Electrochemical Cell

Abstract

The electrolysis cell (1) includes a metal support (10), a cell main body (20), and a gas seal portion (30). The cell main body (20) is disposed on a first main surface (12) of the metal support (10). The cell main body (20) has an opposing surface (21) facing the first main surface (12). The opposing surface (21) includes a bonding region (21a) bonded to the first main surface (12) and a non-bonding region (21b) not bonded to the first main surface (12). In a plan view of the opposing surface (21), the non-bonding region (21b) is located outside the bonding region (21a).

Description

[Technical field]

[0001] The present invention relates to electrochemical cells. [Background technology]

[0002] 2. Description of the Related Art Conventionally, electrochemical cells (electrolysis cells, fuel cells, etc.) that include a cell body portion disposed on a metal support are known (see, for example, Patent Document 1).

[0003] The metal support has a plurality of communication holes formed in its main surface. The cell body has a first electrode layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer. The first electrode layer covers the plurality of communication holes, and is entirely bonded to the main surface of the metal support. The electrolyte layer covers the first electrode layer, and has an outer edge portion bonded to the main surface of the metal support. The outer edge portion of the electrolyte layer functions as a gas seal portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2020-155337 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned electrochemical cell, if stress is generated in the gas sealing portion (outer edge portion) of the electrolyte layer due to the difference in the amount of volume change between the metal support and the cell main body during an oxidation-reduction cycle or a thermal cycle, cracks or breaks will occur in the gas sealing portion, resulting in a decrease in gas sealing performance.

[0006] Conventionally, it has been believed that in order to prevent cracks and breakage in the gas seal portion, it is necessary to firmly fix the cell main body to the metal support. However, as a result of intensive research by the present inventors, a new finding has been obtained that cracks and breakage in the gas seal portion can be prevented by deliberately not fixing the outer edge of the cell main body to the metal support.

[0007] The present invention has been made based on the above-mentioned new findings, and has an object to provide an electrochemical cell capable of suppressing a decrease in gas sealing performance. [Means for solving the problem]

[0008] An electrochemical cell according to a first aspect of the present invention comprises a metal support having a plurality of communicating holes formed in a main surface, a cell body portion disposed on the main surface and having an opposing surface facing the main surface, and a gas seal portion for sealing between the metal support and the cell body portion. The opposing surface includes a bonding region that is bonded to the main surface and a non-bonding region that is not bonded to the main surface. In a plan view of the opposing surface, the non-bonding region is located outside the bonding region.

[0009] An electrochemical cell according to a second aspect of the present invention is related to the first aspect, wherein, in a plan view of the opposing surface, the non-bonded region surrounds the bonded region.

[0010] An electrochemical cell according to a third aspect of the present invention is related to the first or second aspect, wherein the non-bonded region is spaced from the main surface.

[0011] An electrochemical cell according to a fourth aspect of the present invention is related to any one of the first to third aspects, wherein a width of the non-bonded region in a first cross section is different from a width of the non-bonded region in a second cross section. Each of the first and second cross sections is perpendicular to an outer edge of the main surface in a plan view of the main surface. The first and second cross sections are adjacent to each other in a direction along the outer edge of the main surface. Effect of the Invention

[0012] According to the present invention, it is possible to provide an electrochemical cell capable of suppressing a decrease in gas sealing performance. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a plan view of an electrolysis cell according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a plan view of the opposing surface according to the embodiment. [Figure 4] FIG. 4 is a cross-sectional view taken along line BB of FIG. [Diagram 5] FIG. 5 is a cross-sectional view taken along line CC of FIG. [Figure 6] FIG. 6 is a cross-sectional view of an electrolysis cell according to the first modification. [Figure 7] FIG. 7 is a cross-sectional view of an electrolysis cell according to the third modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (Electrolysis cell 1) Fig. 1 is a plan view of an electrolysis cell 1 according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along line AA in Fig. 1.

[0015] The electrolysis cell 1 is an example of an "electrochemical cell" according to the present invention. The electrolysis cell 1 is a so-called metal-supported electrolysis cell.

