of the present invention, in the method for manufacturing a solid electrolyte membrane / electrode assembly according to the fifth aspect of the present invention, the sliding member is flexible and has an elongation rate in a direction perpendicular to the pressing direction. It is a member having a smaller elongation rate in the direction perpendicular to the pressing direction of one deformable member.

  The invention according to claim 7 is the method of manufacturing the solid electrolyte membrane and electrode assembly according to claim 5 or 6, wherein the sliding member includes a base material having an elongation percentage smaller than that of the first deformable member and the base material. And a sliding layer provided on the surface.

  According to an eighth aspect of the present invention, in the method for manufacturing a joined body of a solid electrolyte membrane and an electrode according to any one of the first to seventh aspects, the pressurizing medium is a gas.

  According to a ninth aspect of the present invention, in the method for manufacturing a solid electrolyte membrane / electrode assembly according to the eighth aspect, the gas is air.

  According to a tenth aspect of the present invention, in the method for manufacturing a solid electrolyte membrane / electrode assembly according to any one of the first to seventh aspects, the pressurizing medium is a liquid.

  An eleventh aspect of the present invention is the method for producing a joined body of a solid electrolyte membrane and an electrode according to any one of the first to tenth aspects, further comprising the step of heating the laminated body laminated on the mounting table.

  A solid electrolyte membrane / electrode assembly according to a twelfth aspect of the present invention is manufactured by the method for manufacturing a solid electrolyte membrane / electrode assembly according to any one of the first to eleventh aspects.

  A fuel cell according to a thirteenth aspect of the present invention includes the solid electrolyte membrane-electrode assembly according to the twelfth aspect of the invention, and generates electric power using the fuel supplied to the assembly.

  The invention according to claim 14 is the fuel cell according to claim 13, wherein the fuel is a fuel containing alcohol.

  According to a fifteenth aspect of the present invention, in the fuel cell according to the fourteenth aspect, the alcohol is ethanol.

  According to the first aspect of the present invention, the electrode and the solid electrolyte membrane can be prevented from being damaged and deformed, and the pressure to the electrode and the solid electrolyte membrane can be uniformly and sufficiently applied to the entire surface.

  According to invention of Claim 2, a laminated body can be pressurized uniformly and productivity can be improved further.

  According to invention of Claim 3 or 4, generation | occurrence | production of wrinkles can be suppressed reliably, damage and deformation | transformation of a laminated body can be prevented, and a laminated body can be pressurized uniformly.

  According to invention of Claim 5, 6 or 7, generation | occurrence | production of a wrinkle is suppressed reliably, damage and deformation | transformation of a laminated body can be prevented, and a laminated body can be pressurized uniformly.

  According to invention of Claim 8 or 10, a laminated body can be pressurized uniformly easily.

  According to invention of Claim 9, the pressurization with respect to a laminated body can be performed more simply and at low cost.

  According to the eleventh aspect of the present invention, the bonding strength of the laminate can be further increased.

  According to invention of Claim 12 or 13, there exists an effect similar to invention of any one of Claim 1 thru | or 11.

  According to the fourteenth aspect of the present invention, the driving time of the fuel cell can be improved by using the fuel having a high energy density.

  According to the fifteenth aspect of the present invention, it is possible to provide a fuel cell using a fuel having high environmental conservation and safety.

  The best mode for carrying out the present invention will be described with reference to FIGS.

  First, taking a fuel cell 1 using a proton conducting solid polymer electrolyte as an example, the concept of power generation will be described with reference to FIG. FIG. 1 is an explanatory diagram for explaining a power generation concept of the fuel cell 1.

  The fuel cell 1 (single cell 2) is provided with an electrolyte 3 (here, for example, proton conductor) as an ionic conductor at the center as basic components, and an anode 4a and a cathode as electrodes 4 on both sides thereof. 4b is arranged. The anode 4 a and the cathode 4 b are connected via an external circuit (load) 5. The anode 4a and the cathode 4b are provided with separators 6 each having a fuel flow path 6a for supplying fuel to each. The two separators 6 sandwich the electrolyte 3 and the electrode 4 opposed thereto.

