JP4661102B2 - Manufacturing method of electrolyte membrane for fuel cell and fuel cell - Google Patents

Description

  The present invention relates to a method for producing an electrolyte membrane having a hydrogen permeable metal layer and a fuel cell using the membrane.

  Conventionally, various structures have been proposed for fuel cells that generate electricity by an electrochemical reaction between hydrogen and air (see Patent Document 1 and Patent Document 2 below). For example, in Patent Document 1 below, there are three types of layers: a fuel electrode of a palladium metal film having gas (hydrogen) permeability, a solid electrolyte having proton conductivity of hydrogen gas, and an air electrode having oxide conductivity. A gas separation membrane fuel cell laminated in this order is disclosed. In such a fuel cell, by using a metal film having hydrogen permeability instead of a ceramic material as a fuel electrode, the thermal expansion coefficient of the material when it is manufactured by stacking three types of layers or when used under high temperature conditions It is said that the generation of cracks based on the difference and delamination between layers are suppressed.

JP-A-4-345762 JP 2004-146337 A

  However, even when the fuel cell having such a configuration is used, peeling may occur between the solid electrolyte and the metal film due to permeation of hydrogen through the metal film during operation. This is because when hydrogen permeates through the metal film, the metal film expands more than the solid electrolyte, and stress in the tensile direction is generated on the side of the joint interface with the solid electrolyte.

  Defects caused by such delamination occur in an electrolyte membrane that is formed by laminating a metal membrane with hydrogen permeability and a solid electrolyte with proton conductivity, which may reduce the performance of fuel cells using the electrolyte membrane. there were.

  In light of these problems, the present invention provides a method of manufacturing an electrolyte membrane that suppresses separation between the solid electrolyte and the metal membrane caused by the expansion of the metal membrane during operation, and a fuel cell including such an electrolyte membrane. For the purpose.

In view of the above problems, the method for manufacturing an electrolyte membrane of the present invention employs the following method. That is, a method for producing an electrolyte membrane used in a fuel cell, in which an electrolyte layer having proton conductivity is laminated on a hydrogen permeable metal layer containing a hydrogen permeable metal, the electrolyte in the hydrogen permeable metal layer A step of applying a residual stress in a compressive direction along the surface of the hydrogen permeable metal layer to the interface side where the layers are laminated , and the step includes subjecting the hydrogen permeable metal layer to plastic deformation due to a stress in a tensile direction. The gist is that it is a step of forming the electrolyte layer while adding .

  According to the method for producing an electrolyte membrane of the present invention, an electrolyte membrane having a residual stress in the compression direction is produced on the electrolyte layer side of the hydrogen permeable metal layer. When hydrogen permeates through the electrolyte membrane thus produced, the tensile stress generated by the expansion of the hydrogen permeable metal layer is reduced by the compressive residual stress applied to the interface side of the hydrogen permeable metal layer. That is, the residual stress in the compression direction works in a direction to cancel the stress in the tensile direction of the hydrogen permeable metal layer, so that the stress generated in the hydrogen permeable metal layer and the electrolyte layer due to hydrogen permeation of the electrolyte membrane is reduced. Therefore, peeling between the hydrogen permeable metal layer and the electrolyte layer due to expansion due to hydrogen permeation can be suppressed.

  Examples of the step of applying compressive residual stress in the method of manufacturing an electrolyte membrane include a step of forming an electrolyte layer while applying plastic deformation in the tensile direction to the hydrogen permeable metal layer itself, and a surface of the hydrogen permeable metal layer. It may be a process of forming an electrolyte layer by applying a so-called mechanical surface treatment such as applying plastic deformation in a tensile direction by a roller or the like. When forming an electrolyte layer while applying plastic deformation in the tensile direction to the hydrogen permeable metal layer itself, the plastic deformation is constrained by the formation of the electrolyte layer, and residual stress can be added to the inside. Through these steps, peeling between the hydrogen permeable metal layer and the electrolyte layer can be suppressed.

