Electrochemical cell

Abstract

An electrolysis cell (10) is provided with: a support substrate (12) having a through hole (40); a hydrogen electrode current collector layer (13) having an embedded part (70) embedded in the through hole (40); a hydrogen electrode active layer (14) disposed on the hydrogen electrode current collector layer (13); an oxygen electrode layer (17); and an electrolyte layer (15) disposed between the hydrogen electrode active layer (14) and the oxygen electrode layer (17). The embedded part (70) includes a cavity (71a) that is in contact with a first end region (43) of an inner peripheral surface (41) of the through hole (40).

Description

electrochemical cell

[0001] The present invention relates to electrochemical cells.

[0002] Patent Document 1 discloses an anode-supported fuel cell comprising a support substrate having a through-hole, an anode embedded in the through-hole, an electrolyte layer disposed on the support substrate, and a cathode disposed on the electrolyte layer.

[0003] JP 2013-201061 A

[0004] The fuel cell described in Patent Document 1 has a problem in that the support substrate and the anode have different thermal expansion coefficients, which makes the anode prone to cracking. This problem is not limited to fuel cells, but occurs in all electrochemical cells, including electrolysis cells.

[0005] An object of the present invention is to provide an electrochemical cell that can suppress the occurrence of cracks.

[0006] An electrochemical cell according to a first aspect of the present invention includes a support substrate having a through hole, a current collecting layer having a buried portion buried in the through hole, a first electrode layer disposed on the current collecting layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer, wherein the buried portion includes a void contacting an end region in a thickness direction of an inner circumferential surface of the through hole.

[0007] An electrochemical cell according to a second aspect of the present invention is the electrochemical cell according to the first aspect, wherein, in a plan view of the embedded portion, the through-hole has an R-shaped corner, and the void contacts the corner.

[0008] An electrochemical cell according to a third aspect of the present invention is the electrochemical cell according to the first or second aspect, wherein the current collecting layer has a layer portion that is continuous with the embedded portion and is disposed on the support substrate, and the void has a planar portion that extends along the opening of the through hole on the layer portion side.

[0009] An electrochemical cell according to a fourth aspect of the present invention is the electrochemical cell according to the third aspect, wherein the gap has a curved surface portion facing the flat surface portion.

[0010] An electrochemical cell according to a fifth aspect of the present invention is the electrochemical cell according to the fourth aspect, wherein the curved surface portion is formed in a convex shape in a direction away from the flat surface portion.

[0011] According to the present invention, it is possible to provide an electrochemical cell that can suppress the occurrence of cracks.

[0012] Fig. 1 is a cross-sectional view of an electrolysis cell device according to an embodiment, Fig. 2 is a partially enlarged view of Fig. 1, and Fig. 3 is a cross-sectional view taken along line AA of Fig. 2.

[0013] (Electrolytic Cell Apparatus 1) FIG. 1 is a cross-sectional view showing the configuration of an electrolytic cell apparatus 1 according to an embodiment.

[0014] The electrolytic cell apparatus 1 includes an electrolytic cell 10, a separator 20, a current collecting member 25, and a sealing unit 30. The electrolytic cell 10 is an example of an "electrochemical cell" according to the present invention. A cell stack (not shown) can be formed by stacking a plurality of electrolytic cell apparatuses 1 in the Z-axis direction, which is perpendicular to the X-axis direction and the Y-axis direction.

[0015] 1 , the electrolytic cell 10 includes a support substrate 12, a hydrogen electrode current collecting layer 13, a hydrogen electrode active layer 14, an electrolyte layer 15, a reaction prevention layer 16, and an oxygen electrode layer 17. The hydrogen electrode current collecting layer 13, the hydrogen electrode active layer 14, the electrolyte layer 15, the reaction prevention layer 16, and the oxygen electrode layer 17 are stacked in this order in the Z-axis direction.

[0016] The hydrogen electrode current collecting layer 13 is an example of a "current collecting layer" according to the present invention. The hydrogen electrode active layer 14 is an example of a "first electrode layer" according to the present invention. The oxygen electrode layer 17 is an example of a "second electrode layer" according to the present invention.

[0017] The support substrate 12, the hydrogen electrode current collecting layer 13, the hydrogen electrode active layer 14, the electrolyte layer 15, and the oxygen electrode layer 17 are essential components, while the reaction prevention layer 16 is an optional component.

