JP2009211977A - Fuel cell and cell unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve assembling properties and/or disassembling properties of a fuel cell. <P>SOLUTION: In the fuel cell having a constitution that cell units are stacked, the cell units include a separator, a stacking structure arranged on a first region on the separator and including an electrolyte membrane and two electrode layers, and a sealing member. The sealing member has an end sealing part adhered to a second region to surround the first region in the separator and integrated with the end of the stacked structure, a rib contacting with the second separator formed on the end sealing part, and a protrusion formed on the end sealing part and arranged at least on one of the outside and inside of the rib. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cell and a battery unit.

  In a fuel cell, for example, a polymer electrolyte fuel cell, a reactive gas (a fuel gas containing hydrogen and an oxidizing gas containing oxygen) is respectively applied to two electrodes (a fuel electrode and an oxygen electrode) facing each other with an electrolyte membrane interposed therebetween. By supplying and performing an electrochemical reaction, the chemical energy of the substance is directly converted into electrical energy. The main structure of such a fuel cell is a so-called stack structure in which a laminate including a substantially flat membrane electrode assembly (MEA) and a separator are alternately laminated and fastened in the lamination direction. It has been known.

  By the way, as a fuel cell having the above-described stack structure, a technique for joining a seal member to an end portion of a membrane electrode assembly is known (for example, Patent Document 1). Further, a technique for integrally forming a separator, a gas diffusion layer, and a seal member is known (for example, Patent Document 2). In these technologies, mixing of fuel gas, oxidizing gas, and cooling medium and leakage to the outside are suppressed by this seal member.

JP 2003-157867 A International Publication WO02 / 001658 JP 2005-285423 A JP 2007-87865 A

  However, in the above prior art, it cannot be said that assembly and disassembly of the fuel cell stack are sufficiently easy. For example, when assembling, in the technique of integrally forming the seal member at the end of the membrane electrode assembly, it is necessary to alternately stack separators and membrane electrode assemblies.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to improve the assembling property and / or the decomposing property of a fuel cell having a stack structure.

  The present invention can be realized as the following forms or application examples in order to solve at least a part of the above-described problems.

Application Example 1 A fuel cell including a plurality of stacked battery units,
The battery unit is
A separator;
A laminated structure disposed in a first region on the separator and including an electrolyte membrane and two electrode layers;
A sealing member;
With
The sealing member is
An end seal portion bonded to a second region surrounding the first region of the separator and integrated with an end portion of the laminated structure;
A sealing rib formed on the upper surface of the end seal portion;
A convex portion formed on the upper surface of the end seal portion and disposed on at least one of the outer side and the inner side of the sealing rib;
A fuel cell.
By so doing, the fuel cell can be configured by stacking the battery unit in which the separator, the seal member, and the stacked structure are integrated, so that the assembly of the fuel cell can be improved. Moreover, the short circuit between battery units can be suppressed by arrange | positioning a convex-shaped part.

Application Example 2 In the fuel cell according to claim 1,
The sealing rib is disposed so as to surround the laminated structure,
The said convex-shaped part is a fuel cell arrange | positioned on the outer side of the said rib for sealing.

[Application Example 3]
In the fuel cell according to Application Example 1 or Application Example 2,
The height of the convex part in the stacking direction is a fuel cell lower than the height of the sealing rib in the stacking direction.
If it carries out like this, it can suppress that a convex-shaped part disturbs the sealing performance of the rib for sealing.

[Application Example 4] In the fuel cell according to any one of Application Examples 1 to 3,
The fuel cell, wherein the end seal portion and the second region are bonded with a bonding force that does not cause a displacement due to a fluid pressure assumed during operation of the fuel cell.
If it carries out like this, the fastening force which fastens a fuel cell required for ensuring sealing performance in a lamination direction can be reduced.

[Application Example 5] In the fuel cell according to any one of Application Examples 1 to 4,
The laminated structure further includes a gas diffusion layer disposed on both surfaces of the electrolyte membrane with the electrode layer interposed therebetween.
In this way, the gas diffusion layer can be integrated with the battery unit, so that the assemblability is further improved.

[Application Example 6]
In the fuel cell according to Application Example 5,
The laminated structure further includes a porous body disposed on both surfaces of the electrolyte membrane with the electrode layer and the diffusion layer interposed therebetween.
In this way, the porous body can be integrated with the battery unit, so that the assemblability is further improved.