  The hydrogen permeable metal layer in the manufacturing method includes a composite hydrogen permeable metal layer in which a plurality of hydrogen permeable metals are laminated, and the step is performed on one hydrogen permeable metal in the composite hydrogen permeable metal layer. A first step of laminating a hydrogen permeable metal to which a compressive residual stress is applied; and after the first step, the one hydrogen permeable metal and a hydrogen permeable metal to which a compressive residual stress is applied. A second step of bonding by a predetermined method, and a third step of forming the electrolyte layer on the hydrogen permeable metal layer to which the residual stress in the compression direction is applied after the second step. It is also good.

  According to such a method for producing an electrolyte membrane, a composite hydrogen permeable metal layer formed by laminating a plurality of hydrogen permeable metals is used on a hydrogen permeable metal layer serving as a base material for forming an electrolyte layer. On the interface side of the composite hydrogen permeable metal layer with the electrolyte layer, a hydrogen permeable metal to which a residual stress in the compression direction is added is laminated. In other words, the composite hydrogen permeable metal layer may have any number of hydrogen permeable metals as much as possible, but a hydrogen permeable metal to which a residual stress in the compression direction is applied in advance is used on the interface side with the electrolyte layer. . Therefore, peeling between the composite hydrogen permeable metal layer and the electrolyte layer can be suppressed.

  In the above manufacturing method, the first step is a step of laminating a hydrogen permeable metal to which a residual stress in the compression direction is applied on the front and back surfaces of the composite hydrogen permeable metal layer, and the third step is the table. It may be a step of forming the electrolyte membrane on one of the hydrogen permeable metals laminated on the back surface.

  According to such a method for manufacturing an electrolyte membrane, the composite hydrogen permeable metal layer is formed by sandwiching a hydrogen permeable metal to which residual stress is not applied from both sides with a hydrogen permeable metal to which residual stress is applied. Therefore, peeling of the composite hydrogen permeable metal layer and the electrolyte layer can be suppressed, and unnecessary stress in the bending direction can be suppressed from acting on the composite hydrogen permeable metal layer.

  In the above manufacturing method, the second step may be a step of activating the metal surface and bonding using a surface activated bonding method of bonding under a predetermined pressure.

  According to this method for producing an electrolyte membrane, a composite hydrogen permeable metal layer is generated using a surface activated bonding method, and an electrolyte layer is formed thereon. By using such a manufacturing method, a plurality of hydrogen permeable metals can be joined together to form a multilayer, which is equivalent to a composite in which a residual stress in the compression direction is added to the inside of one hydrogen permeable metal layer. A hydrogen permeable metal layer can be produced.

The fuel cell according to the present invention is a fuel cell having an electrolyte membrane composed of a hydrogen permeable metal layer containing a hydrogen permeable metal and an electrolyte layer having proton conductivity, wherein the hydrogen permeable metal layer has a tensile direction. By forming the electrolyte layer while adding plastic deformation due to the stress of, the interface of the hydrogen permeable metal layer in the compression direction along the surface of the hydrogen permeable metal layer is formed on the interface side where the electrolyte layer is laminated. A compressive residual stress layer to which residual stress is added can be provided.

  According to such a combustion battery, the compressive residual stress layer is formed on the hydrogen permeable metal layer by using the above manufacturing method and other various manufacturing methods for applying a residual stress to the hydrogen permeable metal surface. Therefore, expansion of the hydrogen permeable metal layer when hydrogen permeates through the compressive residual stress layer can be suppressed, and separation from the electrolyte layer can be suppressed. As a result, performance degradation as a combustion battery can be suppressed.

Hereinafter, embodiments of the present invention will be described in the following order based on examples.
A. Fuel cell structure:
B. Method for producing first electrolyte membrane:
C. Method for producing second electrolyte membrane:
D. Variations:

A. Fuel cell structure:
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a single cell constituting a fuel cell as one embodiment of the present invention. The fuel cell of this embodiment is a fuel cell that generates electric power by an electrochemical reaction between hydrogen separated from the fuel gas and oxygen in an oxidizing gas such as air. This fuel cell is formed by stacking a plurality of single cells 10 shown in FIG. 1 and sandwiching them from both ends by end plates 80. By using a stack structure in which a plurality of single cells 10 are connected in series, power necessary for the system can be taken out.

