Electrochemical cell

Abstract

An electrolytic cell device (1) is provided with a current collector member (25) and an electrolytic cell (10) that is electrically connected to the current collector member (25). The electrolytic cell (10) is provided with a hydrogen electrode current collector layer (13), a support substrate (12) that is embedded within the hydrogen electrode current collector layer (13) and has through-holes (40), and a hydrogen electrode active layer (14) disposed on the hydrogen electrode current collector layer (13). The current collector member (25) includes overlapping parts (25a) that overlap the through-holes (40) in a thickness direction, and non-overlapping parts (25b) that do not overlap the through-holes (40) in the thickness direction. The density of the overlapping parts (25a) is greater than the density of the non-overlapping parts (25b).

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 plurality of through holes, a plurality of anodes embedded in each of the through holes, an electrolyte layer disposed on the support substrate, and a cathode disposed on the electrolyte layer.

[0003] JP 2013-201061 A

[0004] In the fuel cell described in Patent Document 1, each anode is embedded in each through-hole of the support substrate, so not only is the supply of raw material gas to each anode easily hindered by the support substrate, but current concentration is also likely to occur at each anode.

[0005] Therefore, there is a limit to how much the performance of fuel cells can be improved. This problem is not limited to fuel cells, but occurs in all electrochemical cells, including electrolysis cells.

[0006] An object of the present invention is to provide an electrochemical cell that can improve performance.

[0007] An electrochemical cell device according to a first aspect of the present invention includes a current collecting member and an electrochemical cell electrically connected to the current collecting member. The electrochemical cell includes a current collecting layer, a support substrate embedded in the current collecting layer and having through holes, a first electrode layer disposed on the current collecting layer, a second electrode layer, and an electrolyte layer disposed between the first and second electrode layers. The current collecting member includes an overlapping portion that overlaps with the through holes in the thickness direction and a non-overlapping portion that does not overlap with the through holes in the thickness direction. The density of the overlapping portion is higher than the density of the non-overlapping portion.

[0008] According to a second aspect of the present invention, there is provided an electrochemical cell according to the first aspect, wherein the current collecting layer has a first surface on the current collecting member side. The first surface includes a first overlapping region that overlaps with the through hole in a thickness direction and a first non-overlapping region that does not overlap with the through hole in the thickness direction. The first overlapping region protrudes toward the current collecting member, and the first non-overlapping region protrudes to the opposite side of the current collecting member.

[0009] In a third aspect of the present invention, the second electrode layer has a second surface opposite to the current collecting member, the second surface including a second overlapping region that overlaps with the through hole in the thickness direction and a second non-overlapping region that does not overlap with the through hole in the thickness direction, the second overlapping region protruding toward the current collecting member, and the second non-overlapping region protruding to the side opposite to the current collecting member.

[0010] An electrochemical cell according to a fourth aspect of the present invention is the electrochemical cell according to the third aspect, wherein the flatness of the second surface is smaller than the flatness of the first surface.

[0011] According to the present invention, it is possible to provide an electrochemical cell that can improve performance.

[0012] 1 is a cross-sectional view of an electrolysis cell device according to an embodiment, and FIG. 2 is an enlarged view of a portion of FIG.

[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. 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] The electrolytic cell device 1 is an example of an "electrochemical cell device" according to the present invention. The electrolytic cell 10 is an example of an "electrochemical cell" according to the present invention.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] [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.

[0020] 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 between the beam portions 50 or between the beam portion 50 and the frame portion 60. A buried portion 70 (described later) of the hydrogen electrode current collecting layer 13 is buried in each through hole 40.

[0021] The beams 50 are embedded inside the hydrogen electrode current collecting layer 13. That is, the beams 50 are not exposed on the surface of the hydrogen electrode current collecting layer 13. The outer peripheral surfaces of the beams 50 are covered by the hydrogen electrode current collecting layer 13.

[0022] The beam portion 50 is disposed inside the frame portion 60. The beam portion 50 may be substantially integral with the frame portion 60.

[0023] The beam portion 50 is composed of a plurality of beam members 51. Each beam member 51 is formed in a rod shape. Each beam member 51 shown in FIG. 1 extends along the Y-axis direction. An end of each beam member 51 is connected to the inner peripheral surface of the frame portion 60.

[0024] The beam section 50 may further include one or more beam members extending along the X-axis direction in addition to the beam members 51 shown in Fig. 1. The number and positions of the beam members 51 can be changed as appropriate. The beam section 50 may have a lattice shape as a whole.

[0025] 1, the cross-sectional shape of each beam member 51 according to this embodiment is rectangular, but the cross-sectional shape of each beam member 51 can be changed as appropriate. The cross-sectional shapes of each beam member 51 may be the same or different.