[0016] The electrolysis cell 1 is formed in a plate shape extending in the X-axis and Y-axis directions. In this embodiment, the electrolysis cell 1 is formed in a rectangular shape extending in the Y-axis direction when viewed in a plan view from the Z-axis direction perpendicular to the X-axis and Y-axis directions. However, the planar shape of the electrolysis cell 1 is not particularly limited, and may be a polygon other than a rectangle, an ellipse, a circle, or the like.

[0017] As shown in FIG. 2, the electrolysis cell 1 includes a metal support 10, a cell main body 20, a gas seal portion 30, and a flow path member 40.

[0018] [Metal support 10] The metal support 10 supports the cell main body 20. The metal support 10 is formed in a plate shape. The metal support 10 may be in the shape of a flat plate or a curved plate.

[0019] The metal support 10 is only required to be able to support the cell main body 20, and its thickness is not particularly limited, but can be, for example, 0.1 mm or more and 2.0 mm or less.

[0020] As shown in FIG. 2, the metal support 10 has a plurality of communicating holes 11, a first main surface 12 and a second main surface 13.

[0021] Each communication hole 11 penetrates the metal support 10 from the first main surface 12 to the second main surface 13. Each communication hole 11 opens to each of the first main surface 12 and the second main surface 13. In this embodiment, the opening of each communication hole 11 on the first main surface 12 side is covered by a gas diffusion layer 5 described later. The opening of each communication hole 11 on the second main surface 13 side is connected to a flow path 30a described later.

[0022] Each communication hole 11 can be formed by mechanical processing (for example, punching), laser processing, chemical processing (for example, etching), or the like.

[0023] In this embodiment, each communication hole 11 is formed linearly along the Z-axis direction. However, each communication hole 11 may be inclined with respect to the Z-axis direction, and may not be linear. Furthermore, the communication holes 11 may be connected to each other.

[0024] The first main surface 12 is an example of a "main surface" according to the present invention. The first main surface 12 is provided on the opposite side to the second main surface 13. A cell main body 20 is disposed on the first main surface 12. A flow path member 40 is bonded to the second main surface 13.

[0025] The metal support 10 is made of a metal material. For example, the metal support 10 is made of an alloy material containing Cr (chromium). Examples of such metal materials include Fe-Cr alloy steel (stainless steel, etc.) and Ni-Cr alloy steel. The Cr content of the metal support 10 is not particularly limited, but can be set to 4% by mass or more and 30% by mass or less.

[0026] The metal support 10 may contain Ti (titanium) and / or Zr (zirconium). The Ti content in the metal support 10 is not particularly limited, but may be 0.01 mol% or more and 1.0 mol% or less. The Al content in the metal support 10 is not particularly limited, but may be 0.01 mol% or more and 0.4 mol% or less. The metal support 10 may contain Ti as TiO2 (titania) or Zr as ZrO2 (zirconia).

[0027] The metal support 10 may have an oxide film on its surface, which is formed by oxidation of the constituent elements of the metal support 10. A typical example of the oxide film is a chromium oxide film. The chromium oxide film covers at least a portion of the surface of the metal support 10. The chromium oxide film may also cover at least a portion of the inner wall surface of each of the communicating holes 11.

[0028] [Cell body 20] The cell body 20 is disposed on the metal support 10. The cell body 20 is supported by the metal support 10.

[0029] <Configuration of the opposing surface 21> 2, the cell main body 20 has an opposing surface 21. The opposing surface 21 faces the first main surface 12 of the metal support 10 in the thickness direction. The thickness direction is a direction perpendicular to a plane direction parallel to the first main surface 12 of the metal support 10. The plane direction is defined by an approximation straight line of the first main surface 12 obtained by the least squares method in a cross section of the metal support 10 along the Z-axis direction.

[0030] In this specification, two surfaces facing each other means that there is no other member between the two surfaces and that the two surfaces are positioned opposite each other, and this concept is not related to whether the two surfaces are joined or not, or whether the two surfaces are parallel or not.