  The fuel cell having a stack structure is provided with a passage (not shown) for supplying fuel gas, air, and the like. For example, fuel gas stored in a high-pressure tank or air via a compressor is supplied to the passage. Such gas is sufficiently supplied into each single cell 10 through the end plate 80 and the passage. The fuel cell includes a cross flow type and a parallel flow type (including a counter flow type) in which the fuel gas and the oxidizing gas flow orthogonally, but in this embodiment, in order to simplify the description, a parallel flow type is used. It is shown as a flow type.

  As shown in FIG. 1, this single cell 10 is mainly composed of an MEA 100 (Membrane comprising gas separators 60 and 70, which are flow paths in the single cell 10 for fuel gas and oxidizing gas, and an electrolyte membrane and electrodes integrally. -Electrode Assembly) and the like, and the MEA 100 is sandwiched from both sides by gas separators 60 and 70. Although illustration is omitted, in order to adjust the internal temperature of the stack structure, a refrigerant flow path through which a refrigerant for cooling the fuel cell passes is provided between each single cell or each time a predetermined number of single cells are stacked. It may be provided.

  The gas separators 60 and 70 are made of a conductive material such as carbon or metal, and are formed of a dense material that does not allow fuel gas and oxidant gas to permeate. The surface of the gas separator 60 has a concavo-convex shape that forms a fuel gas channel 65 that guides the fuel gas to the inside of the single cell 10, and the surface of the gas separator 70 has an oxidizing gas channel 75 that guides the oxidizing gas to the inside of the unit cell 10. The uneven shape to be formed is formed respectively.

  Of these flow paths of the gas separators 60, 70, the fuel gas flow path 65 contains hydrogen-rich gas obtained by reforming hydrocarbon fuel as fuel gas, and the oxidant gas flow path 75 contains air as oxidizing gas. Are supplied. The gas separators 60 and 70 have a function of collecting electricity generated by an electrochemical reaction between hydrogen in the supplied hydrogen-rich gas and oxygen in the air.

  The MEA 100 is mainly composed of an electrolyte membrane 50 having a hydrogen permeable metal layer 20 that selectively permeates hydrogen and an electrolyte layer 30 having proton conductivity, and a cathode electrode 40, and a hydrogen permeable metal layer. 20, the electrolyte layer 30 and the cathode electrode 40 are laminated in this order.

  The cathode electrode 40 is a layer made of a metal or a ceramic material formed on the electrolyte layer 30 of the electrolyte membrane 50. For example, palladium (Pd) which is a noble metal having a catalytic activity for promoting an electrochemical reaction. Or the like. Furthermore, in order to promote the electrochemical reaction, a catalyst layer such as platinum (Pt) may be provided instead of or together with palladium. In this embodiment, a ceramic electrode material (LaSrO, BaPrCo) is used as the cathode electrode 40.

  The hydrogen permeable metal layer 20 is a layer made of a metal having hydrogen permeability, and can be formed of, for example, palladium (Pd), a Pd alloy, or the like. Alternatively, it can be formed by a multilayer structure in which a palladium (Pd) or Pd alloy layer is formed on vanadium (V), niobium (Nb), tantalum (Ta) or the like or an alloy thereof. Such a hydrogen permeable metal layer 20 has a function as an anode electrode in addition to a function as a hydrogen separation membrane that generates high-purity hydrogen.

The electrolyte layer 30 is a layer made of a solid electrolyte having proton conductivity. For example, BaCeO ₃ , SrCeO ₃ perovskite, pyrochlore, or the like, which is a ceramic solid oxide, can be used. The electrolyte membrane 50 is formed by forming such an electrolyte layer 30 as a thin film on the dense hydrogen permeable metal layer 20.

  A residual stress in the compression direction (compressive residual stress) is applied to the hydrogen permeable metal layer 20 constituting the electrolyte membrane 50 of the present embodiment by performing a predetermined treatment. An arrow P on the hydrogen permeable metal layer 20 shown in FIG. 1 indicates a compressive residual stress. This compressive residual stress P extends from the surface of the hydrogen permeable metal layer 20 to a predetermined depth, and forms a layer 21 of compressive residual stress inside the hydrogen permeable metal layer 20.