[0026] 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） O[0<x<1]), and a mixed material of two or more of these. These materials generally have low electronic conductivity.

[0027] 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.

[0028] In this embodiment, the electron conductivity of the beam portion 50 is 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 at 800° C. or less. －１ It is possible to make it S / m or less.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] In this embodiment, the electronic conductivity of the frame 60 is 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.

[0034] 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.

[0035] [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, a first layer portion 80, and a second layer portion 90.

[0036] Each embedded portion 70 is embedded in a corresponding through-hole 40 of the support substrate 12. Each embedded portion 70 is continuous with a first layer-shaped portion 80. Each embedded portion 70 is continuous with a second layer-shaped portion 90. Each embedded portion 70 is disposed between the first layer-shaped portion 80 and the second layer-shaped portion 90 in the thickness direction (Z-axis direction) of the support substrate 12.

[0037] The first layer portion 80 is disposed between each embedded portion 70 and the hydrogen electrode active layer 14. The first layer portion 80 is formed in a layer shape so as to cover the entire beam portion 50. The first layer portion 80 is formed integrally with each embedded portion 70. The first layer portion 80 is disposed on the beam portion 50. The first layer portion 80 covers the beam portion 50 on the hydrogen electrode active layer 14 side of the support substrate 12.

[0038] 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 in a layer shape so as to cover the entire beam portion 50. The second layer portion 90 is formed integrally with each embedded portion 70. The second layer portion 90 is disposed on the beam portion 50. 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.

[0039] The hydrogen electrode current collecting layer 13 has a first surface T1 on the side of the current collecting member 25. The detailed configuration of the first surface T1 will be described later.

[0040] The hydrogen electrode current collecting layer 13 is a porous body having electronic conductivity. In this embodiment, the electronic conductivity of the hydrogen electrode current collecting layer 13 is higher than that of the support substrate 12. The hydrogen electrode current collecting layer 13 contains nickel (Ni). In the case of co-electrolysis, Ni is used to generate H 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).

[0041] The hydrogen electrode current collecting layer 13 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.

[0042] 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.

[0043] The method for forming the hydrogen electrode current collecting layer 13 is not particularly limited, and may be tape casting, screen printing, slip casting, dry pressing, etc. The first overlapping region 1a and the first non-overlapping region 1b, which will be described later, may be formed by pressing (e.g., roll pressing) the first surface T1 of the hydrogen electrode current collecting layer 13.

[0044] [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.

[0045] 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.

[0046] 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.

[0047] Hydrogen electrode active layer 14: H2O+2e-→H2+O2- (1)

[0048] The raw material gas is H２ 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.

[0049] 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)

[0050] 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.

[0051] 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.

[0052] 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.

[0053] [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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] [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.

[0059] The reaction prevention layer 16 is made of an ion-conductive material, such as GDC or SDC.

[0060] 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.

[0061] 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.

[0062] [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.

[0063] The oxygen electrode layer 17 has a second surface T2 on the side opposite to the current collecting member 25. The detailed configuration of the second surface T2 will be described later.

[0064] 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.

[0065] Oxygen electrode layer 17: 2O ２－ →O ２ +4e － ...(5)

[0066] 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).

[0067] 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.

[0068] The method for forming the oxygen electrode layer 17 is not particularly limited, and may be tape casting, screen printing, slip casting, dry pressing, etc. The second overlapping region 2 a and the second non-overlapping region 2 b described below may be formed by pressing the second surface T2 of the oxygen electrode layer 17 (e.g., roll pressing).

[0069] (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.

[0070] 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.

[0071] 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).

[0072] 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.

[0073] (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.

[0074] The current collecting member 25 is in contact with the first surface T1 of the hydrogen electrode current collecting layer 13. The detailed configuration of the current collecting member 25 will be described later.

[0075] The current collecting member 25 has electronic conductivity and air permeability. The current collecting member 25 may be made of a porous conductive 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.

[0076] (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.

[0077] 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.

[0078] 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.

[0079] (Detailed Configuration of Current Collecting Member 25) The detailed configuration of the current collecting member 25 will be described with reference to FIG. 2. FIG. 2 is a partially enlarged view of FIG. 1. FIG. 2 illustrates a cross section parallel to the Z-axis direction. FIG. 2 illustrates the shapes of each member with emphasis. Therefore, the actual dimensions and proportions of each member can be changed as appropriate.

[0080] As shown in FIG. 2, the current collecting member 25 has an overlapping portion 25a and a non-overlapping portion 25b.

