JP2008004427A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve durability of a fuel cell by preventing damage of a ceramics adhesive, in a fuel cell using a ceramics adhesive. <P>SOLUTION: This fuel cell is provided with: an electrolyte layer; a stacked member stacked along with the electrolyte layer, and having a load reception part receiving at least a part of pressure applied in the stacking direction to a surface of the stacked member; an adjacent member arranged on the stacked member, and applying pressure in the stacking direction to the surface of the stacked member; and a seal part formed by a ceramics adhesive, arranged on the surface of the stacked member, and attaching the stacked member to the adjacent member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cell.

  In a fuel cell in which a member such as a gas separator that forms a reaction gas flow path between the electrolyte layer and the electrolyte layer is laminated, it is formed inside the fuel cell by adhering adjacent members without gaps. The sealing property is ensured in the flow path of the reaction gas or refrigerant. An organic adhesive such as a resin is known as an adhesive capable of realizing a sealing property. Organic adhesives are useful in fuel cells that have a temperature range of about 100 ° C. or lower, that is, a so-called low temperature range. However, it is difficult to use such an organic adhesive in a fuel cell that generates power in a temperature range called a so-called intermediate temperature range of 300 ° C. to 600 ° C., for example. Therefore, conventionally, a ceramic adhesive having better heat resistance has been used in fuel cells that operate in an intermediate temperature range (see, for example, Patent Document 1).

JP-A-7-37596 Japanese Patent Laid-Open No. 11-154525 JP-A-10-92450 Japanese Patent Laid-Open No. 10-32244

  A ceramic adhesive is an adhesive excellent in heat resistance and insulation, but has a property of being vulnerable to impact. Therefore, when a ceramic adhesive is placed between laminated members such as gas separators and used for bonding between these laminated members, a ceramic load is applied by applying a fastening load acting on the ceramic adhesive inside the fuel cell. The agent may be damaged, and the sealing performance inside the fuel cell and the durability of the fuel cell may be impaired.

  The present invention has been made to solve the above-described conventional problems, and aims to improve the durability of a fuel cell by suppressing damage to the ceramic adhesive in a fuel cell using a ceramic adhesive. To do.

In order to achieve the above object, the first fuel cell of the present invention comprises:
An electrolyte layer;
A laminated member laminated together with the electrolyte layer, the laminated member comprising a load receiving portion that receives at least part of the pressure applied to the surface of the laminated member in the direction of the lamination;
An adjacent member that is disposed on the laminated member and applies pressure in the direction of the lamination to the surface of the laminated member;
A gist of the present invention is that it is formed of a ceramic adhesive and is disposed on the surface of the laminated member, and includes a seal portion that adheres the laminated member and the adjacent member.

  According to the first fuel cell of the present invention configured as described above, the load receiving portion receives at least a part of the pressure applied to the surface of the stacked member in the stacking direction, and the pressure applied to the seal portion is reduced. Therefore, damage to the seal portion made of the ceramic adhesive can be suppressed. Thereby, the reliability and durability of the fuel cell can be improved.

In such a first fuel cell of the present invention,
The weight receiving portion is a portion where the laminated member contacts the adjacent member,
The seal portion may bond between the laminated member and the adjacent member in the vicinity of the load receiving portion.

  With such a configuration, at least part of the pressure applied to the surface of the laminated member in the direction of lamination is applied to the contact portion of the laminated member with the adjacent member, and the laminated member and the adjacent member are bonded in the vicinity thereof. It is possible to suppress the pressure applied to the sealing portion.

In the first fuel cell of the present invention,
The laminated member has a recess filled with the ceramic adhesive on the surface thereof,
The adjacent member may be in contact with the laminated member in a region covering the recess.

  With this configuration, since at least part of the pressure applied to the surface of the laminated member in the direction of lamination is applied to the portion where the laminated member is in contact with the adjacent member around the concave portion, the ceramic filled in the concave portion The pressure applied to the seal portion made of the adhesive can be suppressed.

Alternatively, in the first fuel cell of the present invention,
The laminated member has a concave portion into which the adjacent member is fitted to form the load receiving portion,
The seal portion may be disposed between the recess surface and the adjacent member inside the recess.

  With such a configuration, since the adjacent member is fitted into the recess provided with the seal portion, a wide contact area between the seal portion and the adjacent member is ensured, and adhesion between the laminated member and the adjacent member is ensured. Strength can be increased. Moreover, when the adjacent member is fitted into the recess, the positioning of the adjacent member can be facilitated when assembling the fuel cell, and the displacement of the adjacent member inside the fuel cell can be suppressed.

In the first fuel cell of the present invention,
The adjacent member may be a member disposed between the laminated member and another laminated member laminated adjacent to the laminated member.

  With such a configuration, when the adjacent member is disposed between the adjacent laminated members and the laminated member and the adjacent member are bonded by the seal portion, damage to the seal portion can be suppressed.

  In the first fuel cell of the present invention, the adjacent member may be a high elastic modulus member having a higher compression elastic modulus than the laminated member.

  With such a configuration, the adjacent member absorbs part of the pressure in the stacking direction inside the fuel cell, whereby the pressure applied in the stacking direction with respect to the surface of the stacking member can be further reduced. .

  Alternatively, in the first fuel cell of the present invention, the adjacent member may be an insulating member having an insulating property.