Here, when the proton conductive electrolyte 3 is used, a fuel (hydrogen (H ₂ ), alcohol, or the like) serving as a proton source is supplied to the anode 4a side, and hydrogen is generated from the fuel by the catalytic action in the anode 4a. Ions (H ⁺ ) are generated. At this time, the generated electrons (e ⁻ ) flow to the external circuit 5. The generated hydrogen ions propagate through the electrolyte 3 and reach the cathode 4b. By supplying an oxidizing agent (air, oxygen (O ₂ ), etc.) to the cathode 4b side, hydrogen ions, oxygen, and electrons flowing through the external circuit 5 react to generate water (H ₂ O). The This is the concept of power generation, which can be expressed as the following reaction equation.

Anode reaction: H ₂ → 2H ⁺ + 2e ⁻ (in the case of hydrogen fuel)
Cathode reaction: 2H ⁺ + 1 / 2O ₂ + 2e ⁻ → H ₂ O
Total reaction: H ₂ + 1 / 2O ₂ → H ₂ O
Here, the power generation element requires the anode 4a, the cathode 4b, and the electrolyte 3. Among the power generation elements of the fuel cell 1, the membrane electrolyte membrane 3 a that is the electrolyte 3 and the electrode 4 (the anode 4 a and the cathode 4 b) are a laminate 8 in a laminated state, and the laminate 8 is pressure-bonded. The joined body 8a is formed in the joined state. In addition, in the joined body 8a of the electrolyte membrane 3a and the electrode 4 of the fuel cell 1, it is necessary that the interface between the electrode 4, the catalyst, and the electrolyte membrane 3a is sufficiently formed.

  In the present embodiment, at least a solid electrolyte membrane 3a and an electrode 4 supporting a catalyst in a manufacturing method for manufacturing a joined body 8a composed of a solid electrolyte membrane 3a (hereinafter referred to as a solid electrolyte membrane 3a) and an electrode 4. The laminated body 8 is pressed with a pressurizing medium A such as gas or liquid through deformable members 15 and 16 (described later) that can be deformed by an external force, so that no wrinkles are generated around the electrode 4. The body 8 can be uniformly pressurized. Note that the joined body 8a in the present embodiment refers to a joined body of the solid electrolyte membrane 3a and the electrode 4 which are overlapped and joined, for example, on the general shape of the joined body 8a, that is, on both surfaces of the solid electrolyte membrane 3a. This refers to the joined body 8a joined by overlapping the electrodes 4 (area of the solid electrolyte membrane 3a> area of the electrode 4). The number relationship between the solid electrolyte membrane 3a and the electrode 4 and the size relationship between them may be any relationship as long as they have overlapping portions.

  Next, the pressurizing apparatus 10 that pressurizes the laminated body 8 in order to manufacture the joined body 8a will be described with reference to FIGS. FIG. 2 is a central longitudinal side view schematically showing the pressurizing apparatus 10 of the present embodiment, and FIG. 3 is a plan view thereof.

  The pressurizing device 10 includes a sample table 11 on which the stacked body 8 is mounted, a flat plate 12 that supports the sample table 11, a flat plate 13 that faces the sample table 11, and the sample table 11 and the flat plate 13. The gap member 14 is formed with a predetermined gap therebetween. At this time, the laminate 8 is sandwiched between the two first deformable members 15 and placed on the sample stage 11.

  A second deformation member 16 that can be deformed by an external force and applies pressure to the stacked body 8 is provided on the sample table 11 side of the flat plate 13. The second deformation member 16 is fixed by a fixing member 17, and the flat plate 13 and the second deformation member 16 are held in a sealed state. The flat plate 13 is provided with a pressurized medium supply port 18 that is a through hole for supplying the pressurized medium A so as to face the second deformable member 16. A pressurized medium supply pipe 19 for supplying the pressurized medium A is connected to the pressurized medium supply port 18 between the flat plate 13 and the second deformation member 16. The other end of the pressurized medium supply pipe 19 is connected to a pressurized medium accommodating portion (not shown) that accommodates the pressurized medium A. For example, when the pressure medium A is air, the pressure medium storage unit is provided with a pressure pump that generates a pressurizing force for supplying air. Further, in the path of the pressurized medium supply pipe 19, a valve 20 for opening and closing the pressurized medium supply pipe 19, a joint 21 for connecting the pressurized medium supply pipe 19 and another pipe, and a pressure gauge 22 for measuring pressure are provided. ing. When the valve 20 is opened, the pressurized medium A is supplied between the flat plate 13 and the second deformable member 16 via the pressurized medium supply pipe 19 from the pressurized medium accommodating portion. As a result, the second deformable member 16 swells toward the stacked body 8 placed on the sample stage 11 and applies pressure to the stacked body 8.