[0081] The overlapping portion 25a is a region of the current collecting member 25 that overlaps with the through-hole 40 of the support substrate 12 in the thickness direction. The overlapping portion 25a does not overlap with the beam member 51 of the support substrate 12 in the thickness direction.

[0082] The non-overlapping portion 25b is a region of the current collecting member 25 that does not overlap with the through-hole 40 of the support substrate 12 in the thickness direction. The non-overlapping portion 25b overlaps with the beam member 51 of the support substrate 12 in the thickness direction.

[0083] The overlapping portion 25 a and the non-overlapping portion 25 b are connected to each other. The overlapping portion 25 a and the non-overlapping portion 25 b may be integrally formed. The overlapping portion 25 a and the non-overlapping portion 25 b are in contact with the first surface T1 of the hydrogen electrode current collecting layer 13.

[0084] The density of the overlapping portions 25 a is higher than the density of the non-overlapping portions 25 b. This improves the electrical connection between the overlapping portions 25 a of the current collecting members 25 and the embedded portions 70 of the hydrogen electrode current collecting layer 13. This allows for effective use of the embedded portions 70 of the hydrogen electrode current collecting layer 13, which have higher electronic conductivity than the beam portions 50 of the support substrate 12, allowing for more efficient current flow. This improves the performance of the electrolysis cell 10 compared to when the density of the current collecting members 25 is uniform.

[0085] The method for forming the relatively high-density overlapping portion 25a and the relatively low-density non-overlapping portion 25b is not particularly limited, but as will be described later, when the first surface T1 of the hydrogen electrode current collecting layer 13 is uneven, the overlapping portion 25a and the non-overlapping portion 25b can be easily formed by pressing the hydrogen electrode current collecting layer 13 against the current collecting member 25. Alternatively, the overlapping portion 25a and the non-overlapping portion 25b can also be formed by connecting porous conductive materials with different densities in the planar direction.

[0086] (Detailed Configuration of First Surface T1 of Hydrogen Electrode Current Collecting Layer 13) The detailed configuration of the first surface T1 of the hydrogen electrode current collecting layer 13 will be described with reference to FIG.

[0087] The first surface T1 is provided on the current collecting member 25 side of the hydrogen electrode current collecting layer 13. The first surface T1 faces the current collecting member 25. The first surface T1 faces the hydrogen electrode-side space S1. The first surface T1 is part of the surface of the electrolysis cell 10.

[0088] 2, the first surface T1 includes a first overlapping region 1a and a first non-overlapping region 1b. The first surface T1 has projections and recesses formed thereon due to the first overlapping region 1a and the first non-overlapping region 1b.

[0089] The first overlapping region 1a is a region of the first surface T1 that overlaps in the thickness direction with the through-hole 40 of the support substrate 12. The first overlapping region 1a overlaps in the thickness direction with the embedded portion 70 of the hydrogen electrode current collecting layer 13. The first overlapping region 1a does not overlap in the thickness direction with the beam member 51 of the support substrate 12.

[0090] The first overlapping region 1a is in contact with the overlapping portion 25a of the current collecting member 25. In this embodiment, as shown in Fig. 2, the first overlapping region 1a is curved so as to protrude toward the current collecting member 25 side.

[0091] The first non-overlapping region 1b is connected to one end of the first overlapping region 1a in the planar direction. The planar direction is a direction perpendicular to the thickness direction. The first non-overlapping region 1b is a region of the first surface T1 that does not overlap with the through-hole 40 of the support substrate 12 in the thickness direction. The first overlapping region 1a does not overlap with the embedded portion 70 of the hydrogen electrode current collecting layer 13 in the thickness direction. The first non-overlapping region 1b overlaps with the beam member 51 of the support substrate 12 in the thickness direction.

[0092] The first non-overlapping region 1b is in contact with the non-overlapping portion 25b of the current collecting member 25. In this embodiment, as shown in FIG. 2 , the first non-overlapping region 1b is curved so as to protrude to the opposite side of the current collecting member 25.

[0093] The first overlapping region 1a and the first non-overlapping region 1b may be provided corresponding to at least one beam member 51, but may also be provided corresponding to two or more adjacent beam members 51. In this case, the first overlapping region 1a and the first non-overlapping region 1b are repeatedly arranged alternately in the surface direction. As a result, continuous irregularities are periodically formed on the first surface T1.

[0094] (Detailed Structure of Second Surface T2 of Oxygen Electrode Layer 17) The detailed structure of the second surface T2 of the oxygen electrode layer 17 will be described with reference to FIG.

[0095] The second surface T2 is provided on the side of the oxygen electrode layer 17 opposite the current collecting member 25. The second surface T2 is provided on the side opposite the first surface T1. The second surface T2 faces the oxygen electrode-side space S2. The second surface T2 is part of the surface of the electrolysis cell 10.

