fuel cells

Abstract

A fuel cell is provided that can suppress the maximum amount of settling in an inter-cell seal material between fuel cell cells. [Solution] A fuel cell comprising at least a plurality of fuel cell cells and an inter-cell sealing material arranged between the plurality of fuel cell cells, wherein the plurality of fuel cell cells have ribs protruding in the direction of adjacent fuel cell cells outside the sealing range of the inter-cell sealing material, and the ribs have a height such that the compression rate of the inter-cell sealing material within the sealing range is 20% or more and 70% or less.

Description

[Technical Field]

[0001] The present disclosure relates to a fuel cell in which a plurality of fuel cells are stacked. [Background technology]

[0002] Patent Document 1 discloses a fuel cell structure in which adhesive sheets are placed between stacked fuel cell cells. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-162470 Summary of the Invention [Problem to be solved by the invention]

[0004] In fuel cells, in structures where an adhesive sheet is used to seal between fuel cell cells, the adhesive sheet is compressed by the fastening load, which causes it to sag in the thickness direction (compression set) over time, resulting in insufficient compliance when the fastening is released or the cells are displaced, and there is a risk that the seal will be destroyed due to peeling of the adhesive.

[0005] In view of the above problems, an object of the present disclosure is to provide a fuel cell that can suppress the maximum amount of settling of the inter-cell seal material between the fuel cell cells. [Means for solving the problem]

[0006] The present application discloses a fuel cell comprising at least a plurality of fuel cell cells and an inter-cell sealing material arranged between the plurality of fuel cell cells, wherein the plurality of fuel cell cells have ribs protruding in the direction of adjacent fuel cell cells outside the sealing range of the inter-cell sealing material, and the ribs have a height such that the compression rate of the inter-cell sealing material within the sealing range is 20% or more and 70% or less.

[0007] The ribs may be provided on the separators of the fuel cell.

[0008] The sealed area may be formed by a protrusion provided on the separator.

[0009] The present application discloses a fuel cell comprising at least a plurality of fuel cell cells and an inter-cell sealant arranged between the plurality of fuel cell cells, wherein the plurality of fuel cell cells have two or more ribs inside the sealing range of the inter-cell seal.

[0010] The ribs may be configured to have a height that allows the compressibility of the inter-cell sealing material to be 20% or more and 70% or less in the sealing range other than the ribs.

[0011] The ribs may be configured to have a height such that the ribs provide a compressibility of the inter-cell seal of 50% or more and 80% or less. [Effects of the Invention]

[0012] According to the present disclosure, the maximum amount of settling of the inter-cell seal can be suppressed. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a conceptual diagram illustrating the structure of a fuel cell stack 50. As shown in FIG. [Figure 2] FIG. 2 is an exploded perspective view of the fuel cell 10. FIG. [Figure 3] FIG. 3 is a plan view of the fuel cell 10. As shown in FIG. [Figure 4] FIG. 4 is a conceptual diagram illustrating the layer structure of the power generation section 11 of the fuel cell 10. As shown in FIG. [Figure 5] FIG. 5 is a conceptual diagram illustrating the layer structure in the outer peripheral portion 21 of the fuel cell 10 (first embodiment). [Figure 6] FIG. 6 is a conceptual diagram illustrating the layer structure in the outer peripheral portion 21 of the fuel cell 10 (second embodiment). [Figure 7]FIG. 7 is a diagram illustrating the outer periphery of the stacked structure of the fuel cell units 10 in the fuel cell stack 50 (first embodiment). [Figure 8] FIG. 8 is a diagram illustrating a modification of the first embodiment. [Figure 9] FIG. 9 is a diagram illustrating the outer periphery of the stacked structure of the fuel cell units 10 in the fuel cell stack 50 (second embodiment). [Figure 10] FIG. 10 is a diagram illustrating a modified example of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] 1. Basic structure of a fuel cell A fuel cell 50 (sometimes called a fuel cell stack) is a component made up of a plurality of fuel cell units 10 (about 50 to 400 units) stacked one on top of the other, which will be described in detail later, and collects electricity from the plurality of fuel cell units 10. An outline of the configuration is shown in FIG. 1. The fuel cell 50 includes a case 51, end plates 52, a plurality of fuel cell units 10, current collector plates 54, and a biasing member 55. In each figure, arrows indicate the directions of a three-dimensional Cartesian coordinate system. Here, the x direction is the in-plane direction of the overall flat fuel cell, with the direction from the fluid inlet to the outlet and the y direction perpendicular to the x direction. The z direction is the stacking direction of the components of the stacked fuel cell.

