Electrochemical cell

Abstract

This electrochemical cell comprises a metal plate, a cell body, a first oxide protrusion and a first non-oxide protrusion. The metal plate has a first main surface, a second main surface, a first through-hole and a second through-hole. The cell body is positioned on the first main surface of the metal plate. The cell body has a first electrode layer, a second electrode layer and an electrolyte layer. The electrolyte later is positioned between the first electrode layer and the second electrode layer. The first oxide protrusion is formed of a material containing an oxide. The first oxide protrusion is located on an inner wall surface of the first through-hole. The first non-oxide protrusion is formed of a material containing a non-oxide. The first non-oxide protrusion is located on an inner wall surface of the second through-hole.

Description

Technical Field

[0001] The present invention relates to an electrochemical cell.

Background Art

[0002] In an electrochemical cell such as an electrolytic cell or a fuel cell, a structure in which a cell main body is supported by a metal plate is known. For example, in the electrochemical cell disclosed in Patent Document 1, an electrode layer, an electrolyte layer, and a counter electrode layer are laminated in this order on a metal plate. The metal plate has through holes for supplying a raw material gas to the electrode layer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the electrochemical cell configured as described above, a raw material gas such as water vapor or fuel gas is supplied to the cell main body through through holes formed in the metal plate. It is preferable to improve the diffusibility of the raw material gas supplied to the cell main body through this through hole. Therefore, an object of the present invention is to improve the diffusibility of the raw material gas supplied to the cell main body.

Means for Solving the Problems

[0005] The electrochemical cell according to the first aspect includes a metal plate, a cell main body, a first oxide protrusion, and a first non-oxide protrusion. The metal plate has a first main surface, a second main surface, a first through-hole, and a second through-hole. The cell main body is disposed on the first main surface of the metal plate. The cell main body has a first electrode layer, a second electrode layer, and an electrolyte layer. The electrolyte layer is disposed between the first electrode layer and the second electrode layer. The first oxide protrusion is made of a material containing an oxide. The first oxide protrusion is disposed on the inner wall surface of the first through-hole. The first non-oxide protrusion is made of a material containing a non-oxide. The first non-oxide protrusion is disposed on the inner wall surface of the second through-hole.

[0006] According to this configuration, the raw material gas flowing in each through-hole collides with the first oxide protrusion or the first non-oxide protrusion, and turbulent flow can be generated. As a result, the diffusibility of the raw material gas supplied to the cell main body through each through-hole can be improved. Even when the flow path through which the raw material gas flows is in an oxidizing atmosphere, the first oxide protrusion is made of a material containing an oxide and does not undergo a phase change, so that turbulent flow can be stably generated. Also, even when the flow path is in a reducing atmosphere, the first non-oxide protrusion is made of a material containing a non-oxide and does not undergo a phase change, so that turbulent flow can be stably generated.

[0007] The electrochemical cell according to the second aspect is configured as follows in the electrochemical cell according to the first aspect. At least one of the first oxide protrusion and the first non-oxide protrusion is annular and extends along the circumferential direction on the inner wall surface. According to this configuration, by making at least one of the first oxide protrusion and the first non-oxide protrusion annular, the symmetry is increased, and the mechanical reliability against the thermal stress generated between each protrusion and the metal plate is improved.

[0008] The electrochemical cell according to the third aspect is configured as follows in the electrochemical cell according to the first or second aspect. At least one of the first oxide protrusion and the first non-oxide protrusion is made of a material having a Young's modulus higher than that of the metal plate. According to this configuration, deformation of each protrusion due to thermal stress can be prevented, and the gas diffusion improvement effect can be maintained.

[0009] The electrochemical cell according to the fourth aspect is configured as follows in the electrochemical cell according to any one of the first to third aspects. The first oxide protrusion and the first non-oxide protrusion are arranged at the end on the second main surface side on the inner wall surface. According to this configuration, the raw material gas flowing through the raw material gas flow path formed on the second main surface side can be efficiently introduced into each through hole of the metal plate.

[0010] The electrochemical cell according to the fifth aspect further includes a second oxide protrusion in the electrochemical cell according to any one of the first to fourth aspects. The second oxide protrusion is composed of a material containing an oxide. The second oxide protrusion is arranged on the inner wall surface of the first through hole closer to the first main surface side than the first oxide protrusion. According to this configuration, by providing the second oxide protrusion in addition to the first oxide protrusion, it becomes easier to generate turbulent flow, and as a result, the gas diffusibility is improved.

[0011] The electrochemical cell according to the sixth aspect further includes a second non-oxide protrusion in the electrochemical cell according to any one of the first to fifth aspects. The second non-oxide protrusion is composed of a material containing a non-oxide. The second non-oxide protrusion is arranged on the inner wall surface of the second through hole closer to the first main surface side than the first non-oxide protrusion. According to this configuration, by providing the second non-oxide protrusion in addition to the first non-oxide protrusion, it becomes easier to generate turbulent flow, and as a result, the gas diffusibility is improved.

[0012] The electrochemical cell according to the seventh aspect further includes a second oxide protrusion in the electrochemical cell according to any one of the first to sixth aspects. The second oxide protrusion is composed of a material containing an oxide. The second oxide protrusion is arranged on the inner wall surface of the second through hole closer to the first main surface side than the first non-oxide protrusion. According to this configuration, even when one of the protrusions is destroyed due to a change in the atmosphere, the other protrusion can exist, so that turbulent flow can be surely generated.