[0031] As shown in FIG. 2, the opposing surface 21 includes a bonding region 21a and a non-bonding region 21b. The bonding region 21a is a region of the opposing surface 21 that is bonded to the first main surface 12 of the metal support 10. The non-bonding region 21b is a region of the opposing surface 21 that is not bonded to the first main surface 12 of the metal support 10. In this specification, "two surfaces are bonded" means that the two surfaces are in direct contact with each other and that there is a bonding force between the two surfaces. In addition, "two surfaces are not bonded" means that there is no bonding force between the two surfaces, and is a concept that is not related to whether the two surfaces are in direct contact with each other or not.

[0032] Here, FIG. 3 is a plan view of the opposing surface 21. As shown in FIG. 3, in the plan view of the opposing surface 21, the non-bonded region 21b is located outside the bonded region 21a. This allows at least a part of the outer edge of the cell main body 20 to be in a state where it is not restrained by the metal support 10. Conventionally, it has been thought that in order to suppress cracks and breakage in the gas seal portion 30, it is necessary to firmly fix the cell main body 20 to the metal support 10. However, the present inventors have obtained a new finding that cracks and breakage in the gas seal portion 30 can be suppressed by deliberately not fixing the outer edge of the cell main body 20 to the metal support 10. Specifically, it is as follows.

[0033] Oxidation-reduction cycles and thermal cycles may cause volume changes in the metal support 10 and the cell main body 20. In this case, stress is generated in the gas seal portion 30 due to the difference between the amount of volume change in the metal support 10 and the amount of volume change in the cell main body 20. However, the portion of the cell main body 20 that is not restrained by the metal support 10 is deformable in the planar direction, and therefore the stress in the gas seal portion 30 can be absorbed at that portion. As a result, cracks and breakage in the gas seal portion 30 can be suppressed, and therefore the gas sealability of the electrolysis cell 1 can be prevented from decreasing.

[0034] In this embodiment, the bonding region 21a covers all of the communication holes 11 formed in the metal support 10, but some of the communication holes 11 formed in the metal support 10 may not be covered by the bonding region 21a. Therefore, some of the communication holes 11 formed in the metal support 10 may be open toward the non-bonding region 21b.

[0035] As shown in Fig. 3, in a plan view of the opposing surface 21, the non-bonded region 21b preferably surrounds the bonded region 21a. That is, the non-bonded region 21b is preferably formed in a ring shape. This allows the entire outer edge of the cell main body 20 to be in a state where it is not restrained by the metal support 10. Therefore, even if stress in any direction occurs in the gas seal portion 30, the stress of the gas seal portion 30 can be reliably absorbed. Therefore, cracks and breakage of the gas seal portion 30 can be further suppressed.

[0036] As shown in Fig. 2, the non-bonded region 21b is preferably separated from the first main surface 12 of the metal support 10. In other words, the non-bonded region 21b is preferably not in direct contact with the first main surface 12 of the metal support 10. As a result, as shown in Fig. 2, a space T1 is provided between the non-bonded region 21b and the first main surface 12, so that the portion of the cell main body 20 that is not restrained by the metal support 10 can also deform in the thickness direction. Therefore, the stress of the gas seal portion 30 can be absorbed more easily, and cracks and breakage of the gas seal portion 30 can be further suppressed.

[0037] 4 is a cross-sectional view taken along line BB of FIG. 1. FIG. 5 is a cross-sectional view taken along line CC of FIG. 1. FIG. 4 illustrates a first cross-section of the electrolysis cell 1, and FIG. 5 illustrates a second cross-section of the electrolysis cell 1. The first and second cross-sections are each perpendicular to the outer edge 12a of the first main surface 12 of the metal support 10 in a plan view of the first main surface 12. The first and second cross-sections are adjacent cross-sections in a direction along the outer edge 12a of the first main surface 12. In this specification, two cross-sections being adjacent means that the distance between the two cross-sections in the direction along the outer edge 12a of the first main surface 12 is more than 0 mm and not more than 5 mm.

