Metal support for electrochemical element, electrochemical element, electrochemical module, electrochemical device, energy system, solid oxide fuel cell, solid oxide electrolytic cell, and method for manufacturing metal support

Abstract

To provide an electrochemical element or the like improved in workability and cost in mass production while securing sufficient strength and performance.SOLUTION: The metallic support 1 of the electrochemical device has a plurality of penetration space side walls penetrating from a front side 1a to a rear side 1a, the front side 1b being a 1c on which electrodes are provided. The honeycomb structure has one or more hole regions 1a as regions where the penetration space 1c is formed in the front side surface 1g, and the average circularity of the opening 1g of the front side surface 1c of the penetration space 1a in at least one or more hole regions 1d is 0.80 or less.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a metal-supported electrochemical element and a metal support therefor. [Background technology]

[0002] In conventional metal-supported electrochemical devices, the metal support is made of a metal plate with many holes drilled in it, but the optimal hole shape that ensures sufficient performance as an electrochemical device while also taking into account processability and cost during mass production has not yet been found. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 189912 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 discloses a metal support structure that takes into consideration processability during element stacking. In the element of Patent Document 1, an electrode layer, an electrolyte layer, and a counter electrode layer are stacked on a metal plate with many holes. In metal-supported electrochemical elements, the electrodes sink into the holes when forming the electrodes on the surface of the metal support, making it difficult to form the electrochemical element. In addition, defects on the electrode surface caused by the sinking reduce the strength of the metal-supported electrochemical element.

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an electrochemical element or the like that makes it easy to form an electrode layer on the surface of a metal support and that can increase the strength. [Means for solving the problem]

[0006] A characteristic configuration of the metal support for an electrochemical element for achieving the above-mentioned object is that the metal support has a front side on which an electrode layer is provided, a plurality of through spaces penetrating from the front side to the back side, and has one or more hole regions as regions in which the through spaces are formed on the front side, and the average circularity of the openings of the through spaces on the front side in at least one of the hole regions is 0.80 or less.

[0007] According to the above-described characteristic configuration, the average circularity of the openings on the front side surface in the hole region is 0.80 or less, which increases the perimeter per area of ​​the openings. This reduces the likelihood of the electrode layer sinking into the holes that form the through-space, facilitating the formation of the electrode layer on the metal support and enhancing the strength of the electrochemical element. Furthermore, the complex shape of the hole wall surface facilitates turbulence within the through-space, enhancing material diffusion and improving the generated voltage of the electrochemical element. If the average circularity exceeds 0.80, the turbulence within the through-space is suppressed, reducing material diffusion and lowering the generated voltage of the electrochemical element. Note that circularity is a numerical value that indicates how close the shape of the openings is to a circle, with a perfect circle being 1. Furthermore, the average circularity is calculated by selecting any one hole region from the front side surface, calculating the circularity of each of the openings formed within that region, and averaging the calculated values.

[0008] A characteristic feature of the metal support for an electrochemical element for achieving the above object is that the hole region has at least one opening on the front side surface, the opening having an area coverage ratio of 0.88 to 0.98.

[0009] The area envelopment ratio is an index that represents the degree of unevenness of the opening. The smoother the opening, the closer the area envelopment ratio is to 1. If the area envelopment ratio is less than 0.88, oxidation of the inner wall of the through-space progresses, resulting in a thick oxide film, which narrows the through-space and reduces substance diffusion. According to the above-mentioned characteristic configuration, having at least one opening with an area envelopment ratio of 0.88 to 0.98 promotes the supply of materials necessary for the electrochemical reaction and the discharge of materials produced by the electrochemical reaction, thereby improving, for example, the power generation voltage of the electrochemical element. Furthermore, if the area envelopment ratio is 0.98 or less, the perimeter per area of ​​the opening is long, making it difficult for the electrode layer to sink into the holes that form the through-space. This makes it easier to form the electrode layer on the metal support and increases the strength of the electrochemical element.

[0010] A characteristic feature of the metal support for an electrochemical element for achieving the above object is that the metal support has at least one opening in the hole region on the front side surface, the opening having a perimeter envelopment ratio of 0.57 to 0.99.

[0011] The perimeter envelope is an index that represents the degree of irregularity of the opening. The smoother the opening, the closer the perimeter envelope is to 1. If the perimeter envelope is less than 0.57, oxidation of the inner wall of the through-hole progresses, resulting in a thick oxide film, which narrows the through-hole and reduces substance diffusion. According to the above-described characteristic configuration, having at least one opening with a perimeter envelope of 0.57 or more and 0.99 or less promotes the supply of materials necessary for the electrochemical reaction and the discharge of materials produced by the electrochemical reaction, thereby improving, for example, the power generation voltage of an electrochemical element. Furthermore, if the perimeter envelope is 0.99 or less, the perimeter per area of ​​the opening is long, making it difficult for the electrode layer to sink into the holes that form the through-hole. This facilitates the formation of the electrode layer on the metal support and increases the strength of the electrochemical element.

[0012] Another characteristic feature of the metal support according to the present invention is that the opening ratio, which is the ratio of the openings in the front side surface to the hole region, is 0.1% or more and 7.0% or less.

[0013] According to the above-described characteristic configuration, the aperture ratio is 0.1% or more. Therefore, when this metal support is used, a sufficient amount of fuel gas (or air) can be supplied to the electrode layer of the electrochemical device, thereby ensuring sufficient performance as an electrochemical device. An aperture ratio of 0.15% or more is more preferable, and an aperture ratio of 0.7% or more is even more preferable. In this way, the larger the aperture ratio, the more fuel gas (or air) can be supplied to the electrode layer of the electrochemical device, thereby further improving the performance of the electrochemical device. Furthermore, since the aperture ratio is 7.0% or less, the strength of the metal support is sufficiently maintained, resulting in a highly reliable electrochemical device. Furthermore, the cost of processing the through-holes can be reduced. Furthermore, it is preferable that the components of the electrochemical device, such as the electrode layer, can be easily formed on the metal support having a plurality of through-holes. An aperture ratio of 6.0% or less is more preferable, and an aperture ratio of 5.5% or less is even more preferable. This configuration further enhances the aforementioned effects.

[0014] In the metal support according to the present invention, the spacing between the openings on the front side surface may be 0.05 mm or more and 0.3 mm or less.

[0015] The above characteristic configuration is advantageous in that it achieves both strength and performance of the metal support. The spacing between the front-side openings is preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.15 mm or more. This not only increases the strength of the metal support but also makes it easier to form components of an electrochemical device, such as an electrode layer, on a metal support having multiple through-holes. The spacing between the front-side openings is preferably 0.3 mm or less, more preferably 0.25 mm or less, and even more preferably 0.2 mm or less. This reduces the likelihood of the electrodes sinking into the holes, facilitating the formation of an electrode layer on the metal support and increasing the strength of the electrochemical device. Furthermore, it becomes possible to supply a sufficient amount of fuel gas (or air) to the electrode layer of the electrochemical device, thereby further improving the performance of the electrochemical device.

[0016] The metal support according to the present invention has an area of ​​the hole region of 9 cm 2 It would be better if it was more than that.

[0017] According to the above characteristic configuration, the area of ​​the hole region is 9 cm 2 Use of the above metal support is preferable because it allows a sufficient amount of fuel gas (or air) to be supplied to the electrode layer of the electrochemical element, ensuring sufficient performance as an electrochemical element.

[0018] The metal support according to the present invention preferably has a thickness of 0.1 mm or more and 1.0 mm or less.

[0019] According to the above characteristic configuration, the size of the through-hole can be appropriately set while maintaining sufficient overall strength of the metal support, which is advantageous because it improves processability during mass production and reduces material costs. The thickness of the metal support is preferably 0.1 mm or more, more preferably 0.15 mm or more, and even more preferably 0.2 mm or more. This makes it easier to handle during mass production while maintaining the strength of the metal support. The thickness of the metal support is preferably 1.0 mm or less, more preferably 0.75 mm or less, and even more preferably 0.5 mm or less. This makes it possible to further reduce material costs for the metal support while maintaining the strength of the metal support.

[0020] Another characteristic feature of the metal support according to the present invention is that it is formed by stacking a plurality of metal plates.

[0021] According to the above characteristic configuration, the size of the through space can be made appropriate while ensuring the overall thickness of the metal support body and maintaining sufficient strength, which is advantageous in that it improves processability during mass production.

[0022] According to the above characteristic configuration, the size of the through-hole can be appropriately set while ensuring the overall thickness of the metal support and maintaining sufficient strength, which is preferable because it improves processability during mass production.In this case, the size of the openings formed in the thinner first metal plate can be made smaller than the size of the openings formed in the thicker second metal plate, and they can be overlapped and joined to form a metal support with a sufficient overall thickness.This makes it possible to increase the ratio of the overall thickness of the metal support to the area of ​​the front-side openings of the metal support, which is preferable because it makes it easier to form components of an electrochemical device, such as electrode layers, on the metal support while maintaining sufficient strength.

[0023] Another characteristic feature of the metal support according to the present invention is that the material is an Fe-Cr alloy.

[0024] The above-described characteristic configuration improves the oxidation resistance and high-temperature strength of the metal support. In addition, the thermal expansion coefficient can be made close to that of the materials of the components of the electrochemical device, such as the electrode layer and electrolyte layer, formed on the metal support, which is preferable because it allows the realization of an electrochemical device with excellent heat cycle durability.

[0025] Another characteristic feature of the metal support according to the present invention is that at least a part of the front side surface is covered with a metal oxide film.

[0026] According to the above characteristic configuration, the metal oxide coating can prevent components such as Cr from diffusing from the metal support to the electrode layer, etc., thereby preventing performance degradation of the electrode layer, etc., and improving the performance and durability of the electrochemical element.