  With such a configuration, insulation can be ensured by providing a seal portion between the laminated member and the adjacent member.

  In the first fuel cell of the present invention, the adjacent member may be constituted by a mica plate.

  With such a configuration, it is possible to easily ensure a higher compressive elastic modulus and insulation than the laminated member in the adjacent member.

In the first fuel cell of the present invention,
The laminated member may be a frame member that is integrated with the electrolyte layer and supports the electrolyte layer.

  With such a configuration, when the sealing of the gas flow path formed on the electrolyte layer integrated with the frame member is secured by adhering the frame member and the adjacent member by the seal portion, the seal is provided. Damage to the part can be suppressed.

Alternatively, in the first fuel cell of the present invention,
The laminated member may be a separator that forms part of a wall surface of a flow path for gas and / or refrigerant that is subjected to an electrochemical reaction.

  With such a configuration, when the separator and the adjacent member are bonded to each other by the seal portion, the seal portion is not damaged when the sealing property of the gas and / or refrigerant flow path formed on the separator is secured. Can be suppressed.

The second fuel cell of the present invention comprises:
An electrolyte layer;
A plurality of laminated members laminated together with the electrolyte layer, the load receiving portion receiving at least a part of the pressure applied in the direction of the lamination from the laminated member adjacent to the laminated member with respect to the surface of the laminated member A laminated member comprising:
The gist of the present invention is that the sealing member is formed of a ceramic adhesive and is disposed on the surface of the laminated member, and includes a seal portion that bonds the laminated member and the laminated member adjacent to the laminated member.

  According to the second fuel cell of the present invention configured as described above, the load receiving portion receives at least a part of the pressure applied to the surface of the stacked member in the stacking direction, and the pressure applied to the seal portion is reduced. Therefore, damage to the seal portion made of the ceramic adhesive can be suppressed. Thereby, the reliability and durability of the fuel cell can be improved.

In the second fuel cell of the present invention,
The weight receiving portion is a portion where the laminated member contacts a laminated member adjacent to the laminated member,
The seal portion may bond between the laminated member and a laminated member adjacent to the laminated member in the vicinity of the load receiving portion.

  With such a configuration, at least part of the pressure applied to the surface of the laminated member in the direction of lamination is applied to the contact portion of the laminated member with the adjacent laminated member. The pressure applied to the seal portion can be suppressed.

In the second fuel cell of the present invention,
The laminated member has a recess filled with the ceramic adhesive on the surface thereof,
The laminated member adjacent to the laminated member may be in contact with the laminated member in a region covering the recess.

  With such a configuration, at least part of the pressure applied to the surface of the laminated member in the direction of lamination is applied to a portion of the periphery of the recessed portion that is in contact with the adjacent laminated member, so that the recessed portion is filled. The pressure applied to the seal portion made of the ceramic adhesive thus made can be suppressed.

  In the first or second fuel cell of the present invention, the fuel cell may have an operating temperature of 300 to 600 ° C. during power generation.

  With such a configuration, in a fuel cell that generates power in a temperature range where an organic adhesive cannot be used, when the seal portion is formed using a ceramic adhesive having excellent heat resistance, the durability of the fuel cell Can be improved.

In such a first or second fuel cell of the present invention, further,
A hydrogen permeable metal layer formed by a hydrogen permeable metal and acting as an anode;
The electrolyte layer may be made of a solid oxide having a proton conductor and formed on the hydrogen permeable metal layer.

  With such a configuration, in the fuel cell that enables power generation at 300 to 600 ° C. by forming an electrolyte layer made of a solid oxide on the hydrogen permeable metal layer, a seal portion is formed using a ceramic adhesive. When forming the fuel cell, the durability of the fuel cell can be improved.

  The present invention can be realized in various forms other than those described above. For example, the present invention can be realized in the form of a method for ensuring sealing performance in a fuel cell.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Fuel cell configuration:
B. Gasket and seal configuration:
C. Second embodiment:
D. Third embodiment:
E. Variation:

A. Fuel cell configuration:
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a fuel cell 10 according to a first embodiment of the present invention. The fuel cell 10 according to the present embodiment includes a plurality of single cells 20 and has a stack structure in which the single cells 20 are stacked with a separator 30 interposed between the single cells 20. The single cell 20 includes a MEA (Membrane Electrode Assembly) 40 and a cathode current collector 26 and an anode current collector 28 formed on each surface of the MEA 40.

  FIG. 2 is an explanatory diagram showing the A region in FIG. 1 in an enlarged manner. The MEA 40 includes a hydrogen permeable metal layer 22, an electrolyte layer 21 formed on one surface of the hydrogen permeable metal layer 22, and a cathode electrode 24 formed on the electrolyte layer 21. The cathode current collector 26 is disposed on the surface of the MEA 40 on the cathode electrode 24 side, and the anode current collector 28 is disposed on the surface of the MEA 40 on the hydrogen permeable metal layer 22 side.

  The hydrogen permeable metal layer 22 is a substantially rectangular metal film formed of a metal having hydrogen permeability. Such a hydrogen permeable metal layer 22 can be formed of, for example, palladium (Pd) or a Pd alloy. Alternatively, a group 5 metal such as vanadium (V) (in addition to V, niobium, tantalum, etc.) or an alloy of group 5 metal is used as a base material, and Pd or Pd alloy is formed on at least one surface (the anode current collector 28 side). A multilayer film in which layers are formed can be obtained. In the hydrogen permeable metal layer 22, Pd constituting at least the surface on the anode current collector 28 side has an activity of dissociating hydrogen molecules when hydrogen passes through the hydrogen permeable metal layer 22. In the present embodiment, the hydrogen permeable metal layer 22 functions as an anode electrode.