[0038] The width W1 of the non-bonded region 21b in the first cross section (FIG. 4) is different from the width W2 of the non-bonded region 21b in the second cross section (FIG. 5). This means that the distance between the outer edge of the bonded region 21a and the gas seal part 30 is changed. This makes it possible to disperse the stress acting on the outer edge of the bonded region 21a in the planar direction, thereby making it possible to prevent the bonded region 21a from peeling off from the first main surface 12.

[0039] The widths W1 and W2 of the non-bonded region 21b are the sizes of the non-bonded region 21b in the planar direction. It is preferable that the relationship that the width W1 is different from the width W2 holds regardless of the position at which the first and second cross sections are observed, but it is sufficient that the relationship holds in at least one region.

[0040] <Configuration of cell main body 20> As shown in FIG. 2, the cell body 20 has a gas diffusion layer 5, a hydrogen electrode layer 6 (cathode), an electrolyte layer 7, a reaction prevention layer 8, and an oxygen electrode layer 9 (anode).

[0041] The gas diffusion layer 5, hydrogen electrode layer 6, electrolyte layer 7, reaction prevention layer 8, and oxygen electrode layer 9 are laminated in this order in the Z-axis direction from the metal support 10 side. The hydrogen electrode layer 6, electrolyte layer 7, and oxygen electrode layer 9 are essential components, while the gas diffusion layer 5 and reaction prevention layer 8 are optional components.

[0042] [Gas diffusion layer 5] The gas diffusion layer 5 is formed on the first main surface 12 of the metal support 10. The gas diffusion layer 5 is interposed between the metal support 10 and the hydrogen electrode layer 6. A part of the gas diffusion layer 5 may extend into each of the communication holes 11 of the metal support 10.

[0043] In this embodiment, the gas diffusion layer 5 has the above-mentioned bonding region 21a. That is, the bonding region 21a is a region of the surface of the gas diffusion layer 5 that faces the first main surface 12 of the metal support 10.

[0044] The gas diffusion layer 5 is a porous body having gas diffusibility and electrical conductivity. The gas diffusion layer 5 supplies the source gas supplied from each of the communication holes 11 to the hydrogen electrode layer 6, and discharges the product gas generated in the hydrogen electrode layer 6 to each of the communication holes 11.

[0045] The gas diffusion layer 5 includes a conductive material. As the conductive material, a metal material such as Ni (nickel) or Fe (iron) or a conductive ceramic material can be used.

[0046] The gas diffusion layer 5 may include a substrate that supports a conductive material. The substrate may be insulating. As the substrate, YSZ, CSZ, ScSZ, GDC, SDC, (La,Sr)(Cr,Mn)O3, (La,Sr)TiO3, Sr2(Fe,Mo)2O6, (La,Sr)VO3, (La,Sr)FeO3, LDC (lanthanum doped ceria), LSGM (lanthanum gallate), and a mixed material of two or more of these may be used.

[0047] The gas diffusion layer 5 may contain a metal element contained in the metal support 10. This is preferable because it improves the adhesion between the gas diffusion layer 5 and the metal support 10. Note that the above-mentioned conductive material is different from the metal element contained in the metal support 10. Therefore, the conductive material contained in the gas diffusion layer 5 does not need to be contained in the metal support 10.

[0048] The porosity of the gas diffusion layer 5 is not particularly limited, but can be, for example, 20% or more and 40% or less.

[0049] The porosity of the gas diffusion layer 5 is calculated by the following method. First, a cross section of the gas diffusion layer 5 along the Z-axis direction is exposed. Next, a backscattered electron image of the cross section of the gas diffusion layer 5 is obtained at 10,000 times magnification using an SEM device (FE-SEM JSM-7900F manufactured by JEOL Ltd.). Next, the parts displayed in black in the backscattered electron image (corresponding to pores) are identified using image analysis software Image-Pro manufactured by MEDIACYBERNETICS. Then, the porosity of the gas diffusion layer 5 is calculated by dividing the total area of ​​the pores by the total area of ​​the backscattered electron image of the gas diffusion layer 5.

