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

Abstract

The present application realizes a SOFC system in which gas is smoothly flowed into or out of through holes in a metal support mainly for a metal support type SOFC, thereby improving power generation efficiency. A metal support (1) which is integrally formed in a plate shape, has a plurality of through holes (2) which pass through from a front side (1a) on which an electrode layer (A) is provided to a back side (1b), and in which inclined through holes (2A, 2B) having a central axis inclined with respect to a thickness direction are provided as the through holes (2).

Description

Technical Field

[0001] The present invention relates to a metal support, which is integrally formed in the shape of a plate and has a plurality of through holes extending from the front side where the electrode layer is disposed to the back side. Background Technology

[0002] Existing metal-supported SOFCs (Solid Oxide Fuel Cells) are configured with multiple electrochemical elements. These elements consist of an anode electrode layer, an electrolyte layer, and a cathode electrode layer disposed on the front and side surfaces of a metal support formed as a plate with multiple through-holes. In such metal-supported SOFCs, the optimization of the shape of each through-hole formed in the metal support has been explored to improve power generation efficiency, enhance quality during mass production, or reduce costs (see, for example, Patent Document 1).

[0003] Existing technical documents Patent documents Patent document 1: International Publication No. 2019-189913. Summary of the Invention

[0004] The problem that the invention aims to solve In existing metal-supported SOFCs, gas flowing along the back side of the metal support is supplied to the electrode layer disposed on the front side of the metal support through multiple through holes formed in the metal support. Therefore, if the inflow or outflow of gas into or out of the through holes on the front and back sides of the metal support is not smooth, problems arise such as a decrease in fuel gas utilization, making it difficult to improve the power generation efficiency of the SOFC system.

[0005] In view of this fact, the main objective of the present invention is to realize an SOFC system in which gas flows smoothly into or out of a through hole in a metal support, which is mainly used in metal-supported SOFCs, thereby improving power generation efficiency.

[0006] Methods for solving problems The first feature of the metal support involved in the present invention is that it is a metal support integrally formed as a plate and has a plurality of through holes extending from the front side where the electrode layer is disposed to the back side. As the through holes, there are inclined through holes with the central axis inclined relative to the thickness direction.

[0007] According to this configuration, at least one of a plurality of through holes formed in the metal support is formed in the metal support to supply gas flowing along the back side of the metal support to the electrode layer disposed on the front side of the metal support. These through holes are formed in the form of inclined through holes with their central axis inclined relative to the thickness direction of the metal support. Here, "supplying to the electrode layer" means supplying to or receiving from the electrode layer. Therefore, in such inclined through holes, the central axis of the metal support can be inclined along the gas inflow and outflow directions of the through hole on the front or back side of the metal support. Thus, the inflow or outflow of gas into or from the inclined through holes of the metal support can be smoothly achieved. According to this configuration, the supply of gas (e.g., fuel gas or water vapor) to the electrode layer of the electrochemical element, or the discharge of gas (e.g., water vapor in the case of hydrogen as fuel gas, or electrolyzed hydrogen in the case of water vapor) from the electrode layer of the electrochemical element can be smoothly achieved, thereby improving the performance of the electrochemical element.

[0008] The second feature of the metal support according to the present invention is that: the gas flow path through which the gas supplied to the electrode layer flows is provided along the back side of the metal support, and as the inclined through hole, there is a first inclined through hole that is inclined in the metal support in a state where the opening on the front side is located downstream of the gas flow direction in the gas flow path compared with the opening on the back side.

[0009] According to this configuration, in the gas flow path provided along the back side of the metal support, the angle of change of the flow direction of the gas flowing into the first inclined through hole from the gas flow path is reduced to less than 90°, thus allowing gas to flow smoothly from the gas flow path to the first inclined through hole. Therefore, gas can be supplied to the electrode layer more smoothly from the gas passage through the first inclined through hole. It should be noted that it is preferable if the inclination angle of the center line of the through hole relative to the back side horizontal plane of the metal support is less than 90°, more preferably if it is 85° or less, and even more preferably if it is 80° or less. In addition, in order to prevent interference between adjacent through holes among multiple through holes, it is preferable if the inclination angle of the center line of the through hole relative to the back side horizontal plane of the metal support is 45° or more, more preferably if it is 50° or more, and even more preferably if it is 55° or more. In addition, the first inclined through hole can be one or multiple.

[0010] The third feature of the metal support according to the present invention is that: the gas flow path through which the gas supplied to the electrode layer flows is provided along the back side of the metal support, and as the inclined through hole, there is a second inclined through hole that is inclined in the metal support such that the opening on the back side is located downstream of the gas flow direction in the gas flow path compared with the opening on the front side.

[0011] According to this configuration, in the gas flow path provided along the back side of the metal support, the angle at which the flow direction of the gas flowing out of the gas flow path changes from the second inclined through hole is reduced to less than 90°, thus allowing gas to flow smoothly from the second inclined through hole into the gas flow path. Therefore, gas can be discharged more smoothly from the electrode layer through the second inclined through hole into the gas flow path. It should be noted that the inclination angle of the centerline of the through hole relative to the front horizontal plane of the metal support is preferably less than 90°, more preferably less than 85°, and even more preferably less than 80°. Furthermore, to prevent interference between adjacent through holes in a plurality of through holes, the inclination angle of the centerline of the through hole relative to the front horizontal plane of the metal support is preferably 45° or more, more preferably 50° or more, and even more preferably 55° or more. Additionally, the second inclined through hole can be one or more.

[0012] The fourth feature of the metal support according to the present invention is that: the gas flow path through which the gas supplied to the electrode layer flows is provided along the back side of the metal support, and as the inclined through hole, it has a first inclined through hole and a second inclined through hole. At the same time, the first inclined through hole is inclined in the metal support such that its opening on the front side is located downstream of the gas flow direction in the gas flow path compared with its opening on the back side, and the second inclined through hole is inclined in the metal support such that its opening on the back side is located downstream of the gas flow direction in the gas flow path compared with its opening on the front side.

[0013] According to this configuration, in the gas flow path provided along the back side of the metal support, the angle of change of the flow direction of the gas flowing into the first inclined through hole from the gas flow path is reduced to less than 90°, thus allowing gas to flow smoothly from the gas flow path into the first inclined through hole. Consequently, gas can be supplied to the electrode layer more smoothly from the gas passage through the first inclined through hole.

[0014] Furthermore, in the gas flow path provided along the back side of the metal support, the angle at which the flow direction of the gas flowing out of the gas flow path changes from the second inclined through hole is reduced to less than 90°, thus allowing gas to flow smoothly from the second inclined through hole into the gas flow path. Consequently, the discharge of gas from the electrode layer through the second inclined through hole into the gas flow path can be performed more smoothly.

[0015] The fifth feature of the metal support body according to the present invention is that the inclined through hole is formed in the metal support body such that the opening area on the front side is smaller than the opening area on the back side.

[0016] According to this configuration, the machining of inclined through holes becomes easier, which improves machinability and cost during mass production, making it suitable.

[0017] The sixth feature of the metal support according to the present invention is that the electrode layer has an insertion portion that is inserted into the inclined through hole.

[0018] According to this configuration, when an electrode material paste is applied to the front and side surfaces of a metal support to form an electrode layer, a portion of the paste enters the inclined through-hole to an appropriate depth, and the paste that has entered forms the aforementioned insertion portion. Furthermore, by providing such an appropriately deep insertion portion, the electrode layer can be easily formed on the metal support, while simultaneously improving the strength of the electrode layer.

[0019] The electrochemical element involved in this invention is characterized by having a metal support as described in this invention, and having an electrode layer, an electrolyte layer and a counter electrode layer disposed on the aforementioned front side of the metal support.

[0020] According to this configuration, since the constituent elements of electrochemical elements such as electrode layers, electrolyte layers, and counter electrode layers are formed on the aforementioned metal support that allows for the smooth supply of gas to or from the electrode layers, these constituent elements of electrochemical elements such as electrode layers can be thinned or made into thin films, thereby reducing the material cost of electrochemical elements and obtaining high-performance electrochemical elements.

[0021] A further feature of the electrochemical element of the present invention is that it has a turbulence promoter on at least a portion of the gas flow path through which the gas supplied to the electrode layer flows, the turbulence promoter disrupting the flow within the gas flow path.