[0013] The electrochemical cell according to the eighth aspect further includes a second non-oxide protrusion in the electrochemical cell according to any one of the first to seventh aspects. The second non-oxide protrusion is made of a material containing a non-oxide. The second non-oxide protrusion is disposed closer to the first main surface side than the first oxide protrusion on the inner wall surface of the first through-hole. According to this configuration, even when one of the protrusions is destroyed due to a change in the atmosphere, the other protrusion can exist, so that turbulent flow can be surely generated.

[0014] The electrochemical cell according to the ninth aspect is configured as follows in the electrochemical cell according to any one of the first to eighth aspects. The first oxide protrusion is made of ceramics.

[0015] The electrochemical cell according to the tenth aspect is configured as follows in the electrochemical cell according to any one of the first to ninth aspects. The first non-oxide protrusion is made of metal.

[0016] The electrochemical cell according to the eleventh aspect is configured as follows in the electrochemical cell according to any one of the first to tenth aspects. The electrochemical cell includes a plurality of first through-holes in which the first oxide protrusions are formed, and a plurality of second through-holes in which the first non-oxide protrusions are formed. The metal plate has a supply port side region and a discharge port side region. The supply port side region is disposed on the supply port side of the flow path of the raw material gas supplied to the cell main body portion through the first through-hole and the second through-hole. The discharge port side region is disposed on the discharge port side of the flow path. The ratio of the first through-hole to the second through-hole is larger in the supply port side region than in the discharge port side region. In this case, it is preferable that the electrochemical cell be an electrolytic cell. When the supply port side of the raw material gas has a higher oxygen partial pressure than the discharge port side of the raw material gas as in the case of an electrolytic cell, by providing more first oxide protrusions on the supply port side and more first non-oxide protrusions on the discharge port side, the occurrence of phase transformation of the protrusions can be suppressed, so that a stable gas diffusion effect can be obtained.

[0017] The electrochemical cell according to the 12th aspect is configured as follows in the electrochemical cell according to any one of the 1st to 10th aspects. The electrochemical cell includes a plurality of first through-holes in which first oxide protrusions are formed, and a plurality of second through-holes in which first non-oxide protrusions are formed. The metal plate has a supply port side region and a discharge port side region. The supply port side region is disposed on the supply port side of the flow path of the raw material gas supplied to the cell main body portion through the first through-holes and the second through-holes. The discharge port side region is disposed on the discharge port side of the flow path. The ratio of the first through-holes to the second through-holes is smaller in the supply port side region than in the discharge port side region. In this case, it is preferable that the electrochemical cell be a fuel cell. When the oxygen partial pressure on the discharge port side of the raw material gas is higher than that on the supply port side as in the case of a fuel cell, by providing more first oxide protrusions on the discharge port side and more first non-oxide protrusions on the supply port side, the occurrence of the phase transformation of the protrusions can be suppressed, so that a stable gas diffusion effect can be obtained.

Effects of the Invention

[0018] According to the present invention, the diffusibility of the raw material gas supplied to the cell main body portion can be improved.

Brief Description of the Drawings

[0019]

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Embodiments for Carrying Out the Invention

[0020] Hereinafter, the electrolytic cell (an example of an electrochemical cell) according to the present embodiment will be described with reference to the drawings. In the present embodiment, a solid oxide electrolytic cell (SOEC) will be described as an example of the electrolytic cell. FIG. 1 is a cross-sectional view showing the electrolytic cell. In the following description, the solid oxide electrolytic cell may also be abbreviated as a "cell".

[0021] As shown in FIG. 1, the cell 100 has a metal plate 2, a cell main body portion 3, a first oxide protrusion 4, and a first non-oxide protrusion 5. The cell 100 further includes a flow path member 6.

[0022] [Flow Path Member] The flow path member 6 is joined to the metal plate 2. The flow path member 6 has a flow path 61. The flow path 61 is formed on the surface of the flow path member 6 that faces the metal plate 2. In the present embodiment, the flow path 61 is formed on the upper surface of the flow path member 6. The flow path 61 opens toward the metal plate 2. The flow path 61 is connected to a manifold (not shown). In the present embodiment, for example, the raw material gas is supplied from left to right in the flow path 61.

[0023] The flow path member 6 can be made of, for example, an alloy material. The flow path member 6 may be formed of the same material as the metal plate 2.

[0024] The flow path member 6 has a frame body 62 and an interconnector 63. The frame body 62 is an annular member that surrounds the side of the flow path 61. The frame body 62 is joined to the metal plate 2. The interconnector 63 is a plate-like member that electrically connects the electrolytic cell 100 in series with an external power source or another electrolytic cell. The interconnector 63 is joined to the frame body 62.

[0025] In the flow path member 6 according to the present embodiment, the frame body 62 and the interconnector 63 are separate members, but the frame body 62 and the interconnector 63 may be formed of one member.

[0026] [Metal plate] The metal plate 2 supports the cell main body portion 3. In the present embodiment, the metal plate 2 is formed in a plate shape. The metal plate 2 may be flat or curved. The metal plate 2 only needs to be able to maintain the strength of the cell 100, and its thickness is not particularly limited, but can be, for example, 0.1 mm or more and 2.0 mm or less.