  In general, residual stress is generated due to an inconsistent stress field inside an elastic body such as metal, which gives local volume changes and dimensional changes (that is, inhomogeneous plastic deformation) due to external force and heat. . That is, a stress field in the compression direction can be generated by controlling external force, heat, and the like. The electrolyte membrane 50 of this embodiment is formed by laminating an electrolyte layer 30 on the hydrogen permeable metal layer 20 to which such compressive residual stress P is added.

  When the fuel cell having the above configuration is operated, hydrogen (proton) in the hydrogen-rich gas supplied from the outside passes through the electrolyte membrane 50 and reacts with oxygen at the cathode electrode 40. In this reaction process, the hydrogen permeable metal layer 20 expands with the permeation of hydrogen.

  FIG. 2 is an explanatory diagram showing the state of expansion of the electrolyte membrane accompanying hydrogen permeation. As shown in the figure, the hydrogen-permeable metal layer α generally expands (extends) in a direction perpendicular to the direction of hydrogen movement with the permeation of hydrogen under high-temperature operating conditions ranging from 400 ° C. to 500 ° C. Known.

  The hydrogen permeable metal layer α and the electrolyte layer β have different expansion rates due to the permeation of hydrogen, and the hydrogen permeable metal layer α expands greatly compared to the electrolyte layer β. Therefore, the electrolyte layer β is in a state stretched by the hydrogen permeable metal layer α (a state in which the tensile stress T is applied to the bonding interface). For example, when the tensile stress T exceeds the strength of the bonding interface, peeling occurs between the hydrogen permeable metal layer α and the electrolyte layer β.

  Since the hydrogen permeable metal layer 20 of this embodiment has a compressive residual stress P inside thereof, the hydrogen permeable metal layer 20 is restrained from expanding, and the tensile stress T generated at the joint interface due to the expansion. Can be reduced. Therefore, peeling at the joint interface between the hydrogen permeable metal layer α and the electrolyte layer β can be suppressed.

  In other words, by adding the compressive residual stress P, the rate of expansion of the hydrogen permeable metal layer 20 generated during the permeation of hydrogen is reduced, and the expansion rate of the hydrogen permeable metal layer 20 and the electrolyte layer 30 is reduced. Reduce the difference and suppress peeling. As a result, it is possible to suppress the performance degradation of the fuel cell. Below, the manufacturing method of the electrolyte membrane 50 which added the compressive residual stress is demonstrated.

B. Method for producing first electrolyte membrane:
FIG. 3 is a process diagram showing a manufacturing process of the electrolyte membrane 50 to which the compressive residual stress is applied as the first embodiment. In manufacturing the electrolyte membrane 50, first, a hydrogen-permeable metal base material that is the basis of the electrolyte membrane 50 is prepared (step S300). In the first embodiment, palladium (Pd) having a thickness of 100 (μm) is used as the base material S1 for forming the hydrogen permeable metal layer 20.

  Subsequently, the end of the base material S1 is pulled to apply tension to the base material S1 itself (step S310). This tension is a load that causes plastic deformation in the substrate S1, and generates a compressive residual stress in a later step.

The electrolyte layer 30 is formed on the base material S1 in a state where tension is applied (step S320). In the first embodiment, SrCeO ₃ -based perovskite (hereinafter simply referred to as perovskite) is formed as the electrolyte layer 30 to a thickness of 1 (μm).

  For this film formation, a known sol-gel method, which is a kind of liquid phase growth method, is used. The sol-gel method is a method in which a base material surface is coated with a sol-shaped film forming material, dried and fired, and a thin film is obtained through a gel state. In the first embodiment, a perovskite film is formed using this method, but various film forming methods such as a general sputtering method, a physical vapor deposition method (PVD), and a chemical vapor deposition method (CVD) are used. Also good.

  The electrolyte membrane 50 formed by depositing perovskite is in a state where tension is still applied. This tension is removed (step S330), and a series of manufacturing processes is completed.

