Electrochemical elements, electrochemical modules, solid oxide fuel cells, solid oxide electrolytic cells, electrochemical devices and energy systems

Abstract

To provide an electrochemical element capable of making the amount of gas flowing through a sub flow passage more uniform than before to improve the system efficiency.SOLUTION: An electrochemical element comprises: a plate-like base 10 which has an internal flow passage inside; a gas flowing allowing part which allows gas to pass through an internal flow passage A1 and the outside of the plate-like base 10; and electrochemical reaction parts 3a, 3b which comprise an electrode layer 31, a counter electrode layer 33, and an electrolyte layer 32 sandwiched between the electrode layer 31 and the counter electrode layer 33, and are formed on an outer surface of the plate-like base 10 by laminating the electrode layer 31, the electrolyte layer 32, and the counter electrode layer 33 in a state of covering the whole or a part of the gas flowing allowing part. The internal flow passage A1 has a plurality of sub flow passages A11 which extend in a first direction in a direction along a plate-like surface of the plate-like base 10 and are separate in a second direction crossing the first direction along the direction of the plate-like surface of the plate-like base 10, and the sub flow passages A11 are so constituted that gas flowing through the sub flow passages A11 has a pressure loss of 1 kPa or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to electrochemical elements, electrochemical modules, solid oxide fuel cells, solid oxide electrolytic cells, electrochemical devices, and energy systems. [Background technology]

[0002] Patent Document 1 proposes an electrochemical device, such as a fuel cell or electrolytic cell, that has a structure (electrochemical module) in which multiple electrochemical elements are stacked. The electrochemical element described in Patent Document 1 comprises a plate-shaped support with an internal channel formed on its inside, a gas flow-permeable section that allows gas to pass through from the internal channel to the outside of the support, and an electrochemical reaction section in which an electrode layer, an electrolyte layer, and a counter electrode layer are stacked on the support in that order. Furthermore, the internal channel of this electrochemical element has multiple subchannels that extend in a first direction along the plate-shaped surface of the plate-shaped support and are separated in a second direction that intersects the first direction along the plate-shaped surface. In the electrochemical element described in Patent Document 1, either a reducing component gas or an oxidizing component gas flows through the subchannels, and this gas is supplied to the electrode layer through the gas flow-permeable section.

[0003] According to the electrochemical element described in Patent Document 1, the rectifying effect caused by the gas flowing through multiple subchannels results in the gas velocity being approximately constant at any multiple points in a direction intersecting the gas flow direction. Therefore, in this electrochemical element, it can be expected that the amount of gas flowing through the electrochemical reaction section will be approximately constant. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-167130 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Incidentally, in the electrochemical element described in Patent Document 1, there is a risk that a difference in pressure loss of the gas flowing through the subchannels may occur between the subchannels due to errors during the manufacturing of the support equipped with the subchannels.

[0006] Furthermore, during the operation of the electrochemical apparatus, the temperature tends to be higher in the center of the support than at the edges. Therefore, there is a risk that the pressure loss of the gas flowing through the subchannels formed near the center and those formed near the edges may differ by about 5-10%.

[0007] In other words, in the electrochemical element described in Patent Document 1, there is a risk that differences in pressure loss of the gas flowing through the subchannels may occur between the subchannels, and there is room for improvement in terms of homogenizing the amount of gas flowing through each subchannel.

[0008] The present invention has been made in view of the above circumstances, and aims to provide an electrochemical element that can make the amount of gas flowing in the subchannel more uniform than conventional methods and improve system efficiency, an electrochemical module equipped with this electrochemical element, a solid oxide fuel cell, a solid oxide electrolytic cell, an electrochemical device, and an energy system. [Means for solving the problem]