The electrolyte layer 21 is a layer made of a solid oxide having proton conductivity, and is formed so as to cover one surface of the hydrogen permeable metal layer 22. As the solid oxide constituting the electrolyte layer 21, for example, BaCeO ₃ or SrCeO ₃ based ceramic proton conductors can be used. Since the electrolyte layer 21 is formed on the dense hydrogen permeable metal layer 22, it is possible to sufficiently reduce the thickness. Therefore, the membrane resistance of the solid oxide can be reduced, and the fuel cell can be operated at about 300 to 600 ° C., which is lower than the operating temperature of the conventional solid oxide fuel cell.

  The cathode electrode 24 is a metal layer formed of a noble metal having catalytic activity that promotes an electrochemical reaction, and is formed so as to cover the electrolyte layer 21. In this embodiment, the cathode electrode 24 is made of Pd. In the case where the cathode electrode 24 is composed of another kind of noble metal having no hydrogen permeability, such as platinum (Pt), the cathode electrode 24 is formed on the outer side (cathode current collector 26) by forming the cathode electrode 24 sufficiently thin. Side) and the electrolyte layer 21 may be ensured.

  The cathode current collector 26 and the anode current collector 28 are formed of a metal porous body such as foam metal or metal mesh, and are disposed so as to cover the cathode electrode 24 or the hydrogen permeable metal layer 22, respectively. Yes. Specifically, a porous body made of titanium or stainless steel can be used. In the cathode current collector 26 and the anode current collector 28, a space formed by a large number of pores formed inside functions as a gas flow path in a single cell through which a gas subjected to an electrochemical reaction passes. Specifically, the space formed by the pores inside the cathode current collector 26 disposed between the cathode electrode 24 and the separator 30 is an oxidizing gas in a single cell through which an oxidizing gas containing oxygen passes. Functions as a flow path. The space formed by the pores inside the anode current collector 28 disposed between the hydrogen permeable metal layer 22 and the separator 30 is a fuel gas in a single cell through which hydrogen-containing fuel gas passes. Functions as a flow path. The cathode current collector 26 and the anode current collector 28 function as a current collector that electrically connects the electrode and the separator 30 in addition to forming the gas flow path in the single cell as described above.

  The fuel cell 10 according to the present embodiment further includes a frame 45. The frame 45 is a member for supporting the MEA 40 and can be formed of a metal such as stainless steel or titanium. FIG. 3 is a plan view illustrating a schematic configuration of the frame 45. FIG. 3A shows the state of the surface on the side where the anode current collector 28 is disposed, and FIG. 3B shows the state of the surface on the side where the cathode current collector 26 is disposed. As shown in FIG. 3, the frame 45 has a hole 42 into which the MEA 40 is fitted at the center, and further includes holes 50 to 55 in the vicinity of the outer periphery. Further, on both surfaces of the frame 45, grooves 56 and 57 which are concave portions formed in a linear shape are formed so as to surround the hole portions 50 to 55 and the hole portion 42. Here, the groove 57 formed on the surface on the anode current collector 28 side is not formed in the vicinity of the side on the hole 42 side in the holes 50 and 55 (see FIG. 3A). Further, the groove 56 formed on the surface on the cathode current collector 26 side is not formed in the vicinity of the side on the hole 42 side in the holes 52 and 53 (see FIG. 3B). Such linear grooves 56 and 57 can be formed by machining, press molding, or etching, for example. The grooves 56 and 57 have a structure related to a gas seal in the fuel cell 10 and will be described in detail later. When assembling the fuel cell 10, for example, the hydrogen permeable metal layer 22 is fitted into the hole in the center of the frame 45, and the two are integrated by laser beam welding or the like. The electrolyte layer 21 and the cathode electrode 24 may be formed sequentially. In FIG. 3, the position corresponding to the cross section of FIG. 1 is shown as a 1-1 cross section.

The holes 50 to 55 provided in the frame 45 form a fluid manifold that penetrates the inside of the fuel cell 10 in the stacking direction when the fuel cell 10 is assembled by laminating the frame 45 together with the separator 30. Specifically, the hole 50 forms a fuel gas supply manifold for distributing the fuel gas supplied from the outside to the fuel gas flow paths in each single cell (indicated as H ₂ in in FIG. 3), The hole 55 forms a fuel gas discharge manifold that guides the fuel gas discharged from each single-cell fuel gas flow path to the outside (indicated as H ₂ out in FIG. 3). The hole 52 forms an oxidizing gas supply manifold for distributing the oxidizing gas supplied from the outside to the oxidizing gas flow paths in each single cell (indicated as O ₂ in in FIG. 3). 53 forms an oxidizing gas discharge manifold that guides the oxidizing gas discharged from the oxidizing gas flow paths in each single cell to the outside (indicated as O ₂ out in FIG. 3). Further, the hole 51 forms a refrigerant supply manifold for distributing a refrigerant (for example, water or air) supplied from the outside to each inter-cell refrigerant flow path to be described later (in FIG. 3, the refrigerant in The hole portion 54 forms a refrigerant discharge manifold that guides the refrigerant discharged from the inter-unit cell refrigerant flow paths to the outside (in FIG. 3, the refrigerant). indicated as out).