[0022] According to this configuration, by providing a turbulence promoter on at least a portion of the gas flow path, the gas flow can be disturbed, creating a flow in a direction different from the mainstream (e.g., perpendicular to the mainstream) relative to the mainstream formed within the gas flow path. As a result, gas can be effectively supplied to the electrode layer through the through-hole.

[0023] A further feature of the electrochemical element of the present invention is that it has a catalytic reaction section in at least a portion of the gas flow path through which the gas supplied to the electrode layer passes, the catalytic reaction section reforming the fuel gas.

[0024] According to this configuration, by providing a catalytic reaction section on at least a portion of the gas flow path, a catalytic reaction can occur in the gas flowing through the gas flow path (gas supplied to the electrode layer or gas generated in the electrode layer). For example, when supplying fuel gases such as methane and hydrogen to the electrode layer to enable the electrochemical element to operate as a fuel cell, water vapor generated in the electrode layer and flowing out to the gas flow path through the through-holes can be effectively utilized for the reforming of methane contained in the fuel gas (mainly water vapor reforming).

[0025] Furthermore, if at least a portion of the surface of the aforementioned turbulence promoter is used as the reforming reaction section, in addition to controlling the gas flow in the gas flow path caused by the turbulence promoter as previously described, a reforming reaction based on the turbulence promoter (in the above example, water vapor reforming) can also be carried out.

[0026] The electrochemical module involved in this invention is characterized by being configured in a state that incorporates multiple electrochemical elements involved in this invention.

[0027] According to this configuration, since it is configured in a state in which multiple metal supports are assembled that can smoothly supply gas to the electrode layer or smoothly discharge gas from the electrode layer, material costs and processing costs can be suppressed, while a small and high-performance electrochemical module with excellent strength and reliability can be obtained.

[0028] The electrochemical device according to the present invention is characterized by comprising: an electrochemical element or an electrochemical module according to the present invention; and a fuel converter that supplies a gas containing reducing components to the electrochemical element or the electrochemical module, or a fuel converter that converts the gas containing reducing components generated in the electrochemical element or the electrochemical module.

[0029] According to this configuration, the device has the aforementioned electrochemical element or electrochemical module, and has a fuel converter that supplies the aforementioned electrochemical element or electrochemical module with a gas containing reducing components, or a fuel converter that converts the gas containing reducing components generated in the aforementioned electrochemical element or electrochemical module.

[0030] Therefore, when using electrochemical elements or modules as fuel cells, if a configuration is formed in which hydrogen is generated from natural gas supplied by existing raw material supply infrastructure such as city gas via a fuel converter such as a reformer and then circulated within the fuel cell, an electrochemical device with durable / reliable and high-performance electrochemical modules can be realized. Furthermore, since a system for recycling unused fuel gases discharged from the electrochemical module can be easily constructed, a highly efficient electrochemical device can be achieved.

[0031] When an electrochemical element or electrochemical module is operated as an electrolysis cell, it can, for example, become an electrochemical device that reacts hydrogen generated by the electrolysis of water with carbon monoxide or carbon dioxide in a fuel converter to convert it into methane, etc. With such a configuration, an electrochemical device with durable / reliable and high-performance electrochemical modules can be realized.

[0032] Another feature of the electrochemical device according to the present invention is that it includes an electrochemical element or an electrochemical module according to the present invention and a power converter, wherein the power converter extracts power from the electrochemical element or the electrochemical module or supplies power to the electrochemical element or the electrochemical module.

[0033] According to this configuration, the power converter extracts electricity generated by the electrochemical element or the electrochemical module, or supplies electricity to the electrochemical element or the electrochemical module. Thus, as described above, the electrochemical element or the electrochemical module functions as a fuel cell or as an electrolyzer. Therefore, according to the above configuration, an electrochemical element or the like can be provided that improves the efficiency of converting chemical energy such as fuel into electrical energy or converting electrical energy into chemical energy such as fuel.

[0034] For example, when using an inverter as a power converter, the electrical output obtained from high-performance electrochemical elements or electrochemical modules can be boosted by the inverter, or DC can be converted into AC. Therefore, it is easy to utilize the electrical output obtained from the electrochemical elements or electrochemical modules, and thus preferred.

[0035] The energy system according to the present invention is characterized by having an electrochemical device according to the present invention and a heat recovery utilization unit for reusing the heat discharged by the electrochemical device.

[0036] According to this configuration, since it has the aforementioned electrochemical device and a heat recovery unit that reuses the heat discharged from the electrochemical device, an energy system with excellent energy efficiency can be achieved. It should be noted that it can also be combined with a power generation system that utilizes the combustion heat of unused fuel gases discharged from the electrochemical device to generate electricity, thereby achieving a hybrid system with excellent energy efficiency.

[0037] The solid oxide fuel cell or solid oxide electrolyzer of the present invention is characterized by having the electrochemical element of the present invention, so that a power generation reaction or an electrolysis reaction occurs in the electrochemical element.

[0038] According to this configuration, high-performance electrochemical elements can be used as solid oxide fuel cells for power generation reactions, or as solid oxide electrolyzers for electrolysis reactions, thus obtaining solid oxide fuel cells or solid oxide electrolyzers with excellent power generation efficiency. It should be noted that, for example, if a solid oxide fuel cell can operate in a temperature range of 650°C or higher during rated operation, in a fuel cell system using hydrocarbon gases such as city gas as fuel, the heat required to convert the fuel into hydrogen can be supplied by the exhaust heat of the fuel cell, thus improving the power generation efficiency of the fuel cell system, which is more preferable. Furthermore, if a solid oxide fuel cell operates in a temperature range of 900°C or lower during rated operation, the suppression effect of Cr volatilization from the metal-supported electrochemical elements is improved, which is more preferable. If a solid oxide fuel cell operates in a temperature range of 850°C or lower during rated operation, the suppression effect of Cr volatilization can be further improved, which is even more preferable. Attached Figure Description

[0039] [ Figure 1 [This is a cross-sectional view showing the structure of an electrochemical element;] [ Figure 2 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 3 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 4 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 5 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 6 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 7 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 8 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 9 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 10 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 11 This is an enlarged cross-sectional view showing an example of the shape and arrangement of through holes in a metal support; [ Figure 12 [This is an enlarged cross-sectional view of the through-hole portion in an electrochemical element;] [ Figure 13 [This is a schematic diagram showing the composition of electrochemical elements and electrochemical modules;] [ Figure 14 [This is a schematic diagram showing the structure of an electrochemical device and energy system;] [ Figure 15 [This is a schematic diagram showing the structure of other electrochemical modules;] [ Figure 16 [ ] is a schematic diagram showing the configuration of other electrochemical devices and energy systems. Detailed Implementation

[0040] The embodiments of the present invention will be described with reference to the accompanying drawings.

[0041] Figure 1 The electrochemical element E shown is used, for example, as a single cell in a fuel cell, which is a component of a solid oxide fuel cell (hereinafter sometimes referred to as "SOFC") that generates electricity by accepting a supply of fuel gas containing hydrogen and air. It should be noted that, in the following description of the positional relationships of the layers, for example, when viewed from the electrolyte layer B, the side of the cathode electrode layer C is referred to as "upper" or "upper side," and the side of the anode electrode layer A is referred to as "lower" or "lower side." Furthermore, the side of the metal support 1 on which the anode electrode layer A is formed is referred to as the front side 1a, and the opposite side is referred to as the back side 1b.

[0042] In addition, the anode electrode layer A is sometimes simply referred to as the "electrode layer", and the cathode electrode layer C is sometimes simply referred to as the "counter electrode layer".

[0043] (Electrochemical element E) Electrochemical element E, such as Figure 1 As shown, the device includes a metal support 1, an anode electrode layer A formed on the metal support 1, an intermediate layer y formed on the anode electrode layer A, and an electrolyte layer B formed on the intermediate layer y. Furthermore, the electrochemical element E also includes a reaction prevention layer z formed on the electrolyte layer B and a cathode electrode layer C formed on the reaction prevention layer z. That is, the cathode electrode layer C is formed on the electrolyte layer B, and the reaction prevention layer z is formed between the electrolyte layer B and the cathode electrode layer C. The anode electrode layer A is porous, while the electrolyte layer B is dense.