  Furthermore, the present invention can be implemented in various other ways. For example, the present invention relates to a vehicle equipped with the fuel cell, a device invention such as a moving body that moves using the fuel cell as a power source, a method for manufacturing a battery unit, and a method for manufacturing a fuel cell including a plurality of stacked cell units. It can be realized as a method invention.

A. First embodiment:
FIG. 1 is an explanatory diagram showing the configuration of a fuel cell as one embodiment of the present invention. The fuel cell 100 has a structure in which a plurality of battery units 200 are stacked. The fuel cell 100 is manufactured by stacking a predetermined number of battery units 200 and fastening the stacked battery units 200 so as to load a predetermined fastening force in the stacking direction.

  The fuel cell 100 includes an oxidizing gas supply manifold 110 that is supplied with oxidizing gas, an oxidizing gas discharge manifold 120 that discharges oxidizing gas, a fuel gas supply manifold 130 that is supplied with fuel gas, and a fuel that discharges fuel gas. A gas discharge manifold 140, a cooling medium supply manifold 150 for supplying a cooling medium, and a cooling medium discharge manifold 160 for discharging the cooling medium are provided. Note that air is generally used as the oxidizing gas, and hydrogen is generally used as the fuel gas. Further, both the oxidizing gas and the fuel gas are also called reaction gases. As the cooling medium, water, antifreeze water such as ethylene glycol, air, or the like can be used.

  FIG. 2 is a front view of the battery unit 200. FIG. 3 is a view showing a cross section taken along line AA in FIG. The battery unit 200 includes a separator 600, a stacked structure 800, and a seal member 700.

  The laminated structure 800 includes an MEA (Membrane Electrode Assembly) 810, an anode side diffusion layer 820 disposed in contact with the anode side surface of the MEA 810, and a cathode side diffusion layer 830 disposed in contact with the cathode side surface of the MEA 810. And an anode-side porous body 840 and a cathode-side porous body 850. The anode side porous body 840 is disposed on the anode side of the MEA 810 with the anode side diffusion layer 820 interposed therebetween, and the cathode side porous body 850 is disposed on the cathode side of the MEA 810 with the cathode side diffusion layer 830 interposed therebetween. The cathode-side porous body 850 is in contact with the separator 600. The anode-side porous body 840 contacts the surface of the separator 600 of the other battery unit 200 on the anode plate 300 side when the plurality of battery units 200 are stacked to form the fuel cell 100.

  The MEA 810 is composed of, for example, an electrolyte membrane made of a fluorine-based resin material or a hydrocarbon-based resin material and having good ionic conductivity in a wet state, and electrode layers (anode and cathode) applied to both surfaces thereof. ing. The electrode layer is, for example, a catalyst layer containing platinum or an alloy made of platinum and another metal.

  The anode side diffusion layer 820 and the cathode side diffusion layer 830 are formed of, for example, carbon cloth woven with yarns made of carbon fibers, carbon paper, or carbon felt.

  The anode side porous body 840 and the cathode side porous body 850 are formed of a porous material having gas diffusibility and conductivity such as a metal porous body. The anode-side porous body 840 and the cathode-side porous body 850 have a higher porosity than the anode-side diffusion layer 820 and the cathode-side diffusion layer 830 described above, and the gas flow resistance therein is the anode-side diffusion layer 820 and the cathode-side diffusion layer. Those below 830 are used and function as a flow path for the reaction gas to flow as will be described later.

  The separator 600 includes an anode plate 300, a cathode plate 400, and an intermediate plate 500.

  FIG. 4 is a diagram showing the shape of the cathode plate 400. A region DA indicated by a broken line in the central portion of the cathode plate 400 is a region (hereinafter referred to as a power generation region DA) in the battery unit 200 in which the above-described stacked structure 800 is disposed. On the cathode plate 400, a region RA surrounding the entire circumference of the power generation region DA is a region to which the seal member 700 is bonded (hereinafter referred to as a seal region RA). In FIG. 4, the seal area RA is indicated by hatching.

  The cathode plate 400 is made of stainless steel, for example. The cathode plate 400 includes six manifold forming portions 422 to 432, an oxidizing gas supply slit 440, and an oxidizing gas discharge slit 444. The manifold forming portions 422 to 432 are through portions for forming the various manifolds described above when configuring the fuel cell 100, and are respectively provided outside the power generation area DA. The oxidizing gas supply slit 440 is disposed at the end (the upper end in FIG. 4) of the power generation area DA. The oxidizing gas discharge slit 444 is arranged side by side at the end of the power generation area DA (the lower end in FIG. 4).