  The base material S1 of the electrolyte membrane 50 thus manufactured is restrained from uniform plastic deformation by the formation of perovskite in the process of deformation due to the addition of tension. In general, residual stress occurs when free and uniform plastic deformation is constrained. The base material S1 of the first embodiment is formed by depositing a perovskite with a tension applied thereto, thereby holding a compressive residual stress inside (surface) thereof. Through such a manufacturing process, an electrolyte membrane that suppresses expansion of the base material S1 when hydrogen permeates the base material S1 that is the hydrogen permeable metal layer 20, and suppresses peeling at the interface between the base material S1 and the perovskite. 50 can be manufactured.

  Further, the perovskite is formed with a tension applied to the base material S1 serving as the base, and then the tension is removed. This tension is mainly used for plastic deformation, but is also slightly used for elastic deformation of the substrate S1. That is, by removing the tension applied to the electrolyte membrane 50 (base material S1), the electrolyte membrane 50 (base material S1) contracts (returns) within the elastic deformation limit, and compressive stress can be applied to the perovskite itself. This manufacturing method can give compressive residual stress to the base material S1, and can give compressive stress (also referred to as compressive residual stress) to the perovskite.

  Thus, when a predetermined tensile stress is generated in the perovskite (electrolyte layer 30) to which the compressive residual stress has been applied in advance by the operation of the fuel cell, the tensile stress can be relaxed by the internal compressive residual stress. That is, the allowable stress in the tensile direction can be improved.

  On the other hand, when a predetermined compressive stress is generated in the electrolyte layer 30, the internal compressive residual stress is added, so that the stress in the compression direction increases. In general, a material used for the electrolyte layer 30 typified by perovskite has a higher allowable stress in the compression direction than in the tensile direction. Therefore, even if the stress in the compression direction increases, it can be generally allowed. As a result, the electrolyte layer 30 taking into account the strength balance between the tensile direction and the compression direction, and the electrolyte membrane 50 including the electrolyte layer 30 can be formed, and the strength of the entire electrolyte membrane 50 can be improved.

  In addition, although various aspects can be considered for the film-forming apparatus which performs such a manufacturing process, the example was shown in FIG. FIG. 4 is a schematic configuration diagram of a film forming apparatus for manufacturing the electrolyte membrane 50 by the manufacturing method of the first embodiment. In this film forming apparatus, the electrolyte membrane 50 can be continuously formed from the hydrogen-permeable metal base material S1 prepared in a coil shape.

  As shown in the figure, this film forming apparatus 400 mainly includes a film forming unit 410 for forming a perovskite film, a roller 420 for carrying a hydrogen permeable metal base material S1 into the film forming unit 410, and a tension on the base material S1. The tension roller 430 to be added, the holding rollers 425 and 435 that hold the base material S and the electrolyte membrane 50, the holding roll portion 440 that holds the base material S1 in a coil shape, and the winding roll portion 450 that winds the generated electrolyte membrane 50 Etc.

  In this film forming apparatus 400, the electrolyte membrane 50 is sandwiched between the tension roller 430 and the sandwiching roller 435, the substrate S1 is sandwiched between the roller 420 and the sandwiching roller 425, and the roller rotation speed of the tension roller 430 is adjusted. A tension can be applied to the base material S1 in the film forming section 410.

  The base material S1 carried into the film forming unit 410 with tension applied by the roller 420, the tension roller 430, and the sandwiching rollers 425 and 435 is laminated with a perovskite on the upper surface thereof, and the winding roll unit 440 serves as the electrolyte membrane 50. Rolled up. The electrolyte membrane 50 manufactured using such an apparatus is obtained by adding compressive residual stress to the base material S1. By using such an electrolyte membrane 50 for a combustion battery, it is possible to suppress deterioration in the performance of the combustion battery due to the separation of the hydrogen permeable metal layer 20 and the electrolyte layer 30.

C. Method for producing second electrolyte membrane:
FIG. 5 is a process diagram showing a manufacturing process of an electrolyte membrane to which compressive residual stress is applied as a second embodiment. In manufacturing the electrolyte membrane 50, first, a hydrogen-permeable metal base material S2 which is the basis of the electrolyte membrane 50 is manufactured (step S500). In this step, as the base material S2 on which the hydrogen permeable metal layer 20 is formed, a composite metal film is formed which is formed by using vanadium (V) as a base and sandwiching both surfaces thereof with palladium (Pd).