  The separator 30 is a gas-impermeable plate-like member formed of a metal material such as stainless steel, titanium, or aluminum, and has substantially the same outer peripheral shape as the frame 45. The separator 30 has a three-layer structure in which three metal plates 31 to 33 are overlapped. FIG. 4 is a plan view illustrating the configuration of the three metal plates 31 to 33 that constitute the separator 30. 4A shows the metal plate 31 arranged on the anode current collector 28 side, FIG. 4B shows the metal plate 32 arranged in the center, and FIG. 4C shows the cathode current collector. The metal plate 33 arrange | positioned at the electric conductor 26 side is represented.

  As shown in FIG. 4, the metal plates 31 and 33 are provided with similar holes 50 to 55 at positions overlapping the holes 50 to 55 of the frame 45. On the other hand, the metal plate 32 includes holes 50, 52, 53, and 55, but includes refrigerant holes 34 that are a plurality of elongated through holes instead of the holes 51 and 54. The coolant hole 34 is a structure for forming a single-cell coolant channel that is a coolant channel for cooling the fuel cell in the separator 30. Each refrigerant hole 34 is formed such that the vicinity of both end portions thereof overlaps with the hole portions 51 and 54. Therefore, in the fuel cell 10, the refrigerant flowing through the refrigerant supply manifold formed by the hole 51 is distributed to the inter-cell refrigerant flow path formed by the refrigerant holes 34 in each separator 30, and then the holes The part 54 gathers into the refrigerant discharge manifold formed. In addition, although both surfaces are formed as smooth surfaces, the metal plates 31 and 33 surround the holes 50 to 55 on one surface, and grooves 35 and 36 that are linear recesses are formed. . Specifically, a groove 35 is formed on the surface of the metal plate 31 on the anode current collector 28 side, and the surface of the metal plate 33 on the cathode current collector 26 side (the back surface shown in FIG. 4C). ) Is formed with a groove 36. The groove 35 formed in the metal plate 31 is provided at a position where it overlaps with the groove 57 formed on one surface of the frame 45 when the separator 30 is overlapped with the frame 45. Further, the groove 36 formed in the metal plate 33 is provided at a position where it overlaps with the groove 56 formed on the other surface of the frame 45 when the separator 30 is overlapped with the frame 45. Such linear grooves 35 and 36 can be formed by, for example, machining, press molding, or etching. The grooves 35 and 36 have a structure related to a gas seal in the fuel cell 10 and will be described in detail later.

  Further, the fuel cell 10 includes gaskets 60 and 62 between the metal plate 31 and the frame 45 in the separator 30 and between the metal plate 333 and the frame 45 in the separator 30 (see FIG. 1). ). The gaskets 60 and 62 have a structure related to a gas seal in the fuel cell 10 and will be described in detail later.

B. Gasket and seal configuration:
FIG. 5 is an explanatory diagram showing the B region in FIG. 1 in an enlarged manner. The fuel cell 10 includes a seal portion 64 formed of a ceramic adhesive inside grooves 56, 57, 35, and 36 formed on the surfaces of the frame 45 and the separator 30. Gaskets 60 and 62 provided between the separator 30 and the frame 45 are arranged so as to cover the seal portion 64 formed inside the grooves 56, 57, 35, and 36. That is, in the fuel cell 10, the sealing performance in each manifold and the gas flow path in the single cell is secured by adhering the gaskets 60 and 62 to the separator 30 or the frame 45 by the seal portion 64.

  Examples of the ceramic adhesive constituting the seal portion 64 include alumina-based, zirconia-based, and silica-based adhesives. The seal portion 64 is formed by filling the ceramic adhesive in grooves 56, 57, 35, and 36 (see FIGS. 3 and 4) formed on the surfaces of the frame 45 and the separator 30.

  The gaskets 60 and 62 are formed of a mica plate (a plate-like member obtained by pressure-molding a mica plate or a laminated mica bonded together with an adhesive and heating them) as an insulating member. The gaskets 60 and 62 have the same planar shape as the grooves 56, 57, 35 and 36 in which the seal portion 64 is formed, and have a width wider than the grooves 56, 57, 35 and 36. , 35, 36 are arranged to cover. A gasket 60 is disposed on the seal portion 64 formed by filling the groove 35 formed in the metal plate 31 of FIG. 4A with a ceramic adhesive, and the anode current collector 28 is disposed on the metal plate 31. FIG. 6A shows the state of the plane, that is, the state of the plane at the position of the arrow C in FIG. In FIG. 6A, the state in which the fuel gas flowing through the fuel gas supply manifold flows to the fuel gas discharge manifold via the fuel gas flow path in the single cell is indicated by arrows.

  Further, a gasket 62 is disposed on a seal portion 64 formed by filling a groove 56 formed in the frame 45 of FIG. 3B with a ceramic adhesive, and a cathode collector is disposed on the MEA 40 integrated with the frame 45. FIG. 6B shows the state in which the electric body 26 is arranged, that is, the state of the plane at the position of the arrow D in FIG. In FIG. 6B, the state in which the oxidizing gas flowing through the oxidizing gas supply manifold flows to the oxidizing gas discharge manifold via the oxidizing gas flow path in the single cell is indicated by arrows. The gaskets 60 and 62 having the shape shown in FIG. 6 can be manufactured by punching a thin mica plate with, for example, a press.