  FIG. 5 is a diagram showing the shape of the anode plate 300. Similar to FIG. 4, in FIG. 5, a power generation area DA in which the above-described stacked structure 800 is arranged in the battery unit 200 is illustrated in the center portion of the anode plate 300. The anode plate 300 is formed of stainless steel, for example, like the cathode plate 400. Similar to the cathode plate 400, the anode plate 300 includes six manifold forming portions 322 to 332, a fuel gas supply slit 350, and a fuel gas discharge slit 354. The manifold forming portions 322 to 332 are through portions for forming the various manifolds described above when configuring the fuel cell 100, and are provided outside the power generation area DA, similarly to the cathode plate 400. The fuel gas supply slit 350 is arranged at the end (lower end in FIG. 5) of the power generation area DA so as not to overlap the above-described oxidizing gas discharge slit 444 in the cathode plate 400 when the separator 600 is configured. The fuel gas discharge slit 354 is arranged at the end (the upper end in FIG. 5) of the power generation area DA so as not to overlap the above-described oxidizing gas supply slit 440 in the cathode plate 400 when the separator 600 is configured.

  FIG. 6 is a diagram illustrating the shape of the intermediate plate 500. The intermediate plate 500 is made of, for example, stainless steel, like the above-described plates 300 and 400. The intermediate plate 500 has four manifold forming portions 522 to 528 for supplying / discharging the reaction gas (oxidizing gas or fuel gas) as feed-through portions penetrating in the thickness direction, supply flow path forming portions 542 and 546, and Discharge flow path forming portions 544 and 548 are provided. The intermediate plate 500 further includes a plurality of cooling medium flow path forming portions 550. The manifold forming portions 522 to 528 are through portions for forming the various manifolds described above when configuring the fuel cell 100, and are provided outside the power generation area DA, similarly to the cathode plate 400 and the anode plate 300. ing.

  Each cooling medium flow path forming portion 550 has a long hole shape that crosses the power generation area DA in the left-right direction in FIG. 6, and both ends thereof reach the outside of the power generation area DA. The cooling medium flow path forming portions 550 are arranged in parallel in the vertical direction in FIG.

  Reactive gas supply flow path forming portions 542 and 546 and discharge flow path forming portions 544 and 548 are respectively connected at one end to corresponding manifold forming portions 522 to 528. The other ends of these flow path forming portions 542 to 548 communicate with the corresponding gas supply / discharge slits 350, 354, 440, and 444 when the three plates are joined.

  FIG. 7 is a front view of the separator 600. The separator 600 joins the above-described anode plate 300 and cathode plate 400 to both sides of the intermediate plate 500 so as to sandwich the intermediate plate 500, and corresponds to the cooling medium supply manifold 150 and the cooling medium discharge manifold 160 in the intermediate plate 500. This is produced by punching the exposed part in the area to be processed. As a method of joining the three plates, for example, thermocompression bonding, brazing, welding, or the like can be used. As a result, the six manifolds 110 to 160, which are through portions indicated by hatching in FIG. 7, the oxidizing gas supply flow path 650, the oxidizing gas discharge flow path 660, the fuel gas supply flow path 630, and the fuel gas discharge flow path Separator 600 including 640 and cooling medium flow path 670 is manufactured.

  As shown in FIGS. 2 and 3, a seal member 700 is disposed in the seal region RA on the surface of the separator 600 on the cathode plate 400 side described above. The seal member 700 is formed of a material having gas impermeability, elasticity, and heat resistance in the operating temperature range of the fuel cell, for example, an elastic material such as rubber or elastomer. Specifically, silicon rubber, butyl rubber, acrylic rubber, natural rubber, fluorine rubber, ethylene / propylene rubber, styrene elastomer, fluorine elastomer and the like can be used.

  The seal member 700 includes a support portion 710, a sealing rib 720, and a short-circuit suppressing rib 730. The sealing rib 720 and the short-circuit suppressing rib 730 are formed on the upper portion of the support portion 710.