[0044] The electrochemical element E has a U-shaped component 7 mounted on the back side 1b of the metal support 1, forming a cylindrical support with the metal support 1 and the U-shaped component 7. Moreover, the space enclosed by the metal support 1 and the U-shaped component 7 becomes the gas flow path L for supplying reformed gas from the gas manifold 17.

[0045] One end of the gas flow path L ( Figure 14 The upper end of the middle section is covered by a cover 74. A waste gas outlet 77 is provided in the cover 74, which discharges the reaction waste gas flowing through the gas flow path L to the outside. Figure 14 The combustion section 36 in the middle). The opposite side of the end where the cover 74 is located ( Figure 14 The lower end of the reformed gas (17) opens into the gas manifold 17, becoming the inlet for the reformed gas to enter the gas flow path L.

[0046] Furthermore, multiple (or grouped together) electrochemical elements E, with current collector 26 sandwiched in between, constitute an electrochemical module M (see reference). Figure 13 The current collector 26 is joined to the cathode electrode layer C and the U-shaped member 7 of the electrochemical element E, electrically connecting the two. It should be noted that the current collector 26 can be omitted, resulting in a configuration where the cathode electrode layer C and the U-shaped member 7 of the electrochemical element E are directly electrically connected.

[0047] (Metal support 1) Metal support 1 supports the anode electrode layer A, intermediate layer y, and electrolyte layer B to maintain the strength of electrochemical element E. That is, metal support 1 serves as a support for electrochemical element E.

[0048] The metal support 1 is made of a material with excellent electronic conductivity, heat resistance, oxidation resistance, and corrosion resistance. For example, ferritic stainless steel, austenitic stainless steel, and nickel-based alloys are used. Alloys containing chromium are particularly suitable. In this embodiment, the metal support 1 uses an Fe-Cr alloy containing 18% by mass or more and 25% by mass or less of Cr. However, Fe-Cr alloys containing 0.05% by mass or more of Mn, 0.15% by mass or more and 1.0% by mass of Ti, 0.15% by mass or more and 1.0% by mass of Zr, 0.15% by mass or more and 1.0% by mass of Ti and Zr with a total content of 0.15% by mass or more and 1.0% by mass or less of Ti, or 0.10% by mass or more and 1.0% by mass of Cu are particularly suitable.

[0049] The metal support 1 is plate-shaped. Furthermore, the metal support 1, with the side where the anode electrode layer A is located as its front side 1a, has multiple through holes 2 extending from the front side 1a to the back side 1b. These through holes 2 allow gas to pass through from the back side 1b to the front side 1a of the metal support 1. It should be noted that the plate-shaped metal support 1 can also be bent, for example, deformed into a frame shape, a cylindrical shape, or other similar shapes for use.

[0050] A diffusion inhibition layer x, composed of metal oxide, is provided on the surface of the metal support 1. That is, a diffusion inhibition layer x is formed between the metal support 1 and the anode electrode layer A (described later). The diffusion inhibition layer x is provided not only on the exposed surface of the metal support 1 but also on the contact surface (interface) with the anode electrode layer A. Additionally, it can be provided on the inner surface of the through hole 2. This diffusion inhibition layer x suppresses inter-diffusion of elements between the metal support 1 and the anode electrode layer A. For example, when using ferritic stainless steel containing chromium as the metal support 1, the diffusion inhibition layer x is mainly composed of chromium oxide. Furthermore, the diffusion inhibition layer x, with chromium oxide as its main component, suppresses the diffusion of chromium atoms from the metal support 1 into the anode electrode layer A or the electrolyte layer B. The thickness of the diffusion inhibition layer x only needs to be sufficient to balance high diffusion prevention performance and low electrical resistance.

[0051] The diffusion inhibition layer x can be formed by various methods, with the method of oxidizing the surface of the metal support 1 to form a metal oxide being suitable. Alternatively, the diffusion inhibition layer x can be formed on the surface of the metal support 1 by methods such as spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), sputtering, or PVD and CVD methods such as PLD. It can also be formed by electroplating and oxidation treatment. Furthermore, the diffusion inhibition layer x may contain a spinel phase with high conductivity.

[0052] When using ferritic stainless steel as the metal support 1, its coefficient of thermal expansion is close to that of materials such as YSZ (yttrium-stabilized zirconium oxide) or GDC (gadolinium / doped / cerium dioxide, also known as CGO), which are used as the anode electrode layer A or electrolyte layer B. Therefore, the electrochemical element E is less susceptible to damage under repeated low-temperature and high-temperature cycling. Consequently, an electrochemical element E with excellent long-term durability can be achieved, making it preferable.

[0053] (Structure of metal support 1 and through hole 2) like Figure 1 As shown, the metal support 1 is composed of a metal plate, and multiple through holes 2 are formed in the metal support 1, extending from the front side 1a where the anode electrode layer A is provided to the back side 1b.

[0054] The through hole 2 is a hole with a circular cross-section. It should be noted that the cross-sectional shape of the through hole 2 can be not only circular or approximately circular, but also rectangular, triangular, polygonal, etc., as long as a through hole 2 can be formed, various shapes can be formed within the scope of maintaining the function of the metal support 1. The through hole 2 is formed in the metal support 1 by any one or a combination of laser processing, punching, or etching. The central axis of the hole is perpendicular to the metal support 1.

[0055] Figures 2 to 11 The image shows an embodiment of the shape and configuration of the through hole 2, which is used to smoothly supply and exhaust gas to the anode electrode layer A to improve the performance of the electrochemical element E.

[0056] As shown in these embodiments, in the metal support 1, as through holes 2, there are first inclined through holes 2A and 2At and second inclined through holes 2B and 2Bt with the central axis inclined relative to the thickness direction, and parallel through holes 2C with the central axis parallel to the thickness direction.

[0057] It should also be noted that, in Figures 2 to 11 In the diagram, the lower end of the gas manifold 17 side is taken as the left side, the upper end of the combustion section 36 side is taken as the right side, and the gas flow direction F in the gas flow path L is taken as the direction from left to right, showing the cross-sectional state of the metal support 1 and the gas flow path L.

[0058] First inclined through hole 2A, 2At (refer to) Figure 2 , Figure 5-11 The second inclined through hole 2 is located downstream of the gas flow direction F in the metal support 1, with its opening on the front side relative to its opening on the back side. On the other hand, the second inclined through holes 2B and 2Bt (refer to...) Figure 3 , Figure 4 , Figure 6-11 () is a through hole 2 in the metal support 1, which is inclined in the upstream side of the gas flow direction F compared with the opening on the back side.

[0059] That is, by providing the aforementioned first inclined through holes 2A and 2At in the metal support 1, the angle of change of the flow direction of the reformed gas (H2) flowing into the first inclined through holes 2A and 2At from the gas flow path L is reduced to less than 90°. Therefore, the flow of reformed gas from the gas flow path L into the first inclined through holes 2A and 2At proceeds smoothly.

[0060] On the other hand, by providing the aforementioned second inclined through holes 2B and 2Bt in the metal support 1, the angle of change of the flow direction of water vapor (H2O) flowing out of the gas flow path L from the second inclined through holes 2B and 2Bt is reduced to less than 90°, so the water vapor flows smoothly out of the gas flow path L from the second inclined through holes 2B and 2Bt.

[0061] Moreover, in Figure 6-8 , Figure 10 , Figure 11In the illustrated configuration, along the gas flow direction F in the gas flow path L, the first inclined through holes 2A and 2At are located upstream, and the second inclined through holes 2B and 2Bt are located downstream. With this configuration, the supply of reforming gas (H2) from the gas flow path L to the anode electrode layer A through the first inclined through holes 2A and 2At, and the discharge of water vapor (H2O) from the anode electrode layer A to the gas flow path L through the second inclined through holes 2B and 2Bt, both proceed smoothly along the gas flow direction F in the gas flow path L. Furthermore, since the central axes of the first inclined through holes 2A and 2At and the second inclined through holes 2B and 2Bt intersect or approach each other on the front side (upper side in the figure) of the metal support 1, a light source such as a laser for processing the through holes 2 can be configured based on their intersection or proximity.