  The flat plate 13 is provided with a discharge port 23, which is a through hole for adjusting the pressure applied to the stacked body 8 by discharging the pressurized medium A and facing the second deformation member 16. The discharge port 23 is provided with a lid (not shown) that closes the discharge port 23, and the sealed state between the flat plate 13 and the second deformable member 16 is maintained. When the pressure is confirmed by the pressure gauge 22 and the pressure becomes higher than necessary, the discharge port 23 is opened, and the pressure applied to the laminate 8 by the second deformable member 16 is adjusted.

  In such a configuration, the pressurizing operation on the stacked body 8 will be described with reference to FIGS. FIG. 4 is a central longitudinal sectional side view schematically showing the pressurizing apparatus 10 in a pressurized state.

  First, the operator places the first deformable member 15 on the sample stage 11, places the laminated body 8 thereon, and further places the first deformable member 15 thereon. Here, the process of laminating the laminated body 8 and the first deformable member 15 on the sample stage 11 is executed.

  Thereafter, the operator opens the valve 20 and supplies the pressurized medium A between the flat plate 13 and the second deformable member 16 via the pressurized medium supply pipe 19 from the pressurized medium accommodating portion. As a result, the second deformable member 16 swells toward the laminated body 8 by the pressurizing medium A, and comes into close contact with the first deformable member 15 to uniformly pressurize the laminated body 8. Here, a step of pressing the first deformable member 15 and the stacked body 8 stacked on the sample stage 11 in the stacking direction is executed. At this time, the pressure applied to the laminated body 8 is confirmed by the pressure gauge 22, and when the pressure becomes excessive, the pressure is adjusted by discharging air from the discharge port 23.

  In such a pressing operation, the first deformation member 15 exists between the stacked body 8 and the second deformable member 16, and further, the first deformation is also formed between the sample stage 11 and the stacked body 8. Member 15 is present. This makes it difficult to transmit the deformation of the second deformable member 16 in the lateral direction (horizontal direction) to the stacked body 8, so that damage and deformation of the electrode 4 and the solid electrolyte membrane 3 a can be prevented. Furthermore, the laminate 8 can be uniformly pressurized. Here, if the thickness of the second deformable member 16 becomes thicker, it becomes easier to apply pressure uniformly to the laminate 8, but as the thickness increases, the second deformable member becomes difficult to deform and deforms it. Since the pressure also increases, it is not preferable to increase the thickness of the second deformation member 16. Further, a flexible release layer may be provided between the first deformable member 16 and the laminate 8. Thereby, the 1st deformation member 16 can be easily removed from the laminated body 8. FIG.

  Further, when air is used as the pressurized medium A, air can be easily supplied and discharged by an air compressor or the like. Air is continuously supplied from the pressurizing medium supply port 18 until a necessary pressure is obtained, and after the pressurization is finished, the pressurization is released by exhausting from the discharge port 23. Air is inexpensive as the pressurized medium A and is easy to handle.

  Moreover, productivity can be improved by installing many laminated bodies 8 in the space between the sample stand 11 and the 2nd deformation member 16. FIG. At this time, it is possible to install a plurality of laminated bodies 8 in the horizontal direction with respect to the sample stage 11, and it is also possible to install a plurality of laminated bodies 8 in the vertical direction with respect to the sample stage 11. In particular, when a plurality of laminated bodies 8 are stacked in a direction perpendicular to the sample stage 11, the occupied floor area efficiency for the production of the laminated bodies 8 is good, and the productivity is increased. However, when a plurality of laminated bodies 8 themselves are stacked, it becomes difficult to uniformly pressurize each laminated body 8 due to uneven thickness of the laminated bodies 8 themselves. Therefore, when a plurality of stacked bodies are stacked, the first deformable member 15 is disposed between them to prevent uneven pressing on each stacked body 8.