[0009] The characteristic configuration of the electrochemical element according to the present invention for achieving the above objective is as follows: A plate-shaped support having an internal channel on the inside, The internal flow path and the gas flow-permeable portion that allows gas to pass through to the outside of the plate-shaped support, The electrochemical reaction section comprises an electrode layer, a counter electrode layer, and an electrolyte layer sandwiched between the electrode layer and the counter electrode layer, wherein the electrode layer, the electrolyte layer, and the counter electrode layer are laminated on the outer surface of the plate-shaped support such that they cover all or part of the gas flow-permitting portion, The internal channel has a plurality of subchannels that extend in a first direction along the plate-like surface of the plate-like support and are spaced apart in a second direction that intersects the first direction along the plate-like surface of the plate-like support. Within the sub-channel, the maximum area of ​​the cross-section perpendicular to the first direction is smaller than the maximum cross-sectional area of ​​the sub-channel, Gas flowing through the side channel A pressure loss increasing element is provided to increase pressure loss. The aforementioned sub-channel is divided into a plurality of continuous or discontinuous sub-channels by the pressure loss increasing body. The plurality of small channels extend in the first direction and are spaced apart in the second direction. The key feature is that the aforementioned sub-channel is configured such that the pressure loss of the gas flowing through it is 1 kPa or more.

[0010] According to the above characteristic configuration, By placing a pressure loss increasing element in the secondary channel and reducing the cross-sectional area of ​​the secondary channel at least partially, The pressure loss of the gas flowing through the subchannel is 1 kPa or more. It became, The difference in pressure loss between subchannels caused by manufacturing errors in the support and the temperature distribution of the support during operation is reduced to a level that is almost negligible. Furthermore, in addition to the pressure loss of the gas flowing through the secondary channel being 1 kPa or more, the formation of multiple continuous or discontinuous smaller channels within the secondary channel, along with the rectifying effect caused by the gas flowing through these smaller channels, makes it easier for the flow velocity to become constant at any multiple points in the secondary channel in a direction intersecting the gas flow direction. Therefore, the amount of gas flowing through multiple subchannels can be made more uniform than in the conventional method. In addition, it also suppresses localized unevenness in the amount of gas within the subchannel. Therefore, gas can be supplied uniformly over a wide area of ​​the electrochemical reaction section, creating a uniform reaction field. As a result, the reaction can proceed efficiently throughout the entire electrochemical element, improving system efficiency.

[0013] Further characteristic features of the electrochemical element according to the present invention are: The pressure loss increasing element is arranged in one or more configurations along the first direction and occupying 80% to 100% of the total length of the subflow channel.

[0014] By arranging pressure drop increasing elements, if extreme differences in flow resistance occur at any multiple points in the subchannel in a direction intersecting the gas flow direction, there is a risk that gas may not be supplied uniformly to the electrochemical reaction section. However, with the above-described configuration, the pressure drop increasing elements are arranged relatively uniformly in the first direction (i.e., the longitudinal direction of the subchannel). Therefore, differences in flow resistance are less likely to occur at any multiple points in the subchannel in a direction intersecting the gas flow direction, making it easier to supply gas uniformly to the electrochemical reaction section.

[0017] A further characteristic configuration of the electrochemical device according to the present invention is that the auxiliary flow path has at least one orifice portion.

[0018] According to the above characteristic configuration, by partially reducing the flow path cross-sectional area of the auxiliary flow path by the orifice portion, an auxiliary flow path in which the pressure loss of the gas flowing in the flow path is 1 kPa or more and 10 kPa or less can be realized.

[0019] A further characteristic configuration of the electrochemical device according to the present invention is that the plate-shaped support is composed of a metal member.

[0020] According to the above characteristic configuration, the electrochemical device has components of an electrochemical reaction part such as an electrode layer, an electrolyte layer, and a counter electrode layer formed on a plate-shaped support made of a metal member having excellent strength. Therefore, it is possible to thin and form the components of the electrochemical reaction part such as the electrode layer, the electrolyte layer, and the counter electrode layer into thin films. Therefore, it is possible to reduce the material cost of the electrochemical device while ensuring high performance and durability for the electrochemical device.

[0021] A characteristic configuration of the electrochemical module according to the present invention for achieving the above object is that the above electrochemical devices are arranged in a state where a plurality of them are assembled.