[0018] [Support Substrate 12] The support substrate 12 functions as a support for the electrolysis cell 10 together with the hydrogen electrode current collecting layer 13. The support substrate 12 has a plurality of through holes 40, beam portions 50, and a frame portion 60.

[0019] Each through hole 40 penetrates the support substrate 12. Each through hole 40 extends along the thickness direction (Z-axis direction) of the support substrate 12. Each through hole 40 is formed inside the beam portion 50 or between the beam portion 50 and the frame portion 60. At least a portion of the hydrogen electrode current collecting layer 13 is embedded in each through hole 40.

[0020] The beam portion 50 is disposed inside the frame portion 60. The beam portion 50 may be substantially integral with the frame portion 60. The cross section of each beam member 51 is rectangular.

[0021] The beam portion 50 is composed of a plurality of beam members 51. The ends of each beam member 51 are connected to the inner peripheral surface of the frame portion 60. In this embodiment, the plurality of beam members 51 are connected to each other in a lattice pattern, but the arrangement of the beam members 51 can be changed as appropriate.

[0022] The beam portion 50 is made of, for example, forsterite (Mg ２ SiO ４ ), magnesium silicate (MgSiO ３ ), zirconia (ZrO ２ , including partially stabilized zirconia), magnesia (MgO), spinel (MgAl ２ O ４ , NiAl ２ O ４ ), yttria stabilized zirconia (YSZ), calcia stabilized zirconia (CSZ), nickel (Ni), nickel oxide (NiO), alumina (Al ２ O ３ ), nickel oxide-magnesia solid solution (Mg ｘ Ni （１－ｘ） 0[0<x<1]) and a mixed material that combines two or more of these.

[0023] The porosity of the beam portion 50 is not particularly limited, but may be, for example, 0.1% to 15%. The porosity of the beam portion 50 may be lower than the porosity of the hydrogen electrode current collecting layer 13. The porosity of the beam portion 50 is preferably 5% or less. This allows the rigidity of the beam portion 50 to be improved.

[0024] The electron conductivity of the beam portion 50 may be lower than that of the hydrogen electrode current collecting layer 13. The beam portion 50 may have electronic insulation. The electron conductivity of the beam portion 50 is not particularly limited, but may be, for example, 10 －１ It is possible to make it S / m or less.

[0025] The method for forming the beam portion 50 is not particularly limited, and may be an extrusion molding method, a tape casting method, a print lamination method, a casting method, a dry press method, or the like.

[0026] The frame 60 is formed in an annular shape. The frame 60 surrounds the beams 50 and the hydrogen electrode current collecting layer 13. In this embodiment, the frame 60 is disposed on the separator 20. The frame 60 is positioned by the sealing portion 30.

[0027] The frame 60 is made of, for example, forsterite (Mg ２ SiO ４ ), magnesium silicate (MgSiO ３ ), zirconia (ZrO ２ , including partially stabilized zirconia), magnesia (MgO), spinel (MgAl ２ O ４ , NiAl ２ O ４ ), yttria stabilized zirconia (YSZ), calcia stabilized zirconia (CSZ), nickel (Ni), nickel oxide (NiO), alumina (Al ２ O ３ ), nickel oxide-magnesia solid solution (Mg ｘ Ni （１－ｘ） 0[0<x<1]), and a mixed material that combines two or more of these. The frame portion 60 may be made of the same material as the beam portion 50. In this case, the frame portion 60 may be substantially integral with the beam portion 50. The frame portion 60 may be made of a material different from that of the beam portion 50.

[0028] The porosity of the frame 60 can be, for example, 0.1% or more and 15% or less. The porosity of the frame 60 may be lower than the porosity of the hydrogen electrode current collecting layer 13. The porosity of the frame 60 is preferably 5% or less. This provides the frame 60 with gas sealing properties, thereby preventing the source gas supplied from the hydrogen electrode side space S1 to the hydrogen electrode current collecting layer 13 from returning to the hydrogen electrode side space S1 via the frame 60.

[0029] The electronic conductivity of the frame 60 may be lower than that of the hydrogen electrode current collecting layer 13. The frame 60 may have electronic insulation. The electronic conductivity of the frame 60 is not particularly limited, but may be, for example, 10 －１ It is possible to make it S / m or less.

