Electrochemical cell

Abstract

The utility model discloses an electrochemical cell, its subject is to provide can inhibit the technology of producing bonding bad on the diaphragm and frame member. The electrochemical cell has: the sealing member of frame shape, and the membrane electrode joint is arranged with in the hole portion of the center, and a pair of diaphragm has the first diaphragm and the second diaphragm of clamping sealing member. The first diaphragm has the protruding portion of protruding to the side opposite to the side of the first diaphragm to the sealing member. The sealing member has the region corresponding with the protruding portion, i. e. the first region and the region not corresponding with the protruding portion, i. e. the second region. The thickness of the first region is greater than the thickness of the second region.

Description

Technical Field

[0001] This utility model relates to an electrochemical battery. Background Technology

[0002] A fuel cell unit is known to be constructed by a frame component consisting of a membrane electrode gas diffusion layer junction held in place by a pair of diaphragms in an opening portion (see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-057479 Utility Model Content

[0004] Pressure-sensitive adhesives are sometimes used as frame components. In this case, when the diaphragm is pressed against the frame component, the load applied to the portion of the diaphragm that protrudes toward the frame component differs from the load applied to the portion of the diaphragm that does not protrude toward the frame component, which may result in poor adhesion.

[0005] This utility model was completed to solve the above-mentioned problems and can achieve the following results.

[0006] According to the present invention, an electrochemical battery is provided. The electrochemical battery comprises: a frame-shaped sealing member having a membrane electrode assembly disposed in a central aperture; and a pair of separators having a first separator and a second separator that hold the sealing member. The first separator has a protrusion projecting toward a side opposite to the side of the first separator facing the sealing member. The sealing member has a region corresponding to the protrusion, namely a first region, and a region not corresponding to the protrusion, namely a second region. The thickness of the first region is greater than the thickness of the second region.

[0007] According to this method, the difference between the load applied to the first region of the sealing member corresponding to the protrusion and the load applied to the second region of the sealing member not corresponding to the protrusion can be suppressed. Therefore, poor adhesion in the diaphragm and sealing member can be suppressed.

[0008] Furthermore, this invention can be implemented in various ways, such as by means of a sealing component, a method for manufacturing the sealing component, or a method for manufacturing an electrochemical cell. Attached Figure Description

[0009] Figure 1 This is an explanatory diagram representing the breakdown of an electrochemical cell.

[0010] Figure 2 It is along Figure 1 A sectional view cut along line II-II.

[0011] Figure 3 This is a flowchart illustrating an example of a method for manufacturing an electrochemical battery. Detailed Implementation

[0012] A. Implementation Method 1:

[0013] Figure 1 This is an explanatory diagram showing an electrochemical cell 100 according to one embodiment of the present invention. The electrochemical cell 100 is a solid polymer fuel cell that generates electricity by accepting hydrogen and oxygen as reactant gases. The electrochemical cell 100 includes a power generator 10, a sealing component 20, a pair of first separators 30 and second separators 40, and a manifold 50.

[0014] The power generator 10 comprises an electrolyte membrane (not shown), catalyst layers (not shown) formed adjacent to two sides of the electrolyte membrane, and a gas diffusion layer (not shown) formed adjacent to one side of each catalyst layer. The electrolyte membrane is a solid polymer film that exhibits good proton conductivity in a wetted state. The electrolyte membrane is, for example, an ion exchange membrane made of a fluorinated resin. The catalyst layers comprise a catalyst that promotes the chemical reaction of hydrogen and oxygen and carbon particles supporting the catalyst. The electrolyte membrane and the catalyst layers are collectively referred to as a membrane electrode assembly (MEA).