[0062] exist Figure 6 , Figure 8 , Figure 10 , Figure 11 In the illustrated configuration example, the metal support 1 is divided into an upstream region and a downstream region along the gas flow direction F. Multiple first inclined through holes 2A and 2At are arranged in the upstream region, and multiple second inclined through holes 2B and 2Bt are arranged in the downstream region. Furthermore, in... Figure 8 , Figure 10 , Figure 11 In the configuration example shown, parallel through holes 2C are appropriately arranged in the region between these first inclined through holes 2A and the aforementioned second inclined through holes 2B.

[0063] On the other hand, Figure 7 In the configuration example shown, a pair of inclined through holes 2At and 2Bt, each consisting of a first inclined through hole 2At and a second inclined through hole 2Bt located directly downstream of it, are arranged along the gas flow direction F.

[0064] Figure 2-5 , Figure 8-11 In the configuration example shown, the first inclined through hole 2A and the second inclined through hole 2B are shaped along the central axis and their diameters do not change. Figure 6 , Figure 7 In the configuration example shown, the first inclined through hole 2At and the second inclined through hole 2Bt are formed in the metal support 1 such that the opening area of ​​the front side 1a is smaller than the opening area of ​​the back side 1b. Specifically, a tapered shape is formed in the metal support 1 that gradually expands in diameter from the front side 1a to the back side 1b. According to this configuration, it becomes easier to process and form the inclined through holes 2A and 2B using a laser irradiated by a light source from the front side of the metal support 1.

[0065] In addition, such as Figure 12As shown, the anode electrode layer A has an insertion portion Aa that is inserted into the aforementioned inclined through hole 2. That is, when a paste of anode electrode material is applied to the front side 1a of the metal support 1 to form the anode electrode layer A, a portion of the paste enters the inclined through hole 2 to an appropriate depth, as detailed below. Then, the paste that has entered forms the aforementioned insertion portion Aa. By providing such an appropriately deep insertion portion Aa, the anode electrode layer A is easily formed on the metal support 1, and the strength of the anode electrode layer A is improved.

[0066] (Structure within gas flow path L) exist Figure 8-11 In the example shown, a turbulence promoter 80 is provided on the gas flow path L to disrupt the flow within the gas flow path 1. With this configuration, the reformed gas flow within the gas flow path 1 is disrupted, creating a flow in a direction different from the mainstream flow (e.g., perpendicular to the mainstream flow) relative to the mainstream flow formed within the gas flow path 1. As a result, the supply of reformed gas to the electrode layer A through the through-hole 2 can be performed effectively. It should also be noted that the illustration shows an example where multiple spheres are filled into the gas flow path L to form the turbulence promoter 80; a mesh structure can also be arranged on the gas flow path L to form the turbulence promoter, etc. The shape of the turbulence promoter can be appropriately modified.

[0067] In addition, such as Figure 8 , Figure 9 The example shows a turbulence promoter 80 configured throughout the gas flow path L, or as shown in the example. Figure 10 , Figure 11 As shown in the example, a turbulence promoter 80 is configured on a portion of the gas flow path L (e.g., the downstream region), and the configuration range of the turbulence promoter 80 in the gas flow path L can be appropriately set.

[0068] Moreover, in Figure 9 , Figure 10In the example shown, a catalytic reaction section 81 is pre-installed on the gas flow path L. This catalytic reaction section 81 reforms the fuel gas flowing through the gas flow path L into hydrogen. Specifically, the catalytic reaction section 81 is installed on at least a portion of the surface of the turbulence promoter 80. For example, a catalyst layer is pre-installed on the surface of the turbulence promoter 80 as the catalytic reaction section 81, and this catalyst layer is ruthenium, which is an active metal, supported on a metal oxide carrier. If this is done, when the electrochemical element E is operated as a fuel cell, in addition to the hydrogen obtained through external reforming, fuel gas (gas before reforming: specifically, a reducing gas with methane as the main component) that is to be reformed sometimes flows in the gas flow path L. Then, by returning the water vapor generated in the anode electrode layer A to the gas flow path L, the fuel gas flowing into the gas flow path L can be reformed by water vapor in the aforementioned catalytic reaction section 81. Of course, the generated hydrogen or carbon monoxide can be supplied to the anode electrode layer A downstream via the through hole 2 for power generation.

[0069] (Anode electrode layer A) like Figure 1 As shown, the anode electrode layer A can be provided as a thin layer on the front side 1a of the metal support 1 in an area larger than the area where the multiple through holes 2 are provided. When it is a thin layer, its thickness can be set to approximately 1 μm to 100 μm, preferably 5 μm to 50 μm. Achieving such a thickness reduces the amount of expensive anode electrode layer material used, thereby lowering costs, while ensuring sufficient electrode performance. The entire area where the multiple through holes 2 are provided is covered by the anode electrode layer A. That is, the multiple through holes 2 are formed inside the area in the metal support 1 where the anode electrode layer A is formed. In other words, all the through holes 2 are provided facing the anode electrode layer A.

[0070] Materials used for the anode electrode layer A can include composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2. In these examples, GDC, YSZ, and CeO2 can be referred to as the aggregates of the composite material. It should be noted that the anode electrode layer A is preferably formed using low-temperature firing methods (e.g., wet methods that use low-temperature firing instead of high-temperature firing above 1100°C), spraying methods (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD methods (sputtering or pulsed laser deposition, etc.), CVD methods, etc. By utilizing these processes that can be used in the low-temperature range, a good anode electrode layer A can be obtained without the need for high-temperature firing, such as above 1100°C. Therefore, the metal support 1 will not be damaged. In addition, the interdiffusion of elements between the metal support 1 and the anode electrode layer A can be suppressed, resulting in an electrochemical element E with excellent durability. Moreover, if a low-temperature firing method is used, the processing of raw materials becomes easier, which is further preferred.

[0071] The anode electrode layer A has multiple fine pores inside and on its surface to ensure air permeability.

[0072] That is, the anode electrode layer A is formed as a porous layer. The anode electrode layer A is formed, for example, with a density of 30% or more and less than 80%. The pore size can be appropriately selected to facilitate the electrochemical reaction. It should be noted that density refers to the proportion of the material constituting the layer in the space, which can be expressed as (1 - porosity), and is equivalent to relative density.

[0073] (Middle layer y) like Figure 1 As shown, the intermediate layer y (insertion layer) is formed on the anode electrode layer A in a thin layer state, covering the anode electrode layer A. When it is a thin layer, its thickness can be set to approximately 1 μm to 100 μm, preferably approximately 2 μm to 50 μm, and more preferably approximately 4 μm to 25 μm. Achieving such a thickness reduces the amount of expensive intermediate layer material used, thereby lowering costs, while ensuring sufficient performance. Materials for the intermediate layer y include, for example, YSZ (yttrium-stabilized zirconium oxide), SSZ (scandium-stabilized zirconium oxide), GDC (gadolinium / doped / cerium dioxide), YDC (yttrium / doped / cerium dioxide), SDC (samarium / doped / cerium dioxide), etc. Cerium dioxide-based ceramics are particularly suitable.

[0074] The intermediate layer y is preferably formed by a low-temperature firing method (e.g., a wet method that uses a low-temperature firing process instead of firing at temperatures above 1100°C), a spraying method (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), a PVD method (sputtering, pulsed laser deposition, etc.), or a CYD method. By utilizing these film-forming processes that can be used in a low-temperature range, the intermediate layer y can be obtained without the need for firing at temperatures above 1100°C. Therefore, the metal support 1 is not damaged, elemental interdiffusion between the metal support 1 and the anode electrode layer A is suppressed, and an electrochemical element E with excellent durability can be achieved. Furthermore, the use of a low-temperature firing method simplifies the processing of raw materials, and is therefore further preferred.

[0075] As the intermediate layer y, it is preferable to have oxygen ion (oxide ion) conductivity. Furthermore, it is even more preferable to have mixed conductivity of oxygen ion (oxide ion) and electrons. Intermediate layer y with these properties is suitable for application in electrochemical element E.

[0076] (Electrolyte layer B) like Figure 1 As shown, the electrolyte layer B is formed on the intermediate layer y in a thin layer state, covering the anode electrode layer A and the intermediate layer y. Alternatively, it can be formed as a thin film with a thickness of 10 μm or less. More specifically, as... Figure 1 As shown, the electrolyte layer B is disposed over (across) the intermediate layer y and the metal support 1. By constructing it in this way and bonding the electrolyte layer B to the metal support 1, the overall robustness of the electrochemical device can be achieved.