[0030] The method for forming the frame portion 60 is not particularly limited, and methods such as extrusion molding, tape casting, print lamination, casting, and dry pressing can be used.

[0031] [Hydrogen Electrode Current Collector Layer 13] The hydrogen electrode current collector layer 13 functions as a support for the electrolysis cell 10 together with the support substrate 12. The hydrogen electrode current collector layer 13 has a plurality of embedded portions 70, first layer portions 80, and second layer portions 90. The embedded portions 70 are an essential component, while the first layer portions 80 and second layer portions 90 are optional components.

[0032] Each embedded portion 70 is embedded in a corresponding through-hole 40 of the support substrate 12. Each embedded portion 70 is continuous with the first layer portion 80. Each embedded portion 70 is continuous with the second layer portion 90. Each embedded portion 70 is disposed between the first layer portion 80 and the second layer portion 90 in the thickness direction (Z-axis direction) of the support substrate 12. The detailed configuration of the embedded portion 70 will be described later.

[0033] The first layer-shaped portion 80 is disposed between each embedded portion 70 and the hydrogen electrode active layer 14. The first layer-shaped portion 80 is formed integrally with each embedded portion 70. The first layer-shaped portion 80 covers the beam portion 50 of the support substrate 12 on the hydrogen electrode active layer 14 side.

[0034] The second layer portion 90 is disposed on the opposite side of the first layer portion 80 with respect to each embedded portion 70. The second layer portion 90 is formed integrally with each embedded portion 70. The second layer portion 90 covers the side of the support substrate 12 opposite the hydrogen electrode active layer 14 of the beam portion 50.

[0035] The hydrogen electrode current collecting layer 13 is a porous body having electronic conductivity. The hydrogen electrode current collecting layer 13 contains nickel (Ni). In the case of co-electrolysis, Ni is used to reduce the amount of H generated. ２ and CO contained in the raw material gas ２ It also functions as a thermal catalyst that promotes the thermal reaction with Ni to maintain an appropriate gas composition for methanation, reverse water gas shift reaction, etc. During operation of the electrolysis cell 10, Ni is basically present in the form of metal Ni, but may also be present in part in the form of nickel oxide (NiO).

[0036] The hydrogen electrode current collecting layer 11 contains a ceramic in addition to nickel (Ni). The ceramic may have ion conductivity. For example, yttria (Y ２ O ３ ), magnesia (MgO), iron oxide (Fe ２ O ３ ), zirconia (ZrO ２ Examples of materials that can be used include yttria-stabilized zirconia (YSZ, partially stabilized zirconia), yttria-stabilized zirconia (YSZ), calcia-stabilized zirconia (CSZ), scandia-stabilized zirconia (ScSZ), gadolinium-doped ceria (GDC), samarium-doped ceria (SDC), and mixed materials of two or more of these.

[0037] The porosity of the hydrogen electrode current collecting layer 13 is not particularly limited, but may be, for example, 20% to 40%. The thickness of the hydrogen electrode current collecting layer 13 is not particularly limited, but may be, for example, 150 μm to 1000 μm. In the Z-axis direction, the thickness of the hydrogen electrode current collecting layer 13 may be greater than the thicknesses of the hydrogen electrode active layer 14, the electrolyte layer 15, the reaction prevention layer 16, and the oxygen electrode layer 17.

[0038] [Hydrogen Electrode Active Layer 14] The hydrogen electrode active layer 14 functions as a cathode. The hydrogen electrode active layer 14 is disposed on the hydrogen electrode current collecting layer 13. The hydrogen electrode active layer 14 is covered with the electrolyte layer 15.

[0039] The source gas is supplied to the hydrogen electrode active layer 14 through the hydrogen electrode current collecting layer 13. In this embodiment, the source gas contains at least H ２ Contains O.

[0040] The raw material gas is H ２ When only O is contained, the hydrogen electrode active layer 14 converts H from the raw material gas according to the electrochemical reaction of water electrolysis shown in the following formula (1): ２ Generate.

[0041] Hydrogen electrode active layer 14: H2O+2e-→H2+O2- (1)

[0042] The raw material gas is H ２ O plus CO ２ In this case, the hydrogen electrode active layer 14 converts H from the source gas according to the co-electrolytic electrochemical reactions shown in the following formulas (2), (3), and (4). ２ , CO and O ２－ Generate.