[0027] An electrochemical element having at least an electrode layer, an electrolyte layer, and a counter electrode layer provided on the front surface of the metal support as described above is preferable because it ensures sufficient performance while improving the workability and cost in mass production. Furthermore, since the components of the electrochemical element, such as the electrode layer and the electrolyte layer, are formed on the metal support having excellent strength, it is possible to make the components of the electrochemical element, such as the electrode layer and the electrolyte layer, thinner, which makes it possible to reduce the material cost of the electrochemical element.

[0028] The electrochemical module according to the present invention is characterized in that a plurality of the above-described electrochemical elements are arranged in a group.

[0029] According to the above characteristic configuration, a plurality of the above-mentioned electrochemical elements are arranged in a cluster, so that a compact, high-performance electrochemical module with excellent strength and reliability can be obtained while reducing material costs and processing costs.

[0030] The electrochemical device according to the present invention is characterized in that it has at least the electrochemical module and fuel converter described above, and has a fuel supply unit that supplies reducing component gas from the fuel converter to the electrochemical element or the electrochemical module, or that supplies reducing component gas from the electrochemical element or the electrochemical module to the fuel converter.

[0031] According to the above characteristic configuration, an electrochemical device includes an electrochemical module, a fuel converter, and a fuel supply unit that circulates a gas containing a reducing component between the electrochemical module and the fuel converter. Therefore, when the electrochemical module is operated as a fuel cell, if hydrogen is generated using a fuel converter such as a reformer from natural gas or the like supplied using an existing raw fuel supply infrastructure such as city gas, an electrochemical device equipped with an electrochemical element or electrochemical module that is excellent in durability, reliability, and performance can be realized. Furthermore, since it becomes easy to build a system that recycles unused fuel gas circulated from the electrochemical module, a highly efficient electrochemical device can be realized. When the electrochemical module is operated as an electrolysis cell, gas containing water vapor and carbon dioxide is passed through the electrode layer, and a voltage is applied between the electrode layer and the counter electrode layer. Then, electrons e - reacts with water molecules H2O and carbon dioxide molecules CO2, producing hydrogen molecules H2, carbon monoxide CO, and oxygen ions O 2- Oxygen ions O 2- moves through the electrolyte layer to the counter electrode layer. In the counter electrode layer, oxygen ions O 2-releases electrons and becomes oxygen molecules O2. Through the above reaction, water molecules H2O are decomposed into hydrogen H2 and oxygen O2, and when gas containing carbon dioxide molecules CO2 is circulated, it is electrolyzed into carbon monoxide CO and oxygen O2. When gas containing water vapor and carbon dioxide molecules (CO2) is circulated, a fuel converter can be provided that synthesizes various compounds such as hydrocarbons from the hydrogen and carbon monoxide produced in the electrochemical module by the electrolysis. The hydrocarbons produced by this fuel converter can be circulated to the electrochemical module by a fuel supply unit, or extracted from this system / device and used separately as fuel or chemical raw materials.

[0032] The electrochemical device according to the present invention is characterized by having at least the above-mentioned electrochemical module and a power converter that extracts electric power from the electrochemical module or passes electric power to the electrochemical module.

[0033] According to the above characteristic configuration, the power converter extracts power generated by the electrochemical module or distributes power to the electrochemical module. As a result, the electrochemical module functions as a fuel cell or an electrolysis cell. Therefore, according to the above configuration, it is possible to provide an electrochemical device or the like that can improve the efficiency of converting chemical energy such as fuel into electrical energy or converting electrical energy into chemical energy such as fuel. For example, when an inverter is used as a power converter, the inverter can boost the electrical output obtained from the electrochemical module, which has excellent durability, reliability, and performance, or convert direct current to alternating current, making it easier to utilize the electrical output obtained from the electrochemical module, which is preferable.

[0034] The energy system according to the present invention is characterized by having the electrochemical device described above and a waste heat utilization section that reuses heat discharged from the electrochemical device.

[0035] According to the above characteristic configuration, since the electrochemical device and the waste heat utilization unit that reuses the heat discharged from the electrochemical device are included, an energy system that is excellent in durability, reliability, and performance, as well as energy efficiency, can be realized. Furthermore, it is also possible to realize a hybrid system with excellent energy efficiency by combining it with a power generation system that generates electricity by utilizing the combustion heat of unused fuel gas discharged from the electrochemical device.

[0036] The solid oxide fuel cell according to the present invention is characterized by comprising the electrochemical element described above, and causing a power generation reaction.

[0037] According to the above-described characteristic configuration, a power generation reaction can be performed in a solid oxide fuel cell equipped with an electrochemical element that is durable, reliable, and highly functional, thereby achieving a highly durable and high-performance solid oxide fuel cell. Furthermore, a solid oxide fuel cell that can operate at a temperature range of 650°C or higher during rated operation is preferable because it can be used in a fuel cell system that uses hydrocarbon gases such as city gas as raw fuel, where the heat required to convert the raw fuel into hydrogen can be supplied by the exhaust heat of the fuel cell, thereby improving the power generation efficiency of the fuel cell system. Furthermore, a solid oxide fuel cell that operates at a temperature range of 900°C or lower during rated operation is more preferable because it can effectively suppress Cr volatilization from the metal-supported electrochemical element. A solid oxide fuel cell that operates at a temperature range of 850°C or lower during rated operation is even more preferable because it can further enhance the suppression of Cr volatilization.

[0038] The solid oxide electrolysis cell according to the present invention is characterized by including the above-described electrochemical element and causing an electrolytic reaction.

[0039] According to the above characteristic configuration, a solid oxide electrolysis cell having an electrochemical element with excellent durability, reliability, and performance can be used to generate gas through an electrolytic reaction, and therefore a highly durable and high-performance solid oxide electrolysis cell can be obtained.

[0040] To achieve the above object, the manufacturing method for manufacturing the above-mentioned metal support is characterized in that a plurality of through spaces that penetrate from the front side to the back side are formed by laser processing, punching processing, etching processing, or a combination thereof.

[0041] According to the above characteristic configuration, the through-space can be easily formed, and the workability and cost in mass production can be improved. [Brief explanation of the drawings]

[0042] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of an electrochemical element. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of an electrochemical element and an electrochemical module. [Figure 3] FIG. 1 is a schematic diagram showing the configuration of an electrochemical device and an energy system. [Figure 4] FIG. 2 is a schematic diagram showing the configuration of an electrochemical module. [Figure 5] 2A and 2B are a plan view and a cross-sectional view showing the structure of a metal support; [Figure 6] 2A and 2B are a plan view and a cross-sectional view showing the structure of a metal support; [Figure 7] FIG. 1 is a schematic diagram showing the configuration of another electrochemical device and energy system. DETAILED DESCRIPTION OF THE INVENTION

[0043] First Embodiment An electrochemical element E and a solid oxide fuel cell (SOFC) according to this embodiment will be described below with reference to FIG. 1. The electrochemical element E is used, for example, as a component of a solid oxide fuel cell that generates electricity when supplied with a fuel gas containing hydrogen and air. Hereinafter, when describing the positional relationship between layers, the side of the counter electrode layer 6 as viewed from the electrolyte layer 4 may be referred to as "top" or "upper side," and the side of the electrode layer 2 as "bottom" or "lower side." The surface of the metal support 1 on which the electrode layer 2 is formed is referred to as the front side 1a, and the opposite surface is referred to as the back side 1b.

[0044] (electrochemical element) 1, the electrochemical element E has a metal support 1, an electrode layer 2 formed on the metal support 1, an intermediate layer 3 formed on the electrode layer 2, and an electrolyte layer 4 formed on the intermediate layer 3. The electrochemical element E further has a reaction prevention layer 5 formed on the electrolyte layer 4, and a counter electrode layer 6 formed on the reaction prevention layer 5. In other words, the counter electrode layer 6 is formed on the electrolyte layer 4, and the reaction prevention layer 5 is formed between the electrolyte layer 4 and the counter electrode layer 6. The electrode layer 2 is porous, and the electrolyte layer 4 is dense.

[0045] (metal support) The metal support 1 supports the electrode layer 2, the intermediate layer 3, the electrolyte layer 4, etc., and maintains the strength of the electrochemical element E. In other words, the metal support 1 serves as a support for supporting the electrochemical element E.

[0046] The metal support 1 is made of a material with excellent electronic conductivity, heat resistance, oxidation resistance, and corrosion resistance. Examples include ferritic stainless steel, austenitic stainless steel, and nickel-based alloys. In particular, alloys containing chromium are preferred. In this embodiment, the metal support 1 is made of an Fe—Cr alloy containing 18 to 25% by mass of Cr. However, particularly preferred are an Fe—Cr alloy containing 0.05% by mass or more of Mn, an Fe—Cr alloy containing 0.15 to 1.0% by mass of Ti, an Fe—Cr alloy containing 0.15 to 1.0% by mass of Zr, an Fe—Cr alloy containing Ti and Zr with a total content of Ti and Zr of 0.15 to 1.0% by mass, and an Fe—Cr alloy containing 0.10 to 1.0% by mass of Cu.

[0047] The metal support 1 is generally plate-shaped. The surface of the metal support 1 on which the electrode layer 2 is provided is the front side surface 1a, and the metal support 1 has a plurality of through-spaces 1c penetrating from the front side surface 1a to the back side surface 1b. The through-spaces 1c have the function of allowing gas to pass from the back side surface 1b of the metal support 1 to the front side surface 1a. The plate-shaped metal support 1 can also be bent and deformed into a shape such as a box or a cylinder for use.