[0027] The metal plate 2 has a first main surface 21, a second main surface 22, and a plurality of through holes 23. The first main surface 21 of the metal plate 2 supports the cell main body portion 3. The second main surface 22 of the metal plate 2 faces the flow path 61. In the present embodiment, the upper surface of the metal plate 2 is the first main surface 21, and the lower surface of the metal plate 2 is the second main surface 22. The frame body 62 of the flow path member 6 is connected to the second main surface 22 of the metal plate 2.

[0028] As shown in FIG. 2, the metal plate 2 is rectangular in plan view. Note that the metal plate 2 may have other shapes such as circular shape. The plurality of through holes 23 are arranged along the longitudinal direction and the short side direction of the metal plate 2. The plurality of through holes 23 are formed in a region of the metal plate 2 that is joined to a hydrogen electrode layer 31 described later. The through hole 23 opens to the first main surface 21. Further, the through hole 23 also opens to the second main surface 22. That is, the through hole 23 extends in the thickness direction of the metal plate 2 from the first main surface 21 to the second main surface 22 of the metal plate 2. The through hole 23 penetrates the metal plate 2 in the thickness direction. The through hole 23 communicates with the flow path 61 of the flow path member 6. The raw material gas flowing through the flow path 61 is supplied to the hydrogen electrode layer 31 through the through hole 23.

[0029] The through hole 23 is substantially circular in plan view. The area of the through hole 23 in plan view is, for example, 0.00005 mm 2 or more and 1 mm 2 or less. Further, the diameter of the through hole 23 can be, for example, 10 μm or more and 1000 μm or less. Note that the through hole 23 may be rectangular in plan view. Further, the height of the through hole 23 is larger than the thickness of the hydrogen electrode layer 31. The height of the through hole 23 can be, for example, 100 μm or more and 2000 μm or less. Note that the height of the through hole 23 means the dimension in the vertical direction in FIG. 1.

[0030] The through hole 23 can be formed by machining (for example, punching), laser processing, or chemical processing (for example, etching). As the metal plate 2, porous metal can also be used to provide gas permeability.

[0031] The plurality of through holes 23 include a plurality of first through holes 23a and a plurality of second through holes 23b. The first through hole 23a is a through hole in which a first oxide protrusion 4 is formed on the inner wall surface among the plurality of through holes 23. Further, the second through hole 23b is a through hole in which a first non-oxide protrusion 5 is formed on the inner wall surface among the plurality of through holes 23.

[0032] The metal plate 2 is made of a metal material. For example, the metal plate 2 is made of an alloy material containing Cr (chromium). As such a metal material, Fe-Cr alloy steel (such as stainless steel) or Ni-Cr alloy steel can be used. The content rate of Cr in the metal plate 2 is not particularly limited, but can be 4 mass% or more and 30 mass% or less.

[0033] The metal plate 2 may contain Ti (titanium) or Zr (zirconium). The content rate of Ti in the metal plate 2 is not particularly limited, but can be 0.01 mol% or more and 1.0 mol% or less. The content rate of Zr in the metal plate 2 is not particularly limited, but can be 0.01 mol% or more and 0.4 mol% or less. The metal plate 2 may contain Ti as TiO 2 (titania), or may contain Zr as ZrO 2 (zirconia).

[0034] The metal plate 2 may have an oxide film on its surface. Specifically, the metal plate 2 may have a chromium oxide film on its surface. The oxide film covers at least a part of the surface of the metal plate 2. The oxide film only needs to cover at least a part of the surface of the metal plate 2, but may cover substantially the entire surface. Also, the oxide film may cover the inner wall surface of the through-hole 23. The thickness of the oxide film is not particularly limited, but can be, for example, 0.1 μm or more and 20 μm or less.

[0035] [Cell main body part] As shown in FIG. 1, the cell main body part 3 is disposed on the first main surface 21 of the metal plate 2. The cell main body part 3 has a hydrogen electrode layer 31 (cathode), an electrolyte layer 32, a reaction prevention layer 33, and an oxygen electrode layer 34 (anode). The hydrogen electrode layer 31, the electrolyte layer 32, the reaction prevention layer 33, and the oxygen electrode layer 34 are laminated in this order from the metal plate 2 side. Note that the cell main body part 3 may not have the reaction prevention layer 33. Also, the hydrogen electrode layer 31 is an example of the first electrode layer of the present invention, and the oxygen electrode layer 34 is an example of the second electrode layer of the present invention.

[0036] [Hydrogen electrode layer] The hydrogen electrode layer 31 is supported by the metal plate 2. Specifically, the hydrogen electrode layer 31 is disposed on the first main surface 21 of the metal plate 2. The thickness t of the hydrogen electrode layer 31 can be, for example, 1 μm or more and 100 μm or less. The hydrogen electrode layer 31 is thinner than the metal plate 2. As shown in FIG. 2, the hydrogen electrode layer 31 is provided so as to cover a region of the metal plate 2 where a plurality of through-holes 23 are provided.

[0037] The hydrogen electrode layer 31 is preferably porous. The porosity of the hydrogen electrode layer 31 is not particularly limited, but can be, for example, 20% or more and 70% or less.

[0038] The hydrogen electrode layer 31 is composed of a porous material having electronic conductivity. The hydrogen electrode layer 31 may have oxide ion conductivity. The hydrogen electrode layer 31 is, for example, 8 mol% yttria-stabilized zirconia (8YSZ), calcia-stabilized zirconia (CSZ), scandia-stabilized zirconia (ScSZ), gadolinium-doped ceria (GDC), samarium-doped ceria (SDC), (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 , and a mixed material formed by combining two or more of these, or a composite of one or more of these and NiO.