[0043] Hydrogen electrode active layer 14: CO ２ +H ２ O+4e － →CO+H ２ +20 ２－ ... (2) H ２ Electrochemical reaction of O: H ２ O + 2e － →H ２ +O ２－ ... (3) CO ２ Electrochemical reaction of: CO ２ +2e － →CO+O ２－ ...(4)

[0044] The hydrogen electrode active layer 14 is a porous body having electronic conductivity. The hydrogen electrode active layer 14 may also have ionic conductivity. The hydrogen electrode active layer 14 is made of, for example, YSZ, CSZ, ScSZ, GDC, (SDC), or (La, Sr)(Cr, Mn)O. ３ , (La,Sr)TiO ３ , Sr ２ (Fe, Mo) ２ O ６ , (La, Sr)VO ３ , (La,Sr)FeO ３ , a mixed material of two or more of these, or a composite of one or more of these with NiO.

[0045] The porosity of the hydrogen electrode active layer 14 is not particularly limited, but may be, for example, 20% to 40%. The thickness of the hydrogen electrode active layer 14 is not particularly limited, but may be, for example, 5 μm to 50 μm.

[0046] The method for forming the hydrogen electrode active layer 14 is not particularly limited, and tape casting, screen printing, casting, dry pressing, or the like can be used.

[0047] [Electrolyte Layer 15] The electrolyte layer 15 is disposed between the hydrogen electrode active layer 14 and the oxygen electrode layer 17. In this embodiment, the reaction prevention layer 16 is disposed between the electrolyte layer 15 and the oxygen electrode layer 17, so that the electrolyte layer 15 is sandwiched between the hydrogen electrode active layer 14 and the reaction prevention layer 16.

[0048] The electrolyte layer 15 covers the hydrogen electrode active layer 14. As shown in Fig. 1, the electrolyte layer 15 preferably covers the entire surface of the hydrogen electrode active layer 14. The outer periphery of the electrolyte layer 15 is connected to the frame 60.

[0049] The electrolyte layer 15 absorbs the O generated in the hydrogen electrode active layer 14. ２－ The electrolyte layer 15 has a function of transmitting the ionic current to the oxygen electrode layer 17. The electrolyte layer 15 is a dense body that has ionic conductivity but not electronic conductivity. The electrolyte layer 15 can be made of, for example, YSZ, GDC, ScSZ, SDC, lanthanum gallate (LSGM), or the like.

[0050] The porosity of the electrolyte layer 15 is not particularly limited, but may be, for example, 0.1% to 7%. The thickness of the electrolyte layer 15 is not particularly limited, but may be, for example, 1 μm to 100 μm.

[0051] The method for forming the electrolyte layer 15 is not particularly limited, and tape casting, screen printing, casting, dry pressing, or the like can be used.

[0052] [Reaction prevention layer 16] The reaction prevention layer 16 is disposed between the electrolyte layer 15 and the oxygen electrode layer 17. The reaction prevention layer 16 is disposed on the opposite side of the electrolyte layer 15 from the hydrogen electrode active layer 14. The reaction prevention layer 16 prevents the constituent elements of the electrolyte layer 15 from reacting with the constituent elements of the oxygen electrode layer 17 to form a layer with high electrical resistance.

[0053] The reaction prevention layer 16 is made of an ion-conductive material, such as GDC or SDC.

[0054] The porosity of the reaction prevention layer 16 is not particularly limited, but may be, for example, 0.1% to 50%. The thickness of the reaction prevention layer 16 is not particularly limited, but may be, for example, 1 μm to 50 μm.

[0055] The method for forming the reaction prevention layer 16 is not particularly limited, and tape casting, screen printing, casting, dry pressing, etc. may be used.

[0056] [Oxygen Electrode Layer 17] The oxygen electrode layer 17 functions as an anode. The oxygen electrode layer 17 is disposed on the opposite side of the electrolyte layer 15 from the hydrogen electrode active layer 14. In this embodiment, the reaction prevention layer 16 is disposed between the electrolyte layer 15 and the oxygen electrode layer 17, and therefore the oxygen electrode layer 17 is connected to the reaction prevention layer 16. If the reaction prevention layer 16 is not disposed between the electrolyte layer 15 and the oxygen electrode layer 17, the oxygen electrode layer 17 is connected to the electrolyte layer 15.