  As shown in FIGS. 5 and 6, the gaskets 60 and 62 are formed in a shape that covers the grooves 56, 57, 35, and 36 in which the seal portion 64 is disposed. In the peripheral region of 57, 35, 36, the separator 30 or the frame 45 is in direct contact. In the separator 30 or the frame 45, an area where the gaskets 60 and 62 are in direct contact is shown as an E area in FIG. By providing the gaskets 60 and 62 having the above-described shape, members including the separator 30 and the frame 45 are stacked and applied to the surface of the separator 30 or the frame 45 inside the fuel cell 10 assembled by applying fastening pressure in the stacking direction. Part of the fastening pressure is applied to the E region where the gaskets 60 and 62 are in direct contact. As a result, the fastening pressure applied to the seal portion 64 formed by the ceramic adhesive filled in the grooves 56, 57, 35, and 36 is reduced. That is, the E region receives a part of the fastening pressure applied to the surface of the separator 30 or the frame 45 and functions as a load receiving portion that suppresses the fastening pressure applied to the seal portion 64.

  According to the fuel cell 10 of the present embodiment configured as described above, a part of the fastening pressure is applied to the E region around the grooves 56, 57, 35, and 36 provided with the seal portion 64, and the seal. Since the fastening pressure applied to the portion 64 is reduced, damage to the seal portion made of the ceramic adhesive can be suppressed. Thereby, the reliability and durability of the fuel cell 10 can be improved.

  Here, the mica plate constituting the gaskets 60 and 62 is a member softer than the metallic separator 30, specifically, a member having a small value of compression elastic modulus (Young's modulus). For example, the Young's modulus of iron is about 210000 MPa, the Young's modulus of aluminum is about 70000 MPa, and the Young's modulus of mica plate is about 3000 MPa. By placing the soft member between the separator 30 and the frame 45 which are laminated members laminated together with the electrolyte layer, a part of the fastening pressure is absorbed by the gaskets 60 and 62 and the fastening applied to the seal portion 64 is performed. The pressure can be suppressed.

  The mica plate constituting the gasket 62 is an insulating member. Therefore, by arranging the gasket 62 between the metal plate 33 and the frame 45 of the separator 30, the sealing property in the oxidizing gas flow path in the single cell is ensured, and at the same time, a short circuit between the metal plate 33 and the frame 45 is achieved. It can be easily suppressed.

  When the amount of the ceramic adhesive filled in the grooves 56, 57, 35, 36 is large, when the gaskets 60, 62 are arranged and fastening pressure is applied, the surface of the E region and the gaskets 60, 62 are applied. There is a possibility that a ceramic adhesive layer is formed between the two. When such a ceramic adhesive layer is formed, the fastening pressure is applied to the ceramic adhesive layer without being relaxed in the E region which is the load receiving portion. In order to ensure the sealing performance by the seal portion 64, it is necessary to fill the grooves 56, 57, 35, and 36 with a sufficient amount of the ceramic adhesive, but the ceramic adhesive layer as described above is not formed. When the ceramic adhesive is filled in the grooves 56, 57, 35, and 36, it is desirable to appropriately adjust the amount of adhesive used.

C. Second embodiment:
FIG. 7 is a schematic cross-sectional view showing a structure for sealing in the fuel cell of the second embodiment. Since the fuel cell of the second embodiment has the same configuration as that of the fuel cell of the first embodiment except for the structure for sealing shown in FIG. 7, the same reference numerals are used for parts common to the first embodiment. A detailed description will be omitted. FIG. 7 is a diagram showing a part corresponding to the part shown in FIG. 5 in the first embodiment.

  In the separator 30 included in the fuel cell of the second embodiment, grooves 35 and 36 and grooves 56 and 57 having the same shape as the first embodiment are formed on the surfaces of the metal plates 31 and 33 and the frame 45. Further, in the fuel cell of the second embodiment, the gaskets 160, 160 are replaced between the metal plate 31 and the frame 45, and between the metal plate 33 and the frame 45, instead of the gaskets 60, 62 of the first embodiment. 162 is arranged. Unlike the gaskets 60 and 62 of the first embodiment, the gaskets 160 and 162 have a narrower width than the grooves 35, 36, 56 and 57 and are fitted into the grooves 35 and 36. Further, a seal portion 164 formed by a ceramic adhesive filled in a space between the fitted gaskets 160 and 162 is provided inside the grooves 35, 36, 56 and 57.

  According to the fuel cell of the second embodiment configured as described above, the fastening pressure is applied to the surface of the separator 30 via the gaskets 160 and 162 fitted in the grooves 35, 36, 56 and 57. . Therefore, contact portions with the gaskets 160 and 162 in the grooves 35, 36, 56, and 57 mainly receive fastening pressure. And the sealing part 164 which consists of a ceramic adhesive with which the groove | channels 35, 36, 56, and 57 were filled has the sealing performance in the gas flow path in a single cell, and a manifold. In the second embodiment, at least a part of the fastening pressure is received and the portion acting as a load receiving portion that suppresses the pressure applied to the seal portion 164, that is, the contact with the gaskets 160, 162 in the grooves 35, 36, 56, 57. The region is shown as an F region in FIG. Thus, the contact part with the gaskets 160, 162 in the grooves 35, 36, 56, 57 acts as a load receiving portion, so that the fastening pressure applied to the seal portion 164 is suppressed, and the ceramics as in the first embodiment. An effect of suppressing damage to the seal portion made of the adhesive can be obtained. Since the mica plate constituting the gaskets 160 and 162 is a member having fine irregularities on the surface, strictly in the F region, flat surfaces are not in contact with each other, and the ends of the gaskets 160 and 162 are not in contact with each other. The fine convex part in the part and the surfaces of the grooves 35, 36, 56, 57 contact.