  The support portion 710 of the seal member 700 is in contact with the entire seal region RA described above. A contact surface SU (FIG. 2: thick line) between the support portion 710 and the surface of the cathode plate 400 is bonded with a predetermined bonding force.

  Here, the predetermined bonding force is a bonding force in a state where the battery unit 200 is not fastened in the stacking direction, that is, a state where no load in the stacking direction is applied. The predetermined bonding force is such that when the fluid pressure assumed during the operation of the fuel cell is loaded on the seal member 700 as shown by an arrow in FIG. The coupling force does not shift in the direction along the contact surface SU. The fluid pressure assumed during the operation of the fuel cell is supplied to the fuel gas pressure, the oxidizing gas pressure, the cooling medium pressure in the manifolds 110 to 160, and the cathode side diffusion layer 830 and the cathode side porous body 850. The pressure of the oxidizing gas and the pressure of the fuel gas supplied to the anode side diffusion layer 820 and the anode side porous body 840 are provided.

  The predetermined binding force is preferably determined based on the maximum fluid pressure assumed. For example, the pressure of the oxidizing gas, the fuel gas, and the cooling medium increases as the fuel cell is operated at a higher load. Further, when the fluid flows, pressure loss occurs, so that the pressure on the upstream side (inlet side) of the flow path is higher than that on the downstream side (outlet side). When air is used as the oxidizing gas, only about 20% of the oxygen used in the electrochemical reaction is contained in the air, so the oxidizing gas is supplied at a high pressure to supply sufficient oxygen to the cathode. There are many cases to do. Further, when the generated water is to be discharged outside using the flow of the oxidizing gas, the oxidizing gas is often supplied at a high pressure in order to efficiently discharge the generated water. Therefore, in such a case, the contact surface SU is coupled so that there is no deviation with respect to the pressure on the upstream side (near the oxidizing gas supply manifold 110) of the oxidizing gas flow path during high load operation. The power is determined.

  Specifically, the bonding force of the contact surface SU is preferably 0.01 N / mm (Newtons per millimeter) or more, more preferably 0.6 N / mm or more per unit length of the seal line.

  The support portion 710 is integrated by impregnating the end portion of the laminated structure 800 as indicated by reference numeral BB. Thereby, leakage of the reaction gas from the cathode side to the anode side of the MEA 810 or from the anode side to the cathode side is suppressed at the end of the laminated structure 800.

  As shown in FIG. 2, the sealing rib 720 is formed so as to surround the laminated structure 800 and the manifolds 110 to 160. When the battery units 200 are stacked to constitute the fuel cell 100, the sealing rib 720 comes into airtight contact with the anode plate 300 of the separator 600 of the other battery unit 200 by the fastening force in the stacking direction.

  As understood from the above description, the seal member 700 seals the space between the battery unit 200 and the separator 600 of the battery unit 200 by the contact surface SU of the support unit 710 when the battery unit 200 is stacked and constitutes the fuel cell 100. A gap between the separators 600 of the adjacent battery units 200 is sealed with a sealing rib 720. Thereby, mixing of fuel gas, oxidizing gas, and cooling medium and leakage to the outside are suppressed.

  The short-circuit suppressing rib 730 is provided along the outer peripheral edge of the support portion 710. The short-circuit suppressing rib 730 is provided outside the sealing rib 720. The short-circuit suppressing rib 730 is provided in the vicinity of each of the manifolds 110 to 160 along a portion along the outer peripheral edge of the sealing rib 720 surrounding the manifold.

  The height of the short-circuit suppressing rib 730 in the stacking direction is set lower than that of the sealing rib 720. Thereby, when assembled accurately as designed and the separators 600 are kept parallel to each other, the short-circuit suppressing rib 730 is not in contact with the anode plate 300 of the upper battery unit 200. The short-circuit suppressing rib 730 may be in contact with the anode plate 300 at a pressure lower than the contact pressure between the sealing rib 720 and the anode plate 300.

  FIG. 8 is an explanatory diagram showing the flow of the oxidizing gas in the fuel cell. In order to make the figure easy to see, FIG. 8 illustrates a state in which two battery units 200 are stacked. FIG. 8 shows a cross section corresponding to the BB cross section in FIG.

  The fuel cell 100 generates power by supplying the oxidizing gas to the oxidizing gas supply manifold 110 and supplying the fuel gas to the fuel gas supply manifold 130. In addition, the cooling medium is supplied to the cooling medium supply manifold 150 in order to suppress the temperature rise of the fuel cell 100 due to heat generated by power generation.