  The composite metal film is manufactured using a surface activated bonding method in which the surfaces of different metals (vanadium, palladium) are activated and bonded.

  FIG. 6 is an explanatory diagram of a grading method for bonding dissimilar metals as one of the surface activated bonding methods. In addition, although base material S2 of 2nd Example is a composite metal film which consists of 3 layers of Pd-V-Pd, in order to simplify description, the joining by two types of dissimilar metals was shown.

  As shown in the figure, in this clad method, the metal material A and the metal material B are pressurized and bonded with a predetermined pressure F. A pressurizing roller 600 is used for pressurization, and a take-up roller 610 is used for moving the joined composite metal film, and a composite metal film is continuously generated.

  The metal material A used here is vanadium (V), the metal material B is palladium (Pd), and a compressive residual stress is applied to the metal material B in advance. As a method for applying compressive residual stress in advance, mechanical surface treatment such as shot peening, heat treatment such as surface quenching, or roll speed of metal material A and metal material B (tension roller of metal material A and metal material B) Various methods can be used, such as applying residual stress by bonding with different loads.

  A predetermined treatment (pretreatment) is performed on the joint surface between the metal material A and the metal material B to which the compressive residual stress is applied before passing through the pressure roller 600. In this pretreatment, argon (Ar) ions or the like are struck against the surfaces of the metal materials A and B in a vacuum atmosphere to remove the deposits, oxide films, etc. existing on the surfaces, thereby exposing the active surfaces. (Surface activation) treatment. The metal materials A and B having the bonding surfaces thus activated are carried into the pressure roller 600, and different metals are bonded to each other. By such pretreatment, the pressure F required for joining can be set to a relatively low pressure.

  The electrolyte layer 30 is formed on the base material S2 as a three-layered metal composite film generated using such a grad method (step S510), and a series of manufacturing steps is completed. The electrolyte layer 30 uses perovskite as in the first manufacturing method, and the sol-gel method is used as the film formation method. As a film forming method, various methods such as physical vapor deposition (PVD) and chemical vapor deposition (CVD) can be used as described above.

  In the second embodiment, compressive residual stress is applied in advance to palladium (Pd) corresponding to the front and back surfaces of the substrate S2. Therefore, as in the first embodiment, it is possible to reduce peeling between the base material S2 and the electrolyte layer 30 when hydrogen permeates the electrolyte membrane 50.

  Further, in the second embodiment, since the compressive residual stress is held on the front and back surfaces of the base material S2, the electrolyte membrane is bent during hydrogen permeation compared to the case where the compressive residual stress is held only on the bonding interface side. Deformation can be suppressed. Of course, even when palladium (Pd) to which compressive residual stress is added only on the interface side with the electrolyte layer 30 is used, it is effective in suppressing peeling. In addition, the difference in the expansion coefficient between different metals (vanadium, palladium) constituting the composite metal film does not have an influence that causes a problem of peeling.

D. Variations:
Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can of course be implemented in various forms without departing from the spirit of the present invention. .

  In the first embodiment, compressive residual stress is applied to the base material S1 in the process of forming the perovskite while applying tension to the base material S1, but it is compressed to the base material S1 before the perovskite film is formed. It is good also as what adds a residual stress.

  For example, the electrolyte membrane deposition apparatus shown in FIG. 4 may be configured to apply compressive residual stress by forcibly rotating the clamping roller 425 in the direction opposite to the conveying direction of the substrate S1. In this case, the surface of the substrate S1 (the side on which the perovskite is formed) is pulled in the rotation direction of the sandwiching roller 425 and locally plastically deformed. Inside the surface layer of the substrate S1, a reaction force in the compression direction that holds down the tensile deformation acts, and this becomes a compressive residual stress. In this way, the perovskite film may be formed while applying compressive residual stress to the surface of the base material S1 before the perovskite film is formed and applying a tension within the elastic limit to the base material S1 as it is.

  In addition, as a method of applying compressive residual stress to the substrate S1 in advance before forming the perovskite, any surface treatment may be performed. For example, the surface of the substrate S1 can be subjected to mechanical surface treatment such as shot peening or heat treatment such as surface quenching to apply compressive residual stress.