  Furthermore, according to the fuel cell of the second embodiment, the gasket 160, 162 is a member softer than the separator 30, specifically, a member having a smaller value of compression elastic modulus (Young's modulus). The same effect as the example can be obtained. Further, the same effect as in the first embodiment can be obtained because the mica plate constituting the gasket 62 is an insulating member.

  Further, according to the fuel cell of the second embodiment, since the gaskets 160 and 162 are fitted into the grooves 35, 36, 56 and 57, the gaskets 160 and 162 can be easily positioned when the fuel cell is assembled. . Further, it is possible to prevent displacement of the gaskets 160 and 162 during assembly or after assembly.

  Furthermore, according to the fuel cell of the second embodiment, since the gasket is fitted in the groove filled with the ceramic adhesive, the contact area between the seal portion and the gasket can be increased. At that time, the mica plate constituting the gasket has fine irregularities on the surface, thereby further increasing the effect of widening the contact area between the seal portion and the gasket. As described above, since the contact area between the seal portion and the gasket is increased, the adhesive strength between the separator 30 or the frame 45 and the gasket is increased, so that the sealing performance and vibration resistance in the fuel cell can be improved.

  When the fuel cell of the second embodiment is assembled, the gaskets 160 and 162 are fitted after the ceramic adhesive is filled in the grooves 35, 36, 56 and 57, and the respective laminated members are sequentially laminated. At that time, it is desirable that the formation of the ceramic adhesive layer is suppressed at a portion where the end portions of the gaskets 160 and 162 abut against the bottom surfaces of the inner walls of the grooves 35, 36, 56 and 57. Therefore, when the ceramic adhesive is filled, for example, the ceramic adhesive may be applied around the side surfaces of the inner walls of the grooves 35, 36, 56, and 57. When the gaskets 160 and 162 are fitted into the grooves 35, 36, 56, and 57 filled with the ceramic adhesive, the filled ceramic adhesive protrudes from the grooves 35, 36, 56, and 57 and rises. There is no problem. Even when the filled ceramic adhesive protrudes from the grooves 35, 36, 56, and 57 and rises, if the insulating ceramic adhesive is used, the metal plate 33 and the frame 45 are not short-circuited.

D. Third embodiment:
FIG. 8 is a schematic sectional view showing a structure for sealing in the fuel cell of the third embodiment. Since the fuel cell of the third embodiment has the same configuration as that of the fuel cell of the first embodiment except for the seal structure shown in FIG. 8, the same reference numerals are used for parts common to the first embodiment. A detailed description will be omitted. FIG. 8A is a view showing a portion corresponding to the portion shown in FIG. 5 in the first embodiment, and FIG. 8B is an enlarged view of the main part of the surface of the metal plate 33 provided in the separator 30. FIG.

  In the separator 30 provided in the fuel cell of the third embodiment, grooves 235, 35 and 57, respectively, on the surfaces of the metal plates 31, 33 and the frame 45, are located at positions similar to the grooves 35, 36 and the grooves 56, 57 of the first embodiment. 236 or grooves 256 and 257 are formed. As a representative of these grooves, a cross-sectional state of the groove 236 formed in the metal plate 33 is shown in FIG. The grooves 235, 236 and the grooves 256, 257 are formed in a first recess 70 formed in one step from the surface where the metal plates 31, 33 and the frame 45 are in contact with the adjacent current collector, and in the first recess 70. And a second recess 72 formed so as to be further recessed than the first recess 70.

  Here, in the fuel cell of the third embodiment, a gasket 260 is provided between the metal plate 31 and the frame 45 and between the metal plate 33 and the frame 45 instead of the gaskets 60 and 62 of the first embodiment. , 262 are arranged. Unlike the gaskets 60 and 62 of the first embodiment, the gaskets 260 and 262 have a narrower width than the grooves 235, 236, 256, and 257, and the first recesses 70 of the grooves 235, 236, 256, and 257 are provided. It is fitted inside. In the fuel cell of the third embodiment, the ceramic adhesive is provided in the spaces between the gaskets 260 and 262 in the first recess 70 and in the second recess 72 in the grooves 235, 236, 256 and 257. A seal portion 264 formed by the above is provided.

  According to the fuel cell of the third embodiment configured as described above, the fastening pressure is applied to the surface of the separator 30 through the gaskets 260 and 262 fitted in the first recess 70. Therefore, the contact part with the gaskets 260 and 262 in the first recess 70 mainly receives the fastening pressure. And the sealing part 264 formed in the groove | channels 235, 236, 256, 257 ensures the sealing performance in the gas flow path in a single cell and a manifold. In the third embodiment, a portion that receives at least a part of the fastening pressure and serves as a load receiving portion that suppresses the pressure applied to the seal portion 264, that is, a contact portion with the gaskets 260 and 262 in the first recess 70, FIG. 8 shows the G region. In this way, the contact portion with the gaskets 260 and 262 on the surface of the first recess 70 acts as a load receiving portion, so that the fastening pressure applied to the seal portion 264 is suppressed, and the ceramic adhesive is used as in the first embodiment. The effect which suppresses the damage of the seal part which consists of is acquired.