[0015] The case 51 is a housing that houses a plurality of stacked fuel cell units 10, current collector plates 54, and biasing members 55. In this embodiment, the case 51 is a rectangular cylinder with one open end and the other closed end, and a plate-like piece protrudes along the edge of the opening to the opposite side of the opening, forming a flange 51a.

[0016] The end plate 52 is a plate-shaped member that closes the opening of the case 51. The end plate 52 is fixed to the case 51 with bolts, nuts, etc. at the portion where it overlaps with the flange 51a of the case 51 so as to cover the case 51.

[0017] The fuel cell 10 will be described in detail later, but multiple fuel cell 10 are stacked on top of each other. At this time, the anode separator 18 of an adjacent fuel cell 10 is arranged so that the cathode separator 15 of one fuel cell 10 overlaps with the anode separator 18 of the adjacent fuel cell 10. The grooves 15b of the cathode separator 15 and the grooves 18b of the anode separator 18 overlap to form a cooling water flow path.

[0018] The current collector plate 54 is a member that collects current from the stacked fuel cell cells 10. Therefore, the current collector plate 54 is disposed at each end in the stacking direction of the stack of fuel cell cells 10, one serving as a positive electrode and the other as a negative electrode. Terminals (not shown) are connected to this current collector plate 54, and it is configured so that it can be electrically connected to the outside.

[0019] The biasing member 55 is housed inside the case 51 and applies a pressing force in the stacking direction to the stack of fuel cells 10. An example of the biasing member is a disc spring.

[0020] 2. Basic structure of fuel cell 2 to 5 show diagrams illustrating the basic structure of one embodiment of a fuel cell 10. The fuel cell 10 is a unit element for generating electricity by supplying hydrogen and oxygen (air), and a plurality of such fuel cell 10 are stacked to form a fuel cell 50. Fig. 2 is an exploded perspective view of the fuel cell 10 (Fig. 2 shows the fuel cell 10 as well as the inter-cell sealant 40, which will be described later), and Fig. 3 is a plan view of the fuel cell 10 (Fig. 3 shows the fuel cell 10 as well as the inter-cell sealant 40, which will be described later). Fig. 4 is a diagram illustrating the layer structure of the power generation section 11 of the fuel cell 10, and Figs. 5 and 6 are diagrams illustrating the layer structure of the outer peripheral section 21 of the fuel cell 10.

[0021] 2.1.Power Generation Unit The power generation section 11 is a section that contributes to power generation, for example, the section surrounded by a dotted line in FIG. 3, and is formed by laminating multiple layers, as shown in FIG. 4, which shows the layer structure of the power generation section 11 (part of the AA cross section). In the power generation section 11 of the fuel cell 10, one side of the electrolyte membrane 12 is a cathode (oxygen supply side) and the other side is an anode (hydrogen supply side). The cathode has a cathode catalyst layer 13, a cathode diffusion layer 14, and a cathode separator 15 stacked in this order from the electrolyte membrane 12 side. On the other hand, the anode has an anode catalyst layer 16, an anode diffusion layer 17, and an anode separator 18 stacked in this order from the electrolyte membrane 12 side. The stack of the electrolyte membrane 12, cathode catalyst layer 13, cathode diffusion layer 14, anode catalyst layer 16, and anode diffusion layer 17 is sometimes called a membrane electrode assembly. The thickness of the membrane electrode assembly is typically about 0.4 mm, and the thickness of the fuel cell 10 in the power generation section 11 is typically about 1.3 mm. Each layer can be constructed as known in the art, for example as follows.

[0022] 2.1a. Electrolyte membrane The electrolyte membrane 12 is a solid polymer thin film that exhibits good proton conductivity in a wet state. For example, it is made of a fluorine-based ion exchange membrane, and for example, a carbon-fluorine-based polymer, such as a perfluoroalkylsulfonic acid-based polymer (Nafion (registered trademark)), can be used. The thickness of the electrolyte membrane 12 is not particularly limited, but is 100 μm or less, preferably 50 μm or less, and more preferably 10 μm or less.

[0023] 2.1b. Cathode catalyst layer The cathode catalyst layer 13 is a layer containing a catalyst metal supported on a carrier. Examples of the catalyst metal include Pt, Pd, Rh, and alloys containing these. Examples of the carrier include carbon carriers, more specifically, carbon particles made of glassy carbon, carbon black, activated carbon, coke, natural graphite, artificial graphite, etc.