  In this example, compressive residual stress is applied to the hydrogen permeable metal layer to suppress the expansion of the hydrogen permeable metal layer during the permeation of hydrogen. For example, an electrolyte membrane containing a hydrogen permeable metal is used. In the case of a fuel cell provided with a supporting frame, a compressive residual stress may be applied to the frame itself to constitute the fuel cell. By doing so, the expansion of the hydrogen permeable metal can be further suppressed.

It is a cross-sectional schematic diagram which shows schematic structure of the single cell which comprises the fuel cell as one Example of this invention. It is explanatory drawing which shows the mode of expansion | swelling of the electrolyte membrane accompanying permeation | transmission of hydrogen. It is process drawing which shows the manufacturing process of the electrolyte membrane which added the compressive residual stress as 1st Example. It is a schematic block diagram of the film-forming apparatus which manufactures an electrolyte membrane with the manufacturing method of 1st Example. It is process drawing which shows the manufacturing process of the electrolyte membrane which added compressive residual stress as 2nd Example. It is explanatory drawing of the grad method which joins a dissimilar metal as one of the surface activation joining methods.

Explanation of symbols

10 ... single cell 20 ... hydrogen permeable metal layer 21 ... compressed residual stress layer 30 ... electrolyte layer 40 ... cathode electrode 50 ... electrolyte membrane 60,70 ... gas separator 65 ... Fuel gas passage 75 ... Oxidation gas passage 80 ... End plate 100 ... MEA
400 ... Film forming apparatus 410 ... Film forming unit 420 ... Roller 425, 435 ... Nipping roller 430 ... Tension roller 440 ... Holding roll unit 450 ... Winding roll unit 600. ..Pressurizing roller 610 ... Winding roller

Claims (5)

A method for producing an electrolyte membrane for use in a fuel cell, wherein an electrolyte layer having proton conductivity is laminated on a hydrogen permeable metal layer containing a hydrogen permeable metal,
The interface side of laminating said electrolyte layer on the hydrogen permeable metal layer, comprising the step of adding the hydrogen-permeable metal layer residual stress in the compressive direction along the surface of,
The said process is a manufacturing method of the electrolyte membrane which is a process of forming the said electrolyte layer, adding the plastic deformation by the stress of a tensile direction to the said hydrogen permeable metal layer . It is a manufacturing method of the electrolyte membrane according to claim 1,
The hydrogen permeable metal layer comprises a composite hydrogen permeable metal layer in which a plurality of hydrogen permeable metals are laminated,
The process includes
A first step of laminating a hydrogen permeable metal to which a residual stress in a compressive direction is added on one hydrogen permeable metal in the composite hydrogen permeable metal layer;
After the first step, the second step of joining the one hydrogen permeable metal and the hydrogen permeable metal to which the residual stress in the compression direction is added by a predetermined method;
After the second step, a third step of forming the electrolyte layer on the hydrogen permeable metal layer to which the residual stress in the compression direction is applied. It is a manufacturing method of the electrolyte membrane according to claim 2 ,
The first step is a step of laminating a hydrogen permeable metal added with a residual stress in the compression direction on the front and back surfaces of the composite hydrogen permeable metal layer,
The third step is a step of forming the electrolyte membrane on one of the hydrogen permeable metals laminated on the front and back surfaces. A method for producing an electrolyte membrane according to claim 2 or claim 3 ,
The second step is a method of manufacturing an electrolyte membrane, which is a step of activating a metal surface and bonding using a surface activated bonding method of bonding under a predetermined pressure. A fuel cell having an electrolyte membrane comprising a hydrogen permeable metal layer containing a hydrogen permeable metal and an electrolyte layer having proton conductivity,
By forming the electrolyte layer while applying plastic deformation due to stress in the tensile direction to the hydrogen permeable metal layer, the hydrogen permeable metal layer is formed on the interface side of the hydrogen permeable metal layer on which the electrolyte layer is laminated. A fuel cell comprising a compressive residual stress layer to which a compressive residual stress is applied along the surface of the layer.

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