[0039] The method for forming the hydrogen electrode layer 31 is not particularly limited, and it can be formed by a firing method, a spray coating method, a PVD method, a CVD method, or the like.

[0040] The hydrogen electrode layer 31 is configured to generate hydrogen by an electrolysis reaction. A raw material gas is supplied to the hydrogen electrode layer 31 through the through-holes 23. The raw material gas contains at least H 2 O.

[0041] When the raw material gas is H 2When only O is included, the hydrogen electrode layer 31 generates H from the raw material gas according to the electrochemical reaction of water electrolysis shown in the following formula (1). 2 is generated. · Hydrogen electrode layer 31: H 2 O + 2e - → H 2 + O 2- ···(1)

[0042] When the raw material gas contains CO in addition to H 2 O, the hydrogen electrode layer 31 generates H 2 , CO and O 2 from the raw material gas according to the electrochemical reactions of co-electrolysis shown in the following formulas (2), (3), and (4). 2- is generated. · Hydrogen electrode layer 31: CO 2 + H 2 O + 4e - → CO + H 2 + 2O 2- ···(2) · Electrochemical reaction of H 2 O: H 2 O + 2e - → H 2 + O 2- ···(3) · Electrochemical reaction of CO 2 : CO 2 + 2e - → CO + O 2- ···(4)

[0043] [Electrolyte layer] As shown in FIG. 1, the electrolyte layer 32 is disposed between the hydrogen electrode layer 31 and the oxygen electrode layer 34. In this embodiment, since the cell main body 3 has the reaction prevention layer 33, the electrolyte layer 32 is inserted between the hydrogen electrode layer 31 and the reaction prevention layer 33. The thickness of the electrolyte layer 32 is not particularly limited, but can be, for example, 3 μm or more and 50 μm or less.

[0044] In this embodiment, the electrolyte layer 32 is arranged to cover the entire hydrogen electrode layer 31. The outer peripheral portion of the electrolyte layer 32 is joined to the first main surface 21 of the metal plate 2. Thereby, since the airtightness between the hydrogen electrode layer 31 side and the oxygen electrode layer 34 side can be ensured, there is no need to separately seal between the metal plate 2 and the electrolyte layer 32.

[0045] The electrolyte layer 32 transmits O 2- generated in the hydrogen electrode layer 31 to the oxygen electrode layer 34. The electrolyte layer 32 has oxide ion conductivity. The electrolyte layer 32 is composed of a dense material. The porosity of the electrolyte layer 32 is about 0% or more and 7% or less. The electrolyte layer 32 is a fired body composed of a dense material having ion conductivity and no electron conductivity. The electrolyte layer 32 can be composed of, for example, 8YSZ, GDC, ScSZ, SDC, LSGM (lanthanum gallate), etc.

[0046] The method for forming the electrolyte layer 32 is not particularly limited, and it can be formed by a firing method, a spray coating method, a PVD method, a CVD method, etc.

[0047] [Reaction prevention layer] The reaction prevention layer 33 is arranged on the electrolyte layer 32. The reaction prevention layer 33 is inserted between the electrolyte layer 32 and the oxygen electrode layer 34. The thickness of the reaction prevention layer 33 is not particularly limited, but can be, for example, 1 μm or more and 50 μm or less. The reaction prevention layer 33 suppresses the formation of a reaction layer with a large electrical resistance due to the reaction between the constituent material of the oxygen electrode layer 34 and the constituent material of the electrolyte layer 32.

[0048] The reaction prevention layer 33 is composed of a material having oxide ion conductivity. The reaction prevention layer 33 can be composed of a ceria-based material such as GDC or SDC. The porosity of the reaction prevention layer 33 is not particularly limited, but can be, for example, 0.1% or more and 50% or less. The method for forming the reaction prevention layer 33 is not particularly limited, and it can be formed by a firing method, a spray coating method, a PVD method, a CVD method, etc.

[0049] [Oxygen electrode layer] The oxygen electrode layer 34 is disposed on the side opposite to the hydrogen electrode layer 31 with respect to the electrolyte layer 32. In the present embodiment, since the cell 100 has the reaction prevention layer 33, the oxygen electrode layer 34 is disposed on the reaction prevention layer 33.

[0050] The oxygen electrode layer 34 is preferably porous. The porosity of the oxygen electrode layer 34 is not particularly limited, but can be, for example, 20% or more and 70% or less. The thickness of the oxygen electrode layer 34 is not particularly limited, but can be, for example, 1 μm or more and 100 μm or less.

[0051] The oxygen electrode layer 34 is composed of a porous material having oxide ion conductivity and electron conductivity. The oxygen electrode layer 34 is, 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 and can be composed of a composite of one or more of these and an oxide ion conducting material (such as GDC).

[0052] The method for forming the oxygen electrode layer 34 is not particularly limited, and it can be formed by a firing method, a spray coating method, a PVD method, a CVD method, or the like.