  Further, according to the fuel cell of the third embodiment, since the gaskets 260 and 262 are fitted into the first recess 70, the gaskets 260 and 262 can be easily positioned as in the second embodiment. The effect of preventing the displacement of the gaskets 260 and 262 can be obtained. Furthermore, according to the fuel cell of the third embodiment, the gasket 160, 162 is the softer member than the separator 30, the same effect as the first embodiment, or the mica plate constituting the gasket 62 is insulative. The effect similar to 1st Example by being a member can be acquired. Further, according to the fuel cell of the third embodiment, the gaskets 260 and 262 are formed by the seal portion 264 formed in the first recess 70 and the seal portion 264 formed in the second recess 72. Since both are bonded, the bonding strength between the separator 30 or the frame 45 and the gaskets 260 and 262 can be increased.

E. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

E1. Modification 1:
In the first to third embodiments, the configuration for gas sealing between the frame 45 and the metal plate 31 and the configuration for gas sealing between the frame 45 and the metal plate 33 are the same. However, they may be configured differently. For example, since it is not necessary to ensure insulation between the frame 45 and the metal plate 31, a seal portion made of a ceramic adhesive is disposed between the frame 45 and the metal plate 31 when applying the present invention. In addition, it is possible to bond the frame 45 and the metal plate 31 only by the seal portion without providing a gasket. An example of such a configuration is shown in FIG. The fuel cell shown in FIG. 9 is the same as that of the first embodiment except for the structure relating to the seal between the frame 45 and the metal plate 31, and the same reference numerals are given to the parts common to the first embodiment. Yes. Here, on the surface where the metal plate 31 and the frame 45 are in contact with each other, the thickness around the groove forming the seal portion 64 is formed to be thicker according to the thickness of the anode current collector 28, and the frame 45 and the metal plate 31 are formed. Are in direct contact with each other. Even in such a configuration, the fastening pressure applied to the surface of the separator 30 or the frame 45 is applied to the surface portions in contact with each other in preference to the seal portion 64 formed in the groove. A similar effect of suppressing the fastening pressure can be obtained. In FIG. 9, a portion that receives at least a part of the fastening pressure and functions as a load receiving portion that suppresses the pressure applied to the seal portion 64 is shown as an H region.

  Or in the structure which concerns on the seal | sticker between the flame | frame 45 and the metal plate 31 which does not need to ensure insulation, it is good also as not applying this invention using a ceramic adhesive agent. In this case, for example, a groove is not provided on the surface where the frame 45 and the metal plate 31 face each other, and instead of an insulating gasket made of a mica plate or the like, a conductive gasket formed of metal is arranged. You may do it. If, for example, a gasket made of nickel or tungsten is used as the metal gasket, these metals are excellent in heat resistance and corrosion resistance, and have a smaller value of compression modulus than stainless steel and titanium, which are constituent metals of the separator. This is desirable because it can be a gasket. By making a gasket slightly thicker than the thickness of the anode current collector 28, placing the gasket at a predetermined position between the frame 45 having a flat surface and the metal plate 31, and crushing with a fastening load, Sealing performance can be realized.

E2. Modification 2:
In addition, the constituent members of the fuel cell may be formed of a material different from that of the first to third embodiments, or the constituent members of the fuel cell may have a shape different from that of the embodiments. For example, the separator 30, the cathode current collector 26, or the anode current collector 28 can be formed of a carbon material. Further, the separator may not be formed as a flat plate member, but may be provided with irregularities for forming a gas flow path in the single cell between the separator and the MEA 40.

E3. Modification 3:
In the first to third embodiments, the MEA 40 is supported by the frame 45 and the structure including the seal portion made of the ceramic adhesive is provided between the separator 30 and the frame 45. However, a different configuration may be used. For example, when the MEA 40 is supported by a structure different from that of the frame 45 and adjacent separators are brought into direct contact with each other, a load receiving portion similar to that of the embodiment is formed at both contact portions of the adjacent separators, and You may provide the seal part similar to an Example between the separators which fit. In a fuel cell, a plurality of laminated members that are laminated together with an electrolyte layer, and a laminated member in which a flow path of gas and / or refrigerant used for an electrochemical reaction is formed on the surface inside the fuel cell The same effect can be obtained by forming a load receiving portion similar to that of the embodiment on the surface and arranging a seal portion similar to that of the embodiment.

E4. Modification 4:
In the first to third embodiments, the seal portion made of the ceramic adhesive is used to ensure the sealing performance of the fuel gas flow path in the single cell and the manifold, but is used to ensure the sealing performance in the refrigerant flow path between the single cells. May be. For example, in the case where a separator in which two separators are stacked is used instead of the three-layer structure separator in which the refrigerant channel is formed in the embodiment, and the refrigerant channel is formed between two separators, the above 2 The present invention can be applied to a seal structure between separators. In such a fuel cell, if a load receiving portion similar to the embodiment is formed at a contact portion where the two separators contact each other, and a seal portion similar to the embodiment is disposed between the two separators, When securing the sealability of the refrigerant and the manifold, the same effect as in the embodiment can be obtained. In addition, the structure for ensuring the sealing property between the two separators that form the inter-unit cell refrigerant passage does not need to ensure insulation.