The oxidant gas supplied to the oxidant gas supply manifold 110 is supplied from the oxidant gas supply manifold 110 to the cathode-side porous body 850 through the oxidant gas supply channel 650 as indicated by arrows in FIG. The oxidizing gas supply channel 650 is formed by the oxidizing gas supply channel forming part 542 (FIG. 6) formed in the intermediate plate 500 and the oxidizing gas supply slit 440 (FIG. 4) formed in the cathode plate 400. The The oxidizing gas supplied to the cathode side porous body 850 flows from the upper side to the lower side in FIG. 2 in the cathode side porous body 850 functioning as a flow path for the oxidizing gas. Then, the oxidizing gas is discharged to the oxidizing gas discharge manifold 120 through the oxidizing gas discharge channel 660. The oxidizing gas discharge channel 660 is formed by the oxidizing gas discharge channel forming part 544 (FIG. 6) formed in the intermediate plate 500 and the oxidizing gas discharge slit 444 (FIG. 4) formed in the cathode plate 400. The A part of the oxidizing gas flowing through the cathode side porous body 850 diffuses over the entire cathode side diffusion layer 830 in contact with the cathode side porous body 850 and causes a cathode reaction (for example, 2H ⁺ + 2e ⁻ + (1 / 2) Used for O ₂ → H ₂ O).

FIG. 9 is an explanatory diagram showing the flow of fuel gas in the fuel cell. 9 shows a cross section corresponding to the broken line CC in FIG. 7, and the lower part of FIG. 9 shows a cross section corresponding to the broken line DD in FIG. The fuel gas supplied to the fuel gas supply manifold 130 is supplied from the fuel gas supply manifold 130 to the anode-side porous body 840 through the fuel gas supply flow path 630 as indicated by arrows in the lower part of FIG. The fuel gas supply channel 630 is formed by the fuel gas supply channel forming part 546 (FIG. 6) formed in the intermediate plate 500 and the fuel gas supply slit 350 (FIG. 5) formed in the anode plate 300. The The fuel gas supplied to the anode side porous body 840 flows from the lower side to the upper side in FIG. 2 in the anode side porous body 840 functioning as a fuel gas flow path. Then, the fuel gas is discharged to the fuel gas discharge manifold 140 through the fuel gas discharge channel 640. The fuel gas discharge flow path 640 is formed by the fuel gas discharge flow path forming portion 548 (FIG. 6) formed in the intermediate plate 500 and the fuel gas discharge slit 354 (FIG. 5) formed in the anode plate 300. The A part of the oxidizing gas flowing through the anode-side porous body 840 diffuses over the entire anode-side diffusion layer 820 in contact with the anode-side porous body 840, and the anode reaction (for example, H ₂ → 2H ⁺ + 2e ⁻ ).

  The cooling medium supplied to the cooling medium supply manifold 150 is supplied from the cooling medium supply manifold 150 to the cooling medium flow path 670. As shown in FIG. 7, the cooling medium flow path 670 is formed by the cooling medium flow path forming portion 550 (FIG. 6) formed in the above-described intermediate plate 500, one end being the cooling medium supply manifold 150 and the other end being the other end. It communicates with the cooling medium discharge manifold 160. The cooling medium supplied to the cooling medium flow path 670 flows from one end of the cooling medium flow path 670 to the other end, and is discharged to the cooling medium discharge manifold 160.

-Manufacturing method of battery unit 200:
FIG. 10 is a diagram for explaining the manufacture of the battery unit in the first embodiment. The mold for integral molding has an upper mold 910 and a lower mold 920. The lower mold 920 is formed with a protruding portion PJ that fits into the manifolds 110 to 160 of the separator 600 when the separator 600 is disposed. The upper mold 910 has a molding material inlet SH formed above the protrusion PJ of the lower mold 920.

  In the manufacturing process, the separator 600 is disposed in the lower mold 920 with the anode plate 300 side facing downward and the cathode plate 400 side facing upward. A cathode-side porous body 850 is disposed on the separator 600 disposed in the lower mold 920. The cathode-side porous body 850 is disposed in the power generation area DA on the surface of the separator 600 on the cathode plate 400 side.