[0024] 2.1c. Anode catalyst layer Like the cathode catalyst layer 13, the anode catalyst layer 16 is a layer containing a catalyst metal supported on a carrier. Examples of the catalyst metal include Pt, Pd, Rh, and alloys containing these. Examples of the carrier include carbon carriers, more specifically, carbon particles made of glassy carbon, carbon black, activated carbon, coke, natural graphite, artificial graphite, etc.

[0025] 2.1d. Cathode diffusion layer The cathode diffusion layer 14 can be made of, for example, a conductive porous material. More specific examples include porous carbon materials (carbon paper, carbon cloth, glassy carbon, etc.) and porous metal materials (metal mesh, metal foam). The cathode diffusion layer may be provided with an MPL (microporous layer) if necessary. The MPL is a thin coating applied to the cathode catalyst layer 13 side of the cathode diffusion layer 14. The MPL has water-repellent or hydrophilic properties as needed to regulate moisture. MPLs are typically made primarily of a water-repellent resin such as polytetrafluoroethylene (PTFE) and a conductive material such as carbon black.

[0026] 2.1e. Anode diffusion layer The anode diffusion layer 17 can be made of, for example, a conductive porous material. More specific examples include porous carbon materials (carbon paper, carbon cloth, glassy carbon, etc.) and porous metal materials (metal mesh, metal foam).

[0027] 2.1f. Cathode separator The cathode separator 15 is a member that supplies a reactant gas (air in this embodiment) to the cathode diffusion layer 14, and has a plurality of grooves 15a on the surface facing the cathode diffusion layer 14, which function as reactant gas flow paths. The shape of the grooves is not particularly limited as long as it can appropriately supply the reactant gas to the cathode diffusion layer 14, and examples include a plate-like member formed into a corrugated shape, as in this embodiment. In this case, the plate thickness is typically 0.1 mm to 0.2 mm, and the height of the irregularities is typically about 0.5 mm. In the case of a wavy shape, grooves 15b are formed between adjacent grooves 15a on the opposite side of the cathode separator 15, and these function as cooling water flow paths.

[0028] As can be seen from FIG. 1, the cathode separator 15 has an air inlet hole A at a position extending outward from the power generating section 11 and at one end of the grooves 15a and 15b. in , cooling water inlet hole W in , hydrogen outlet hole H out and an air outlet hole A is provided at the other end of the groove 15a and the groove 15b. out , cooling water outlet hole W out , hydrogen inlet hole H in Here, the groove 15a is the air inlet hole A in , air outlet hole A out The groove 15b is connected to the cooling water inlet hole W in , cooling water outlet hole W out It is connected to.

[0029] The material constituting the cathode separator 15 may be any material that can be used as a separator for a fuel cell, and may be a gas-impermeable conductive material. Examples of such materials include dense carbon made by compressing carbon to make it gas-impermeable, and a press-molded metal plate.

[0030] 2.1g. Anode separator The anode separator 18 is a member that supplies a reactant gas (hydrogen) to the anode diffusion layer 17, and has a plurality of grooves 18a on the surface facing the anode diffusion layer 17, which function as reactant gas flow paths. The shape of the grooves is not particularly limited as long as they can properly supply the reactant gas to the anode diffusion layer 17, and examples include a type in which a plate-like member is formed into a corrugated shape, as in this embodiment. In this case, the plate thickness is typically 0.1 mm to 0.2 mm, and the height of the irregularities is typically about 0.4 mm. In the case of a wavy shape, in this embodiment, grooves 18b are formed between adjacent grooves 18a on the opposite side of the anode separator 18, and these function as cooling water flow paths.

[0031] As can be seen from FIG. 1, the anode separator 18 has an air inlet hole A at a position extending outward from the power generation section 11 and at one end of the grooves 18a and 18b. in , cooling water inlet hole W in , hydrogen outlet hole H out and an air outlet hole A is provided at the other end of the groove 18a and the groove 18b. out , cooling water outlet hole W out , hydrogen inlet hole H in Here, the groove 18a is provided with a hydrogen inlet hole H in , hydrogen outlet hole H out The groove 18b is connected to the cooling water inlet hole W in , cooling water outlet hole W out It is connected to.

[0032] The material constituting the anode separator 18 may be any material that can be used as a separator for a fuel cell, and may be a gas-impermeable conductive material. Examples of such materials include dense carbon made by compressing carbon to make it gas-impermeable, and a press-molded metal plate.