[0057] The oxygen electrode layer 17 reacts with O 2 transferred from the hydrogen electrode active layer 14 via the electrolyte layer 15 in accordance with the chemical reaction of the following formula (5): ２－ From O ２ The O generated in the oxygen electrode layer 17 ２ is released into the oxygen electrode side space S2.

[0058] Oxygen electrode layer 17: 2O ２－ →O ２ +4e － ...(5)

[0059] The oxygen electrode layer 17 is a porous material having ionic and electronic conductivity. The oxygen electrode layer 17 is made of, for example, (La, Sr)(Co, Fe)O ３, (La,Sr)FeO ３ , La(Ni,Fe)O ３ , (La,Sr)CoO ３ , and (Sm,Sr)CoO ３ The conductive layer 10 may be made of a composite material of one or more of the above and an ion-conducting material (such as GDC).

[0060] The porosity of the oxygen electrode layer 17 is not particularly limited, but may be, for example, 20% to 60%. The thickness of the oxygen electrode layer 17 is not particularly limited, but may be, for example, 1 μm to 100 μm.

[0061] The method for forming the oxygen electrode layer 17 is not particularly limited, and tape casting, screen printing, casting, dry pressing, or the like can be used.

[0062] (Separator 20) The separator 20 is electrically connected to the hydrogen electrode current collecting layer 13 via the current collecting member 25. The separator 20 has a connection portion 20a that contacts the current collecting member 25.

[0063] The separator 20 is made of a metal material having electronic conductivity. The separator 20 can be made of, for example, an alloy material containing Cr (chromium). Examples of such alloy materials include Fe—Cr alloy steel (stainless steel, etc.) and Ni—Cr alloy steel. The Cr content in the separator 20 is not particularly limited, but can be set to 4% by mass or more and 30% by mass or less.

[0064] The separator 20 may contain Ti (titanium) or Zr (zirconium). The Ti content in the separator 20 is not particularly limited, but can be 0.01 mol % or more and 1.0 mol % or less. The Al content in the separator 20 is not particularly limited, but can be 0.01 mol % or more and 0.4 mol % or less. The separator 20 may contain Ti in the form of TiO ２ (titania), or Zr may be contained as ZrO ２ It may be contained as (zirconia).

[0065] At least a portion of the surface of the separator 20 may be covered with an oxide film formed by oxidation of the constituent elements of the separator 20. A typical example of the oxide film is a chromium oxide film.

[0066] (Current Collector 25) The current collector 25 electrically connects the hydrogen electrode current collecting layer 13 and the connection portion 20a of the separator 20. As shown in FIG. 1 , the current collector 25 is disposed in the hydrogen electrode side space S1 between the hydrogen electrode current collecting layer 13 and the separator 20.

[0067] The current collecting member 25 has electron conductivity and air permeability. The current collecting member 25 may be made of a porous material such as nickel, a nickel alloy, or stainless steel. The size, shape, and position of the current collecting member 25 may be changed as appropriate. For example, in this embodiment, the current collecting member 25 is in contact with the hydrogen electrode current collecting layer 13 and the frame 60, but it does not have to be in contact with the frame 60.

[0068] (Sealing portion 30) The sealing portion 30 positions the frame portion 60 relative to the separator 20. The sealing portion 30 is a dense body. The sealing portion 30 seals the gap between the electrolysis cell 10 and the separator 20. This prevents gases from mixing between the hydrogen electrode side space S1 and the oxygen electrode side space S2.

[0069] In this embodiment, the sealing portion 30 is connected to the electrolyte layer 15 and the frame portion 60 of the support substrate 12, but if the beam portion 50 is not breathable, the sealing portion 30 does not need to be connected to the electrolyte layer 15.

[0070] The sealing portion 30 preferably has electronic insulation properties, which can prevent a short circuit from occurring between the hydrogen electrode current collecting layer 13 and the separator 20. The sealing portion 30 can be made of, for example, glass, glass ceramics (crystallized glass), a composite of glass and ceramics, or the like.

[0071] (Detailed Structure of Embedded Portion 70) The detailed structure of the embedded portion 70 in the hydrogen electrode current collecting layer 13 will be described with reference to Fig. 2. Fig. 2 is a partially enlarged view of Fig. 1. Fig. 2 shows an enlarged cross section of the periphery of one embedded portion 70.