  The MEGA 860 and the anode side porous body 840 are sequentially arranged so as to overlap the arranged cathode side porous body 850. The MEGA 860 is obtained by integrally bonding an anode side diffusion layer 820 and a cathode side diffusion layer 830 to both surfaces of the above-described MEA 810 by hot pressing in advance.

  Thus, when all the laminated structures 800 are arranged in the power generation area DA of the separator 600, the mold is clamped with a predetermined mold pressure, and injection molding is performed. FIG. 10B shows a state where the lower mold 920 and the upper mold 910 are clamped. In the clamped state, a space SP having the shape of the seal member 700 is formed above the seal region RA on the cathode plate 400. As shown in FIG. 10B, the space SP includes the surface of the cathode plate 400, the inner wall surfaces of the lower mold 920 and the upper mold 910, and the laminated structure 800 (the anode side porous body 840, the MEGA 860, and the cathode side porous body). 850). Injection molding is performed in this space SP. Specifically, after the liquid rubber as the molding material of the seal member 700 is introduced into the space SP from the above-described inlet SH, the vulcanization process is performed.

  In this injection molding, when the molding material is impregnated into the end of the laminated structure 800 (region BB in FIGS. 2 and 3), the injection pressure of the molding material is set so that the laminated structure 800 and the seal member 700 are integrated. Be controlled. Further, by adding a silane coupling agent to the molding material, the bonding force between the contact surface SU (FIG. 3) of the seal member 700 and the separator 600 is ensured. After the injection molding, the mold is opened to obtain the battery unit 200.

  According to the present embodiment described above, the battery unit 200 in which the seal member 700, the separator 600, and the laminated structure 800 are integrated is manufactured, and the fuel cell 100 is manufactured by stacking and fastening the battery units 200. Therefore, the assembling property of the fuel cell 100 can be improved and the manufacturing process can be reduced.

  Furthermore, in the present embodiment, since the short-circuit suppressing rib 730 is provided on the seal member 700, it is possible to prevent the separators 600 of the battery units 200 adjacent to each other from being short-circuited. As a result, it is possible to suppress a decrease in the power generation capability of the fuel cell due to a short circuit.

  FIG. 11 is a diagram showing a fuel cell in a comparative example. The fuel cell according to the comparative example is different from the fuel cell according to the first embodiment in that the seal member 700a has no short-circuit suppressing rib. Other configurations are the same as those of the first embodiment. For convenience of illustration, the tip in the cooling medium discharge manifold 160 is omitted. In the fuel cell in the comparative example, when a part of the battery unit 200a is displaced in the direction (plane direction) perpendicular to the stacking direction, the end portions of the separators 600 of the battery units 200 adjacent to each other may be short-circuited. In particular, the space between each manifold and the outer peripheral end is preferably thin from the viewpoint of miniaturization of the fuel cell stack. However, if this portion is thin, the separator 600 is likely to be broken as shown in FIG. 11 due to insufficient rigidity, and as a result, a short circuit between the separators 600 is likely to occur.

  FIG. 12 is a diagram illustrating a state in which the battery unit is displaced in the first embodiment. In the fuel cell 100 according to the first embodiment, when a part of the battery unit 200 is displaced in the surface direction, the separator 600 is broken as in the comparative example, but the short-circuit suppressing rib 730 of the one battery unit 200 has When the separator 600 of the other battery unit 200 stacked thereon is brought into contact, the amount of folding of the separator 600 is suppressed. As a result, as described above, a short circuit between the separators 600 is suppressed.

  Further, since the seal member 700 is in surface contact with the highly rigid separator 600 and supported in its shape, deformation of the seal member 700 during lamination and fastening is suppressed, and accurate assembly is realized.

  Furthermore, the fastening force in the stacking direction of the fuel cell 100 can be reduced. As a result, the fastening member that fastens the fuel cell 100 in the stacking direction can be reduced in size, the separator 600 can be thinned, and the fuel cell 100 can have a long life. That is, as described above, the contact surface SU between the seal member 700 and the separator 600 has a binding force that can withstand the fluid pressure assumed during operation of the fuel cell in a state where no force is applied in the stacking direction. is doing. Therefore, the fastening force in the stacking direction of the fuel cell 100 may be determined in consideration of ensuring the sealing performance between the rib 720 and the separator 600 without considering the suppression of the displacement of the seal member 700. As a result, the fastening force in the stacking direction of the fuel cell 100 can be greatly reduced.