  Here, the 2nd deformation member 16 is formed with the member which is impermeable with respect to the gas and liquid to be used. Such a member has a low permeability to the pressurized medium A such as gas or liquid, can be deformed by an external force and can be in close contact with the laminate 8, and the deformation can be maintained without a large change in the external force. It is. That is, in the present embodiment, since the second deformable member 16 transmits gas pressure, liquid pressure, and the like to the laminate 8, a member having a high permeability of the pressurized medium A cannot be used as the second deformable member 16. . Specifically, a metal thin plate such as aluminum or copper, or natural rubber or synthetic rubber is used, and further, an elastic resin such as urethane rubber, silicon rubber, or fluororubber is used. As judged from the specific example, “impermeable” in the present embodiment does not mean that the pressurized medium A is not transmitted at all, and gas, liquid, and the like are substantially transmitted. It means a difficult member.

  Moreover, it is preferable that the 1st deformation member 15 is a member with few deformation | transformation to the orthogonal | vertical direction with respect to the pressurization direction with respect to the deformation | transformation to a pressurization direction. This is because, when the first deformable member 15 is in contact with the laminated body 8, the object of the present invention is sufficiently achieved if pressure is applied only in the laminating direction of the laminated body 8. Actually, since the first deformable member 15 is a deformable member, deformation in the thickness direction of the first deformable member 15 itself (deformation in which the thickness is reduced) due to pressurization in the stacking direction of the stacked body 8 is horizontal. Therefore, a force to extend the surface of the laminate 8 is applied to the surface of the laminate 8. When this force is large, the electrode 4 of the laminated body 8 is broken at worst. In order to prevent this, the first deformable member 15 is preferably a member that is less deformed in the direction perpendicular to the pressurizing direction than the deformed in the pressurizing direction.

  Such a member is preferably a porous body formed of a porous substance. Since the first deformable member 15 is porous, the elongation in the horizontal direction due to the deformation in the thickness direction can be absorbed by the hole portion. This makes it possible to reduce deformation in the direction perpendicular to the pressurizing direction with respect to deformation in the pressurizing direction. Furthermore, the material is preferably an elastic body.

  Furthermore, to the laminated body 8 by letting the deformation in the thickness direction of the first deformable member 15 itself (deformation in which the thickness is reduced) due to the pressurization in the laminating direction of the laminated body 8 as the horizontal deformation (deformation that extends). This non-uniform pressurization is further effectively prevented by providing a sliding member 24 for improving the sliding between the laminate 8 and the first deformation member 15. As shown in FIG. 5, the sliding member 24 is interposed between the first deformable member 15 and the laminated body 8. Therefore, the sliding member 24 is crushed and deformed in the thickness direction when pressed, and avoids the close contact between the first deformable member 15 and the laminated body 8 which is about to extend in the pressing direction and the vertical direction thereof, and In order to improve the sliding of the first deformation member 15 in the horizontal direction, the laminated body 8 is hardly affected by the volume change of the first deformation member 15.

  Here, as the material of the sliding member 24, it is also possible to use a material that does not adhere and is easy to release, that is, a material having releasability. However, even if there is no close contact with the surface of the first deformable member 15 or the laminated body 8 and the mold release is easy, slippage is sufficient for deformation of the first deformable member 15 in the extending direction depending on the pressure and heating conditions. In addition, a material that itself easily stretches is not suitable as the sliding member 24 of the present embodiment.

  Further, the form of the sliding member 24 may be powder or liquid, or may be one in which the sliding member 24 is formed on the first deformable member 15. Further, a sheet-like member can be used as the sliding member 24. Specific examples of the material for imparting slip include inorganic materials such as tungsten disulfide and boron nitride, fluorine-based materials such as Teflon (registered trademark), silicone, paraffin, glycine, and the like. Is not to be done.