[0033] 2.1h. Power generation by the power generation unit As is well known, power generation is performed by the fuel cell 10 described above as follows. When hydrogen is supplied from the grooves 18a of the anode separator 18, the hydrogen passes through the anode diffusion layer 17 and is converted into protons (H + ) and electrons (e - ), the protons pass through the electrolyte membrane 12, and the electrons pass through conductive wires connected to the outside, and each reaches the cathode catalyst layer 13. Here, oxygen (air) is supplied to the cathode catalyst layer 13 from the grooves 15a in the cathode separator 15 via the cathode diffusion layer 14, and water (H2O) is generated in the cathode catalyst layer 13 by the protons, electrons, and oxygen. The generated water passes through the cathode diffusion layer 14, reaches the grooves 15a in the cathode separator 15, and is discharged. That is, in the fuel cell 10, the flow of electrons passing through the conductive wire connecting the anode catalyst layer 16 to the outside is used as an electric current.

[0034] 2.2.Outer periphery The outer peripheral portion 21 is located outside the power generation portion 11 enclosed by the dotted line in Fig. 3, and is the outer peripheral portion of the fuel cell 10. It does not contribute to power generation, but is a portion that supplies various fluids to the power generation portion, collects fluids from the power generation portion, and provides sealing. The outer peripheral portion 21 is formed by laminating multiple layers, as shown in Figs. 5 and 6, which show the layer structure (BB cross section) of the outer peripheral portion 21. Specifically, in this embodiment, the outer peripheral portion 21 has the following structure. Fig. 5 shows a first embodiment, and Fig. 6 shows a second embodiment.

[0035] In the outer peripheral portion 21, a resin sheet 23 is disposed between the cathode separator 15 and the anode separator 18, and the inside of the fuel cell 10 is sealed by the resin sheet 23. As can be seen from Figure 2, the resin sheet 23 is disposed so as to surround the membrane electrode assembly. The resin sheet 23 functions as a sealing member that seals the gap between the cathode separator 15 and the anode separator 18 at the outer periphery 21 of the fuel cell 10 . The resin sheet 23 includes a base material 24, an adhesive layer 25 disposed on one surface (the surface on the cathode separator side) of the base material 24, and an adhesive layer 26 disposed on the other surface (the surface on the anode separator side) of the base material 24. The adhesive layer 25 is adhered to the cathode separator 15, and the adhesive layer 26 is adhered to the anode separator 18, thereby sealing the inside of the power generation section 11.

[0036] The substrate 24 is made of a thermoplastic resin material that is electrically insulating and airtight and has a relatively high melting point. Examples of such materials include polyethylene naphthalate, polyphenylene ether, and polyphenylene sulfide. The thickness of the substrate 24 is not particularly limited, but is preferably 0.05 mm or more and 0.25 mm or less. The adhesive layers 25 and 26 are made of an adhesive and a pressure sensitive adhesive.

[0037] In addition, in the outer periphery 21, the cathode separator 15 and the anode separator 18 are each provided with a protrusion 30 that is a projection protruding in the z direction, and a rib 35. As will be explained later, the protrusions 30 are portions that form a sealing area by the inter-cell sealant 40 that is disposed between adjacent fuel cell cells 10 when the fuel cell cells 10 are stacked in the fuel cell 50. The ribs 35 are portions that function as stoppers that limit the degree to which the inter-cell sealant 40 is compressed. The specific shapes of the protrusions 30 and the ribs 35 will be explained later.

[0038] 3.Sealing between cells on the periphery 7 and 9 show stacking structures of a fuel cell 50, focusing on the outer periphery 21 of the fuel cell cells 10. Fig. 7 shows a first embodiment in which two adjacent fuel cell cells 10 are stacked from the same perspective as Fig. 5, and Fig. 9 shows a second embodiment in which two adjacent fuel cell cells 10 are stacked from the same perspective as Fig. 6.

[0039] In either embodiment, an inter-cell sealant 40 is disposed between adjacent fuel cell cells 10 in the outer periphery 21. Therefore, the inter-cell sealant 40 is laminated so that it contacts the tops of the protrusions 30 and the protrusions 30 press against the inter-cell sealant 40. Therefore, in this embodiment, the inter-cell sealant 40 is a frame-shaped sheet member disposed along the outer periphery 21, as shown in Figures 2 and 3 (shown by hatching in Figure 3).