[0022] According to the above characteristic configuration, by arranging the electrochemical devices in a state where a plurality of them are assembled, it is possible to realize a compact, high-performance, and excellent-strength and reliable electrochemical module while suppressing the material cost and the processing cost. And, for example, when operating the electrochemical module as a fuel cell, it is also possible to obtain a large power generation output.

[0023] A characteristic configuration of the solid oxide fuel cell according to the present invention for achieving the above object is that it includes the above electrochemical device and causes a power generation reaction in the above electrochemical device.

[0024] According to the above characteristic configuration, a solid oxide fuel cell equipped with electrochemical elements that excel in strength (reliability), durability, and performance can perform power generation reactions, thereby enabling the creation of a highly reliable, highly durable, and high-performance solid oxide fuel cell.

[0025] The characteristic configuration of the solid oxide type electrolytic cell according to the present invention, for achieving the above objective, is: The key feature is that it includes the above-mentioned electrochemical element, and generates an electrolytic reaction in the electrochemical element.

[0026] According to the above characteristic configuration, a solid oxide type electrolytic cell equipped with electrochemical elements that excel in strength (reliability), durability, and performance can be used to generate gas through electrolytic reactions, thus enabling the production of a highly reliable, highly durable, and high-performance solid oxide type electrolytic cell.

[0027] The characteristic configuration of the electrochemical apparatus according to the present invention for achieving the above objective is: The above-mentioned electrochemical element or the above-mentioned electrochemical module, The present invention includes at least a fuel converter that generates a reducing component to be supplied to the electrochemical element or the electrochemical module, or a fuel converter that converts a gas containing a reducing component generated by the electrochemical element or the electrochemical module.

[0028] According to the above-described configuration, when an electrochemical element or electrochemical module is operated as a fuel cell, it can be configured to generate hydrogen using a fuel converter such as a reformer, based on natural gas supplied using existing raw material supply infrastructure such as city gas. This makes it possible to realize an electrochemical device equipped with an electrochemical element or electrochemical module that is highly durable, reliable, and high-performance. Furthermore, it becomes easier to construct a system for recycling unused fuel gas distributed from the electrochemical module, thus enabling the realization of a highly efficient electrochemical device. On the other hand, when an electrochemical element or electrochemical module is operated as an electrolytic cell, a gas containing water vapor or carbon dioxide is passed through the electrode layer, and a voltage is applied between the electrode layer and the counter electrode layer. In this case, electrons e are generated in the electrode layer. -Water (H2O) and carbon dioxide molecules (CO2) react with hydrogen (H2), carbon monoxide (CO), and oxygen ions (O). 2- This results in the generation of oxygen ions O 2- It moves through the electrolyte layer to the counter electrode layer. Then, in the counter electrode layer, oxygen ions O 2- The gas releases electrons to become oxygen (O2). Through the above reaction, if a gas containing water vapor is in circulation, water (H2O) is decomposed into hydrogen (H2) and oxygen (O2), and if a gas containing carbon dioxide molecules (CO2) is in circulation, it is electrolyzed into carbon monoxide (CO) and oxygen (O2). Therefore, when a 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 hydrogen and carbon monoxide generated by the electrolysis in an electrochemical element or electrochemical module. This makes it possible to circulate the hydrocarbons generated by the fuel converter to the electrochemical element or electrochemical module, or to extract them outside the system / device and use them separately as fuel or chemical raw materials.

[0029] The characteristic configuration of the electrochemical apparatus according to the present invention for achieving the above objective is: The above-mentioned electrochemical element or the above-mentioned electrochemical module, The key feature is that it includes at least a power converter that extracts power from the electrochemical element or the electrochemical module, or a power converter that supplies power to the electrochemical element or the electrochemical module.