B. Second embodiment:
FIG. 13 is a diagram showing the configuration of the fuel cell in the second embodiment. The fuel cell seal member 700 in the first embodiment described above includes the short-circuit suppressing rib 730 outside the seal rib 720 that surrounds the power generation area DA and each manifold, but the fuel cell seal member in the second embodiment. 700b includes a short-circuit suppressing rib 730b inside a sealing rib 720b surrounding the manifold. Other configurations are the same as those of the fuel cell in the first embodiment.

  The short-circuit suppressing rib 730b of the second embodiment can suppress a short circuit between the separators 600 adjacent to each other, similarly to the short-circuit suppressing rib 730 of the first embodiment.

C. Third embodiment:
FIG. 14 is a diagram showing the configuration of the fuel cell in the third embodiment. Instead of the short-circuit suppressing rib 730 provided on the seal member 700 of the fuel cell in the first embodiment described above, a plurality of short-circuit suppressing protrusions 730c are provided. The short-circuit suppressing protrusion 730c has a rectangular shape when viewed from the stacking direction. The short-circuit suppressing protrusions 730 c are arranged at equal intervals along the sealing rib 720.

  In the fuel cell seal member 700 in the first embodiment described above, the short-circuit suppressing rib 730 is provided over the entire outer periphery of the support portion 710. In the fuel cell seal member 700c in the third embodiment, Of the outer peripheral edge of the support portion 710, a short-circuit suppressing protrusion 730c is provided at a portion where the manifolds 110 to 160 are disposed on the inner side. As described above, the short-circuit suppressing rib may be provided on a part of the inside or outside of the sealing rib 720 as necessary.

D. Variations:
・ First modification:
In the third embodiment, the shape of the short-circuit suppressing protrusion 730c viewed from the stacking direction is a rectangle. However, instead of this, a circle, a square, a triangle, or a pentagon may be used. Other polygons may be used.

・ Second modification:
In the above-described embodiment, the silane coupling agent is added to the seal member 700 to secure the bonding force of the contact surface SU (FIG. 5) between the seal member 700 and the separator 600. May be secured by various other methods. For example, intermolecular forces, chemical bonds such as covalent bonds and hydrogen bonds, and physical bonds such as mechanical bonds may be used. More specifically, as the chemical bond, various adhesives such as a primer treatment and an epoxy type can be used in addition to the silane coupling agent in the embodiment. The primer treatment and the adhesive may be applied to the separator 600 in addition to being added to the molding material. As the physical coupling, a suction cup effect obtained by bringing the contact surface SU of the seal member 700 and the separator 600 into close contact and creating a vacuum can be used.

・ Third modification:
In the above embodiment, the battery unit 200 in which the laminated structure 800 and the seal member 700 are integrated is used on the surface of the separator 600 on the cathode plate 400 side, but instead, on the surface of the separator 600 on the anode plate 300 side. The laminated structure 800 and the seal member 700 may be integrated.

-Fourth modification:
In the above embodiment, the seal member 700 is formed by injection molding, but instead, the seal member 700 may be formed by compression molding. For example, heat vulcanization compression molding is used in which a solid unvulcanized rubber is filled in the mold space SP, the mold is clamped and heated, and the shape is molded and vulcanized at the same time. obtain.

-5th modification:
In each of the above embodiments, the separator 600 has a configuration in which three metal plates are laminated, and the portion corresponding to the power generation area DA has a flat shape, but the configuration of the separator 600 is any other configuration, It can be shaped. Specifically, a separator (for example, made of carbon) in which a groove-like reaction gas flow path is formed on the surface corresponding to the power generation area DA may be adopted, or the reaction corresponding to the portion corresponding to the power generation area You may employ | adopt the separator (For example, produced by press-molding a metal plate) which has a corrugated plate shape which functions as a gas flow path.

-6th modification:
In the above embodiment, the laminated structure 800 is composed of the MEA 810, the anode-side and cathode-side diffusion layers 820 and 830, and the anode-side and cathode-side porous bodies 840 and 850. For example, the reaction gas flow path is formed. When a separator or a separator having a corrugated plate functioning as a reaction gas flow path is used, the anode side and cathode side porous bodies 840 and 850 may be omitted.
・ Other variations:
In each of the above embodiments, the end portions of the laminated structure 800 are located on the same plane, that is, the end faces of the laminated structure 800 are formed by one plane, but this is not necessarily the case. The end surfaces of the MEA 810, the anode-side diffusion layer 820, the cathode-side diffusion layer 830, the anode-side porous body 840, and the cathode-side porous body 850 that constitute the laminated structure 800 may be located at different positions. That is, the end surface of the laminated structure 800 may be formed by a plurality of surfaces.