[0050] The thickness of the gas diffusion layer 5 is not particularly limited, but may be, for example, 1 μm or more and 50 μm or less.

[0051] The method for forming the gas diffusion layer 5 is not particularly limited, and may be a firing method, a spray coating method (such as a thermal spray method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method (such as a sputtering method or a pulsed laser deposition method), or a CVD method.

[0052] [Hydrogen electrode layer 6] The hydrogen electrode layer 6 is an example of a "first electrode layer" according to the present invention. The hydrogen electrode layer 6 is formed on the gas diffusion layer 5. The hydrogen electrode layer 6 is disposed between the gas diffusion layer 5 and the electrolyte layer 7.

[0053] In this embodiment, the hydrogen electrode layer 6 has the above-mentioned non-bonded region 21b. That is, the non-bonded region 21b is a region of the surface of the hydrogen electrode layer 6 that faces the first main surface 12 of the metal support 10.

[0054] A source gas is supplied to the hydrogen electrode layer 6 from each of the communication holes 11 via the gas diffusion layer 5. The source gas contains at least H2O.

[0055] When the raw material gas contains only H2O, the hydrogen electrode layer 6 produces H2 from the raw material gas in accordance with the electrochemical reaction of water electrolysis shown in the following formula (1).

[0056] Hydrogen electrode layer 6: H2O+2e - →H2+O 2- (1)

[0057] When the raw gas contains CO in addition to H2O, the hydrogen electrode layer 6 converts H2, CO, and O2 from the raw gas in accordance with the electrochemical reactions of co-electrolysis shown in the following formulas (2), (3), and (4). 2- Generate.

[0058] Hydrogen electrode layer 6: CO2+H2O+4e - →CO+H2+2O 2- (2) Electrochemical reaction of H2O: H2O+2e - →H2+O 2- (3) Electrochemical reaction of CO2: CO2+2e - →CO+O 2- (4)

[0059] The hydrogen electrode layer 6 is a porous body having gas diffusibility and electrical conductivity. A source gas is supplied to the hydrogen electrode layer 6 from the gas diffusion layer 5. The product gas generated in the hydrogen electrode layer 6 is discharged to the gas diffusion layer 5 side.

[0060] The hydrogen electrode layer 6 includes a conductive material. Examples of the conductive material include metal materials such as Ni (nickel) and Fe (iron), and conductive ceramic materials. In the case of co-electrolysis, Ni also functions as a thermal catalyst that promotes the thermal reaction between the generated H2 and the CO2 contained in the raw gas to maintain an appropriate gas composition for methanation, reverse water gas shift reaction, and the like.

[0061] The conductive material exists in an oxide state (e.g., NiO) in an oxidizing atmosphere and in a metallic state (e.g., Ni) in a reducing atmosphere. In this embodiment, it is assumed that the electrolysis cell 1 is exposed to a reducing atmosphere.

[0062] The hydrogen electrode layer 6 includes an oxide ion conductive material such as YSZ, CSZ, ScSZ, GDC, SDC, (La,Sr)(Cr,Mn)O3, (La,Sr)TiO3, Sr2(Fe,Mo)2O6, (La,Sr)VO3, (La,Sr)FeO3, LDC, LSGM, or a mixture of two or more of these materials.

[0063] In this embodiment, the hydrogen electrode layer 6 has a single-layer structure made of a single composition, but may have a multi-layer structure made of different compositions.

[0064] The porosity of the hydrogen electrode layer 6 is not particularly limited, but may be, for example, 20% or more and 40% or less. The porosity of the hydrogen electrode layer 6 is calculated by dividing the total area of ​​the pores by the total area of ​​the backscattered electron image of the hydrogen electrode layer 6, similar to the porosity of the gas diffusion layer 5 described above.

[0065] The thickness of the hydrogen electrode layer 6 is not particularly limited, but may be, for example, 1 μm or more and 500 μm or less.