[0048] A metal oxide layer 1f (metal oxide film) is provided on the surface of the metal support 1 as a diffusion-inhibiting layer. That is, the diffusion-inhibiting layer is formed between the metal support 1 and the electrode layer 2 described later. The metal oxide layer 1f is provided not only on the surface of the metal support 1 exposed to the outside but also on the contact surface (interface) with the electrode layer 2. It can also be provided on the inner surface of the through-space 1c. This metal oxide layer 1f can inhibit interdiffusion of elements between the metal support 1 and the electrode layer 2. For example, when ferritic stainless steel containing chromium is used as the metal support 1, the metal oxide layer 1f is mainly composed of chromium oxide. The metal oxide layer 1f, which is mainly composed of chromium oxide, inhibits the diffusion of chromium atoms and the like from the metal support 1 into the electrode layer 2 and the electrolyte layer 4. The thickness of the metal oxide layer 1f may be any thickness that achieves both high diffusion prevention performance and low electrical resistance. The metal oxide layer 1f can be formed by various methods, but a method of oxidizing the surface of the metal support 1 to form a metal oxide is preferably used. The metal oxide layer 1f may be formed on the surface of the metal support 1 by a spray coating method (such as a thermal spraying method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method such as a sputtering method or a PLD method, or a CVD method, or may be formed by plating and oxidation treatment. Furthermore, the metal oxide layer 1f may contain a highly conductive spinel phase or the like.

[0049] When a ferritic stainless steel material is used as the metal support 1, its thermal expansion coefficient is close to that of YSZ (yttria-stabilized zirconia) or GDC (gadolinium-doped ceria, also known as CGO), which are used as materials for the electrode layer 2 and the electrolyte layer 4. Therefore, the electrochemical element E is less likely to be damaged even when subjected to repeated temperature cycles of low and high temperatures. This is preferable because it allows for the realization of an electrochemical element E with excellent long-term durability.

[0050] (Metal support and through-space structure) In the example of FIG. 1, the metal support 1 is composed of a single metal plate. The metal support 1 can also be formed by stacking multiple metal plates. The metal support 1 can also be formed by stacking multiple metal plates of the same or approximately the same thickness. The metal support 1 can also be formed by stacking multiple metal plates of different thicknesses. Below, examples of the structure of the metal support 1 and the through-space 1c will be described with reference to the drawings. Note that the metal oxide layer 1f is not shown in the illustration.

[0051] <Example 1> Referring to FIG. 5, an example (first example) in which the metal support 1 is formed from a single metal plate will be described. As shown in FIG. 5, the metal support 1 is a plate-like member with a thickness T, i.e., it is plate-like as a whole. The metal support 1 has multiple through-spaces 1c penetrating from the front side surface 1a to the back side surface 1b. In the first example, the through-spaces 1c are holes with circular cross sections. The cross-sectional shape of the through-spaces 1c can be circular or approximately circular, as well as rectangular, triangular, or polygonal. As long as the through-spaces 1c can be formed, various shapes can be used as long as the functionality of the metal support 1 is maintained. These holes (through-spaces 1c) can be formed by changing the laser irradiation position or the shape of a punching die according to the shape. The through-spaces 1c can be formed in the metal support 1 by laser processing, punching, etching, or a combination thereof. The central axis of the holes is perpendicular to the metal support 1. The central axis of the holes (through-spaces 1c) may be inclined relative to the metal support 1.

[0052] The opening on the front surface 1a of the through space 1c is called the front opening 1d. The opening on the back surface 1b of the through space 1c is called the back opening 1e. Because the cross section of the through space 1c is a circular hole, the front opening 1d and the back opening 1e are both circular. The front opening 1d and the back opening 1e may be the same size. The back opening 1e may be larger than the front opening 1d. The diameter of the front opening 1d is called diameter D.

[0053] 5, a plurality of holes (through spaces 1c) are formed at the positions of lattice points of an orthogonal lattice at a pitch (spacing) P in the metal support 1. The arrangement of the plurality of holes (through spaces 1c) can be an orthogonal lattice, an oblique lattice, or an equilateral triangular lattice, and they can be arranged at diagonal intersections in addition to lattice points. As long as the through spaces can be formed, various arrangements are possible as long as the function of the metal support is maintained.

[0054] The region on the front side surface 1a of the metal support 1 where the through-space 1c is formed is called the hole region 1g. The hole region 1g is provided within a range excluding the periphery of the outer periphery of the metal support 1. One hole region 1g may be provided in the metal support 1, or multiple hole regions 1g may be provided in the metal support 1. The area of ​​one hole region 1g is 9 cm 2 More than 36cm is preferable. 2 More than 81cm is preferable. 2 The above is more preferable.

[0055] The metal support 1 is required to have sufficient strength to serve as a support for forming the electrochemical element E. The thickness T of the metal support 1 is preferably 0.1 mm or more, more preferably 0.15 mm or more, and even more preferably 0.2 mm or more. The thickness T of the metal support 1 is preferably 1.0 mm or less, more preferably 0.75 mm or less, and even more preferably 0.5 mm or less.

[0056] The diameter D of the front opening 1d is preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 20 μm or more. The diameter D of the front opening 1d is preferably 60 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less.

[0057] This facilitates the processing and formation of the through-spaces, which is advantageous in that it improves the processability and cost during mass production. The front-side opening is preferably circular or approximately circular with a diameter of 10 μm or more, more preferably circular or approximately circular with a diameter of 15 μm or more, and even more preferably circular or approximately circular with a diameter of 20 μm or more. This allows a sufficient amount of fuel gas (or air) to be supplied to the electrode layer of the electrochemical device, further improving the performance of the electrochemical device. The front-side opening is preferably circular or approximately circular with a diameter of 60 μm or less, more preferably circular or approximately circular with a diameter of 50 μm or less, and even more preferably circular or approximately circular with a diameter of 40 μm or less. This improves the strength of the metal support, while making it easier to form components of the electrochemical device, such as electrode layers, on a metal support having a plurality of through-spaces.

[0058] The pitch P of the arrangement of the through spaces 1c (holes) is preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.15 mm or more. The pitch P of the arrangement of the through spaces 1c (holes) is preferably 0.3 mm or less, more preferably 0.25 mm or less, and even more preferably 0.2 mm or less.

[0059] The area S of the front opening 1d of the through space 1c is 7.0 × 10 -5 mm 2 It is preferable that it is 3.0 × 10 or more. -3 mm 2 It is preferable that the following is true:

[0060] The areas where the through-spaces 1c formed in the metal support 1 existed and the areas where the through-spaces 1c did not exist were distinguished by binarization processing using a microscope VHX-8000 (manufactured by Keyence Corporation). A threshold value was set and the value of each pixel was compared; if it was greater than the threshold, it was converted to white; if it was less than the threshold, it was converted to black. For example, areas where the through-spaces 1c existed were converted to black because their pixel values ​​were low, and areas where the through-spaces 1c did not exist were converted to white because their pixel values ​​were high. After simplifying the image through binarization processing, the following measurements were performed. The threshold value was arbitrarily set to an optimal value for each image.

[0061] The circularity of the front-side opening 1d was measured using a microscope VHX-8000 (manufactured by Keyence Corporation). Circularity indicates how close the front-side opening 1d is to a perfect circle. The closer the shape of the front-side opening 1d is to a perfect circle, the closer the circularity is to 1. The circularity can be calculated using Equation 1 using the area S and perimeter L of the front-side opening 1d. Six regions were randomly selected from the multiple hole regions 1g provided in the metal support 1, and the circularity of 40 holes was measured to calculate the average circularity. In this embodiment, the circularity of the front-side opening 1d is preferably 0.20 or more, more preferably 0.30 or more, and even more preferably 0.40 or more. The circularity of the front-side opening 1d is preferably 0.80 or less, more preferably 0.70 or less, and even more preferably 0.60 or less.

[0062]

number

[0063] The area envelopment and perimeter envelopment of the front opening 1d were measured using a microscope VHX-8000 (manufactured by Keyence Corporation). The area envelopment and perimeter envelopment represent the degree of irregularity of the front opening 1d. The smoother the contour of the front opening 1d, the closer the area envelopment and perimeter envelopment values ​​are to 1. The area envelopment can be calculated using Equation 2, and the perimeter envelopment can be calculated using Equation 3. The envelope perimeter in Equations 2 and 3 is defined as the length of a rubber band when it is assumed to be wrapped around the front opening 1d. In this embodiment, the area envelopment of the front opening 1d is preferably 0.60 or more, more preferably 0.70 or more, and even more preferably 0.80 or more. The area envelopment of the front opening 1d is preferably 0.98 or less, more preferably 0.95 or less, and even more preferably 0.90 or less. The perimeter envelope of the front opening 1d is preferably 0.57 or more, more preferably 0.70 or more, and even more preferably 0.80 or more. The perimeter envelope of the front opening 1d is preferably 0.99 or less, more preferably 0.90 or less, and even more preferably 0.85 or less.

[0064]

number

[0065]

number

[0066] The proportion of the front openings 1d in the hole region 1g is defined as the opening ratio A. The opening ratio A is preferably 0.1% or more, more preferably 0.15% or more, and even more preferably 0.7% or more. The opening ratio A is preferably 7.0% or less, more preferably 6.0% or less, and even more preferably 5.5% or less. The opening ratio A is calculated by dividing the total area S of the front openings 1d in the hole region 1g by the area of ​​the hole region 1g.

[0067] The aperture ratio A can also be calculated by focusing on the regions that appear periodically in the hole region 1g. For example, focusing on the unit region 1h shown in Figure 5, the value obtained by dividing the area S by the area of ​​the unit region 1h (the square of the pitch P) is approximately equal to the aperture ratio A of the entire hole region 1g. That is, in the case of the orthogonal lattice shown in Figure 5, the aperture ratio A can be calculated using the following formula 4. When the front-side opening 1d is a circle with a diameter D, the relationship of the following formula 5 also holds.

[0068]

number

[0069]

number

[0070] <Example 2> Referring to FIG. 6, an example (second example) in which the metal support 1 is formed by stacking multiple metal plates of the same thickness will be described. As shown in FIG. 6, in the second example, the metal support 1 is composed of a first metal plate 10 having a thickness T1 and a second metal plate 20 having a thickness T2. The first metal plate 10 and the second metal plate 20 have the same thickness. The metal support 1 is formed by stacking the first metal plate 10 and the second metal plate 20. The metal support 1 is a plate-shaped member having an overall thickness T. The first metal plate 10 and the second metal plate 20 are joined by a technique such as spot welding, brazing, or vacuum joining. The first metal plate 10 and the second metal plate 20 may have slightly different thicknesses, i.e., may have approximately the same thickness.