[0030] According to the above characteristic configuration, the power converter can extract the power generated by the electrochemical element or electrochemical module, or supply power to the electrochemical element or electrochemical module. As a result, the electrochemical element or electrochemical module acts as a fuel cell or as an electrolytic cell. Therefore, according to the above characteristic configuration, an electrochemical device with improved efficiency in converting chemical energy such as fuel into electrical energy, or electrical energy into chemical energy such as fuel, can be realized. Furthermore, for example, when using an inverter as a power converter, it is preferable when operating as a fuel cell because the inverter can boost the voltage or convert DC to AC, making it easier to utilize the electrical output obtained from the electrochemical element or electrochemical module. Also, when operating as an electrolytic cell, it is preferable because an electrochemical device can be constructed that can obtain DC from an AC power source and supply DC power to the electrochemical element or electrochemical module.

[0031] The characteristic configuration of the energy system according to the present invention for achieving the above objective is: The above electrochemical apparatus and, The distinguishing feature is that it includes at least a waste heat utilization unit that reuses the heat discharged from the electrochemical apparatus.

[0032] According to the above-described configuration, an energy system with superior durability, reliability, and performance, as well as excellent energy efficiency, can be realized. Furthermore, it is possible to realize an energy-efficient hybrid system by combining it with a power generation system that utilizes the combustion heat of unused fuel gases emitted from electrochemical equipment. [Brief explanation of the drawing]

[0033] [Figure 1] This is a diagram illustrating the schematic configuration of an electrochemical element. [Figure 2] This is a bottom view showing an electrochemical element. [Figure 3] This is a cross-sectional view taken along line III-III in Figure 1. [Figure 4]This is a cross-sectional view taken along line IV-IV in Figure 1. [Figure 5] This is a VV cross-sectional view in Figure 1. [Figure 6] This is a cross-sectional view taken from VI-VI in Figure 1. [Figure 7] This is a cross-sectional view taken along line VII-VII in Figure 1. [Figure 8] This is a cross-sectional view taken from line VIII-VIII in Figure 1. [Figure 9] This is a cross-sectional view taken from line IX-IX in Figure 1. [Figure 10] This is a cross-sectional view of XX in Figure 1. [Figure 11] This is a cross-sectional view taken from line XI-XI in Figure 1. [Figure 12] This is a cross-sectional view from XII-XII in Figure 1. [Figure 13] This is a cross-sectional view from XIII-XIII in Figure 1. [Figure 14] This is a cross-sectional view from XIV-XIV in Figure 1. [Figure 15] This is a cross-sectional view taken along the line XV-XV in Figure 1. [Figure 16] This is a cross-sectional view taken from XVI-XVI in Figure 1. [Figure 17] This is a cross-sectional view taken from XVII-XVII in Figure 1. [Figure 18] This is a cross-sectional view from XVIII-XVIII in Figure 1. [Figure 19] This is a magnified view of the main part of an electrochemical element. [Figure 20] This is a magnified view of the main part of an electrochemical element. [Figure 21] This is a schematic diagram showing an electrochemical module. [Figure 22] This is a schematic diagram illustrating an energy system. [Figure 23] This is an enlarged view of the main part of an electrochemical element according to another embodiment. [Figure 24] This figure shows a schematic configuration of an electrochemical element according to another embodiment. [Figure 25] This is a bottom view of an electrochemical element according to another embodiment. [Figure 26] This is a bottom view of an electrochemical element according to another embodiment. [Figure 27] This is a cross-sectional view of section XXVII-XXVII in Figure 26. [Figure 28] This is a schematic diagram showing an energy system according to a different embodiment. [Modes for carrying out the invention]

[0034] Hereinafter, with reference to the drawings, an electrochemical element A, a solid oxide fuel cell (SOFC), an electrochemical module M, an electrochemical device 100, and an energy system Z according to embodiments of the present invention will be described.

[0035] Furthermore, when describing the relative positions of layers, for example, the side of the counter electrode layer relative to the electrolyte layer may be referred to as "up" or "upper side," and the side of the electrode layer as "down" or "lower side." Also, the stacking direction of the electrochemical element is defined as the +Z direction and the -Z direction (Z direction), the direction intersecting the Z direction is defined as the +X direction and the -X direction (X direction), and the direction intersecting the X direction and the Z direction is defined as the +Y direction and the -Y direction (Y direction). The XZ plane, the XY plane, and the YZ plane are generally orthogonal to each other.