[0066] The method for forming the hydrogen electrode layer 6 is not particularly limited, and a firing method, a spray coating method, a PVD method, a CVD method, or the like can be used.

[0067] In addition, as shown in FIG. 2, when a space T1 is formed between the non-bonding region 21b of the hydrogen electrode layer 6 and the first main surface 12 of the metal support 10, the molded body of the hydrogen electrode layer 6 may be formed in a state in which the molded body of the gas diffusion layer 5 is surrounded by a square-shaped pore-forming material.

[0068] [Electrolyte layer 7] The electrolyte layer 7 is disposed between the hydrogen electrode layer 6 and the oxygen electrode layer 9. In this embodiment, the reaction prevention layer 8 is disposed between the electrolyte layer 7 and the oxygen electrode layer 9, so that the electrolyte layer 7 is sandwiched between the hydrogen electrode layer 6 and the reaction prevention layer 8.

[0069] The electrolyte layer 7 covers the hydrogen electrode layer 6 and also covers the region of the first main surface 12 of the metal support 10 that is exposed from the gas diffusion layer 5 .

[0070] The electrolyte layer 7 is formed by discharging the O 2- to the oxygen electrode layer 9. The electrolyte layer 7 is made of a dense material having oxide ion conductivity. The electrolyte layer 7 can be made of, for example, YSZ (yttria-stabilized zirconia, e.g., 8YSZ), GDC (gadolinium-doped ceria), ScSZ (scandia-stabilized zirconia), SDC (samarium-doped ceria), LSGM (lanthanum gallate), or the like.

[0071] The porosity of the electrolyte layer 7 is not particularly limited, but may be, for example, 0.1% to 7%. The thickness of the electrolyte layer 7 is not particularly limited, but may be, for example, 1 μm to 100 μm.

[0072] The method for forming the electrolyte layer 7 is not particularly limited, and a baking method, a spray coating method, a PVD method, a CVD method, or the like can be used.

[0073] [Reaction prevention layer 8] The reaction prevention layer 8 is disposed between the electrolyte layer 7 and the oxygen electrode layer 9. The reaction prevention layer 8 is disposed on the opposite side of the electrolyte layer 7 to the hydrogen electrode layer 6. The reaction prevention layer 8 prevents the constituent elements of the electrolyte layer 7 from reacting with the constituent elements of the oxygen electrode layer 9 to form a layer with high electrical resistance.

[0074] The reaction prevention layer 8 is made of an oxide ion conductive material, and may be made of GDC, SDC, or the like.

[0075] The porosity of the reaction prevention layer 8 is not particularly limited, but may be, for example, 0.1% to 50%. The thickness of the reaction prevention layer 8 is not particularly limited, but may be, for example, 1 μm to 50 μm.

[0076] The method for forming the reaction prevention layer 8 is not particularly limited, and a baking method, a spray coating method, a PVD method, a CVD method, or the like can be used.

[0077] [Oxygen electrode layer 9] The oxygen electrode layer 9 is an example of a "second electrode layer" according to the present invention. The oxygen electrode layer 9 is disposed on the opposite side of the hydrogen electrode layer 6 with respect to the electrolyte layer 7. In this embodiment, the reaction prevention layer 8 is disposed between the electrolyte layer 7 and the oxygen electrode layer 9, and therefore the oxygen electrode layer 9 is connected to the reaction prevention layer 8. If the reaction prevention layer 8 is not disposed between the electrolyte layer 7 and the oxygen electrode layer 9, the oxygen electrode layer 9 is connected to the electrolyte layer 7.

[0078] The oxygen electrode layer 9 reacts with O 2 transferred from the hydrogen electrode layer 6 through the electrolyte layer 7 in accordance with the chemical reaction of the following formula (5): 2- produces O2 from

[0079] Oxygen electrode layer 9:2O 2- →O2+4e - (5)

[0080] The oxygen electrode layer 9 is a porous body having oxide ion conductivity and electrical conductivity. The oxygen electrode layer 9 can be made of a composite material of one or more of (La,Sr)(Co,Fe)O3, (La,Sr)FeO3, La(Ni,Fe)O3, (La,Sr)CoO3, and (Sm,Sr)CoO3 and an oxide ion conductive material (such as GDC).