  Note that the preferred sliding member 24 has flexibility so as not to impair the effect of uniform pressurization by the first deformable member 15, and the elongation rate in the direction perpendicular to the pressurizing direction is the first. It is preferable that the deformation rate of the deformable member 15 is smaller than that in the direction perpendicular to the pressing direction. This is because the stress applied to the laminated body 8 can be reduced when the one having a smaller horizontal deformation is in contact with the laminated body 8. In addition, a sliding effect occurs on either or both surfaces of the laminate 8 and the first deformable member 15 that are in contact with each other, and preferably has a sliding effect on both surfaces.

  Here, when the sliding member 24 is a member that is easily deformed in the horizontal direction, the sliding member 24 is also deformed along with the extension (horizontal deformation) of the first deforming member 15. For example, if the thickness of a releasable material such as Teflon (registered trademark) is thinned to make it flexible and used as a carrier, stretching is likely to occur depending on the pressure and heating conditions. The effect of this form becomes small. However, if the elongation rate of the sliding member 24 is smaller than the elongation rate of the first deformable member 15, the effect of the present embodiment can be obtained. That is, if the sliding occurs sufficiently with respect to the surface of the electrode 4, the electrode 4 can be prevented from being damaged. More desirably, a thin and flexible material that hardly deforms with respect to the stretching of the first deformable member 15 is used as a base material, and a sliding layer is provided on the surface thereof. Specifically, plant fibers, glass fibers, polymer sheets, polymer fibers, and the like are used as the sheet-like base material. Among them, vegetable fibers (paper or the like) are preferably used because they are less deformed by stretching with respect to the first deformable member 15, are less stretched even during heating, and are inexpensive.

  Furthermore, by applying heat, the adhesion between the solid electrolyte membrane 3a and the electrode 4 becomes stronger. As a form of heating, there is a method of heating the pressurizing device 10 in a high temperature environment. In this case, since it is not necessary to add a heating control unit (not shown) to the pressurizing device 10, the laminate 8 is most simply heated. At this time, the pressure medium A can be discharged from the discharge port 23 in order to adjust the volume change of the pressure medium A due to the temperature change. Moreover, after setting so that a pressurization force may be acquired on the set temperature conditions, the pressurization apparatus 10 can also be heated. As another form, a heat source (not shown) is installed on the inside of the pressurized medium supply port 18 and the second deformable member 16, on the sample table 11, etc., and each member is heated by the heat source and laminated. The body 8 may be heated. Furthermore, as another form, you may make it heat the flat plate 12 and 13 of the pressurization apparatus 10, and heat the laminated body 8. FIG. Alternatively, the laminate 8 may be heated by the second deformable member 16 by heating the pressure medium A with a heat source (not shown). In any case, since the volume expansion of the gas occurs during heating, it is preferable to control the change in pressure on the laminate 8.

  Thus, in the joined body 8a of the electrolyte membrane 3a and the electrode 4 formed by the manufacturing method of the present embodiment, the interfaces of the solid electrolyte membrane 3a, the electrode 4 and the catalyst are sufficiently uniformly formed by uniform pressurization. ing. By pressurizing the laminated body 8 with a uniform pressure, the fuel cell 1 having excellent sealing properties with less generation of wrinkles due to distortion in the solid electrolyte membrane 3a around the electrode 4 can be obtained. As the fuel, gaseous fuel or liquid fuel is used. In particular, since the joined body 8a manufactured by the manufacturing method of the present embodiment has no unevenness in the bonded state due to uniform pressurization, peeling due to expansion of the solid electrolyte membrane 3a due to the liquid fuel hardly occurs. Accordingly, liquid fuel can be used, and the fuel cell 1 can take an excellent form in which the diffusibility of the fuel to the catalyst unit is maintained.