[0071] The first metal plate 10 has a plurality of first through spaces 10c penetrating from the first front side surface 10a, which is the front surface, to the first back side surface 10b, which is the back surface. The first through spaces 10c are holes with a circular cross section. The cross-sectional shape of the first through spaces 10c can be circular, approximately circular, rectangular, triangular, polygonal, or other shapes. These holes (first through spaces 10c) can be formed by changing the laser irradiation position or the shape of the punching die according to the shape. In addition to laser processing and punching, the first metal plate 10 can be formed by etching, laser processing, punching, or etching, or a combination of these. The central axis of these holes is perpendicular to the first metal plate 10. The central axis of the holes (first through spaces 10c) may be inclined relative to the first metal plate 10.

[0072] The opening of the first through space 10c in the first front side surface 10a is referred to as the first front opening 10d. The opening of the first through space 10c in the first back side surface 10b is referred to as the first back opening 10e. Because the cross section of the first through space 10c is a circular hole, the first front opening 10d and the first back opening 10e are both circular. The first front opening 10d and the first back opening 10e may be the same size. The first back opening 10e may be larger than the first front opening 10d. The diameter of the first front opening 10d is referred to as diameter D1.

[0073] 6, a plurality of holes (first through spaces 10c) are formed at the positions of lattice points of an orthogonal lattice at a pitch P1 (spacing) in the first metal plate 10. The arrangement of the plurality of holes (first through spaces 10c) can be an orthogonal lattice, an oblique lattice, or an equilateral triangular lattice, and they can be arranged at diagonal intersections in addition to lattice points.

[0074] The second metal plate 20 has a plurality of second through-spaces 20c penetrating from the second front side surface 20a, which is the front surface, to the second back side surface 20b, which is the back surface. The second through-spaces 20c are holes with a circular cross-section. The cross-sectional shape of the second through-spaces 20c can be circular, approximately circular, rectangular, triangular, polygonal, or other shapes. These holes (second through-spaces 20c) can be formed by changing the laser irradiation position or the punching die shape according to the shape. They are formed in the second metal plate 20 by laser processing, punching processing, etching processing, or a combination thereof. The central axis of these holes is perpendicular to the second metal plate 20. The central axis of the holes (second through-spaces 20c) may be inclined relative to the second metal plate 20. As a second example, an example is shown in which the diameter of the second through-spaces 20c in the second metal plate 20 is equal to the diameter of the first through-spaces 10c in the first metal plate 10. The diameter of the first through space 10c and the diameter of the second through space 20c may be different.

[0075] The opening of the second through space 20c in the second front side surface 20a is referred to as the second front opening 20d. The opening of the second through space 20c in the second back side surface 20b is referred to as the second back opening 20e. Because the cross section of the second through space 20c is a circular hole, the second front opening 20d and the second back opening 20e are both circular. The second front opening 20d and the second back opening 20e may be the same size. The second back opening 20e may be larger than the second front opening 20d. The diameter of the second front opening 20d is referred to as diameter D2.

[0076] In the second example, the diameter of the second through space 20c of the second metal plate 20 is equal to the diameter of the first through space 10c of the first metal plate 10. Therefore, the diameter D1 of the first front-side opening 10d is equal to the diameter D2 of the second front-side opening 20d.

[0077] 6, a plurality of holes (second through spaces 20c) are formed at the positions of lattice points of an orthogonal lattice at a pitch P2 (spacing) in the second metal plate 20. The arrangement of the plurality of holes (second through spaces 20c) can be an orthogonal lattice, an oblique lattice, or an equilateral triangular lattice, and they can be arranged at diagonal intersections in addition to lattice points.

[0078] In the second example, the pitch P2 of the second through spaces 20c of the second metal plate 20 is equal to the pitch P1 of the first through spaces 10c of the first metal plate 10. The first metal plate 10 and the second metal plate 20 are joined together in an overlapping manner so that the second through spaces 20c of the second metal plate 20 and the first through spaces 10c of the first metal plate 10 overlap in a top view. Therefore, the first through spaces 10c and the second through spaces 20c communicate with each other. The first through spaces 10c and the second through spaces 20c communicate with each other to form through spaces 1c of the metal support body 1.

[0079] In the second embodiment, the thickness T of the metal support 1 is the sum of the thickness T1 of the first metal plate 10 and the thickness T2 of the second metal plate 20. When the metal support 1 is formed by stacking three or more metal plates, the thickness T of the metal support 1 is the sum of the thicknesses of these metal plates. In the second embodiment, the thickness T of the metal support 1 is also preferably 0.1 mm or more, more preferably 0.15 mm or more, and even more preferably 0.2 mm or more. The thickness T of the metal support 1 is preferably 1.0 mm or less, more preferably 0.75 mm or less, and even more preferably 0.5 mm or less.

[0080] In the second embodiment, the diameter D of the front-side opening 1d in the first embodiment corresponds to the diameter D1 of the first front-side opening 10d of the first through-space 10c of the first metal plate 10. This is because the first front-side surface 10a of the first metal plate 10 corresponds to the front-side surface 1a of the metal support 1 in the first embodiment. When an electrochemical element E is constructed using the metal support 1 of the second embodiment, an electrode layer 2 is formed on the first front-side surface 10a of the first metal plate 10. In the second embodiment, the diameter D1 of the first front-side opening 10d is preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 20 μm or more. The diameter D1 of the first front-side opening 10d is preferably 60 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less.

[0081] In the second embodiment, the pitch P of the arrangement of the through spaces 1c corresponds to the pitch P1 of the first through spaces 10c of the first metal plate 10. This is because the first front side surface 10a of the first metal plate 10 corresponds to the front side surface 1a of the metal support 1 in the first embodiment. When an electrochemical element E is constructed using the metal support 1 of the second embodiment, an electrode layer 2 is formed on the first front side surface 10a of the first metal plate 10. In the second embodiment, the pitch P of the arrangement of the first through spaces 10c (holes) is preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.15 mm or more. The pitch P of the arrangement of the first through spaces 10c (holes) is preferably 0.3 mm or less, more preferably 0.25 mm or less, and even more preferably 0.2 mm or less.

[0082] In the second embodiment, the area S of the front opening 1d of the through-space 1c in the first embodiment corresponds to the area S1 of the first front opening 10d of the first metal plate 10. This is because the first front side surface 10a of the first metal plate 10 corresponds to the front side surface 1a of the metal support 1 in the first embodiment. When an electrochemical element E is constructed using the metal support 1 of the second embodiment, an electrode layer 2 is formed on the first front side surface 10a of the first metal plate 10. In the second embodiment as well, the area S1 of the first front opening 10d of the first through-space 10c is 7.0 × 10 -5 mm 2 It is preferable that it is 3.0 × 10 or more. -3 mm 2It is preferable that the following is true:

[0083] In the second example, the circularity of first front-side opening 10d is preferably 0.20 or more, more preferably 0.30 or more, and even more preferably 0.40 or more, and is preferably 0.80 or less, more preferably 0.70 or less, and even more preferably 0.60 or less. Also in the second example, the area envelopment factor of the first front-side opening 10d is preferably 0.60 or more, more preferably 0.70 or more, and even more preferably 0.80 or more. The area envelopment factor of the first front-side opening 10d is preferably 0.98 or less, more preferably 0.95 or less, and even more preferably 0.90 or less. The perimeter envelopment factor of the first front-side opening 10d is preferably 0.57 or more, more preferably 0.70 or more, and even more preferably 0.80 or more. The perimeter envelopment factor of the first front-side opening 10d is preferably 0.99 or less, more preferably 0.90 or less, and even more preferably 0.85 or less.

[0084] In the second embodiment, the aperture ratio A of the metal support 1 is the proportion (aperture ratio A1) of the first front-side openings 10d in the first hole region 10g of the first metal plate 10. (The first hole region 10g is a region in the first front-side surface 10a of the first metal plate 10 where the first through-spaces 10c are formed.) This is because the first front-side surface 10a of the first metal plate 10 corresponds to the front-side surface 1a of the metal support 1. When an electrochemical element E is constructed using the metal support 1 of the second embodiment, an electrode layer 2 is formed on the first front-side surface 10a of the first metal plate 10. In the second embodiment, the aperture ratio A is preferably 0.1% or more, more preferably 0.15% or more, and even more preferably 0.7% or more. The aperture ratio A is preferably 7.0% or less, more preferably 6.0% or less, and even more preferably 5.5% or less. In the second example, the area of ​​one first hole region 10g is 9 cm 2 More than 36cm is preferable. 2 More than 81cm is preferable. 2 The above is more preferable.

[0085] The aperture ratio A1 is calculated by dividing the sum of the areas S1 of the first front-side openings 10d in the first hole region 10g by the area of ​​the first hole region 10g. Note that, as in the first example, the aperture ratio A1 can also be calculated by focusing on the areas that appear periodically in the first hole region 10g. For example, focusing on the first unit region 10h shown in FIG. 6, the value obtained by dividing the area S1 by the area of ​​the first unit region 10h (the square of the pitch P1) is approximately equal to the aperture ratio A1 of the entire first hole region 10g. That is, in the case of the orthogonal lattice shown in FIG. 6, the aperture ratio A1 can be calculated using the following equation 6. When the first front-side openings 10d are circular with a diameter D1, the following equation 7 also holds.