[0081] The porosity of the oxygen electrode layer 9 is not particularly limited, but may be, for example, 20% to 60%. The thickness of the oxygen electrode layer 9 is not particularly limited, but may be, for example, 1 μm to 100 μm.

[0082] The method for forming the oxygen electrode layer 9 is not particularly limited, and a baking method, a spray coating method, a PVD method, a CVD method, or the like can be used.

[0083] [Gas seal part 30] The gas seal part 30 provides a seal between the metal support 10 and the cell main body 20. The gas seal part 30 separates the gas on the hydrogen electrode layer 6 side from the gas on the oxygen electrode layer 9 side. The gas seal part 30 surrounds the outer periphery of the cell main body 20. The gas seal part 30 is connected to the first main surface 12 of the metal support 10 and the electrolyte layer 7 of the cell main body 20.

[0084] The gas seal portion 30 is made of a dense material having gas impermeability. The gas seal portion 30 can be made of, for example, crystallized glass, amorphous glass, spinel oxide, brazing material, or the constituent material of the electrolyte layer 7. Crystallized glass is glass in which the ratio of the "volume occupied by the crystalline phase" to the total volume (degree of crystallization) is 60% or more, and the ratio of the "volume occupied by the amorphous phase and impurities" to the total volume is less than 40%. Examples of such crystallized glass include SiO2-B2O3-based, SiO2-CaO-based, and SiO2-MgO-based.

[0085] When the gas seal portion 30 is made of the same material as the electrolyte layer 7, the gas seal portion 30 may be substantially integral with the electrolyte layer 7.

[0086] [Flow path member 40] The flow path member 40 is joined to the second main surface 13 of the metal support 10. A flow path 30a is formed between the flow path member 40 and the metal support 10. A source gas is supplied to the flow path 30a. The source gas supplied to the flow path 30a is supplied to the hydrogen electrode layer 6 of the cell main body 20 through each communication hole 11 of the metal support 10.

[0087] The flow path member 40 can be made of, for example, an alloy material. The flow path member 40 may be formed of the same material as the metal support 10. In this case, the flow path member 40 may be substantially integrated with the metal support 10.

[0088] The flow path member 40 has a frame 41 and an interconnector 42. The frame 41 is an annular member that surrounds the side of the flow path 30a. The frame 41 is joined to the second main surface 13 of the metal support 10. The interconnector 42 is a plate-shaped member for electrically connecting an external power source or another electrolysis cell to the electrolysis cell 1 in series. The interconnector 42 is joined to the frame 41.

[0089] In this embodiment, the frame 41 and the interconnector 42 are separate members, but the frame 41 and the interconnector 42 may be an integrated member.

[0090] (Modification of the embodiment) Although the embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications are possible without departing from the spirit of the present invention.

[0091] [Variation 1] In the above embodiment, the region of the surface of the gas diffusion layer 5 facing the first main surface 12 of the metal support 10 is the bonding region 21a, but this is not limited to the above. For example, as shown in Fig. 6, when the cell body 20 does not have a gas diffusion layer 5, the region of the surface of the hydrogen electrode layer 6 facing the first main surface 12 of the metal support 10 may include both the bonding region 21a and the non-bonding region 21b.

[0092] [Variation 2] In the above embodiment, the space T1 is provided between the non-bonding region 21b and the first main surface 12, but this is not limited to the above. For example, as shown in Fig. 6, when the non-bonding region 21b and the first main surface 12 are in direct contact with each other, the space T1 does not need to exist.

[0093] [Variation 3] In the above embodiment, the entire area of ​​the surface of the hydrogen electrode layer 6 facing the first main surface 12 of the metal support 10 is the non-bonded region 21b, but this is not limited to the above. For example, as shown in Fig. 7, if part of the gas seal portion 30 enters the gap between the metal support 10 and the cell main body 20, only a part of the area of ​​the surface of the hydrogen electrode layer 6 facing the first main surface 12 of the metal support 10 becomes the non-bonded region 21b.