[0040] The inter-cell sealing material 40 can be made of an adhesive sheet. The adhesive sheet may be made of a thermoplastic resin such as a polyester or modified olefin resin, or a thermosetting resin such as a modified epoxy resin. The thickness of the adhesive sheet is not particularly limited and may be 10 μm or more and 100 μm or less. The adhesive sheet may have a two-layer structure having a first adhesive layer and a second adhesive layer in this order, or a three-layer structure having a first adhesive layer, a rubber layer, and a second adhesive layer in this order. The first adhesive layer and the second adhesive layer may be made of the same material or different materials. The thickness of the adhesive layer is not particularly limited and may be 5 μm or more and 50 μm or less. Furthermore, the first adhesive layer and the second adhesive layer may have the same thickness or different thicknesses. Examples of materials for the rubber layer include EPDM (ethylene propylene diene rubber), fluorine-based rubber, silicon-based rubber, etc. The thickness of the rubber layer is not particularly limited, and may be 5 μm or more and 90 μm or less. Therefore, the first adhesive layer comes into contact with and sticks to the protrusions 30 on one side of the adjacent fuel cell 10, and the second adhesive layer comes into contact with and sticks to the protrusions 30 on the other side, thereby forming a seal.

[0041] 3.1.First form 5 and 7, in the first form, the protrusion 30 has a trapezoidal cross section and extends in the front / back direction of the page while maintaining this cross section. The shorter upper base side of the trapezoidal cross section is the protruding side and is in contact with the inter-cell sealant 40. Therefore, in this form, the sealing range of the inter-cell sealant 40 is the range of the size of the upper base, as shown in FIG.

[0042] The ribs 35 are protrusions that are arranged outside the protrusions 30 (towards the outer periphery of the fuel cell 10). As can be seen from Fig. 7, the ribs 35 are arranged so that they face each other in adjacent fuel cell cells 10. As a result, when a force is applied in a direction that narrows the gap between adjacent fuel cell cells 10 due to an external force or the like (i.e., when the inter-cell sealing material 40 tries to be compressed), the facing ribs 35 come into contact with each other and function as stoppers that restrict further movement. Therefore, the protruding height (size in the z direction) of the rib 35 is made larger than the protruding height of the convex portion 30 at least, and is set to a size that limits the inter-cell sealing material 40 so that it does not exceed the range of compression ratio described next.

[0043] When the thickness of the inter-cell sealant 40 at the open portion (the size in the z-direction of the portion not under load) is T1 and the thickness of the inter-cell sealant 40 in the sealing range is T2, the protruding height of the convex portion 30 is adjusted so that the compression rate, T2 / T1 expressed as a percentage, is 20% or more and 70% or less. Therefore, the protruding height of the rib 35 is set to a size that can regulate the compression rate so that it does not exceed 70%.

[0044] Furthermore, the distance between the sealing area indicated by L in FIG. 7 and the rib 35 (the distance between the sealing area closest to the rib 35 and the convex portion 30 side of the highest part of the rib 35) is not particularly limited, but is preferably 2 mm or more and 10 mm or less.

[0045] In this configuration, adjacent fuel cell cells 10 cannot come closer than the distance at which their ribs 35 come into contact, and the inter-cell sealing material 40 is not compressed any further. Therefore, the inter-cell sealing material 40 is not subjected to unintended and unnecessary compression force, thereby suppressing the maximum amount of settling of the inter-cell sealing material 40. Furthermore, the ribs 35 can also suppress deformation of the separator due to gas pressure inside the fuel cell 10 or expansion of the components.

[0046] Here, the upper base side of the convex portion 30 is flat, but this is not limitative, and the upper base side may be arc-shaped or may have a protrusion.

[0047] Modifications of the first embodiment are listed in Fig. 8. For simplicity, Fig. 8 shows only inter-cell sealant 40 and two separators 15 and 18 in contact therewith. 8(a) shows a configuration in which the ribs 35 are disposed on one of the two separators, 15 and 18 (only separator 18 in the illustrated example). In addition to this configuration, the height (size in the z direction) and width (size in the y direction) of the ribs 35 of separator 15 and separator 18 may be different. FIG. 8(b) shows an example in which ribs 35 are arranged on both sides of the inter-cell sealing material 40.