[0015] Each gas diffusion layer is disposed adjacent to one side of each catalyst layer. The gas diffusion layer is a layer through which the reactant gas used in the electrode reaction diffuses along the surface of the electrolyte membrane, and is composed of a porous diffusion layer substrate. As the diffusion layer substrate, porous substrates with conductivity and gas diffusion properties, such as carbon fiber substrates, graphite fiber substrates, or foamed metals, are used. This electrolyte membrane, catalyst layer, and gas diffusion layer are collectively referred to as a membrane electrode gas-diffusion-layer assembly (MEGA).

[0016] The sealing component 20 is a frame-shaped pressure-sensitive adhesive with a central hole 21. The sealing component 20 is also referred to as a frame component. In this embodiment, the sealing component 20 is an acrylic resin-based adhesive. However, various other natural or synthetic resin-based adhesives, such as urethane resin-based adhesives, silicone resin-based adhesives, and synthetic rubber-based adhesives, can also be used as pressure-sensitive adhesives. A generator 10, including a membrane electrode assembly, is disposed in the hole 21 of the sealing component 20.

[0017] A pair of first diaphragms 30 and second diaphragms 40 are components that hold the sealing member 20, in which the generator 10 is disposed, in the hole 21. The first diaphragm 30 and the second diaphragm 40 are formed, for example, by stamping a metal sheet made of stainless steel or titanium or an alloy thereof.

[0018] The sealing component 20 and the first diaphragm 30 and the second diaphragm 40 have a manifold 50. The manifold 50 connects the sealing component 20 with the first diaphragm 30 and the second diaphragm 40, allowing the flow of reaction gas or cooling water.

[0019] Figure 2 It is Figure 1 A sectional view cut along line II-II. Figure 1 This shows the configuration where the sealing component 20, the first diaphragm 30, and the second diaphragm 40 are engaged. More specifically, it is a cross-sectional view near the manifold orifice 50.

[0020] The first diaphragm 30 has a protrusion 31 that protrudes to a side opposite to the side of the first diaphragm 30 facing the sealing member 20, and a flat portion 32 that does not protrude. The flat portion 32 is bonded to the sealing member 20, and a gas flow path 51 is formed between the protrusion 31 and the sealing member 20. The reaction gas flowing in from the manifold orifice 50 flows through the gas flow path 51 and is supplied to the generator 10.

[0021] The sealing member 20 has a first region 22 corresponding to the protrusion 31 and a second region 23 corresponding to the flat portion 32, which is not corresponding to the protrusion 31. In this embodiment, the hardness of the first region 22 and the hardness of the second region 23 are the same. Furthermore, the thickness T1 of the first region 22 is greater than the thickness T2 of the second region 23. The surface of the sealing member 20 facing the first diaphragm 30 is flat, and the surface of the sealing member 20 facing the second diaphragm 40 has an uneven shape. As a result, a gap 24 is formed between the second region 23 and the second diaphragm 40.

[0022] Figure 3 This is a flowchart illustrating an example of a method for manufacturing an electrochemical cell 100 according to this embodiment. First, in step S100, a sealing member 20, a first separator 30, and a second separator 40, comprising a generator 10 including a membrane electrode assembly, are disposed in the aperture 21. The sealing member 20, in which the generator 10 is disposed in the aperture 21, is disposed on the second separator 40. More specifically, the sealing member 20 is disposed on the second separator 40 such that a gap 24 is formed between the second region 23 and the second separator 40. Furthermore, the first separator 30 is disposed on the sealing member 20. More specifically, the first separator 30 is disposed on the sealing member 20 such that a protrusion 31 faces the first region 22 and a flat portion 32 contacts the second region 23.

[0023] Next, in step S110, the sealing member 20, the first diaphragm 30, and the second diaphragm 40 stacked in step S100 are pressed together. More specifically, in the stacking direction, the sealing member 20, the first diaphragm 30, and the second diaphragm 40 are pressed together from the side of the first diaphragm 30 and the side of the second diaphragm 40, respectively.