[0077] like Figure 1 As shown, the electrolyte layer B is disposed in a region larger than the region where the plurality of through holes 2 are formed on the front side 1a of the metal support 1. That is, the plurality of through holes 2 are formed inside the region in the metal support 1 where the electrolyte layer B is formed.

[0078] Gas leakage from the anode electrode layer A and the intermediate layer y can be suppressed around the electrolyte layer B. This is explained below: When using the electrochemical element E as a single cell in a SOFC fuel cell, gas is supplied to the anode electrode layer A from the back side of the metal support 1 through the through-hole 2 during SOFC operation. Gas leakage can be suppressed without the need for sealing gaskets or other components at the contact point between the electrolyte layer B and the metal support 1. It should be noted that although in this embodiment the electrolyte layer B completely covers the area around the anode electrode layer A, it is also possible to configure the electrolyte layer B to be positioned above the anode electrode layer A and the intermediate layer y, with sealing gaskets or similar components placed around it.

[0079] For the electrolyte layer B, electrolyte materials that conduct oxygen ions, such as YSZ (yttrium-stabilized zirconium oxide), SSZ (scandium-stabilized zirconium oxide), GDC (gadolinium / doped / cerium dioxide), YDC (yttrium / doped / cerium dioxide), SDC (samarium / doped / cerium dioxide), and LSGM (strontium / magnesium-added lanthanum gallate), or electrolyte materials that conduct hydrogen ions, such as perovskite oxides, can be used. Zirconia-based ceramics are particularly suitable. If the electrolyte layer B is made of zirconium-based ceramic, the operating temperature of the SOFC using electrochemical element E can be increased compared to cerium dioxide-based ceramics or various hydrogen ion conductive materials. For example, when using electrochemical element E in SOFC, if the following system configuration is formed: using a material such as YSZ that can exhibit high electrolyte performance even in high temperature ranges above around 650°C as the electrolyte layer B, using hydrocarbon-based fuels such as city gas or LPG in the system's raw fuel, and reforming the raw fuel through steam to become the anode gas of SOFC, then a highly efficient SOFC system can be constructed that uses the heat generated in the SOFC battery stack for the reforming of the raw fuel gas.

[0080] The electrolyte layer B is preferably formed by a low-temperature firing method (e.g., a wet method that uses a low-temperature firing process instead of firing at temperatures exceeding 1100°C), a spraying method (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), a PVD method (sputtering, pulsed laser deposition, etc.), or a CVD method. By utilizing these film-forming processes that can be used in the low-temperature range, a dense electrolyte layer B with high gas tightness and gas barrier properties can be obtained without the need for firing at temperatures exceeding 1100°C. Therefore, damage to the metal support 1 can be suppressed, and furthermore, elemental interdiffusion between the metal support 1 and the anode electrode layer A can be suppressed, resulting in an electrochemical device E with excellent performance and durability. In particular, low-cost devices can be achieved by using methods such as low-temperature firing or spraying, which is therefore preferred. Moreover, if a spraying method is used, a dense electrolyte layer B with high gas tightness and gas barrier properties can be easily obtained in the low-temperature range, which is further preferred.

[0081] Electrolyte layer B is densely constructed to shield against gas leakage from the anolyte or cathode gas and to exhibit high ion conductivity. The density of electrolyte layer B is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. When electrolyte layer B is a uniform layer, its density is preferably 95% or more, more preferably 98% or more. Furthermore, when electrolyte layer B is constructed as multiple layers, it is preferable that at least a portion of it contains a layer with a density of 98% or more (dense electrolyte layer), more preferably a layer with a density of 99% or more (dense electrolyte layer). This is because if a portion of the electrolyte layer contains such a dense electrolyte layer, even when the electrolyte layer is constructed as multiple layers, a dense electrolyte layer with high gas tightness and gas barrier properties can be easily formed.

[0082] (Reaction prevention layer z) A reaction prevention layer z can be formed on the electrolyte layer B in a thin layer state. When it is a thin layer, its thickness can be set to approximately 1 μm to 100 μm, preferably approximately 2 μm to 50 μm, and more preferably approximately 3 μm to 15 μm. Achieving such a thickness reduces the amount of expensive reaction prevention layer material used, thereby lowering costs, while ensuring sufficient performance. The material for the reaction prevention layer z can be any material that prevents reaction between the components of the electrolyte layer B and the components of the cathode electrode layer C, such as cerium dioxide-based materials. Furthermore, it is suitable to use a material containing at least one element selected from Sm, Gd, and Y as the material for the reaction prevention layer z. It should be noted that it is preferable to contain at least one element selected from Sm, Gd, and Y, and the total content of these elements is 1.0% by mass or more and 10% by mass or less. By introducing the reaction prevention layer z between the electrolyte layer B and the cathode electrode layer C, the reaction between the constituent materials of the cathode electrode layer C and the constituent materials of the electrolyte layer B is effectively suppressed, thereby improving the long-term stability of the electrochemical element E. If the formation of the reaction prevention layer z is carried out using a method that can be formed at a processing temperature below 1100°C, damage to the metal support 1 can be suppressed. Furthermore, elemental interdiffusion between the metal support 1 and the anode electrode layer A can be suppressed, resulting in an electrochemical element E with excellent performance and durability. Therefore, this is preferable. For example, appropriate methods can be used, such as low-temperature firing (e.g., a wet method that uses a low-temperature firing process instead of firing at temperatures exceeding 1100°C), spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD (sputtering, pulsed laser deposition, etc.), and CVD. In particular, using low-temperature firing or spraying methods allows for the creation of low-cost components, which is preferable. Moreover, using low-temperature firing simplifies the processing of raw materials, making it even more preferable.

[0083] (Cathode electrode layer C) The cathode electrode layer C can be formed as a thin layer on top of the electrolyte layer B or the reaction prevention layer z. When it is a thin layer, its thickness can be, for example, about 1 μm to 100 μm, preferably 5 μm to 50 μm. Forming such a thickness reduces the amount of expensive cathode electrode layer C material used, thereby lowering costs, while ensuring sufficient electrode performance. Materials for the cathode electrode layer C include, for example, composite oxides such as LSCF and LSM, cerium dioxide-based oxides, and mixtures thereof. Particularly preferred materials are perovskite-type oxides containing two or more elements selected from La, Sr, Sm, Mn, Co, and Fe. The cathode electrode layer C constructed using the above materials functions as a cathode.

[0084] It should be noted that if the cathode electrode layer C is formed using a method that allows it to be formed at a processing temperature below 1100°C, damage to the metal support 1 can be suppressed. Furthermore, elemental interdiffusion between the metal support 1 and the anode electrode layer A can be suppressed, resulting in an electrochemical element E with excellent performance and durability. Therefore, this method is preferred. For example, appropriate methods can be used, such as low-temperature firing (e.g., a wet method that uses a low-temperature firing process instead of firing at temperatures exceeding 1100°C), spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PDV (sputtering, pulsed laser deposition, etc.), and CVD. In particular, using low-temperature firing or spraying methods allows for the creation of low-cost components, which is preferred. Moreover, using low-temperature firing simplifies the processing of raw materials, making this method even more preferred.

[0085] (SOFC) When the electrochemical element E is constructed in the manner described above, and thus functions as a single cell in a fuel cell, the electrochemical element E can be used as a single cell in a SOFC. For example, hydrogen-containing fuel gas flows from the back side 1b of the metal support 1 through multiple through holes 2 to the anode electrode layer A, and air flows to the cathode electrode layer C, which is the opposite electrode of the anode electrode layer A, for example, operating at a temperature above 500°C and below 900°C. In this way, oxygen O2 contained in the air in the cathode electrode layer C reacts with electrons... - The reaction produces oxygen ions O. 2- The oxygen ion O 2- It moves from the electrolyte layer B to the anode electrode layer A. In the anode electrode layer A, the hydrogen (H2) and oxygen ions (O2) contained in the supplied fuel gas... 2- The reaction produces water (H2O) (water vapor) and electrons (e). - .