[0053] The oxygen electrode layer 34 generates O 2- from O 2 transmitted from the hydrogen electrode layer 31 through the electrolyte layer 32 according to the chemical reaction of the following formula (5). ·Oxygen electrode layer 34: 2O 2- →O 2 + 4e - ···(5)

[0054] [First oxide protrusion] FIG. 3 is a cross-sectional view showing details around the first through-hole 23a in which the first oxide protrusion 4 is formed, and FIG. 4 is a bottom view of the first through-hole 23a as viewed from the second main surface side. As shown in FIGS. 3 and 4, the first oxide protrusion 4 is disposed on the inner wall surface of the first through-hole 23a. The first oxide protrusion 4 is annular and extends along the circumferential direction on the inner wall surface of the first through-hole 23a. That is, the first oxide protrusion 4 extends continuously along the circumferential direction. Note that the first oxide protrusion 4 may extend intermittently along the circumferential direction. Also, the first oxide protrusion 4 may not extend along the circumferential direction. Note that the first oxide protrusion 4 may not be formed directly on the inner wall surface of the first through-hole 23a. For example, when an oxide film is formed on the inner wall surface of the first through-hole 23a, the first oxide protrusion 4 is formed on the oxide film.

[0055] The first oxide protrusion 4 is disposed at the end on the second main surface 22 side on the inner wall surface of the first through-hole 23a. Specifically, the first through-hole 23a has an end on the first main surface 21 side and an end on the second main surface 22 side in the axial direction. And the first oxide protrusion 4 is not formed at the end on the first main surface 21 side among the both axial ends of the first through-hole 23a, but is formed at the end on the second main surface 22 side. Note that the first oxide protrusion 4 may be disposed on the first main surface 21 side.

[0056] The first oxide protrusion 4 protrudes from the inner wall surface of the first through-hole 23a toward the center. The height of the first oxide protrusion 4 is, for example, 1 μm or more and 100 μm or less. Note that the height of the first oxide protrusion 4 is the dimension from the inner wall surface of the first through-hole 23a toward the center.

[0057] The first oxide protrusion 4 is made of a material having a higher Young's modulus than the metal plate 2. The first oxide protrusion 4 is made of a material containing an oxide. Specifically, the first oxide protrusion 4 is made of a material consisting only of an oxide. For example, the first oxide protrusion 4 is made of oxide ceramics. More specifically, the first oxide protrusion 4 is Cr 2 O 3 , (Mn,Cr) 3 O 4, (Mn, Cr, Fe) 3 O 4 , (Cr, Fe) 2 O 3 , Fe 2 O 3 , Fe 3 O 4 , Al 2 O 3 , ZrO 2 , or CeO 2 and the like can be used to form it.

[0058] Note that the first oxide protrusion 4 may be made of the same material as the oxide film formed on the inner wall surface of the first through-hole 23a. In this case, the protruding portion with respect to the other portions is the first oxide protrusion 4. That is, the height of the first oxide protrusion 4 is greater than the thickness of the oxide film. Also, the height of the first oxide protrusion 4 in this case is defined as the height from the inner wall surface of the first through-hole 23a.

[0059] The first oxide protrusion 4 can be formed by applying an oxide paste along the circumferential direction on the inner wall surface of the first through-hole 23a using a precision nozzle dispenser and firing the oxide paste. Alternatively, the first oxide protrusion 4 can also be formed by locally laser-heating the inner wall surface of the first through-hole 23a along the circumferential direction to form a thick oxide film.

[0060] As shown in FIG. 5, the first oxide protrusion 4 is preferably formed in the through-hole 23 disposed in the supply port side region A1. For example, the region A of the metal plate 2 where the through-hole 23 is formed is divided into three equal parts along the direction in which the raw material gas flows (supply direction). For example, in FIG. 5, since the raw material gas flows from left to right, the region A is divided into three equal parts along the left-right direction. Then, the region close to the supply port of the raw material gas (the left region in FIG. 5) is defined as the supply port side region A1. Note that the region close to the discharge port of the raw material gas (the right region in FIG. 5) is defined as the discharge port side region A2, and the region between the supply port side region A1 and the discharge port side region A2 is defined as the central region A3.

[0061] The first oxide protrusion 4 is preferably formed in all the through-holes 23 in the supply port side region A1, but it is not necessary to be formed in all the through-holes 23 in the supply port side region A1. For example, the first oxide protrusion 4 is preferably formed in 50% or more of the through-holes 23 in the supply port side region A1. In addition, the first oxide protrusion 4 is preferably formed in at least 10% or more of the through-holes 23 in the supply port side region A1. In addition, the first oxide protrusion 4 may be formed in the through-holes 23 in the discharge port side region A2 or the central region A3.

[0062] [First non-oxide protrusion] FIG. 6 is a cross-sectional view showing details around the second through-hole 23b in which the first non-oxide protrusion 5 is formed, and FIG. 7 is a bottom view of the second through-hole 23b in which the first non-oxide protrusion 5 is formed as viewed from the second main surface side.

[0063] As shown in FIGS. 6 and 7, the first non-oxide protrusion 5 is disposed on the inner wall surface of the second through-hole 23b. The first non-oxide protrusion 5 is annular and extends along the circumferential direction on the inner wall surface of the second through-hole 23b. That is, the first non-oxide protrusion 5 extends continuously along the circumferential direction. In addition, the first non-oxide protrusion 5 may extend intermittently along the circumferential direction. Also, the first non-oxide protrusion 5 may not extend along the circumferential direction. In addition, the first non-oxide protrusion 5 may not be directly formed on the inner wall surface of the second through-hole 23b. For example, when an oxide film is formed on the inner wall surface of the second through-hole 23b, the first non-oxide protrusion 5 is formed on the oxide film.