[0048] 3.2.Second form 6 and 9, in the second form, the protrusion 30 has a trapezoidal cross section, and two ribs 35 provided on both ends of the upper base protrude from the upper base, extending in the direction toward / away from the page while maintaining this cross section. The shorter upper base side, which is a trapezoidal cross section, is the protruding side, and the upper base and ribs 35 come into contact with and press against the inter-cell sealant 40. Therefore, in this form, the sealing range of the inter-cell sealant 40 is the range of the size of the upper base, including the ribs 35, as shown in FIG.

[0049] As in the first embodiment, the protrusions 30 form the sealing range, and the ribs 35 function as stoppers that restrict compression of the inter-cell sealant 40 in the portions of the protrusions 30 other than the ribs 35. However, in this embodiment, the inter-cell sealant 40 exists between two ribs 35 facing each other in the z direction, so the restriction is not due to direct contact between the ribs 35. Specifically, consider the following.

[0050] When the thickness of the open portion of inter-cell sealant 40 (the size in the z-direction of the portion not subjected to load) is T1 and the thickness of the portion of inter-cell sealant 40 other than ribs 35 in the sealing range is T2, the protruding height of convex portion 30 is adjusted so that the compression ratio, T2 / T1, expressed as a percentage, is 20% or more and 70% or less. When the thickness of the portion of inter-cell sealant 40 between ribs 35 is T3, the protruding height of ribs 35 is set to a size that can restrict the compression ratio, T2 / T1, expressed as a percentage to not exceed 70%, within the range of 50% or more and 80% or less.

[0051] According to this configuration, the intercell sealing material 40 is significantly compressed between the opposing ribs 35, and the spacing between the protrusions 30 does not become smaller in other areas, so the intercell sealing material 40 is not further compressed, and is therefore not subjected to unintended or unnecessary compressive force, thereby suppressing the maximum amount of settling of the intercell sealing material 40. The intercell sealing material 40 is significantly compressed between the ribs 35, but even if settling occurs in these areas of the intercell sealing material 40, the settling is suppressed by the other protrusions 30, so sealing performance is maintained.

[0052] Here, the upper base side of the convex portion 30 is flat, but this is not limitative, and the upper base side may be arc-shaped or may have a protrusion.

[0053] Modifications of the second embodiment are listed in Fig. 10. For simplicity, Fig. 10 shows only inter-cell sealant 40 and two separators 15 and 18 in contact with it. Fig. 10(a) shows an example in which one rib 35 is arranged on one convex portion 30. The position of one rib 35 is not particularly limited, and may be the center of the convex portion 30 in the y direction as shown in Fig. 10(a), or may be an end portion of the concave portion 30 (not shown), or may be another position. FIG. 10(b) shows a configuration in which ribs 35 are arranged on one of the two separators, 15 and 18 (only separator 15 in the illustrated example). In addition to this configuration, the height (size in the z direction) and width (size in the y direction) of the ribs 35 on separator 15 and the ribs 35 on separator 18 may be different. Also, the separators on one side and the other side of the inter-cell sealant 40 may be formed so as to have different shapes. For example, the ribs 35 of FIG. 9 may be applied to one separator, and the ribs 35 of FIG. 10(a) may be applied to the other separator. [Explanation of symbols]

[0054] 10... fuel cell, 11... power generation section, 15... cathode separator, 18... anode separator, 21... outer periphery, 23... resin sheet, 30... protrusion, 35... rib, 40... inter-cell seal material, 50... fuel cell

Claims

1. A fuel cell including at least a plurality of fuel cell units and an inter-cell sealant disposed between the plurality of fuel cell units, the plurality of fuel cell units have ribs protruding toward adjacent fuel cell units outside the sealing range of the inter-cell sealant, the rib has a height such that the compressibility of the inter-cell sealing material in the sealing area is 20% or more and 70% or less. fuel cell.

2. 2. The fuel cell according to claim 1, wherein the ribs are provided on a separator of the fuel cell.

3. 3. The fuel cell according to claim 2, wherein the sealed area is formed by a protrusion provided on the separator.

4. A fuel cell including at least a plurality of fuel cell units and an inter-cell sealant disposed between the plurality of fuel cell units, the plurality of fuel cells have two or more ribs inside the sealing range of the inter-cell sealant; fuel cell.

5. 5. The fuel cell according to claim 4, wherein the ribs have a height such that the compressibility of the inter-cell sealant is 20% or more and 70% or less in the sealing range other than the ribs.

6. 6. The fuel cell according to claim 4, wherein the ribs have a height such that the compressibility of the inter-cell seal material is 50% or more and 80% or less.

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