[0086]

number

[0087]

number

[0088] (electrode layer) As shown in FIG. 1 , the electrode layer 2 can be provided as a thin layer on the front surface of the metal support 1 in an area larger than the area where the through spaces 1c are provided. When the electrode layer 2 is a thin layer, its thickness can be, for example, about 1 μm to 100 μm, preferably 5 μm to 50 μm. Such a thickness makes it possible to reduce the amount of expensive electrode layer material used, thereby reducing costs, while ensuring sufficient electrode performance. The entire area where the through spaces 1c are provided is covered by the electrode layer 2. In other words, the through spaces 1c are formed inside the area of ​​the metal support 1 where the electrode layer 2 is formed. In other words, all of the through spaces 1c are provided facing the electrode layer 2.

[0089] Examples of materials that can be used for the electrode layer 2 include composites such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO, and Cu-CeO. In these examples, GDC, YSZ, and CeO can be referred to as aggregates of the composite. The electrode layer 2 is preferably formed by a low-temperature firing method (e.g., a wet method using a firing process at a low temperature without firing at a high temperature above 1100°C), a spray coating method (e.g., thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spray, etc.), a PVD method (e.g., sputtering, pulsed laser deposition, etc.), or a CVD method. These processes, which can be used at low temperatures, can provide a good electrode layer 2 without firing at a high temperature above 1100°C. This is preferable because it prevents damage to the metal support 1 and can suppress interdiffusion of elements between the metal support 1 and the electrode layer 2, thereby realizing an electrochemical element with excellent durability. Furthermore, the use of a low-temperature firing method is even more preferable because it makes it easier to handle the raw materials.

[0090] The electrode layer 2 has a plurality of pores inside and on the surface thereof to provide gas permeability. That is, the electrode layer 2 is formed as a porous layer. The electrode layer 2 is formed, for example, so that its density is 30% or more and less than 80%. The size of the pores can be appropriately selected so that the electrochemical reaction proceeds smoothly. Note that density is the proportion of the space occupied by the material constituting the layer, and can be expressed as (1 - porosity), and is equivalent to the relative density.

[0091] (middle class) As shown in FIG. 1, the intermediate layer 3 (insertion layer) can be formed as a thin layer on the electrode layer 2, covering the electrode layer 2. When the intermediate layer 3 is thin, its thickness can be, for example, about 1 μm to 100 μm, preferably about 2 μm to 50 μm, and more preferably about 4 μm to 25 μm. This thickness reduces the amount of expensive intermediate layer material used, thereby reducing costs, while ensuring sufficient performance. Examples of materials that can be used for the intermediate layer 3 include YSZ (yttria-stabilized zirconia), SSZ (scandium-stabilized zirconia), GDC (gadolinium-doped ceria), YDC (yttrium-doped ceria), and SDC (samarium-doped ceria). Ceria-based ceramics are particularly preferred.

[0092] The intermediate layer 3 is preferably formed by a low-temperature firing method (e.g., a wet method using firing in a low-temperature range without firing at a high temperature range above 1100°C), a spray coating method (such as thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, or cold spray), a PVD method (such as sputtering or pulsed laser deposition), or a CVD method. These film-forming processes that can be used in a low-temperature range can provide the intermediate layer 3 without firing at a high temperature range above 1100°C. This prevents interdiffusion of elements between the metal support 1 and the electrode layer 2 without damaging the metal support 1, thereby achieving an electrochemical element E with excellent durability. Furthermore, using a low-temperature firing method is more preferable because it facilitates handling of raw materials.

[0093] The intermediate layer 3 preferably has oxygen ion (oxide ion) conductivity. Furthermore, it is more preferable that the intermediate layer 3 has mixed conductivity of oxygen ions (oxide ions) and electrons. An intermediate layer 3 having these properties is suitable for application to the electrochemical element E.

[0094] (electrolyte layer) As shown in FIG. 1, the electrolyte layer 4 is formed as a thin layer on the intermediate layer 3, covering the electrode layer 2 and the intermediate layer 3. Alternatively, it may be formed as a thin film having a thickness of 10 μm or less. More specifically, as shown in FIG. 1, the electrolyte layer 4 is provided over (straddles) the intermediate layer 3 and the metal support 1. By configuring it in this way and joining the electrolyte layer 4 to the metal support 1, the electrochemical element as a whole can have excellent robustness.

[0095] 1, the electrolyte layer 4 is provided on the front surface of the metal support 1 in an area larger than the area in which the through-space 1c is provided. In other words, the through-space 1c is formed inside the area in the metal support 1 in which the electrolyte layer 4 is formed.

[0096] Furthermore, gas leakage from the electrode layer 2 and the intermediate layer 3 can be suppressed around the electrolyte layer 4. Specifically, when the electrochemical element E is used as a component of an SOFC, gas is supplied to the electrode layer 2 from the back side of the metal support 1 through the through-space 1c during operation of the SOFC. Gas leakage can be suppressed at the portion where the electrolyte layer 4 contacts the metal support 1 without providing a separate member such as a gasket. Note that, although the electrolyte layer 4 completely covers the periphery of the electrode layer 2 in this embodiment, a configuration in which the electrolyte layer 4 is provided on top of the electrode layer 2 and the intermediate layer 3 and a gasket or the like is provided around the periphery may also be adopted.

[0097] Materials that can be used for the electrolyte layer 4 include YSZ (yttria-stabilized zirconia), SSZ (scandium-stabilized zirconia), GDC (gadolinium-doped ceria), YDC (yttrium-doped ceria), SDC (samarium-doped ceria), and LSGM (strontium-magnesium-doped lanthanum gallate). Zirconia-based ceramics are particularly suitable. Using zirconia-based ceramics for the electrolyte layer 4 allows for a higher operating temperature of the SOFC using electrochemical element E compared to ceria-based ceramics. For example, when electrochemical element E is used in an SOFC, a material such as YSZ that exhibits high electrolyte performance even at high temperatures above 650°C can be used for the electrolyte layer 4. A hydrocarbon-based raw fuel, such as city gas or LPG, can be used as the raw fuel, and the raw fuel can be converted into the SOFC anode gas by steam reforming or other methods. This allows for the construction of a highly efficient SOFC system using the heat generated in the SOFC cell stack to reform the raw fuel gas.

[0098] The electrolyte layer 4 is preferably formed by a low-temperature firing method (e.g., a wet method using firing at a low temperature without firing at a high temperature above 1100°C), a spray coating method (such as thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, or cold spray), a PVD method (such as sputtering or pulsed laser deposition), or a CVD method. These low-temperature deposition processes can provide a dense electrolyte layer 4 with high airtightness and gas barrier properties without firing at a high temperature above 1100°C. This can prevent damage to the metal support 1 and inhibit interdiffusion of elements between the metal support 1 and the electrode layer 2, resulting in an electrochemical element E with excellent performance and durability. In particular, low-temperature firing and spray coating methods are preferred because they allow for low-cost devices to be realized. Furthermore, spray coating is even more preferred because it allows for a dense electrolyte layer with high airtightness and gas barrier properties to be easily obtained at low temperatures.

[0099] The electrolyte layer 4 is densely structured to prevent gas leakage of the anode gas and the cathode gas and to exhibit high ionic conductivity. The density of the electrolyte layer 4 is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. When the electrolyte layer 4 is a uniform layer, the density thereof is preferably 95% or more, and more preferably 98% or more. Furthermore, when the electrolyte layer 4 is structured in a multi-layer structure, it is preferable that at least a portion of the layers contains a layer (a dense electrolyte layer) having a density of 98% or more, and more preferably a layer (a dense electrolyte layer) having a density of 99% or more. When such a dense electrolyte layer is included as part of the electrolyte layer, it is easier to form an electrolyte layer that is dense and has high airtightness and gas barrier properties, even when the electrolyte layer is structured in a multi-layer structure.

[0100] (Reaction prevention layer) The reaction prevention layer 5 can be formed as a thin layer on the electrolyte layer 4. When the layer is thin, its thickness can be, for example, about 1 μm to 100 μm, preferably about 2 μm to 50 μm, and more preferably about 3 μm to 15 μm. This thickness reduces the amount of expensive reaction prevention layer material used, thereby reducing costs, while ensuring sufficient performance. The material for the reaction prevention layer 5 may be any material that can prevent a reaction between the components of the electrolyte layer 4 and the components of the counter electrode layer 6, such as a ceria-based material. A material containing at least one element selected from the group consisting of Sm, Gd, and Y is preferably used. It is preferable that the material for the reaction prevention layer 5 contains at least one element selected from the group consisting of Sm, Gd, and Y, and the total content of these elements is 1.0 mass % to 10 mass %. By introducing the reaction prevention layer 5 between the electrolyte layer 4 and the counter electrode layer 6, the reaction between the constituent materials of the counter electrode layer 6 and the electrolyte layer 4 is effectively suppressed, thereby improving the long-term stability of the performance of the electrochemical element E. Forming the reaction prevention layer 5 using an appropriate method that allows for formation at a processing temperature of 1100°C or less is preferable because it can suppress damage to the metal support 1 and interdiffusion of elements between the metal support 1 and the electrode layer 2, thereby achieving an electrochemical element E with excellent performance and durability. For example, the reaction prevention layer 5 can be formed by an appropriate method such as a low-temperature firing method (e.g., a wet method using a low-temperature firing process that does not involve firing at high temperatures above 1100°C), a spray coating method (thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spray, etc.), a PVD method (sputtering, pulsed laser deposition, etc.), or a CVD method. In particular, low-temperature firing methods and spray coating methods are preferable because they allow for the realization of low-cost elements. Furthermore, the use of a low-temperature firing method is more preferable since it makes it easier to handle the raw materials.

[0101] (Counter electrode layer) The counter electrode layer 6 can be formed as a thin layer on the electrolyte layer 4 or the reaction prevention layer 5. When the counter electrode layer 6 is formed as a thin layer, its thickness can be, for example, about 1 μm to 100 μm, preferably 5 μm to 50 μm. This thickness reduces the amount of expensive counter electrode layer material used, thereby reducing costs, while ensuring sufficient electrode performance. Examples of materials that can be used for the counter electrode layer 6 include composite oxides such as LSCF and LSM, ceria-based oxides, and mixtures thereof. It is particularly preferable that the counter electrode layer 6 contains a perovskite-type oxide containing two or more elements selected from the group consisting of La, Sr, Sm, Mn, Co, and Fe. The counter electrode layer 6 formed using these materials functions as a cathode.