The fuel used in the present embodiment is appropriately set in accordance with the fuel cell 1, but basically any fuel can be used. However, it is preferable to use a fuel excellent in volume and weight energy density. In particular, a fuel excellent in volume energy density is preferable. Therefore, gaseous fuel is not preferable because it is inferior in volumetric energy density, and liquid fuel is preferable. This is because, for example, the number of electrons that can be extracted by oxidation reaction of one molecule is 2 if hydrogen, 6 if methanol, and 12 if ethanol, so the amount of Coulomb that can be extracted from 1 mol of each molecule is theoretical. The values are 96500 × 2C, 96500 × 6C, and 96500 × 12C. Considering density and molecular weight of each, 1 cm ³ per coulomb amount converted to the about 9C / cm ³ with hydrogen, approximately methanol 14400C / cm ^3, the energy density of 15200C / cm ³ with ethanol. Hydrogen as a normal pressure gas has a significantly low energy density per unit volume. Methanol and ethanol require one molecule and three molecules of water for the oxidation reaction (see the following formula), but it is clear that liquid fuel is excellent even when this is taken into account.

CH ₃ OH + H ₂ O → 6H ⁺ + 6e ⁻ + CO ₂
C ₂ H ₅ OH + 3H ₂ O → 12H ⁺ + 12e ⁻ + 2CO ₂
Although it is possible to use high-pressure hydrogen or liquid hydrogen, it is necessary to make the container robust, and considering the energy density of the container, liquid or solid fuel at room temperature and normal pressure is excellent. Yes. Specifically, hydrogen stored in the hydrogen storage alloy, solid fuel such as gasoline, liquid hydrocarbon, liquid alcohol, or liquid fuel can be used, but the main fuel cell can be downsized, volume energy From the viewpoint of excellent density, it is preferable to use an alcohol fuel. By using alcohol fuel, a portable fuel cell 1 with improved driving time can be formed. Among these, it is preferable to use an alcohol having 4 or less carbon atoms, and it is particularly preferable to use ethanol from the viewpoint of high safety and biosynthesis (environmental aspect).

<Example 1>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared. Three first deformable members 15 made of polyurethane (pore diameter: 5 to 7 μm, porosity: 80%) having a thickness of 1.6 mm are placed on the sample stage 11 of the pressurizing apparatus 10, and the laminate 8 is placed thereon. 1 set. Thereafter, the same first deformable member 15 is placed thereon, another stack of stacked bodies 8 is placed thereon, and the same first deformable member 15 is further placed thereon. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, a nitrogen gas cylinder is connected to the joint 21. Here, the nitrogen gas becomes the pressurized medium A.

  Next, the valve 20 is opened in such a state. Nitrogen gas is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizer 10, and the second deformable member 16 made of silicon rubber swells toward the laminate 8, and the laminate 8. Pressurize. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Uniform pressurization is performed at all points where the second deformable member 16 is in contact, and the obtained joined body 8a composed of the solid electrolyte membrane 3a and the electrode 4 includes the electrode 4 (laminated portion) and the electrode 4. It was confirmed that wrinkles due to distortion did not occur in the peripheral part of.

<Example 2>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared. Three first deformable members 15 made of polyurethane having a thickness of 1.6 mm (pore diameter: 5 to 7 μm, porosity: 80%) are placed on the sample table 11 of the pressurizing apparatus 10, and foam PET is used on the first deformable member 15. The first deformable member 15 to be formed is placed on top of each other, and one set of the laminated bodies 8 is placed thereon. Further, a first deformable member 15 made of foamed PET, a first deformable member 15 made of similar polyurethane, and a first deformable member 15 made of foamed PET are placed on top of each other in this order, and the laminate is already placed on it. Stack one set. And the 1st deformation member 15 which consists of foaming PET, and the 1st deformation member 15 which consists of the same polyurethane are piled up in that order on it. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, a nitrogen gas cylinder is connected to the joint 21. Here, the nitrogen gas becomes the pressurized medium A.

  Next, the valve 20 is opened in such a state. Nitrogen gas is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizer 10, and the second deformable member 16 made of silicon rubber swells toward the laminate 8, and the laminate 8. Pressurize. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Uniform pressurization is performed at all points where the second deformable member 16 is in contact, and the obtained joined body 8a composed of the solid electrolyte membrane 3a and the electrode 4 includes the electrode 4 (laminated portion) and the electrode 4. It was confirmed that wrinkles due to distortion did not occur in the peripheral part of.