  As mentioned above, although the Example and modification of this invention were demonstrated, this invention is not limited to these Example and modification at all, and implementation in a various aspect is possible within the range which does not deviate from the summary. It is.

It is explanatory drawing which shows the structure of the fuel cell as one Example of this invention. 3 is a front view of a battery unit 200. FIG. It is a figure which shows the AA cross section in FIG. It is a figure which shows the shape of the cathode plate 400. FIG. FIG. 4 is a diagram showing the shape of an anode plate 300. It is a figure which shows the shape of the intermediate | middle plate. 4 is a front view of a separator 600. FIG. It is explanatory drawing which shows the flow of the oxidizing gas of a fuel cell. It is explanatory drawing which shows the flow of the fuel gas of a fuel cell. It is a figure for demonstrating manufacture of the battery unit in 1st Example. It is a figure which shows the fuel cell in a comparative example. It is a figure which shows a mode that the shift | offset | difference of the battery unit generate | occur | produced in 1st Example. It is a figure which shows the structure of the fuel cell in 2nd Example. It is a figure which shows the structure of the fuel cell in 3rd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Fuel cell 110-160 ... Manifold 200 ... Battery unit 300 ... Anode plate 400 ... Cathode plate 500 ... Intermediate plate 600 ... Separator 630 ... Fuel gas supply flow path 640 ... Fuel gas discharge flow path 650 ... Oxidation gas supply flow path 660 ... oxidizing gas discharge flow path 670 ... cooling medium flow path 700, 700b, 700c ... seal members 710, 710b, 710c ... support portions 720, 710b, 710c ... sealing ribs 730, 730b ... short-circuit suppression ribs 730b ... short-circuit suppression ribs 730c ... Short-circuit suppressing protrusion 800 ... Laminated structure 810 ... MEA
820 ... Anode side diffusion layer 820 ... Cathode side diffusion layer 830 ... Cathode side diffusion layer 840 ... Anode side porous body 840 ... Cathode side porous body 850 ... Cathode side porous body 910 ... Upper die 920 ... Lower die

Claims (7)

A fuel cell comprising a plurality of stacked battery units,
The battery unit is
A separator;
A laminated structure disposed in a first region on the separator and including an electrolyte membrane and two electrode layers;
A sealing member;
With
The sealing member is
An end seal portion bonded to a second region surrounding the first region of the separator and integrated with an end portion of the laminated structure;
A sealing rib formed on the upper surface of the end seal portion;
A convex portion formed on the upper surface of the end seal portion and disposed on at least one of the outer side and the inner side of the sealing rib;
A fuel cell. The fuel cell according to claim 1, wherein
The sealing rib is disposed so as to surround the laminated structure,
The said convex-shaped part is a fuel cell arrange | positioned on the outer side of the said rib for sealing. The fuel cell according to claim 1 or 2,
The height of the convex part in the stacking direction is a fuel cell lower than the height of the sealing rib in the stacking direction. The fuel cell according to any one of claims 1 to 3,
The fuel cell, wherein the end seal portion and the second region are bonded with a bonding force that does not cause a displacement due to a fluid pressure assumed during operation of the fuel cell. The fuel cell according to any one of claims 1 to 4, wherein
The laminated structure further includes a gas diffusion layer disposed on both surfaces of the electrolyte membrane with the electrode layer interposed therebetween. The fuel cell according to claim 5, wherein
The laminated structure further includes a porous body disposed on both surfaces of the electrolyte membrane with the electrode layer and the diffusion layer interposed therebetween. A battery unit that constitutes a fuel cell by being laminated,
A separator;
A laminated structure disposed in a first region on the separator and including an electrolyte membrane and two electrode layers;
A sealing member;
With
The sealing member is
An end seal portion in contact with a second region surrounding the first region of the separator and integrated with an end portion of the laminated structure;
A sealing rib formed on the upper surface of the end seal portion;
A convex portion formed on the upper surface of the end seal portion and disposed on at least one of the outer side and the inner side of the sealing rib;
A battery unit.

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