[0072] The embedded portion 70 is embedded in the through-hole 40 of the support substrate 12. The embedded portion 70 includes one or more voids 71. Although two voids 71 ​​(a first void 71a and a second void 71b) are illustrated in FIG. 2, the number of voids 71 ​​is not particularly limited. Therefore, the embedded portion 70 may have only one void 71 (either the first void 71a or the second void 71b).

[0073] Here, the through hole 40 has an inner circumferential surface 41. The inner circumferential surface 41 includes a central region 42, a first end region 43, and a second end region 44. The central region 42, the first end region 43, and the second end region 44 are defined by dividing the inner circumferential surface 41 into three equal parts in the thickness direction. The first end region 43 and the second end region 44 are each an example of an "end region" according to the present invention.

[0074] The central region 42 is located between the first end region 43 and the second end region 44 in the thickness direction (Z-axis direction) of the support substrate 12. The central region 42 is continuous with both the first end region 43 and the second end region 44. The first end region 43 is located on the hydrogen electrode active layer 14 side of the central region 42. The second end region 44 is located on the opposite side of the central region 42 from the first end region 43.

[0075] The first void 71a contacts the first end region 43 of the inner circumferential surface 41 of the through hole 40. This prevents thermal stress caused by the difference in thermal expansion coefficient between the beam member 51 and the embedded portion 70 from concentrating near the corner 51a of the beam member 51. This prevents cracks from occurring in the embedded portion 70 that originate near the corner 51a of the beam member 51.

[0076] In this embodiment, the first gap 71 a does not contact the central region 42 and the second end region 44 of the inner circumferential surface 41 of the through-hole 40 .

[0077] The first gap 71a has a flat surface portion a1 and a curved surface portion a2. The flat surface portion a1 and the curved surface portion a2 are each a part of the inner surface of the first gap 71a.

[0078] The flat portion a1 extends along the opening L1 on the first layer portion 80 side of the through hole 40. The inclusion of the flat portion a1 in the first void 71a can suppress the occurrence of cracks extending from the corners 51a of the beam member 51 to the first layer portion 80. The opening L1 is defined by connecting the corners 51a of the beam member 51 with a straight line on the cross section of FIG.

[0079] The curved surface portion a2 faces the flat surface portion a1. The curved surface portion a2 is formed in a convex shape facing away from the flat surface portion a1. The first void 71a includes the curved surface portion a2, which can suppress the occurrence of cracks originating from the corner where the flat surface portion a1 and the curved surface portion a2 intersect.

[0080] The second void 71b contacts the second end region 44 of the inner circumferential surface 41 of the through hole 40. This prevents thermal stress caused by the difference in thermal expansion coefficient between the beam member 51 and the embedded portion 70 from concentrating near the corner 51b of the beam member 51. This prevents cracks from occurring in the embedded portion 70 that originate near the corner 51b of the beam member 51.

[0081] In this embodiment, the second gap 71 b does not contact the central region 42 and the first end region 43 of the inner circumferential surface 41 of the through-hole 40 .

[0082] Although the size of each of the first and second voids 71 ​​a and 71 b is not particularly limited, the circle-equivalent diameter of each of the first and second voids 71 ​​a and 71 b in a cross section along the thickness direction (Z-axis direction) can be, for example, 10 μm to 100 μm. The circle-equivalent diameter is the diameter of a circle having the same area as the void.

[0083] Here, Fig. 3 is a cross-sectional view taken along the line AA in Fig. 2. Fig. 3 is a plan view of the embedded portion 70 embedded in the through-hole 40 as viewed from the hydrogen electrode active layer 14 side.

[0084] 3, the outline of the through hole 40 has corners 70b formed between two straight lines 70a. In this embodiment, the planar shape of the through hole 40 is quadrangular, and therefore the through hole 40 has four corners 70b. However, the planar shape of the through hole 40 is not limited to a quadrangle, and may be any polygonal shape.

[0085] The corner 70b has an R-shape. The R-shape is a shape in which an imaginary corner formed by the intersection of an extension of one straight line 70a and an extension of the other straight line 70a is chamfered to have a rounded shape.

[0086] The void 71 contacts the rounded corner 70b of the contour of the through hole 40. This prevents thermal stress caused by the difference in thermal expansion coefficient between the beam member 51 and the embedded portion 70 from concentrating near the corner 70b of the through hole 40. This prevents cracks from occurring in the embedded portion 70, starting from near the corner 70b of the through hole 40.