[0036] (Electrochemical element) First, let's describe the electrochemical element A. As shown in Figures 1 to 20, the electrochemical element A comprises a plate-shaped support 10 consisting of a first plate-shaped body 1 made of a conductive material and a second plate-shaped body 2 also made of a conductive material, and two electrochemical reaction sections 3a and 3b formed on the plate-shaped support 10 at intervals. As will be described later, in this embodiment, the electrochemical element A is used as a solid oxide fuel cell (SOFC) that generates electricity by receiving a hydrogen-containing fuel gas and air.

[0037] (Plate-shaped support) Next, the plate-shaped support 10 will be described with reference to Figures 1 to 20. In this embodiment, the plate-shaped support 10 is rectangular in top view and is composed of a first plate-shaped body 1 and a second plate-shaped body 2, both of which are made of metal as conductive members. In other words, the plate-shaped support 10 is made of metal. The plate-shaped support 10 has an internal flow path A1 formed between the opposing surfaces of the first plate-shaped body 1 and the second plate-shaped body 2. Furthermore, the plate-shaped support 10 is provided with a first penetration portion 41 on one end in the longitudinal direction that forms a supply path 4 through which either the first gas or the second gas flows into the internal flow path A1 from the outside in the direction of surface penetration, and a second penetration portion 51 on the other end that forms a discharge path 5 through which the first gas that has flowed through the internal flow path A1 flows outward in the direction of surface penetration of the plate-shaped support 10.

[0038] Furthermore, as shown in Figures 4, 9 to 11, 17, and 18, a plate-shaped annular spacer 92 with a through hole extending from both sides is positioned between the first plate-shaped body 1 and the second plate-shaped body 2 on the plate-shaped support 10. This annular spacer 92 is positioned on one end side (first through-hole 41 side) and the other end side (second through-hole 51 side) of the plate-shaped support 10. In addition, the annular spacer 92, sandwiched between the first plate-shaped body 1 and the second plate-shaped body 2, has a flow path that allows gas to pass from the space inside the through hole to the space outside the annular spacer 92.

[0039] (First plate-like structure) The first plate-like body 1 supports the electrode layer 31, electrolyte layer 32, and counter electrode layer 33 that constitute the electrochemical reaction sections 3a and 3b, and plays a role in maintaining the strength of the electrochemical element A. As the material for the first plate-like body 1, a material with excellent electronic conductivity, heat resistance, oxidation resistance, and corrosion resistance is used. For example, ferritic stainless steel, austenitic stainless steel, nickel-based alloys, etc. are used, but are not limited to these. In particular, alloys containing chromium are preferably used. In this embodiment, the first plate-like body 1 uses an Fe-Cr alloy containing 18% to 25% by mass of Cr, but it is preferable to contain 0.05% or more by mass of Mn, and it is preferable to contain 0.05% to 1.0% by mass of Ni. Furthermore, the lower limit of Cu is preferably 0.01% by mass or more, more preferably 0.10% by mass or more, and even more preferably 0.20% by mass or more. The upper limit is preferably 1.0% by mass or less, more preferably 0.9% by mass or less, and even more preferably 0.8% by mass or less. Furthermore, the lower limit of Ti is preferably 0.05% by mass or more, more preferably 0.10% by mass or more, and even more preferably 0.15% by mass or more. The upper limit is preferably 1.0% by mass or less, more preferably 0.9% by mass or less, and even more preferably 0.8% by mass or less. By using such an Fe-Cr alloy, an alloy member with excellent performance, durability, and corrosion resistance can be used as the first plate-like body 1 while suppressing costs.