[0064] The first non-oxide protrusion 5 is disposed at the end on the second main surface 22 side on the inner wall surface of the second through-hole 23b. Specifically, the second through-hole 23b has an end on the first main surface 21 side and an end on the second main surface 22 side in the axial direction. And the first non-oxide protrusion 5 is not formed at the end on the first main surface 21 side among the both ends in the axial direction of the second through-hole 23b, but is formed at the end on the second main surface 22 side. In addition, the first non-oxide protrusion 5 may be disposed on the first main surface 21 side.

[0065] The first non-oxide protrusion 5 protrudes from the inner wall surface of the second through-hole 23b toward the center. The height of the first non-oxide protrusion 5 is, for example, 1 μm or more and 100 μm or less. Note that the height of the first non-oxide protrusion 5 is the dimension from the inner wall surface of the second through-hole 23b toward the center.

[0066] The first non-oxide protrusion 5 is made of a material containing a non-oxide. Specifically, the first non-oxide protrusion 5 is made of a material containing a metal. For example, the first non-oxide protrusion 5 is made of a metal. Note that the first non-oxide protrusion 5 may contain an oxide in addition to the metal. Specifically, the first non-oxide protrusion 5 may be configured to cover the surface of the oxide with a metal. Specifically, examples of the metal contained in the first non-oxide protrusion 5 include Fe, Co, Ni, or Cu. Examples of the oxide contained in the first non-oxide protrusion 5 include Cr 2 O 3 , (Mn, Cr) 3 O 4 , (Mn, Cr, Fe) 3 O 4 , (Cr, Fe) 2 O 3 , Fe 3 O 4 , Al 2 O 3 , ZrO 2 , and CeO 2 and the like. The first non-oxide protrusion 5 may be made of a material having a higher Young's modulus than the metal plate 2.

[0067] The first non-oxide protrusion 5 can be formed by applying a non-oxide paste onto the inner wall surface of the second through-hole 23b along the circumferential direction by a precision nozzle dispenser and firing it in an atmosphere controlled so that the non-oxide is not oxidized. Alternatively, the first non-oxide protrusion 5 can also be formed by selectively laser-sintering the non-oxide paste applied onto the inner wall surface of the second through-hole 23b.

[0068] As shown in Fig. 5, the first non-oxide protrusion 5 is preferably formed in the through-hole 23 disposed in the discharge port side region A2. The first non-oxide protrusion 5 is preferably formed in all the through-holes 23 in the discharge port side region A2, but it is not necessary to be formed in all the through-holes 23 in the discharge port side region A2. For example, the first non-oxide protrusion 5 is preferably formed in 50% or more of the through-holes 23 in the discharge port side region A2. In addition, the first non-oxide protrusion 5 is preferably formed in at least 10% or more of the through-holes 23 in the discharge port side region A2. The first non-oxide protrusion 5 may be formed in the through-hole 23 in the supply port side region A1 or the central region A3.

[0069] The number of the first through-holes 23a is larger than the number of the second through-holes 23b in the supply port side region A1 and smaller than the number of the second through-holes 23b in the discharge port side region A2. That is, the ratio of the first through-holes 23a to the second through-holes 23b in the supply port side region A1 is larger than the ratio of the first through-holes 23a to the second through-holes 23b in the discharge port side region A2. This ratio can be calculated, for example, as shown by the dashed-dotted line in Fig. 5, by cutting the metal plate 2 along the arrangement direction of the plurality of through-holes 23 and the supply direction of the raw material gas and on the cut surface. Note that the second through-hole 23b may not be formed in the supply port side region A1. Also, the first through-hole 23a may not be formed in the discharge port side region A2.

[0070] [Modification Example] As described above, the embodiments of the present invention have been described, but the present invention is not limited thereto, and various changes can be made without departing from the spirit of the present invention.

[0071] (a) In the above embodiment, the hydrogen electrode layer 31 was disposed on the metal plate 2, but the configuration of the cell main body 3 is not limited thereto. For example, as shown in FIG. 8, the oxygen electrode layer 34 may be disposed on the metal plate 2. In this case, the oxygen electrode layer 34, the reaction prevention layer 33, the electrolyte layer 32, and the hydrogen electrode layer 31 are arranged in this order from the side of the metal plate 2. The electrolyte layer 32 is formed so as to cover the oxygen electrode layer 34 and the reaction prevention layer 33. Note that the reaction prevention layer 33 may not be formed.

[0072] (b) As shown in FIG. 9, the electrolytic cell 100 may further include a second oxide protrusion 7. The second oxide protrusion 7 is disposed closer to the first main surface 21 side than the first oxide protrusion 4 on the inner wall surface of the first through hole 23a. For example, the second oxide protrusion 7 is disposed at the central portion in the axial direction of the first through hole 23a. The second oxide protrusion 7 is disposed at a distance from the hydrogen electrode layer 31. Also, the second oxide protrusion 7 is disposed at a distance from the first oxide protrusion 4.

[0073] Similar to the first oxide protrusion 4, the second oxide protrusion 7 is formed on the inner wall surface of the first through hole 23a. The height of the second oxide protrusion 7 may be formed lower than the height of the first oxide protrusion 4. The second oxide protrusion 7 is made of a material containing an oxide. The second oxide protrusion 7 is made of a material having a higher Young's modulus than the metal plate 2. The second oxide protrusion 7 can be made of the same material as the first oxide protrusion 4. Also, the second oxide protrusion 7 can be formed in the same manner as the first oxide protrusion 4.