[0087] The hydrogen electrode current collecting layer 13 having the above configuration can be fabricated as follows. First, a desired amount of pore-forming material is placed at a desired position on the inner circumferential surface 41 of each through-hole 40 in the support substrate 12. Next, each through-hole 40 in the support substrate 12 is filled with a paste containing the constituent material of the hydrogen electrode current collecting layer 13. Next, the paste containing the constituent material of the hydrogen electrode current collecting layer 13 is applied to cover one surface of each beam member 51. Next, the paste containing the constituent material of the hydrogen electrode current collecting layer 13 is applied to cover the other surface of each beam member 51. Next, the paste is heat-treated (at 350°C or higher, for 1 hour or longer) to form the hydrogen electrode current collecting layer 13. During this process, the pore-forming material is removed by the heat treatment, thereby forming the first voids 71a and the second voids 71b.

[0088] (Modifications of the Embodiment) Although the embodiment of the present invention has 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.

[0089] [Variation 1] In the above embodiment, the hydrogen electrode current collecting layer 13 has the first layer portion 80 and the second layer portion 90. However, it is not necessary for the hydrogen electrode current collecting layer 13 to have at least one of the first layer portion 80 and the second layer portion 90.

[0090] [Modification 2] In the above embodiment, the hydrogen electrode current collecting layer 13 has a plurality of embedded portions 70, but the number of embedded portions 70 may be one or more.

[0091] [Modification 3] In the above embodiment, the support substrate 12 has the frame portion 60, but it does not have to have the frame portion 60.

[0092] [Variation 4] In the above embodiment, the hydrogen electrode active layer 14 functions as a cathode and the oxygen electrode layer 17 functions as an anode. However, the hydrogen electrode active layer 14 may function as an anode and the oxygen electrode layer 17 may function as a cathode. In this case, the constituent materials of the hydrogen electrode active layer 14 and the oxygen electrode layer 17 are interchanged, and a source gas is passed over the outer surface of the hydrogen electrode active layer 14. The hydrogen electrode current collecting layer 13 functions as an oxygen electrode current collecting layer, but the configuration and function of the oxygen electrode current collecting layer are the same as those of the hydrogen electrode current collecting layer 13 described in the above embodiment.

[0093] [Variation 5] In the above embodiment, the electrolysis cell 10 has been described as an example of an electrochemical cell, but the electrochemical cell is not limited to an 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, electrochemical cells include, for example, fuel cell cells that use oxide ions or protons as carriers.

[0094] DESCRIPTION OF SYMBOLS 1...electrolytic cell device, 10...electrolytic cell, 12...support substrate, 13...hydrogen electrode current collecting layer, 14...hydrogen electrode active layer, 15...electrolyte layer, 16...reaction prevention layer, 17...oxygen electrode layer, 20...separator, 25...current collecting member, 30...sealing portion, 40...through hole, 41...inner peripheral surface, 42...central region, 43...first end region, 44...second end region, 50...beam portion, 51...beam member, 51a...corner portion, 60...frame portion, 70...embedded portion, 70a...straight line, 70b...corner portion, 71...void, 71a...first void, a1...flat portion, a2...curved portion, 71b...second void, 80...first layered portion, 90...second layered portion

Claims

1. A support substrate having through holes, A current collector layer having an embedded portion embedded in the through hole, A first electrode layer is disposed on the current collector layer, The second electrode layer and An electrolyte layer disposed between the first electrode layer and the second electrode layer, Equipped with, The embedded portion includes a gap that is in contact only with the end region in the thickness direction of the inner circumferential surface of the through hole. Electrochemical cell.

2. In a plan view of the buried portion, the through hole has an R-shaped corner, The aforementioned gap is in contact with the corner, The electrochemical cell according to claim 1.

3. The current collector layer has a layered portion that is connected to the buried portion and is arranged on the support substrate, The void has a flat portion that extends along the opening on the layered portion side of the through hole. The electrochemical cell according to claim 1 or 2.

4. The aforementioned void has a curved portion facing the flat portion, The electrochemical cell according to claim 3.

5. The curved portion is formed in a convex shape in the direction away from the flat portion. The electrochemical cell according to claim 4.