[0094] [Variation 4] In the above embodiment, the openings of each communication hole 11 on the first main surface 12 side of the metal support 10 are covered by the gas diffusion layer 5, but this is not limited thereto. The gas diffusion layer 5 does not have to cover the openings of each communication hole 11 on the first main surface 12 side. In this case, since through holes communicating with each communication hole 11 are formed in the gas diffusion layer 5, gas can be supplied and exhausted more efficiently via the through holes.

[0095] [Variation 5] In the above embodiment, the hydrogen electrode layer 6 functions as a cathode and the oxygen electrode layer 9 functions as an anode, but the arrangement of the hydrogen electrode layer 6 and the oxygen electrode layer 9 may be reversed.

[0096] [Variation 6] In the above embodiment, the electrolysis cell 1 has been described as an example of an electrochemical cell, but the electrochemical cell is not limited to the electrolysis cell. An electrochemical cell is a general term for an element in which a pair of electrodes are arranged so that an electromotive force is generated from an overall oxidation-reduction reaction in order to convert electrical energy into chemical energy, and an element for converting chemical energy into electrical energy. Therefore, the electrochemical cell includes, for example, a fuel cell that uses oxide ions or protons as a carrier. [Explanation of symbols]

[0097] 1 Electrolysis cell 10 Metal support 11 Communication hole 12 First main surface 12a Outer edge of the first main surface 13 Second main surface 20 Cell body 21 Opposite Surface 21a Junction area 21b Non-bonded area T1 space 5 Gas diffusion layer 6 Hydrogen electrode layer 7 Electrolyte layer 8. Reaction prevention layer 9 Oxygen Polar Layer 30 Gas seal part 40 Flow path member 40a Flow path

Claims

1. a metal support having a plurality of communicating holes formed on a main surface thereof; a cell main body portion disposed on the main surface and having an opposing surface opposing the main surface; a gas seal portion that seals between the metal support and the cell main body portion; Equipped with The facing surface includes a bonding region that is bonded to the main surface and a non-bonding region that is not bonded to the main surface, In a plan view of the opposing surface, the non-bonded region is located outside the bonded region, The bonding region covers all of the openings of the plurality of communication holes. Electrochemical cell.

2. A metal support having a plurality of communicating holes formed on a main surface thereof; a cell main body portion disposed on the main surface and having an opposing surface opposing the main surface; a gas seal portion that seals between the metal support and the cell main body portion; Equipped with The facing surface includes a bonding region that is bonded to the main surface and a non-bonding region that is not bonded to the main surface, In a plan view of the opposing surface, the non-bonded region is located outside the bonded region, In a plan view, the outer edge of the bonding region is wavy. Electrochemical cell.

3. A metal support having a plurality of communicating holes formed on a main surface thereof; a cell main body portion disposed on the main surface and having an opposing surface opposing the main surface; a gas seal portion that seals between the metal support and the cell main body portion; Equipped with The facing surface includes a bonding region that is bonded to the main surface and a non-bonding region that is not bonded to the main surface, In a plan view of the opposing surface, the non-bonded region is located outside the bonded region, In a plan view of the opposing surface, the non-bonded region surrounds the bonded region. Electrochemical cell.

4. A metal support having a plurality of communicating holes formed on a main surface thereof; a cell main body portion disposed on the main surface and having an opposing surface opposing the main surface; a gas seal portion that seals between the metal support and the cell main body portion; Equipped with The facing surface includes a bonding region that is bonded to the main surface and a non-bonding region that is not bonded to the main surface, In a plan view of the opposing surface, the non-bonded region is located outside the bonded region, The width of the non-bonded region in the first cross section is different from the width of the non-bonded region in the second cross section, each of the first and second cross sections is perpendicular to an outer edge of the main surface in a plan view of the main surface; The first and second cross sections are adjacent to each other in a direction along an outer edge of the main surface. Electrochemical cell.

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