[0024] The load applied from the side of the first diaphragm 30 in the first region 22 that is not in contact with the first diaphragm 30 is less than the load applied from the side of the first diaphragm 30 in the second region 23 that is in contact with the first diaphragm 30. However, the thickness T1 of the first region 22 is greater than the thickness T2 of the second region 23, and the first region 22 is in contact with the second diaphragm 40. Therefore, the load applied from the side of the second diaphragm 40 in the first region 22 is greater than the load applied from the side of the second diaphragm 40 in the second region 23 that is not in contact with the second diaphragm 40. Therefore, the load applied to the first region 22 and the load applied to the second region 23 are of the same magnitude.

[0025] The electrochemical cell 100 of this embodiment, as described above, can suppress the difference between the load applied to the first region 22 corresponding to the protrusion 31 and the load applied to the second region 23 not corresponding to the protrusion 31. Therefore, it is possible to suppress poor adhesion between the first diaphragm 30 and the second diaphragm 40 and the sealing member 20.

[0026] B. Other implementation methods:

[0027] (B1) In the above embodiment, the electrochemical cell 100 is a fuel cell unit. However, it is not limited to this; the electrochemical cell 100 may be, for example, a water electrolysis unit, or an electrochemical cell with an electrolyte membrane composed of a solid polymer.

[0028] (B2) In the above embodiment, the sealing member 20, the first diaphragm 30, and the second diaphragm 40 may have through portions serving as positioning references. As a result, when arranging the sealing member 20, the first diaphragm 30, and the second diaphragm 40, positional deviations can be suppressed.

[0029] (B3) In the above embodiment, the hardness of the first region 22 is the same as the hardness of the second region 23. However, it is not limited to this; the hardness of the first region 22 may also be greater than the hardness of the second region 23. In this case, the thickness T1 of the first region 22 may be the same as the thickness T2 of the second region 23.

[0030] (B4) In the above embodiment, the surface of the sealing member 20 opposite to the first diaphragm 30 is flat, and the surface opposite to the second diaphragm 40 has an uneven shape. Not limited thereto, the surface of the sealing member 20 opposite to the first diaphragm 30 may also have an uneven shape.

[0031] (B5) In the above embodiment, the first diaphragm 30 has a protrusion 31 and a flat surface 32. Not limited thereto, the first diaphragm 30 may have: a protrusion 31 that protrudes to the side opposite to the side of the first diaphragm 30 facing the sealing member 20; a recess that protrudes to the side of the first diaphragm 30 facing the sealing member 20; and a flat surface 32 that does not protrude to either side.

[0032] (B6) In the above embodiment, the second diaphragm 40 may have a protrusion that protrudes toward a side opposite to the side of the second diaphragm 40 facing the sealing member 20. The protrusion of the second diaphragm 40 is provided, for example, at a position opposite to the first region 22.

[0033] This utility model is not limited to the above-described embodiments and can be implemented in various structures without departing from its spirit. For example, in order to solve the above-described problems, or to achieve some or all of the above-described effects, the technical features in the embodiments corresponding to the technical features in the various methods described in the summary section of the utility model can be appropriately replaced or combined. Furthermore, if the technical features are not essential to the description in this specification, they can be appropriately deleted.

[0034] Symbol Explanation

[0035] 10-Power generator, 20-Sealing component, 21-Orifice, 22-First region, 23-Second region, 24-Gap, 30-First diaphragm, 31-Protrusion, 32-Flat surface, 40-Second diaphragm, 50-Manifold orifice, 51-Gas flow path, 100-Electrochemical cell.

Claims

1. An electrochemical battery, characterized in that, have: A frame-shaped sealing component, wherein a membrane electrode assembly is disposed in the central orifice; and A pair of diaphragms, having a first diaphragm and a second diaphragm that clamp the sealing member. The first diaphragm has a protrusion that protrudes to a side opposite to the side of the first diaphragm facing the sealing member. The sealing component has a region corresponding to the protrusion, namely a first region, and a region not corresponding to the protrusion, namely a second region. The thickness of the first region is greater than the thickness of the second region.

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