[0040] The first plate-like body 1 is plate-like overall. It has a gas flow-permitting section 1A which is provided with a large number of through holes 11 that penetrate through the front surface and the back surface (see Figures 7 to 10 and 14 to 19). In this embodiment, the gas flow-permitting section 1A is formed in the region where the electrochemical reaction sections 3a and 3b are formed, and the gas flow-permitting section 1A is not formed in the region where the electrochemical reaction sections 3a and 3b are not formed (the region between the two electrochemical reaction sections 3a and 3b). These through holes 11 can be provided in the first plate-like body 1 by, for example, mechanical, chemical, or optical drilling.

[0041] The through-hole 11 has the function of allowing gas to pass through from the back surface to the front surface of the first plate-like body 1. The gas flow-permeable portion 1A is preferably provided in a region smaller than the region where the electrode layer 31 is provided on the first plate-like body 1. Furthermore, to give the first plate-like body 1 gas permeability, it is also possible to use porous metals such as sintered metal or foamed metal.

[0042] As shown in Figure 19, a metal oxide layer 12 (metal oxide film) is provided on the surface of the first plate-like body 1 as a diffusion-inhibiting layer. That is, a diffusion-inhibiting layer is formed between the first plate-like body 1 and the electrode layer 31, which will be described later. The metal oxide layer 12 is provided not only on the surface of the first plate-like body 1 that is exposed to the outside, but also on the contact surface (interface) with the electrode layer 31. It can also be provided on the inner surface of the through hole 11. This metal oxide layer 12 can suppress elemental interdiffusion between the first plate-like body 1 and the electrode layer 31. For example, if ferritic stainless steel containing chromium is used as the first plate-like body 1, the metal oxide layer 12 will mainly consist of chromium oxide. The metal oxide layer 12, which is mainly composed of chromium oxide, suppresses the diffusion of chromium atoms, etc., from the first plate-like body 1 to the electrode layer 31 and the electrolyte layer 32. The thickness of the metal oxide layer 12 should be such that it is possible to achieve both high diffusion prevention performance and low electrical resistance.

[0043] The metal oxide layer 12 can be formed by various methods, but a preferred method is to oxidize the surface of the first plate-like body 1 to form a metal oxide. Alternatively, the metal oxide layer 12 may be formed on the surface of the first plate-like body 1 by spray coating methods (such as thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, and cold spray), PVD methods such as sputtering and PLD, or CVD, or by plating and oxidation treatment. Furthermore, the metal oxide layer 12 may contain a highly conductive spinel phase or the like.

[0044] When a ferritic stainless steel material is used as the first plate-like body 1, its coefficient of thermal expansion is close to that of materials such as YSZ (yttria-stabilized zirconia) and GDC (gadolinium-doped ceria, also called CGO), which are used for the electrode layer 31 and electrolyte layer 32, as described later. Therefore, the electrochemical element A is less likely to be damaged even when subjected to repeated low-temperature and high-temperature cycles. Thus, it is preferable because it is possible to realize an electrochemical element A with excellent long-term durability.

[0045] (Second plate-like structure) The second plate-like body 2 has a recess 2c formed therein, which becomes the internal flow channel A1, and is superimposed on the first plate-like body 1. The contact portion between the periphery of the second plate-like body 2 and the periphery of the first plate-like body 1 (hereinafter referred to as the peripheral edge 1a) is welded together (see Figures 3 to 18). In addition, other methods such as bonding or fitting can be used instead of welding for integration, and parts other than the peripheral edge 1a may be joined together as long as the internal flow channel A1 can be formed separately from the outside.

[0046] The second plate-like body 2 is made of a heat-resistant metal material. It is preferable that it be made of the same metal material as the first plate-like body 1, in order to reduce the difference in thermal expansion between it and the first plate-like body 1 and to ensure the reliability of joints such as welding.

[0047] Since the second plate-like body 2 is closely related to the configuration of the internal channel A1, the detailed configuration of the second plate-like body 2 will be described below in relation to the configuration of the internal channel A1.