<Example 3>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared. A first deformable member 15 made of silicon rubber having a thickness of 0.5 mm is placed on the sample table 11 of the pressurizing device 10, and a sliding member 24 subjected to paraffin processing is superimposed on the paper base surface. Then, one set of the laminates 8 is stacked thereon. Further, the same sliding member 24, the same first deformation member 15 and the same sliding member 24 are stacked in that order, and another layered product 8 is stacked thereon. And the same sliding member 24 and the same 1st deformation member 15 are piled up and installed in that order on it. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, a nitrogen gas cylinder is connected to the joint 21. Nitrogen gas becomes the pressurized medium A.

  Next, the valve 20 is opened in such a state. Nitrogen gas is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizer 10, and the second deformable member 16 made of silicon rubber swells toward the laminate 8, and the laminate 8. Pressurize. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Uniform pressurization is performed at all points where the second deformable member 16 is in contact, and the obtained joined body 8a composed of the solid electrolyte membrane 3a and the electrode 4 includes the electrode 4 (laminated portion) and the electrode 4. It was confirmed that wrinkles due to distortion did not occur in the peripheral part of.

<Example 4>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared.

  Three first deformable members 15 made of polyurethane having a thickness of 1.6 mm (pore diameter 5 to 7 μm, porosity 80%) are placed on the sample table 11 of the pressurizing apparatus 10, and a paper base is placed thereon. A sliding member 24 that has been subjected to paraffin treatment is placed on the surface of the material, and one set of the laminates 8 is placed thereon. Further, the same sliding member 24, the same first deformation member 15 and the same sliding member 24 are stacked in that order, and another layered product 8 is stacked thereon. And the same sliding member 24 and the same 1st deformation member 15 are piled up and installed in that order on it. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, a nitrogen gas cylinder is connected to the joint 21. Nitrogen gas becomes the pressurized medium A.

  Next, the valve 20 is opened in such a state. Nitrogen gas is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizer 10, and the second deformable member 16 made of silicon rubber swells toward the laminate 8, and the laminate 8. Pressurize. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Uniform pressurization is performed at all points where the second deformable member 16 is in contact, and the obtained joined body 8a composed of the solid electrolyte membrane 3a and the electrode 4 includes the electrode 4 (laminated portion) and the electrode 4. It was confirmed that wrinkles due to distortion did not occur in the peripheral part of.

<Example 5>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared. Three first deformable members 15 made of polyurethane having a thickness of 1.6 mm (pore diameter: 5 to 7 μm, porosity: 80%) are placed on the sample table 11 of the pressurizing apparatus 10, and foam PET is used on the first deformable member 15. The first deformable member 15 to be formed is placed on top of each other, and one set of the laminated bodies 8 is placed thereon. Furthermore, a first deformable member 15 made of foamed PET, a first deformable member 15 made of similar polyurethane, and a first deformable member 15 made of foamed PET are placed in this order on top of each other. Stack one set. And the 1st deformation member 15 which consists of foaming PET, and the 1st deformation member 15 which consists of the same polyurethane are piled up in that order on it. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, the air compressor is connected to the joint 21. Here, air becomes the pressurized medium A.

  Next, the air compressor is operated in such a state to open the valve 20. Air is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizing device 10, and the second deformable member 16 made of silicon rubber swells to the laminated body 8 side, and the laminated body 8 is Pressurize. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Uniform pressurization is performed at all points where the second deformable member 16 is in contact, and the obtained joined body 8a composed of the solid electrolyte membrane 3a and the electrode 4 includes the electrode 4 (laminated portion) and the electrode 4. It was confirmed that wrinkles due to distortion did not occur in the peripheral part of.

<Comparative Example 1>
First, two sets of laminates 8 in which electrodes (carbon electrodes) 4 to which carbon carrying a catalyst is attached are arranged on both sides of a solid electrolyte membrane (Nafion 115, manufactured by Dupont) 3a are prepared. The stacked body 8 is placed on the sample stage 11 of the pressure device 10. Subsequently, the gap between the flat plate 12 and the flat plate 13 of the pressure device 10 is set to a predetermined gap by the gap member 14. Then, a nitrogen gas cylinder is connected to the joint 21. Here, the nitrogen gas becomes the pressurized medium A.