E5. Modification 5:
In the embodiment, the fuel cell includes the solid oxide electrolyte layer having proton conductivity formed on the hydrogen permeable metal layer, but may be a different type of fuel cell. In the case of a fuel cell that operates in an intermediate temperature range of about 300 to 600 ° C., the same effect can be obtained by improving the durability of the seal portion made of a ceramic adhesive by applying the present invention.

It is a cross-sectional schematic diagram showing the schematic structure of the fuel cell 10 of 1st Example. It is explanatory drawing which expands and shows the A area | region in FIG. 3 is a plan view illustrating a schematic configuration of a frame 45. FIG. 3 is a plan view illustrating a configuration of three metal plates 31 to 33 that constitute a separator 30. FIG. It is explanatory drawing which expands and shows the B area | region in FIG. It is explanatory drawing showing the mode of the specific plane in a fuel cell. It is a cross-sectional schematic diagram showing the structure of the fuel cell of 2nd Example. It is a cross-sectional schematic diagram showing the structure of the fuel cell of 3rd Example. It is a cross-sectional schematic diagram showing the structure of the fuel cell of the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 20 ... Single cell 21 ... Electrolyte layer 22 ... Hydrogen permeable metal layer 24 ... Cathode electrode 26 ... Cathode collector 28 ... Anode collector 30 ... Separator 31-33 ... Metal plate 34 ... Refrigerant hole 35, 36, 56, 57 ... groove 40 ... MEA
42 ... Hole 45 ... Frame 50-55 ... Hole 60, 62 ... Gasket 64 ... Seal 70 ... First recess 72 ... Second recess 160, 162 ... Gasket 164 ... Seal 235, 236, 256, 257 ... Groove 260, 262 ... Gasket 264 ... Seal part 333 ... Metal plate

Claims (15)

A fuel cell,
An electrolyte layer;
A laminated member laminated together with the electrolyte layer, the laminated member comprising a load receiving portion that receives at least part of the pressure applied to the surface of the laminated member in the direction of the lamination;
An adjacent member that is disposed on the laminated member and applies pressure in the direction of the lamination to the surface of the laminated member;
A fuel cell comprising: a seal portion that is formed of a ceramic adhesive and is disposed on the surface of the laminated member and adheres the laminated member and the adjacent member. The fuel cell according to claim 1, wherein
The weight receiving portion is a portion where the laminated member contacts the adjacent member,
The said seal part adhere | attaches between the said lamination | stacking member and the said adjacent member in the vicinity of the said load receiving part. The fuel cell according to claim 2, wherein
The laminated member has a recess filled with the ceramic adhesive on the surface thereof,
The adjacent member is in contact with the laminated member in a region covering the recess. The fuel cell according to claim 2, wherein
The laminated member has a concave portion into which the adjacent member is fitted to form the load receiving portion,
The seal portion is disposed between the surface of the recess and the adjacent member inside the recess. A fuel cell according to any one of claims 1 to 4,
The said adjacent member is a member arrange | positioned between the said laminated member and the other laminated member laminated | stacked adjacent to this laminated member. Fuel cell. A fuel cell according to any one of claims 1 to 5,
The adjacent member is a high elastic modulus member having a higher compression elastic modulus than the laminated member. A fuel cell according to any one of claims 1 to 5,
The adjacent member is an insulating member having an insulating property. The fuel cell according to claim 6 or 7, wherein
The adjacent member is constituted by a mica plate. The fuel cell according to any one of claims 1 to 8,
The laminated member is a frame member that is integrated with the electrolyte layer and supports the electrolyte layer. The fuel cell according to any one of claims 1 to 8,
The said laminated member is a separator which forms a part of wall surface of the flow path of the gas and / or refrigerant | coolant which are provided to an electrochemical reaction. Fuel cell. A fuel cell,
An electrolyte layer;
A plurality of laminated members laminated together with the electrolyte layer, the load receiving portion receiving at least a part of the pressure applied in the direction of the lamination from the laminated member adjacent to the laminated member with respect to the surface of the laminated member A laminated member comprising:
A fuel cell comprising: a seal portion which is formed of a ceramic adhesive and is disposed on the surface of the laminated member and adheres the laminated member and the laminated member adjacent to the laminated member. The fuel cell according to claim 11, wherein
The weight receiving portion is a portion where the laminated member contacts a laminated member adjacent to the laminated member,
The said seal | sticker part adhere | attaches between the said laminated member and the laminated member adjacent to this laminated member in the vicinity of the said load receiving part. The fuel cell according to claim 12, wherein
The laminated member has a recess filled with the ceramic adhesive on the surface thereof,
The laminated member adjacent to the laminated member is in contact with the laminated member in a region covering the recess. The fuel cell according to any one of claims 1 to 13,
The fuel cell has an operating temperature of 300 to 600 ° C. during power generation. 15. The fuel cell according to claim 14, further comprising:
A hydrogen permeable metal layer formed by a hydrogen permeable metal and acting as an anode;
The electrolyte layer is made of a solid oxide having a proton conductor, and is formed on the hydrogen permeable metal layer.

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