[0048] (Configuration of the second plate-like body and internal channel) In this embodiment, the internal flow path A1 has a distribution section A12, a supply adjustment section A14, a supply buffer section A15, a plurality of sub-flow paths A11, a discharge buffer section A16, a discharge adjustment section A17, and a merging section A13, oriented in the direction of the flow of the first gas (i.e., from the +X direction to the -x direction). The internal flow path A1 has a symmetrical structure on the side where the first penetration section 41 is provided (supply path 4 side) and the side where the second penetration section 51 is provided (discharge path 5 side). Figures 3 to 10 show cross-sectional views of the supply path 4 side. Figures 11 to 18 show cross-sectional views of the discharge path 5 side.

[0049] The distribution section A12 is provided corresponding to each electrochemical element A. The distribution section A12 is located on the supply path 4 side and is a buffer section for supplying the first gas to each electrochemical element A. The distribution section A12 is located upstream of the multiple sub-channels A11 in the direction of first gas flow (X direction). Specifically, the distribution section A12 is formed by processing the second plate-like body 2 so that it is recessed downward in the stacking direction (-Z direction) compared to the peripheral edge 1a. As shown in Figures 1 and 20, the first through-hole 41 is located approximately in the center of the distribution section A12 in the direction of flow and its intersecting direction (Y direction). In other words, the through-hole of the first plate-like body 1 and the second plate-like body 2, which becomes the first through-hole 41, is formed at this position.

[0050] Furthermore, the distribution section A12 is elongated in the Y direction when viewed from above, as shown in Figure 1, etc. The length of the distribution section A12 in the Y direction corresponds to the length in the Y direction of the regions of the multiple subchannels A11, which are arranged parallel to each other at intervals in the Y direction and will be described later.

[0051] The multiple sub-channels A11 through which the first gas flows extend in a first direction (X direction) along the plate-like surface of the plate-like support 10, and are spaced apart in a second direction (Y direction) that intersects the first direction (X direction) along the plate-like surface of the plate-like support 10. Specifically, as shown in Figures 1 and 20, the multiple sub-channels A11 extend along the flow direction (X direction) from the vicinity of the supply adjustment unit A14 (described later) to the vicinity of the discharge adjustment unit A17. The multiple sub-channels A11 are arranged parallel to each other with spacing in the Y direction. As shown in Figures 1, 2, 7 to 10, the second plate-like body 2 has multiple sub-channel forming units 80 that form each of the multiple sub-channels A11, and multiple partition units 81 provided between adjacent sub-channel forming units 80 that separate each of the adjacent sub-channels A11. As shown in Figures 14 and 19, the sub-channel forming section 80 is formed in a concave shape with a bottom surface, and the upper surface of the partition section 81 is located above the bottom surface of the sub-channel forming section 80 in the stacking direction. In this embodiment, a metal mesh 7 is provided between the first plate-like body 1 and the second plate-like body 2, and the upper surface of the partition section 81 and the lower surface of the first plate-like body 1 abut against the mesh 7 in a mutually opposing state, with the mesh 7 sandwiched between the upper surface of the partition section 81 and the lower surface of the first plate-like body 1. Therefore, in this embodiment, the space between adjacent contact points between the partition section 81 and the mesh 7 becomes a sub-channel A11, and the first gas flows through each sub-channel A11 along the flow direction. Furthermore, by providing the mesh 7, the first gas flowing through the sub-channel A11 can be made to flow in a turbulent state. In this embodiment, the second plate-like body 2 is formed such that the partition portion 81, the distribution portion A12, the supply passage portion A14a of the supply adjustment portion A14, the supply buffer portion A15, the discharge buffer portion A16, the discharge passage portion A17a of the discharge adjustment portion 17, and the confluence portion A13 are all on the same plane, and the sub-flow channel forming portion 80 is formed to bulge downwards from these. Such a second plate-like body 2 can be manufactured by forming a metal plate by press working or the like.