[0096] 2 , the second surface T2 includes a second overlapping region 2 a and a second non-overlapping region 2 b. The second surface T2 has projections and depressions formed by the second overlapping region 2 a and the second non-overlapping region 2 b. This increases the effective electrode area of ​​the oxygen electrode layer 17 compared to when the second surface T2 is flat, thereby further improving the performance of the electrolysis cell 10.

[0097] The second overlapping region 2a is a region of the second surface T2 that overlaps in the thickness direction with the through-hole 40 of the support substrate 12. The second overlapping region 2a overlaps in the thickness direction with the embedded portion 70 of the hydrogen electrode current collecting layer 13. The second overlapping region 2a does not overlap in the thickness direction with the beam member 51 of the support substrate 12.

[0098] The second non-overlapping region 2b is connected to one end of the second overlapping region 2a in the surface direction. The second non-overlapping region 2b is a region of the second surface T2 that does not overlap with the through-hole 40 of the support substrate 12 in the thickness direction. The second overlapping region 2a does not overlap with the embedded portion 70 of the hydrogen electrode current collecting layer 13 in the thickness direction. The second non-overlapping region 2b overlaps with the beam member 51 of the support substrate 12 in the thickness direction.

[0099] The flatness of the second surface T2 is preferably smaller than the flatness of the first surface T1, which can prevent cracks from occurring in the oxygen electrode layer 17 formed on the layer having the irregularities on its surface (the reaction prevention layer 16 in this embodiment) as shown in FIG.

[0100] The flatness is measured by a method conforming to JIS B0621.

[0101] 2 , continuous undulations are formed on the hydrogen electrode active layer 14 and the electrolyte layer 15. This increases the effective electrode area of ​​the hydrogen electrode active layer 14 compared to when the first surface U1 of the hydrogen electrode active layer 14 that faces the hydrogen electrode current collecting layer 13 is flat, thereby further improving the performance of the electrolysis cell 10. Similarly, this increases the effective electrode area of ​​the hydrogen electrode active layer 14 compared to when the second surface U2 of the hydrogen electrode active layer 14 that faces the electrolyte layer 15 is flat, thereby further improving the performance of the electrolysis cell 10.

[0102] (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.

[0103] [Modification 1] 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.

[0104] [Modification 2] In the above embodiment, the support substrate 12 has the frame portion 60 , but it does not have to have the frame portion 60 .

[0105] [Variation 3] In the above embodiment, the hydrogen electrode current collecting layer 13 has a plurality of embedded portions 70, a first layer portion 80, and a 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.

[0106] [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.

[0107] [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.

[0108] In the above embodiment, the electrolytic cell device 1 has been described as an example of an electrochemical cell device, but the electrochemical cell device is not limited to the electrolytic cell device. The electrochemical cell device is a general term for a device including a current collecting member 25 and an electrochemical cell.

[0109] REFERENCE SIGNS LIST 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, 25a...overlapping portion, 25b...non-overlapping portion, 30...sealing portion, 40...through hole, 50...beam portion, 51...beam member, T1...first surface, 1a...first overlapping region, 1b...first non-overlapping region, 2a...second overlapping region, 2b...second non-overlapping region, 60...frame portion, 70...embedded portion, 80...first layered portion, 90...second layered portion

Claims

1. An electrochemical cell device comprising: a current collecting member; and an electrochemical cell electrically connected to the current collecting member, wherein the electrochemical cell has: a current collecting layer; a support substrate embedded within the current collecting layer and having a 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 current collecting member includes an overlapping portion that overlaps with the through hole in the thickness direction and a non-overlapping portion that does not overlap with the through hole in the thickness direction, and the density of the overlapping portion is higher than the density of the non-overlapping portion.

2. The electrochemical cell device described in claim 1, wherein the current collecting layer has a first surface facing the current collecting member, the first surface including a first overlapping region that overlaps with the through hole in the thickness direction and a first non-overlapping region that does not overlap with the through hole in the thickness direction, the first overlapping region protruding towards the current collecting member side, and the first non-overlapping region protruding to the opposite side of the current collecting member.

3. An electrochemical cell device as described in claim 1 or 2, wherein the second electrode layer has a second surface opposite to the current collecting member, the second surface including a second overlapping region that overlaps with the through hole in the thickness direction and a second non-overlapping region that does not overlap with the through hole in the thickness direction, the second overlapping region protruding towards the current collecting member, and the second non-overlapping region protruding to the side opposite the current collecting member.

4. The electrochemical cell device according to claim 3, wherein the flatness of said second surface is less than the flatness of said first surface.

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