[0086] When an electrolyte material that conducts hydrogen ions is used in electrolyte layer B, the hydrogen (H2) contained in the fuel gas flowing in anode electrode layer A releases electrons (e). - And generate hydrogen ions H + The hydrogen ion H + It moves from the electrolyte layer B to the cathode electrode layer C. In the cathode electrode layer C, the oxygen (O2) and hydrogen ions (H2O) contained in the air... + Electronic e - The reaction produces water (H2O).

[0087] Through the above reaction, an electromotive force is generated between the anode electrode layer A and the cathode electrode layer C. In this case, the anode electrode layer A functions as the fuel electrode (anode) of the SOFC, and the cathode electrode layer C functions as the air electrode (cathode).

[0088] (Manufacturing method of electrochemical element E) Next, the manufacturing method of electrochemical element E will be explained.

[0089] (Anode electrode layer formation steps) In the anode electrode layer formation step, the anode electrode layer A is formed in a thin film state on a region larger than the region where multiple through holes 2 are provided on the front side 1a of the metal support 1. Multiple through holes 2 can be provided on the metal support 1 by laser processing or the like. As described above, the anode electrode layer A can be formed using methods such as low-temperature firing (wet method with firing treatment at a low temperature range below 1100°C), spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD (sputtering, pulsed laser deposition, etc.), and CVD. Even when using any of these methods, it is desirable to perform the process at a temperature below 1100°C to suppress the deterioration of the metal support 1.

[0090] When forming the anode electrode layer using a low-temperature firing method, the process is specifically as follows: First, the material powder for the anode electrode layer A is mixed with a solvent (dispersion medium) to prepare a material paste, which is then coated onto the front side 1a of the metal support 1. Next, the anode electrode layer A is compressed (anode electrode layer smoothing process) and fired at 1100°C or below (anode electrode layer firing process). The compression molding of the anode electrode layer A can be performed, for example, by CIP (Cold Isostatic Pressing), roll forming, or RIP (Rubber Isostatic Pressing). Furthermore, the firing of the anode electrode layer A is suitable to be performed at a temperature between 800°C and 1100°C. Additionally, the order of the anode electrode layer smoothing process and the anode electrode layer firing process can be changed.

[0091] It should be noted that, in the case of forming an electrochemical element E with an intermediate layer y, the anode electrode layer smoothing process or the anode electrode layer firing process may be omitted, or the intermediate layer smoothing process or the intermediate layer firing process described later may include the anode electrode layer smoothing process or the anode electrode layer firing process.

[0092] It should be noted that the anode electrode layer smoothing process can also be carried out by grinding or leveling, surface cutting / polishing, etc.

[0093] Furthermore, in the compression molding of the aforementioned anode electrode layer A, a portion of the material paste coated on the front side 1a of the metal support 1 penetrates into the through hole 2 formed in the metal support 1 to an appropriate depth, and this penetrated portion becomes the aforementioned insertion portion Aa (see reference). Figure 12 ).

[0094] (Steps for forming the diffusion inhibition layer) During the firing process in the aforementioned anode electrode layer formation step, a diffusion inhibition layer x is formed on the surface of the metal support 1. It should be noted that if the firing process includes a firing environment with low oxygen partial pressure, the interdiffusion inhibition effect of elements is high, resulting in a high-quality diffusion inhibition layer x with low resistivity, which is therefore preferable. Even if the anode electrode layer formation step is a coating method without firing, an additional diffusion inhibition layer formation step may be included. In either case, it is desirable to perform the process at a processing temperature below 1100°C, which can suppress damage to the metal support 1. Furthermore, during the firing process in the intermediate layer formation step described later, the diffusion inhibition layer x can be formed on the surface of the metal support 1.

[0095] (Steps for forming the intermediate layer) In the intermediate layer formation step, an intermediate layer y is formed on the anode electrode layer A in a thin layer state, covering the anode electrode layer A. As described above, the intermediate layer y can be formed using methods such as low-temperature firing (wet method with firing treatment at a low temperature range below 1100°C), spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD (sputtering, pulsed laser deposition, etc.), and CVD. Even when using any of these methods, it is desirable to perform the process at a temperature below 1100°C to suppress the deterioration of the metal support 1.

[0096] In the case of forming the intermediate layer using a low-temperature firing method, specifically, it is carried out in the manner shown in the following example.

[0097] First, the material powder of the intermediate layer y is mixed with a solvent (dispersion medium) to prepare a material paste, which is then coated onto the front and side surfaces 1a of the metal support 1. Next, the intermediate layer y is compressed and molded (intermediate layer smoothing process), and then fired at 1100°C or below (intermediate layer firing process). The calendering of the intermediate layer y can be performed, for example, by CIP (Cold Isostatic Pressing), roll forming, or RIP (Rubber Isostatic Pressing). Furthermore, the firing of the intermediate layer y is best performed at a temperature between 800°C and 1100°C. This is because such a temperature can suppress damage / deterioration of the metal support 1 while simultaneously forming a high-strength intermediate layer y. Furthermore, firing the intermediate layer y at 1050°C or below is more preferable, and firing it at 1000°C or below is even more preferable. This is because the lower the firing temperature of the intermediate layer y, the more effectively damage / deterioration of the metal support 1 can be suppressed, and the more effectively the electrochemical element E can be formed. In addition, the order of the intermediate layer smoothing process and the intermediate layer firing process can be changed.

[0098] It should be noted that the intermediate layer smoothing process can also be carried out by grinding or leveling, surface cutting / polishing, etc.

[0099] (Electrolyte layer formation steps) In the electrolyte layer formation step, the electrolyte layer B is formed in a thin layer state on top of the intermediate layer y, covering the anode electrode layer A and the intermediate layer y. Alternatively, it can be formed in a thin film state with a thickness of 10 μm or less. As described above, the electrolyte layer B can be formed using methods such as low-temperature firing (wet method with firing treatment at a low temperature range below 1100°C), spraying (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD (sputtering, pulsed laser deposition, etc.), and CVD. Even when using any of these methods, it is desirable to perform the process at a temperature below 1100°C to suppress the deterioration of the metal support 1.

[0100] To form a dense, airtight, and high-barrier electrolyte layer B within a temperature range below 1100°C, it is desirable to perform the electrolyte layer formation step by spraying. In this case, the material of electrolyte layer B is sprayed toward the intermediate layer y on the metal support 1 to form electrolyte layer B.

[0101] (Reaction to prevent layer formation step) In the reaction prevention layer formation step, the reaction prevention layer z is formed on the electrolyte layer B in a thin layer state. As described above, the reaction prevention layer z can be formed by low-temperature firing (wet method with firing treatment in a low temperature range below 1100°C), spraying method (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD method (sputtering, pulsed laser deposition, etc.), CVD method, etc. Even if any method is used, it is desirable to carry out the process at a temperature below 1100°C to suppress the deterioration of the metal support 1. It should be noted that, in order to make the upper surface of the reaction prevention layer z flat, for example, a leveling treatment or a cutting / polishing treatment can be performed after the reaction prevention layer z is formed, or a pressure processing can be performed after wet formation and before firing.

[0102] (Cathode electrode layer formation steps) In the cathode electrode layer formation step, the cathode electrode layer C is formed on the reaction prevention layer z in a thin layer state. As described above, the cathode electrode layer C can be formed by low-temperature firing (wet method with firing treatment in a low temperature range below 1100°C), spraying method (spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, cold spraying, etc.), PVD method (sputtering, pulsed laser deposition, etc.), CVD method, etc. Even when any method is used, it is desirable to carry out the process at a temperature below 1100°C to suppress the deterioration of the metal support 1.

[0103] The above steps can be used to manufacture electrochemical element E.

[0104] It should be noted that the electrochemical element E may also be configured without either or both of the intermediate layer y (insertion layer) and the reaction prevention layer z. That is, it may be formed by contacting the anode electrode layer A with the electrolyte layer B, or by contacting the electrolyte layer B with the cathode electrode layer C. In this case, the intermediate layer formation step and the reaction prevention layer formation step are omitted in the above manufacturing method. It should also be noted that additional steps for forming other layers may be added, or multiple layers of the same type may be stacked, but even in either case, it is desirable to perform the process at a temperature below 1100°C.