[0074] As shown in FIG. 10, the second oxide protrusion 7 may be disposed closer to the first main surface 21 side than the first non-oxide protrusion 5 on the inner wall surface of the second through hole 23b. For example, the second oxide protrusion 7 is disposed at the central portion in the axial direction of the second through hole 23b. The second oxide protrusion 7 is disposed at a distance from the hydrogen electrode layer 31. Also, the second oxide protrusion 7 is disposed at a distance from the first non-oxide protrusion 5.

[0075] (c) As shown in FIG. 11, the electrolytic cell 100 may further have a second non-oxide protrusion 8. The second non-oxide protrusion 8 is disposed closer to the first main surface 21 than the first non-oxide protrusion 5 on the inner wall surface of the second through-hole 23b. For example, the second non-oxide protrusion 8 is disposed at the central portion in the axial direction of the second through-hole 23b. The second non-oxide protrusion 8 is disposed at a distance from the hydrogen electrode layer 31. Also, the second non-oxide protrusion 8 is disposed at a distance from the first non-oxide protrusion 5.

[0076] Similar to the first non-oxide protrusion 5, the second non-oxide protrusion 8 is formed on the inner wall surface of the second through-hole 23b. The height of the second non-oxide protrusion 8 may be formed lower than the height of the first non-oxide protrusion 5. The second non-oxide protrusion 8 is composed of a material containing a non-oxide. The second non-oxide protrusion 8 can be composed of the same material as the first non-oxide protrusion 5. Also, the second non-oxide protrusion 8 can be formed in the same manner as the first non-oxide protrusion 5.

[0077] As shown in FIG. 12, the second non-oxide protrusion 8 may be disposed closer to the first main surface 21 than the first oxide protrusion 4 on the inner wall surface of the first through-hole 23a. For example, the second non-oxide protrusion 8 is disposed at the central portion in the axial direction of the first through-hole 23a. The second non-oxide protrusion 8 is disposed at a distance from the hydrogen electrode layer 31. Also, the second non-oxide protrusion 8 is disposed at a distance from the first oxide protrusion 4.

[0078] (d) The first oxide protrusion 4 and the first non-oxide protrusion 5 are not limited to the above-described shapes. For example, as shown in FIG. 13, the cross section of the first oxide protrusion 4 and the first non-oxide protrusion 5 may be triangular, or may have other shapes. Also, the second oxide protrusion 7 and the second non-oxide protrusion 8 are not limited to the above-described shapes, and as shown in FIG. 14, the cross section may be triangular, or may have other shapes.

[0079] (e) As shown in Fig. 15, the hydrogen electrode layer 31 may enter into the through-hole 23. In this case, the hydrogen electrode layer 31 may be filled only in a part of the through-hole 23 as shown in Fig. 15, may be filled in the whole through-hole 23, or may protrude from the through-hole 23 to the second main surface 22 side.

[0080] (f) In the above embodiment, the first oxide protrusion 4 and the first non-oxide protrusion 5 are arranged at the end on the second main surface 22 side of the through-hole 23, but the positions of the first oxide protrusion 4 and the first non-oxide protrusion 5 are not limited thereto. For example, the first oxide protrusion 4 and the first non-oxide protrusion 5 may be arranged at the central portion in the axial direction of the through-hole 23, or may be arranged at other positions.

[0081] (g) In the above embodiment, the first oxide protrusion 4 and the first non-oxide protrusion 5 are not arranged on the second main surface 22 of the metal plate 2, but the configuration of the first oxide protrusion 4 is not limited thereto. For example, as shown in Fig. 16, the first oxide protrusion 4 and the first non-oxide protrusion 5 may be formed on the inner wall surface of the through-hole 23 and also on the second main surface 22. In this case, the first oxide protrusion 4 and the first non-oxide protrusion 5 are arranged so as to cover the corner portion 221 formed by the inner wall surface of the through-hole 23 and the second main surface 22.

[0082] (h) In the above embodiment, an electrolytic cell 100 has been described as an example of the electrochemical cell, but the electrochemical cell may be other than the electrolytic cell. For example, it may be a fuel cell such as a solid oxide fuel cell. In this case, the first electrode layer can be used as a fuel electrode (anode), and the second electrode layer can be used as an air electrode (cathode).

[0083] In this case, the first oxide protrusion 4 is preferably formed in the through-hole 23 disposed in the discharge port side region A2. Further, the first non-oxide protrusion 5 is preferably formed in the through-hole 23 disposed in the supply port side region A1. Specifically, the number of the first through-holes 23a is preferably less than the number of the second through-holes 23b in the supply port side region A1 and more than the number of the second through-holes 23b in the discharge port side region A2. That is, the ratio of the first through-holes 23a to the second through-holes 23b in the supply port side region A1 is preferably smaller than the ratio of the first through-holes 23a to the second through-holes 23b in the discharge port side region A2.

[0084] (i) In the electrolytic cell 100 of the above embodiment, more first through-holes 23a than second through-holes 23b are formed in the supply port side region A1, and more second through-holes 23b than first through-holes 23a are formed in the discharge port side region A2. However, the configuration of the electrolytic cell 100 is not limited thereto. For example, in the supply port side region A1, the number of the second through-holes 23b may be more than that of the first through-holes 23a, or in the discharge port side region A2, the number of the first through-holes 23a may be more than that of the second through-holes 23b.