[0102] The counter electrode layer 6 is preferably formed using a method capable of forming the counter electrode layer 6 at a processing temperature of 1100°C or less, since this method can suppress damage to the metal support 1 and interdiffusion of elements between the metal support 1 and the electrode layer 2, thereby realizing an electrochemical element E with excellent performance and durability. For example, a low-temperature firing method (e.g., a wet method using a firing process at a low temperature without firing at a high temperature above 1100°C), a spray coating method (thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spray, etc.), a PDV method (sputtering, pulsed laser deposition, etc.), a CVD method, etc., can be used as appropriate. Low-temperature firing methods and spray coating methods are particularly preferred, as they allow for low-cost elements to be realized. Furthermore, low-temperature firing methods are even more preferred, as they facilitate the handling of raw materials.

[0103] (Solid oxide fuel cell) By configuring the electrochemical element E as described above, the electrochemical element E can be used as a power generation cell of a solid oxide fuel cell. For example, a fuel gas containing hydrogen is supplied to the electrode layer 2 from the rear surface of the metal support 1 through the through-space 1c, and air is supplied to the counter electrode layer 6, which is the counter electrode of the electrode layer 2, and the electrochemical element E is operated at a temperature of, for example, 500°C to 900°C. In this case, oxygen O2 contained in the air is converted into electrons e in the counter electrode layer 6. - reacts with oxygen ions O 2- The oxygen ions O 2- The hydrogen H2 contained in the supplied fuel gas is converted into oxygen ions O2 in the electrode layer 2 through the electrolyte layer 4. 2- reacts with water H2O and electrons e - The above reaction generates an electromotive force between the electrode layer 2 and the counter electrode layer 6. In this case, the electrode layer 2 functions as the fuel electrode (anode) of the SOFC, and the counter electrode layer 6 functions as the air electrode (cathode).

[0104] (Method of manufacturing an electrochemical element) Next, a method for producing the electrochemical device E will be described.

[0105] (Electrode layer formation step) In the electrode layer formation step, the electrode layer 2 is formed as a thin film on an area of ​​the front surface of the metal support 1 that is wider than the area where the through-space 1c is provided. The through-holes in the metal support 1 can be formed by laser processing or the like. As described above, the electrode layer 2 can be formed by a low-temperature firing method (a wet method in which firing is performed at a low temperature of 1100°C or less), a spray coating method (thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spray, or the like), a PVD method (sputtering, pulsed laser deposition, or the like), a CVD method, or the like. Whichever method is used, it is preferable to perform the method at a temperature of 1100°C or less to prevent deterioration of the metal support 1.

[0106] When the electrode layer forming step is performed by a low-temperature firing method, the step is specifically performed as follows. First, a material powder for the electrode layer 2 is mixed with a solvent (dispersion medium) to form a material paste, which is then applied to the front surface of the metal support 1. The electrode layer 2 is then compression-molded (electrode layer smoothing step) and fired at 1100°C or less (electrode layer firing step). The compression molding of the electrode layer 2 can be performed by, for example, CIP (Cold Isostatic Pressing), roll pressing, or RIP (Rubber Isostatic Pressing). The electrode layer is preferably fired at a temperature of 800°C or higher and 1100°C or lower. The order of the electrode layer smoothing step and the electrode layer firing step can also be reversed. In addition, when forming an electrochemical element having an intermediate layer 3, the electrode layer smoothing step and the electrode layer firing step can be omitted, or the electrode layer smoothing step and the electrode layer firing step can be included in the intermediate layer smoothing step and the intermediate layer firing step described below. The electrode layer smoothing step can also be carried out by lapping, leveling, cutting and polishing the surface, or the like.

[0107] (Diffusion suppression layer formation step) During the firing process in the electrode layer formation step described above, a metal oxide layer 1f (diffusion-inhibiting layer) is formed on the surface of the metal support 1. It is preferable that the firing process includes a firing process in which the firing atmosphere is set to have a low oxygen partial pressure, since this effectively inhibits interdiffusion of elements and forms a high-quality metal oxide layer 1f (diffusion-inhibiting layer) with low resistance. The electrode layer formation step may also include a separate diffusion-inhibiting layer formation step, including when a coating method is used without firing. In either case, it is desirable to perform the process at a processing temperature of 1100°C or less, which is sufficient to prevent damage to the metal support 1. Furthermore, a metal oxide layer 1f (diffusion-inhibiting layer) may be formed on the surface of the metal support 1 during the firing process in the intermediate layer formation step described below.

[0108] (Intermediate layer formation step) In the intermediate layer formation step, the intermediate layer 3 is formed in a thin layer state on the electrode layer 2 so as to cover the electrode layer 2. As described above, the intermediate layer 3 can be formed by a low-temperature firing method (a wet method in which firing is performed at a low temperature of 1100°C or less), a spray coating method (such as a thermal spraying method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method (such as a sputtering method or a pulsed laser deposition method), or a CVD method. Whichever method is used, it is preferable to perform the method at a temperature of 1100°C or less in order to suppress deterioration of the metal support 1.

[0109] When the intermediate layer forming step is performed by a low-temperature firing method, the following specific example is performed. First, a material powder for the intermediate layer 3 is mixed with a solvent (dispersion medium) to form a material paste, which is then applied to the front surface of the metal support 1. The intermediate layer 3 is then compression-molded (intermediate layer smoothing step) and fired at 1100°C or lower (intermediate layer firing step). The intermediate layer 3 can be rolled by, for example, cold isostatic pressing (CIP), roll pressing, or rubber isostatic pressing (RIP). The intermediate layer 3 is preferably fired at a temperature of 800°C or higher and 1100°C or lower. This is because such a temperature allows for the formation of a high-strength intermediate layer 3 while suppressing damage and deterioration of the metal support 1. The intermediate layer 3 is more preferably fired at 1050°C or lower, and even more preferably at 1000°C or lower. This is because the lower the firing temperature for the intermediate layer 3, the more effectively the electrochemical element E can be formed while suppressing damage and deterioration of the metal support 1. The order of the intermediate layer smoothing step and the intermediate layer firing step can also be reversed. The intermediate layer smoothing step can also be carried out by lapping, leveling, cutting and polishing the surface, or the like.

[0110] (Electrolyte layer formation step) In the electrolyte layer formation step, the electrolyte layer 4 is formed as a thin layer on the intermediate layer 3, covering the electrode layer 2 and the intermediate layer 3. Alternatively, the electrolyte layer 4 may be formed as a thin film having a thickness of 10 μm or less. As described above, the electrolyte layer 4 can be formed by a low-temperature firing method (a wet method in which firing is performed at a low temperature of 1100°C or less), a spray coating method (such as a thermal spraying method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method (such as a sputtering method or a pulsed laser deposition method), or a CVD method. Whichever method is used, it is preferable to perform the formation at a temperature of 1100°C or less to prevent deterioration of the metal support 1.

[0111] In order to form a high-quality electrolyte layer 4 that is dense and has high airtightness and gas barrier properties at a temperature range of 1100° C. or less, it is desirable to perform the electrolyte layer formation step by a spray coating method. In this case, the material for the electrolyte layer 4 is sprayed toward the intermediate layer 3 on the metal support 1 to form the electrolyte layer 4.

[0112] (Reaction prevention layer formation step) In the reaction prevention layer formation step, the reaction prevention layer 5 is formed in a thin layer state on the electrolyte layer 4. As described above, the reaction prevention layer 5 can be formed by a low-temperature firing method (a wet method in which firing is performed in a low temperature range of 1100°C or less), a spray coating method (a method such as thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, or cold spray), a PVD method (a sputtering method, a pulsed laser deposition method, or the like), a CVD method, or the like. Whichever method is used, it is desirable to perform the process at a temperature of 1100°C or less in order to prevent deterioration of the metal support 1. In order to flatten the upper surface of the reaction preventive layer 5, for example, a leveling process or a cutting / polishing process may be performed on the surface after the formation of the reaction preventive layer 5, or a press process may be performed after wet formation and before firing.

[0113] (Counter electrode layer formation step) In the counter electrode layer formation step, the counter electrode layer 6 is formed in a thin layer state on the reaction prevention layer 5. As described above, the counter electrode layer 6 can be formed by a low-temperature firing method (a wet method in which firing is performed at a low temperature of 1100°C or less), a spray coating method (such as a thermal spraying method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method (such as a sputtering method or a pulsed laser deposition method), or a CVD method. Whichever method is used, it is preferable to perform the method at a temperature of 1100°C or less to suppress deterioration of the metal support 1.

[0114] In this manner, the electrochemical device E can be manufactured.

[0115] The electrochemical element E may be configured without either or both of the intermediate layer 3 (insertion layer) and the reaction prevention layer 5. That is, the electrode layer 2 and the electrolyte layer 4 may be formed in contact with each other, or the electrolyte layer 4 and the counter electrode layer 6 may be formed in contact with each other. In this case, the intermediate layer forming step and the reaction prevention layer forming step are omitted from the above-described manufacturing method. It is also possible to add a step of forming another layer or to stack multiple layers of the same type, but in either case, it is preferable to perform the process at a temperature of 1100°C or less.

[0116] Example 1 A 0.3 mm thick, 120 mm square ferritic stainless steel metal plate (metal support 1) was fabricated by varying the laser irradiation position to match the shape of a 98 mm square area from the center, creating multiple through-spaces 1c. The through-spaces 1c were created at the lattice points of an orthorhombic lattice. Six areas of the hole region 1g in which the through-spaces 1c were formed in the metal support 1 were randomly selected, and the diameter, opening ratio, circularity, area envelopment ratio, and perimeter envelopment ratio of 40 front-side openings 1d present within the area were measured, and the average values ​​were calculated. The results are shown in Table 1.