[0105] (Electrochemical Module M) like Figure 14 As shown, the electrochemical module M has a gas manifold 17, a current collector 26, a terminal component, and a current lead-out section. Multiple stacked electrochemical elements E are connected to an open end of a cylindrical support on the gas manifold 17, receiving gas supply from the gas manifold 17. The supplied gas flows through the interior of the cylindrical support and is supplied to the anode electrode layer A through a through-hole 2 in the metal support 1.

[0106] (Energy system Z and electrochemical device Y) like Figure 3 As shown, the energy system Z has an electrochemical device Y and a heat exchanger 53 as a heat recovery utilization unit, which reuses the heat discharged by the electrochemical device Y.

[0107] The electrochemical device Y includes: an electrochemical module M; a fuel supply unit having a fuel converter consisting of a desulfurizer 31 and an external reformer 34, which supplies fuel gas containing reducing components to the electrochemical module M; and an inverter 38 (an example of an electric converter) which extracts electricity from the electrochemical module M.

[0108] The electrochemical device Y includes a desulfurizer 31, a reforming water tank 32, a gasifier 33, an external 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.

[0109] The desulfurizer 31 removes sulfur compounds from hydrocarbon-based raw materials such as city gas (desulfurization). When the raw materials contain sulfur compounds, the desulfurizer 31 helps to suppress the effects of these compounds on the external reformer 34 or the electrochemical element E. The gasifier 33 generates steam from reforming water supplied from the reforming water tank 32. The external reformer 34 uses the steam generated in the gasifier 33 to perform steam reforming on the desulfurized raw materials in the desulfurizer 31, producing reformed gas containing hydrogen.

[0110] The electrochemical module M generates electricity by using reformed gas supplied by the external reformer 34 and air supplied by the blower 35 to carry out an electrochemical reaction. The combustion section 36 mixes the reaction waste gas discharged from the electrochemical module M with air, causing the combustible components in the reaction waste gas to burn.

[0111] The electrochemical module M has multiple electrochemical elements E and a gas manifold 17. The multiple electrochemical elements E are arranged in parallel in an electrically connected state, and one end (lower end) of the electrochemical element E is fixed to the gas manifold 17. The electrochemical element E generates electricity by electrochemically reacting the reformed gas supplied through the gas manifold 17 with the air supplied by the blower 35.

[0112] Inverter 38 adjusts the output power of electrochemical module M to achieve the same voltage and frequency as the power received from the commercial system (not shown). Control unit 39 controls the operation of electrochemical device Y and energy system Z.

[0113] The gasifier 33, external reformer 34, electrochemical module M, and combustion section 36 are housed within the housing 40. Furthermore, the external reformer 34 utilizes the heat of combustion generated from the combustion of the reaction exhaust gas in the combustion section 36 to reform the raw materials.

[0114] Raw materials are supplied to the desulfurizer 31 via the raw material supply path 42 through the operation of the booster pump 41. Reformed water from the reformed water tank 32 is supplied to the gasifier 33 via the reformed water supply path 44 through the operation of the reformed water pump 43. Then, the raw material supply path 42 merges with the reformed water supply path 44 at the downstream side of the desulfurizer 31, and the merged reformed water and raw materials outside the receiving container 40 are supplied to the gasifier 33 located inside the receiving container 40.

[0115] Reformed water is vaporized into water vapor in vaporizer 33. The raw material containing the water vapor generated in vaporizer 33 is supplied to external reformer 34 via raw material supply path 45 containing water vapor. In external reformer 34, the raw material is reformed by water vapor to generate reformed gas (a first gas with reducing components) with hydrogen as the main component. The reformed gas generated in external reformer 34 is supplied to the gas manifold 17 of electrochemical module M via reformed gas supply path 46.

[0116] The reformed gas supplied to the gas manifold 17 is distributed to multiple electrochemical elements E, and is supplied to the electrochemical elements E from the lower end, which serves as the connection between the electrochemical elements E and the gas manifold 17. The main hydrogen (reducing component) in the reformed gas is used in the electrochemical reaction within the electrochemical elements E. The reaction exhaust gas, containing residual hydrogen not used in the reaction, is discharged from the upper end of the electrochemical elements E to the combustion section 36.

[0117] The reaction waste gas is burned in the combustion section 36 to become combustion waste gas, which is discharged from the combustion waste gas outlet 50 to the outside of the receiving container 40. A combustion catalyst section 51 (e.g., a platinum-based catalyst) is disposed in the combustion waste gas outlet 50 to burn off reducing components such as carbon monoxide or hydrogen contained in the combustion waste gas. The combustion waste gas discharged from the combustion waste gas outlet 50 is transported to the heat exchanger 53 through the combustion waste gas discharge path 52.

[0118] The heat exchanger 53 exchanges heat between the combustion exhaust gas generated in the combustion section 36 and the supplied cold water to generate hot water. That is, the heat exchanger 53 operates as a heat recovery unit that reuses the heat discharged from the electrochemical device Y.

[0119] It should be noted that a reaction waste gas utilization unit can be installed to utilize the reaction waste gas discharged from the electrochemical module M (unburned) instead of a heat recovery unit. The reaction waste gas contains residual hydrogen gas that was not used in the reaction within the electrochemical element E. In the reaction waste gas utilization unit, the residual hydrogen gas is used for heat recovery based on combustion or for power generation based on fuel cells, achieving efficient energy utilization.

[0120] [Other Implementation Methods] Other embodiments of the present invention will be described below. It should also be noted that the configurations of the embodiments described below are not limited to their individual applications, but can also be combined with the configurations of other embodiments.

[0121] (1) Other implementation methods of electrochemical module M are shown in [reference]. Figure 15 The electrochemical module M consists of the electrochemical element E stacked in the middle with the inter-unit connecting member 71 sandwiched in between.

[0122] The inter-unit connecting member 71 is a plate-shaped member that is conductive and airtight, with mutually perpendicular grooves 72 formed on its surface and back. The inter-unit connecting member 71 can be made of metals such as stainless steel or metal oxides.

[0123] like Figure 15 As shown, if the inter-unit connecting member 71 is sandwiched in the middle to stack the electrochemical element E, gas can be supplied to the electrochemical element E through the groove 72. Specifically, one groove 72 becomes a first gas flow path 72a, supplying gas to the front side of the electrochemical element E, i.e., the cathode electrode layer C. The other groove 72 becomes a second gas flow path 72b, supplying gas from the back side of the electrochemical element E, i.e., the back side of the metal support 1, through the through hole 2 (see reference). Figure 1 Gas is supplied to the anode electrode layer A.

[0124] When the 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. In this way, a reaction, functioning as a fuel cell, takes place in the electrochemical element E, generating an electromotive force / current. The generated electricity is extracted from the inter-unit connection members 71 at both ends of the stacked electrochemical element E to the outside of the electrochemical module M.

[0125] It should be noted that, in Figure 15 In the configuration shown, mutually perpendicular grooves 72 are formed on the surface and back of the inter-unit connecting member 71, but mutually parallel grooves 72 may also be formed on the surface and back of the inter-unit connecting member 71.

[0126] (2) In the above embodiments, the electrochemical element E is used in a single cell of SOFC, but the electrochemical element E can also be used in a solid oxide type electrolytic cell or an oxygen sensor that utilizes solid oxides, etc.

[0127] That is, in the above embodiments, a configuration that can improve the efficiency of converting chemical energy such as fuel into electrical energy has been described.

[0128] That is, in the above embodiment, the electrochemical element E and the electrochemical module M are operated as a fuel cell, with hydrogen flowing through the anode electrode layer A and oxygen flowing through the cathode electrode layer C. In this way, oxygen molecules O2 and electrons e in the cathode electrode layer C... - The reaction produces oxygen ions O. 2- Its oxygen ions O 2- It moves from electrolyte layer B to anode electrode layer A. In anode electrode layer A, hydrogen molecules H2 and oxygen ions O2... 2- The reaction produces water (H₂O) and electrons (e). - Through the above reactions, an electromotive force is generated between the anode electrode layer A and the cathode electrode layer C, thus generating electricity.