  Next, the valve 20 is opened in such a state. Nitrogen gas is supplied between the flat plate 13 and the second deformable member 16 from the pressurized medium supply port 18 of the pressurizer 10, and the second deformable member 16 made of silicon rubber swells toward the laminate 8, and the laminate 8. Pressurize directly. When the pressure gauge 22 reaches 50 atm, the valve 20 is closed and the pressurized state is maintained for 1 hour.

  In this way, two sets of joined bodies 8a were formed. Although the surface of the joined body 8a on the sample stage 11 side was less wrinkled, it was confirmed that wrinkles were generated in the periphery of the electrode 4 on the surface on the pressure side (second deformation member 16 side). It was done.

It is explanatory drawing for demonstrating the electric power generation concept of a fuel cell. It is a center longitudinal section side view showing roughly the pressurization device of one embodiment of the present invention. It is a top view which shows roughly the pressurization apparatus of one Embodiment of this invention. It is a center longitudinal cross-sectional side view which shows the pressurization apparatus of a pressurization state roughly. It is a vertical side view which shows roughly the laminated body on which the 1st deformation member and the sliding member were laminated | stacked.

Explanation of symbols

1 Fuel cell 3a Electrolyte membrane (solid electrolyte membrane)
4 Electrode 8 Laminate 8a Joint 11 Mounting Base 15 First Deformation Member 16 Second Deformation Member A Pressure Medium

Claims (15)

Laminating a laminated body having a solid electrolyte membrane and an electrode sandwiching the solid electrolyte membrane, and a first deformable member sandwiching the laminated body and deformable by an external force on the mounting table;
An external force is applied to the second deformable member that can be deformed by an external force by a pressure medium, the second deformable member is deformed, and brought into contact with the first deformable member stacked on the mount table. Pressurizing the laminated first deformable member and the laminated body in the lamination direction;
A method for producing a solid electrolyte membrane and electrode assembly.   The method for producing a joined body of a solid electrolyte membrane and an electrode according to claim 1, wherein the step of laminating the laminate and the first deformable member comprises laminating the plurality of laminates and the plurality of first deformable members.   3. The method for manufacturing a joined body of a solid electrolyte membrane and an electrode according to claim 1, wherein the first deformable member is a member that is less deformed in a direction perpendicular to the pressurizing direction than deformed in the pressurizing direction.   4. The method for producing a joined body of a solid electrolyte membrane and an electrode according to claim 1, wherein the first deformable member is a porous body formed of a porous material.   The step of laminating the laminate and the first deformable member comprises the step of laminating a sliding member for improving slippage between the laminate and the first deformable member. A method for producing a joined body of a solid electrolyte membrane and an electrode according to 3 or 4.   The solid electrolyte membrane according to claim 5, wherein the sliding member is a member having flexibility, and an elongation rate in a direction perpendicular to a pressing direction is smaller than an elongation rate in a direction perpendicular to the pressing direction of the first deformation member. And a method for producing an electrode assembly.   The solid electrolyte membrane / electrode assembly according to claim 5 or 6, wherein the sliding member includes a base material having a lower elongation rate than the first deformation member and a sliding layer provided on a surface of the base material. Manufacturing method.   The method for producing a joined body of a solid electrolyte membrane and an electrode according to any one of claims 1 to 7, wherein the pressurizing medium is a gas.   The method for producing a solid electrolyte membrane / electrode assembly according to claim 8, wherein the gas is air.   The method for producing a joined body of a solid electrolyte membrane and an electrode according to any one of claims 1 to 7, wherein the pressurizing medium is a liquid.   The method for producing a joined body of a solid electrolyte membrane and an electrode according to any one of claims 1 to 10, further comprising a step of heating the laminated body laminated on the mounting table.   A solid electrolyte membrane / electrode assembly manufactured by the method for manufacturing a solid electrolyte membrane / electrode assembly according to claim 1.   13. A fuel cell comprising the solid electrolyte membrane and electrode assembly according to claim 12 and generating electric power from fuel supplied to the assembly.   The fuel cell according to claim 13, wherein the fuel is a fuel containing alcohol.   The fuel cell according to claim 14, wherein the alcohol is ethanol.

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