[0117] <Comparative Example 1> The metal support 1 was fabricated by laser processing a 0.3 mm thick, 120 mm square ferritic stainless steel metal plate (metal support 1) in a 98 mm square area from the center to form multiple through-spaces 1c. The through-spaces 1c were located at the lattice points of an orthorhombic lattice. The through-spaces 1c were formed by irradiating the laser so that the front-side openings 1d in the front-side hole region 1g were nearly circular. The hole region 1g in which the through-spaces 1c were formed on the metal support 1 was randomly selected, and the diameter, opening ratio, circularity, area envelopment, and perimeter envelopment of 35 front-side openings 1d were measured, and the average values ​​were calculated. The results are shown in Table 1.

[0118] [Table 1]

[0119] As is clear from the results in Table 1, the average circularity in regions 1 to 6 of the Examples was lower than that of the Comparative Example, the maximum circularity in regions 1 to 6 of the Examples was lower than that of the Comparative Example, and the minimum circularity in regions 1 to 6 of the Examples was lower than that of the Comparative Example. Furthermore, the average area envelopment in regions 1 to 6 of the Examples was lower than that of the Comparative Example, and the maximum and minimum area envelopment in regions 1 to 6 of the Examples were lower than that of the Comparative Example. The average perimeter envelopment in regions 2 to 6 of the Examples was lower than that of the Comparative Example, the maximum perimeter envelopment in regions 2 to 4 and 6 of the Examples was lower than that of the Comparative Example, and the minimum perimeter envelopment in regions 2 to 6 of the Examples was lower than that of the Comparative Example. Low circularity is more likely to generate turbulence, which promotes the supply of materials necessary for the electrochemical reaction and the discharge of products produced by the electrochemical reaction, thereby improving the power generation voltage of the electrochemical element. Furthermore, a low area coverage ratio increases the perimeter per area of ​​the opening, making it difficult for the electrode layer to sink into the holes that form the through-space. This facilitates the formation of the electrode layer on the metal support, and increases the strength of the electrochemical element. The lower the area coverage ratio and perimeter coverage ratio, the more complex the cross-sectional shape of the opening becomes, and the larger the inner surface area of ​​the through-space 1c becomes. This facilitates the generation of turbulence, facilitating the supply of materials necessary for the electrochemical reaction and the discharge of materials produced by the electrochemical reaction. For example, the power generation voltage of an electrochemical element using such a metal support 1 is improved.

[0120] Second Embodiment An electrochemical element E, an electrochemical module M, an electrochemical device Y, and an energy system Z according to the second embodiment will be described with reference to FIGS.

[0121] As shown in FIG. 2, the electrochemical element E according to the second embodiment has a U-shaped member 7 attached to the back surface of a metal support 1, and the metal support 1 and the U-shaped member 7 form a cylindrical support.

[0122] A plurality of electrochemical elements E are stacked (assembled) with current collecting members 26 sandwiched therebetween to form an electrochemical module M. The current collecting members 26 are joined to the counter electrode layer 6 of the electrochemical element E and the U-shaped member 7, electrically connecting them together.

[0123] The electrochemical module M has a gas manifold 17, current collecting members 26, termination members, and a current drawing section. One open end of the cylindrical support of the electrochemical element E, which is stacked, is connected to the gas manifold 17, and the gas is supplied from the gas manifold 17. The supplied gas flows through the inside of the cylindrical support and is supplied to the electrode layer 2 through the through space 1c of the metal support 1.

[0124] FIG. 3 shows an overview of the energy system Z and the electrochemical device Y. The energy system Z has an electrochemical device Y and a heat exchanger 53 as a waste heat utilization unit that reuses heat discharged from the electrochemical device Y. The electrochemical device Y includes an electrochemical module M, a fuel supply unit having a desulfurizer 31 and a reformer 34 and supplying fuel gas containing a reducing component to the electrochemical module M, and an inverter 38 that extracts electricity from the electrochemical module M.

[0125] Specifically, the electrochemical device Y includes a desulfurizer 31, a reforming water tank 32, a vaporizer 33, a reformer 34, a blower 35, a combustion unit 36, an inverter 38, a control unit 39, a storage container 40, and an electrochemical module M.

[0126] The desulfurizer 31 removes (desulfurizes) sulfur compounds contained in hydrocarbon raw fuel such as city gas. When sulfur compounds are contained in the raw fuel, the provision of the desulfurizer 31 can suppress the effects of the sulfur compounds on the reformer 34 or the electrochemical element E. The vaporizer 33 generates steam from the reforming water supplied from the reforming water tank 32. The reformer 34 uses the steam generated in the vaporizer 33 to steam reform the raw fuel desulfurized in the desulfurizer 31, generating a reformed gas containing hydrogen.

[0127] The electrochemical module M generates electricity by electrochemical reaction using the reformed gas supplied from the reformer 34 and the air supplied from the blower 35. The combustion section 36 mixes the reaction exhaust gas discharged from the electrochemical module M with air and combusts combustible components in the reaction exhaust gas.

[0128] The electrochemical module M has a plurality of electrochemical elements E and a gas manifold 17 . The electrochemical elements E are arranged in parallel while electrically connected to each other, and one end (lower end) of each electrochemical element E is fixed to the gas manifold 17. The electrochemical element E generates electricity by causing an electrochemical reaction between the reformed gas supplied through the gas manifold 17 and the air supplied from the blower 35.

[0129] The inverter 38 adjusts the output power of the electrochemical module M to the same voltage and frequency as the power received from a commercial grid (not shown). The control unit 39 controls the operation of the electrochemical device Y and the energy system Z.

[0130] The vaporizer 33, the reformer 34, the electrochemical module M, and the combustion section 36 are housed in a housing 40. The reformer 34 uses the combustion heat generated by the combustion of the reaction exhaust gas in the combustion section 36 to carry out a reforming process of the raw fuel.

[0131] The raw fuel is supplied to the desulfurizer 31 through a raw fuel supply path 42 by operation of a booster pump 41. The reforming water in the reforming water tank 32 is supplied to the vaporizer 33 through a reforming water supply path 44 by operation of a reforming water pump 43. The raw fuel supply path 42 merges with the reforming water supply path 44 at a location downstream of the desulfurizer 31, and the reforming water and raw fuel that have merged outside the storage container 40 are supplied to the vaporizer 33 provided inside the storage container 40.

[0132] The reforming water is vaporized in the vaporizer 33 to become water vapor. The raw fuel containing water vapor produced in the vaporizer 33 is supplied to the reformer 34 through a water vapor-containing raw fuel supply path 45. The raw fuel is steam reformed in the reformer 34 to produce a reformed gas (first gas having a reducing component) mainly composed of hydrogen gas. The reformed gas produced in the reformer 34 is supplied to the gas manifold 17 of the electrochemical module M through a reformed gas supply path 46.

[0133] The reformed gas supplied to the gas manifold 17 is distributed to the plurality of electrochemical elements E and supplied to the electrochemical elements E from the lower end, which is the connection between the electrochemical elements E and the gas manifold 17. Mainly hydrogen (reducing component) in the reformed gas is used in the electrochemical reaction in the electrochemical elements E. The reaction exhaust gas containing the remaining hydrogen gas not used in the reaction is discharged from the upper end of the electrochemical elements E to the combustion section 36.

[0134] The reaction exhaust gas is combusted in the combustion section 36 to become combustion exhaust gas, which is discharged to the outside of the storage container 40 through the combustion exhaust gas outlet 50. A combustion catalyst section 51 (e.g., a platinum-based catalyst) is arranged in the combustion exhaust gas outlet 50, and combusts and removes reducing components such as carbon monoxide and hydrogen contained in the combustion exhaust gas. The combustion exhaust gas discharged from the combustion exhaust gas outlet 50 is sent to a heat exchanger 53 through a combustion exhaust gas discharge path 52.

[0135] The heat exchanger 53 exchanges heat between the combustion exhaust gas generated by combustion in the combustion section 36 and the supplied cold water to generate hot water. In other words, the heat exchanger 53 operates as a waste heat utilization section that reuses the heat discharged from the electrochemical device Y.

[0136] Instead of the exhaust heat utilization section, a reaction exhaust gas utilization section may be provided that utilizes the reaction exhaust gas discharged (without being burned) from the electrochemical module M. The reaction exhaust gas contains the remaining hydrogen gas that was not used in the reaction in the electrochemical element E. In the reaction exhaust gas utilization section, the remaining hydrogen gas is utilized for heat utilization by combustion or for power generation using a fuel cell or the like, thereby making effective use of energy.

[0137] <Third embodiment> 4 shows another embodiment of the electrochemical module M. The electrochemical module M according to the third embodiment is configured by stacking the above-described electrochemical elements E with inter-cell connection members 71 sandwiched therebetween.

[0138] The inter-cell connection member 71 is a plate-shaped member that is electrically conductive and gas impermeable, and has grooves 72 formed on the front and back surfaces that are perpendicular to each other. The inter-cell connection member 71 can be made of a metal such as stainless steel or a metal oxide.

[0139] 4, when electrochemical elements E are stacked with this inter-cell connecting member 71 sandwiched therebetween, gas can be supplied to the electrochemical elements E through the grooves 72. More specifically, one groove 72 serves as a first gas flow path 72a, which supplies gas to the front side of the electrochemical element E, i.e., to the counter electrode layer 6. The other groove 72 serves as a second gas flow path 72b, which supplies gas from the back side of the electrochemical element E, i.e., from the back surface of the metal support 1, to the electrode layer 2 through the through-space 1c.

[0140] When this electrochemical module M is operated as a fuel cell, oxygen is supplied to the first gas flow path 72a and hydrogen is supplied to the second gas flow path 72b. This causes a reaction as a fuel cell to proceed in the electrochemical elements E, generating electromotive force and current. The generated power is extracted to the outside of the electrochemical module M from the inter-cell connection members 71 at both ends of the stacked electrochemical elements E.