[0129] On the other hand, when the electrochemical element E and the electrochemical module M are operated as an electrolytic cell, a gas containing water vapor or carbon dioxide is allowed to flow through the anode electrode layer A, and a voltage is applied between the anode electrode layer A and the cathode electrode layer C. In this way, electrons e in the anode electrode layer A... - It reacts with water molecules (H2O) and carbon dioxide molecules (CO2) to become hydrogen molecules (H2) or carbon monoxide (CO) and oxygen ions (O). 2- Oxygen ions (O) 2- Oxygen ions migrate from electrolyte layer B to cathode electrode layer C. In cathode electrode layer C, oxygen ions... 2- Electrons are released to become oxygen molecules (O2). Through the above reaction, when a gas containing carbon dioxide molecules (CO2) flows through hydrogen (H2) and oxygen (O2), water molecules (H2O) are electrolyzed into carbon monoxide (CO) and oxygen (O2).

[0130] When a gas containing water vapor and carbon dioxide molecules (CO2) is circulated, a fuel converter 91 can be provided, which synthesizes various compounds such as hydrocarbons from hydrogen and carbon monoxide generated by electrolysis in the electrochemical element E and electrochemical module M. The hydrocarbons generated by the fuel converter 91 can be removed from this system / device for use as other fuels via a fuel supply unit (not shown). Alternatively, hydrogen or carbon monoxide can be converted into chemical feedstocks for utilization in the fuel converter 91.

[0131] exist Figure 16In the energy system shown, the electrochemical module M has multiple electrochemical elements E, a gas manifold 17, and a gas manifold 171. The multiple electrochemical elements E are arranged side-by-side in an electrically connected state. One end (lower end) of each electrochemical element E is fixed to the gas manifold 17, and the other end (upper end) is fixed to the gas manifold 171. The gas manifold 17 at one end (lower end) of the electrochemical element E receives a supply of water vapor and carbon dioxide. Furthermore, hydrogen and carbon monoxide generated in the electrochemical element E through the aforementioned reaction are collected by the manifold 171, which is connected to the other end (upper end) of the electrochemical element E.

[0132] make Figure 16 The heat exchanger 90 in the middle works as a heat recovery utilization unit that exchanges heat between the reaction heat generated by the reaction occurring in the fuel converter 91 and water and vaporizes it, while simultaneously making Figure 16 The heat exchanger 92 in the middle works as a heat exhaust utilization unit that exchanges heat with water vapor and carbon dioxide generated by the electrochemical element E and preheats them. By making such a configuration, energy efficiency can be improved.

[0133] In addition, the power converter 93 transmits electricity through the electrochemical element E. Thus, as described above, the electrochemical element E functions as an electrolytic cell.

[0134] Therefore, based on the above configuration, an electrochemical element E, etc., can be provided that can improve the efficiency of converting electrical energy into chemical energy such as fuel.

[0135] (3) In the above embodiments, composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2 are used as the materials for the anode electrode layer A, and composite oxides such as LSCF and LSM are used as the materials for the cathode electrode layer C. The electrochemical element E thus configured can supply hydrogen to the anode electrode layer A to become the fuel electrode (anode) and supply air to the cathode electrode layer C to become the air electrode (cathode), serving as a single cell for SOFC. This configuration can also be modified to allow the anode electrode layer A to become the air electrode and the cathode electrode layer C to become the fuel electrode. That is, composite oxides such as LSCF and LSM are used as the materials for the anode electrode layer A, and composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2 are used as the materials for the cathode electrode layer C. If the electrochemical element E is configured in this way, air can be supplied to the anode electrode layer A to form an air electrode, and hydrogen can be supplied to the cathode electrode layer C to form a fuel electrode, so that the electrochemical element E can be used as a single cell of SOFC.

[0136] (4) In the above embodiments, a flat-plate or cylindrical flat-plate solid oxide fuel cell (SOFC) is mainly used as the electrochemical element E, but it can also be used as an electrochemical element of a cylindrical solid oxide fuel cell, etc.

[0137] (5) In the above embodiment, the electrochemical device Y includes an electrochemical module M, which has a plurality of electrochemical elements E. However, the electrochemical device Y of the above embodiment can also be applied to a configuration having a single electrochemical element E.

[0138] (6) In the above embodiment, the electrochemical element E is configured such that a U-shaped component 7 is mounted on the back of the metal support 1 and the two components, the metal support 1 and the U-shaped component 7, form a cylindrical support. However, it can also be configured to use one component to form the metal support 1 and the U-shaped component 7 into a cylindrical support. In addition, it can also use three or more components to form a cylindrical support.

[0139] Alternatively, the U-shaped component 7 can be omitted, resulting in a configuration where the anode electrode layer A is supported by the metal support 1.

[0140] Symbol Explanation 1: Metal support; 1a: Front and side views; 1b: Dorsal side view; 2: Through hole; 2A, 2At: First inclined through hole; 2B, 2Bt: Second inclined through hole; 91: Fuel converter; 93: Power converter: A: Anode electrode layer (electrode layer); Aa: Insertion part; B: Electrolyte layer; C: Cathode electrode layer; E: Electrochemical element; F: Direction of gas flow; L: Gas flow path; M: Electrochemical module; Y: Electrochemical device; Z: Energy system.

Claims

1. A metal support, which is integrally formed in the shape of a plate and has multiple through holes extending from the front side where the electrode layer is disposed to the back side. The aforementioned through hole has an inclined through hole whose central axis is tilted relative to the thickness direction. The gas flow path for the gas supplied to the electrode layer is provided along the back side of the metal support. In the gas flow path described above, gas flows in the gas flow direction from an inlet located at one end to an outlet located at the other end. As the aforementioned inclined through hole, it has a first inclined through hole and a second inclined through hole, and at the same time The aforementioned first inclined through hole is located downstream of the gas flow direction in the gas flow path in the aforementioned metal support body, compared to the opening on the back side; and the inclination angle of the centerline of the through hole relative to the horizontal plane on the back side of the metal support body is 45˚ or more and 85˚ or less. The second inclined through hole is inclined in the metal support body such that its opening on the back side is located downstream of the gas flow direction in the gas flow path compared to its opening on the front side. Along the gas flow direction in the aforementioned gas flow path, the first inclined through hole is located on the upstream side, and the second inclined through hole is located on its downstream side. The metal support is a single plate.

2. The metal support according to claim 1, wherein, The aforementioned inclined through hole is formed in the aforementioned metal support body such that the opening area on the front side is smaller than the opening area on the back side.

3. The metal support according to claim 1 or 2, wherein, The electrode layer has an insertion portion that is inserted into the inclined through hole.

4. An electrochemical element comprising a metal support as described in any one of claims 1 to 3, wherein an electrode layer, an electrolyte layer and a counter electrode layer are disposed on the aforementioned front side of the metal support.

5. The electrochemical element according to claim 4, wherein, At least a portion of the gas flow path through which the gas supplied to the aforementioned electrode layer flows is provided with a turbulence promoter that disrupts the flow within the gas flow path.

6. The electrochemical element according to claim 4 or 5, wherein, At least a portion of the gas flow path through which the gas supplied to the electrode layer is provided has a catalytic reaction section that reforms the fuel gas.

7. An electrochemical module configured in a manner comprising a plurality of electrochemical elements as described in any one of claims 4 to 6.

8. An electrochemical device comprising: an electrochemical element according to any one of claims 4 to 6 or an electrochemical module according to claim 7; and a fuel converter for supplying a gas containing a reducing component to the electrochemical element or the electrochemical module, or for converting the gas containing a reducing component generated in the electrochemical element or the electrochemical module.

9. An electrochemical device comprising: an electrochemical element according to any one of claims 4 to 6 or an electrochemical module according to claim 7; and a power converter that draws power from or supplies power to the electrochemical element or the electrochemical module.

10. An energy system comprising: the electrochemical device as claimed in claim 8 or 9; and a heat recovery utilization unit that reuses the heat discharged from the electrochemical device.

11. A solid oxide fuel cell comprising an electrochemical element according to any one of claims 4 to 6, wherein a power generation reaction occurs in the electrochemical element.

12. A solid oxide type electrolytic cell comprising any one of claims 4 to 6, wherein an electrolytic reaction occurs in the electrochemical element.

13. A method for manufacturing a metal support, wherein the method is for manufacturing the metal support according to any one of claims 1 to 3, wherein, For metal plates, multiple through holes are formed from the front side to the back side by any one of laser processing, punching or etching, or a combination thereof.

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