Explanation of reference numerals

[0085] 2: Metal plate 21: First main surface 22: Second main surface 23: Through-hole 23a: First through-hole 23b: Second through-hole 3: Cell main body portion 31: Hydrogen electrode layer 32: Electrolyte layer 34: Oxygen electrode layer 4: First oxide protrusion 5: First non-oxide protrusion 7: Second oxide protrusion 8: Second non-oxide protrusion 61: Flow path 100: Electrolytic cell A1: Supply port side region A2: Discharge port side region

Claims

1. a metal plate having a first main surface, a second main surface, a first through hole, and a second through hole; a cell main body portion having a first electrode layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer, the cell main body portion being disposed on the first main surface of the metal plate; a first oxide protrusion that is made of an oxide and that is disposed on an inner wall surface of the first through hole; a first non-oxide protrusion disposed on an inner wall surface of the second through hole, the first non-oxide protrusion being configured to have a surface covered with a non-oxide; Equipped with At least one of the first oxide protrusion and the first non-oxide protrusion is annular and extends circumferentially on the inner wall surface. Electrochemical cell.

2. At least one of the first oxide protrusions and the first non-oxide protrusions is made of a material having a higher Young's modulus than the metal plate.

10. The electrochemical cell of claim 1.

3. At least one of the first oxide protrusion and the first non-oxide protrusion is disposed on an end of the inner wall surface on the second main surface side.

10. The electrochemical cell of claim 1.

4. a second oxide protrusion made of a material containing an oxide and disposed on an inner wall surface of the first through hole closer to the first main surface than the first oxide protrusion; 10. The electrochemical cell of claim 1.

5. a second non-oxide protrusion made of a material containing a non-oxide and disposed on an inner wall surface of the second through hole closer to the first main surface than the first non-oxide protrusion; 10. The electrochemical cell of claim 1.

6. a second oxide protrusion made of a material containing an oxide and disposed on an inner wall surface of the second through hole closer to the first main surface than the first non-oxide protrusion; 10. The electrochemical cell of claim 1.

7. a second non-oxide protrusion made of a material containing a non-oxide and disposed on an inner wall surface of the first through hole closer to the first main surface than the first oxide protrusion; 10. The electrochemical cell of claim 1.

8. the first oxide protrusion is made of a material including ceramics; 10. The electrochemical cell of claim 1.

9. the first non-oxide protrusion is made of a material containing a metal; 10. The electrochemical cell of claim 1.

10. a plurality of the first through holes in which the first oxide protrusions are formed; a plurality of the second through holes in which the first non-oxide protrusions are formed; Equipped with the metal plate has a supply port side region arranged on a supply port side of a flow path for a source gas supplied to the cell main body portion through the first through hole and the second through hole, and an exhaust port side region arranged on an exhaust port side of the flow path, a ratio of the first through holes to the second through holes is larger in the supply port side region than in the discharge port side region; 10. The electrochemical cell of claim 1.

11. a plurality of the first through holes in which the first oxide protrusions are formed; a plurality of the second through holes in which the first non-oxide protrusions are formed; Equipped with the metal plate has a supply port side region arranged on a supply port side of a flow path for a source gas supplied to the cell main body portion through the first through hole and the second through hole, and an exhaust port side region arranged on an exhaust port side of the flow path, a ratio of the first through holes to the second through holes is smaller in the supply port side region than in the discharge port side region; 10. The electrochemical cell of claim 1.

12. a metal plate having a first main surface, a second main surface, a first through hole, and a second through hole; a cell main body portion having a first electrode layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer, the cell main body portion being disposed on the first main surface of the metal plate; a first oxide protrusion that is made of an oxide and that is disposed on an inner wall surface of the first through hole; a first non-oxide protrusion disposed on an inner wall surface of the second through hole, the first non-oxide protrusion being configured to have a surface covered with a non-oxide; Equipped with At least one of the first oxide protrusions and the first non-oxide protrusions is made of a material having a higher Young's modulus than the metal plate. Electrochemical cell.

13. a metal plate having a first main surface, a second main surface, a plurality of first through holes, and a plurality of second through holes; a cell main body portion having a first electrode layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer, the cell main body portion being disposed on the first main surface of the metal plate; a first oxide protrusion that is made of an oxide and that is disposed on an inner wall surface of the first through hole; a first non-oxide protrusion disposed on an inner wall surface of the second through hole, the first non-oxide protrusion being configured to have a surface covered with a non-oxide; Equipped with the metal plate has a supply port side region arranged on a supply port side of a flow path for a source gas supplied to the cell main body portion through the first through hole and the second through hole, and an exhaust port side region arranged on an exhaust port side of the flow path, a ratio of the first through holes to the second through holes is larger in the supply port side region than in the discharge port side region; Electrochemical cell.

14. a metal plate having a first main surface, a second main surface, a plurality of first through holes, and a plurality of second through holes; a cell main body portion having a first electrode layer, a second electrode layer, and an electrolyte layer disposed between the first electrode layer and the second electrode layer, the cell main body portion being disposed on the first main surface of the metal plate; a first oxide protrusion that is made of an oxide and that is disposed on an inner wall surface of the first through hole; a first non-oxide protrusion disposed on an inner wall surface of the second through hole, the first non-oxide protrusion being configured to have a surface covered with a non-oxide; Equipped with the metal plate has a supply port side region arranged on a supply port side of a flow path for a source gas supplied to the cell main body portion through the first through hole and the second through hole, and an exhaust port side region arranged on an exhaust port side of the flow path, a ratio of the first through holes to the second through holes is smaller in the supply port side region than in the discharge port side region; Electrochemical cell.

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