[0141] In this third embodiment, grooves 72 that are perpendicular to each other are formed on the front and back surfaces of the inter-cell connection member 71, but grooves 72 that are parallel to each other can also be formed on the front and back surfaces of the inter-cell connection member 71.

[0142] (Other embodiments) (1) In the above embodiment, the electrochemical element E is used in a solid oxide fuel cell. However, the electrochemical element E can also be used in a solid oxide electrolysis cell, an oxygen sensor using a solid oxide, or the like. That is, in the above embodiment, a configuration has been described that can improve the efficiency of converting chemical energy such as fuel into electrical energy. That is, in the above embodiment, the electrochemical element E and the electrochemical module M are operated as a fuel cell, and hydrogen gas is passed through the electrode layer 2, and oxygen gas is passed through the counter electrode layer 6. Then, oxygen molecules O2 are converted into electrons e in the counter electrode layer 6. - reacts with oxygen ions O 2- The oxygen ions O 2- moves through the electrolyte layer 4 to the electrode layer 2. In the electrode layer 2, hydrogen molecules H2 are converted into oxygen ions O 2- reacts with water H2O and electrons e - The above reaction generates an electromotive force between the electrode layer 2 and the counter electrode layer 6, generating electricity. On the other hand, when the electrochemical element E and the electrochemical module M are operated as an electrolysis cell, a gas containing water vapor and carbon dioxide is passed through the electrode layer 2, and a voltage is applied between the electrode layer 2 and the counter electrode layer 6. Then, electrons e - reacts with water molecules H2O and carbon dioxide molecules CO2 to produce hydrogen molecules H2, carbon monoxide CO, and oxygen ions O 2- Oxygen ions O 2- moves through the electrolyte layer 4 to the counter electrode layer 6. In the counter electrode layer 6, oxygen ions O 2- releases electrons and becomes oxygen molecules O2. Through the above reaction, water molecules H2O are electrolyzed into hydrogen H2 and oxygen O2, and when gas containing carbon dioxide molecules CO2 is circulated, it is electrolyzed into carbon monoxide CO and oxygen O2. When a gas containing water vapor and carbon dioxide molecules CO2 is circulated, a fuel converter 91 can be provided that synthesizes various compounds such as hydrocarbons from the hydrogen and carbon monoxide produced by the electrolysis in the electrochemical element E and electrochemical module M. A fuel supply unit (not shown) can circulate the hydrocarbons produced by the fuel converter 91 to the electrochemical element E and electrochemical module M, or can extract them from this system / device and use them as fuel or chemical raw materials. In the energy system shown in FIG. 7, the electrochemical module M has a plurality of electrochemical elements E, a gas manifold 17, and a gas manifold 171. The plurality of electrochemical elements E are arranged in parallel while electrically connected to one another, with one end (lower end) of each electrochemical element E fixed to the gas manifold 17 and the other end (upper end) fixed to the gas manifold 171. The gas manifold 17 at one end (lower end) of each electrochemical element E is supplied with water vapor and carbon dioxide. Hydrogen, carbon monoxide, and the like produced by the above-described reactions in the electrochemical elements E are collected by the gas manifold 171, which communicates with the other end (upper end) of each electrochemical element E. Energy efficiency can be improved by configuring the heat exchanger 90 in Fig. 7 to operate as a waste heat utilization unit that exchanges heat between the reaction heat generated by the reaction in the fuel converter 91 and water to vaporize them, and the heat exchanger 92 in Fig. 7 to operate as a waste heat utilization unit that exchanges heat between the waste heat generated by the electrochemical element E and water vapor and carbon dioxide to preheat them. Furthermore, the power converter 93 supplies power to the electrochemical element E. As a result, the electrochemical element E functions as an electrolysis cell as described above. Therefore, according to the above configuration, it is possible to provide an electrochemical element E or the like that can improve the efficiency of converting electrical energy into chemical energy such as fuel.

[0143] (2) In the above embodiment, the electrode layer 2 is made of a composite material such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO, or Cu-CeO, and the counter electrode layer 6 is made of a composite oxide such as LSCF or LSM. The electrochemical element E configured in this manner can be used as a solid oxide fuel cell by supplying hydrogen gas to the electrode layer 2 to form a fuel electrode (anode) and air to the counter electrode layer 6 to form an air electrode (cathode). This configuration can also be modified to configure the electrochemical element E so that the electrode layer 2 serves as an air electrode and the counter electrode layer 6 serves as a fuel electrode. That is, the electrode layer 2 is made of a composite oxide such as LSCF or LSM, and the counter electrode layer 6 is made of a composite material such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO, or Cu-CeO. In the electrochemical element E configured in this manner, air can be supplied to the electrode layer 2 to make it an air electrode, and hydrogen gas can be supplied to the counter electrode layer 6 to make it a fuel electrode, so that the electrochemical element E can be used as a solid oxide fuel cell.

[0144] (3) In the above embodiment, a flat plate type or cylindrical flat plate type solid oxide fuel cell is mainly used as the electrochemical element E, but it can also be used for an electrochemical element such as a cylindrical type solid oxide fuel cell.

[0145] (4) In the above embodiment, the electrochemical device Y includes an electrochemical module M including a plurality of electrochemical elements E. However, the electrochemical device Y of the above embodiment can also be applied to a configuration including one electrochemical element E.

[0146] (5) In the above embodiment, the electrochemical element E has a U-shaped member 7 attached to the back surface of the metal support 1, and the cylindrical support is formed by two members, the metal support 1 and the U-shaped member 7. However, the cylindrical support may be formed by integrally forming the metal support 1 and the U-shaped member 7 using a single member, or the cylindrical support may be formed by using three or more members. Also, the U-shaped member 7 may be omitted and the electrode layer 2 and the like may be supported by the metal support 1.

[0147] The configurations disclosed in the above embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction occurs. Furthermore, the embodiments disclosed in this specification are merely examples, and the present invention is not limited to these, and can be modified as appropriate within the scope of the purpose of the present invention. [Industrial Applicability]

[0148] It can be used as an electrochemical device and a solid oxide fuel cell. [Explanation of symbols]

[0149] 1 Metal support 1a Front side 1b Back side 1c penetration space 1d Front opening 1e Back opening 1f Metal oxide layer 1g hole area 1h unit area T Thickness D Inner diameter, diameter, hole diameter P pitch, spacing S area (front opening) A Aperture ratio 10 1st metal plate 10a 1st front side 10b 1st back side 10c 1st penetration space 10d 1st front opening 10e First rear opening 10g 1st hole area 10h First unit area T1 Thickness D1 Inner diameter, diameter, hole diameter P1 pitch, spacing S1 area (front opening) A1 aperture ratio 20 Second metal plate 20a 2nd front side 20b 2nd back side 20c 2nd penetration space 20d 2nd front opening 20e Second rear opening T2 Thickness D2 Inner diameter, diameter, hole diameter P2 pitch, spacing

Claims

1. A metal support for an electrochemical device, comprising: The metal support has a surface on which an electrode layer is provided as a front side, and has a plurality of through spaces that penetrate from the front side to the back side, and has one or more hole regions as areas in which the through spaces are formed on the front side, and the average circularity of the openings of the through spaces on the front side in at least one of the hole regions is 0.80 or less.

2. The metal support according to claim 1 , wherein the hole region has at least one opening in the front side surface, the opening having an area coverage ratio of 0.88 to 0.

98.

3. The metal support according to claim 1 , wherein the hole region has at least one opening in the front side surface, the opening having a perimeter envelopment ratio of 0.57 or more and 0.99 or less.

4. 2. The metal support according to claim 1, wherein an opening ratio, which is a ratio of openings in the front side surface to the hole region, is 0.1% to 7.0%.

5. 2. The metal support according to claim 1, wherein the spacing between the openings on the front side surface is 0.05 mm or more and 0.3 mm or less.

6. The area of ​​the hole region is 9 cm ２ The metal support according to claim 1, wherein the metal support is as described above.

7. 2. The metal support according to claim 1, which has a thickness of 0.1 mm or more and 1.0 mm or less.

8. The metal support according to claim 1 , which is formed by stacking a plurality of metal plates.

9. 2. The metal support according to claim 1, wherein the material is an Fe-Cr alloy.

10. The metal support according to claim 1 , wherein at least a portion of the front side surface is covered with a metal oxide film.

11. An electrochemical element comprising the metal support according to any one of claims 1 to 10, and at least an electrode layer, an electrolyte layer, and a counter electrode layer provided on the front side of the metal support.

12. An electrochemical module in which a plurality of electrochemical elements according to claim 11 are arranged in a group.

13. 13. An electrochemical device comprising at least the electrochemical module according to claim 12 and a fuel converter, and comprising a fuel supply unit that supplies reducing component gas from the fuel converter to the electrochemical element or the electrochemical module, or that supplies reducing component gas from the electrochemical element or the electrochemical module to the fuel converter.

14. An electrochemical device comprising at least the electrochemical module according to claim 12 and a power converter that extracts electric power from the electrochemical element or the electrochemical module or that distributes electric power to the electrochemical element or the electrochemical module.

15. An energy system comprising: the electrochemical device according to claim 13; and a waste heat utilization section that reuses heat discharged from the electrochemical device.

16. An energy system comprising: the electrochemical device according to claim 14; and a waste heat utilization section that reuses heat discharged from the electrochemical device.

17. A solid oxide fuel cell comprising the electrochemical element according to claim 11, wherein a power generation reaction occurs in the electrochemical element.

18. A solid oxide electrolysis cell comprising the electrochemical element according to claim 11, wherein an electrolytic reaction occurs in the electrochemical element.

19. 11. A manufacturing method for manufacturing the metal support according to claim 1, wherein the plurality of through spaces extending from the front side surface to the back side surface are formed by laser processing, punching processing, or etching processing, or a combination thereof.

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