[0052] In the present embodiment, as shown in FIG. 20, in the Y direction (a direction intersecting the flow-through direction), the length L3 of the partition portion 81 is smaller than the length L4 of the sub-channel forming portion 80 (L3 < L4). When L3 < L4, as shown in FIG. 19 and the like, the contact area between the upper surface of the partition portion 81 and the lower surface of the first plate-like body 1 can be reduced. That is, the space of the sub-channel A11 facing the first plate-like body 1 in which the gas flow allowance portion 1A is formed can be enlarged, and the amount of the first gas flowing from the sub-channel A11 toward the electrochemical reaction portions 3a and 3b can be increased.

[0053] Further, in the present embodiment, a pressure loss increasing body 6 is disposed in each sub-channel A11. By reducing the flow channel cross-sectional area of each sub-channel A11 formed by the sub-channel forming portion 80 with the pressure loss increasing body 6, the pressure loss of the first gas flowing through each sub-channel A11 (the pressure difference between the inlet and the outlet of each sub-channel A11) is increased compared to the case where the pressure loss increasing body 6 is not disposed. Specifically, the pressure loss of the first gas flowing through the sub-channel A11 when the pressure loss increasing body 6 is not disposed is approximately 0.01 kPa, whereas it is increased to approximately 2 kPa by disposing the pressure loss increasing body 6. The flow channel cross-sectional area of the sub-channel A11 is the area of the portion surrounded by the line segment connecting the tops of the two partition portions 81 adjacent to the upper surface of the sub-channel forming portion 80.

[0054] Thereby, in the present embodiment, the difference in pressure loss generated between the sub-channels A11 due to the processing error during the molding of the second plate-like body 2 or the temperature distribution of the first plate-like body 1 and the second plate-like body 2 when a power generation reaction or an electrolysis reaction occurs in the electrochemical element is relatively reduced to such an extent that it can be almost ignored. Therefore, the amount of the first gas flowing through the plurality of sub-channels A11 can be made more uniform than before, and the local shortage portions of the gas amount can be reduced. Thus, gas can be uniformly supplied over a wide area of the electrochemical reaction portions 3a and 3b to form a uniform reaction field.

[0055] Therefore, the pressure loss of the first gas in the sub-channel A11 needs to be 1 kPa or more, from the viewpoint of relatively reducing the difference in pressure loss between the sub-channels A11 to the point where it can be almost ignored. Furthermore, in order to relatively reduce the difference in pressure loss between the sub-channels A11 to the point where it can be more reliably ignored, the pressure loss of the first gas in the sub-channel A11 is preferably 3 kPa or more, and more preferably 5 kPa or more. In addition, if the pressure loss becomes too high, the energy utilization efficiency will decrease, so it is preferable that the pressure loss of the first gas in the sub-channel A11 be 10 kPa or less.

[0056] As shown in Figures 1, 14, 19, and 20, the pressure loss increasing body 6 in this embodiment is a cylindrical member whose length is approximately the same as the total length La of the sub-channel A11, and whose cross-sectional area perpendicular to the first direction is smaller than the cross-sectional area of ​​each sub-channel A11. Two pressure loss increasing bodies 6 are arranged in each sub-channel A11 with their longitudinal direction aligned with the first direction (X direction) and at predetermined intervals in the second direction, so that the pressure loss increasing bodies 6 occupy 80% to 100% of the total length La of each sub-channel A11. Furthermore, each pressure loss increasing body 6 is in contact with the lower surface of the mesh body 7 and the bottom surface of the sub-channel forming portion 80 in the second plate-like body 2, and is sandwiched between them. Therefore, in this embodiment, each sub-channel A11 is divided by the pressure loss increasing body 6 into three consecutive small channels A11a, A11b, and A11c that extend in the first direction and are separated in the second direction, and the cross-sectional area of ​​each sub-channel A11 is reduced by the cross-sectional integral of the pressure loss increasing body 6.

[0057] As described above, in the electrochemical element A of this embodiment, a pressure drop increasing body 6 is placed in each subchannel A11, and the cross-sectional area of ​​the channel is reduced so that the pressure drop of the first gas flowing through each subchannel A11 is 1 kPa or more. In addition, in the electrochemical element A, each subchannel A11 is divided into three consecutive small channels A11a, A11b, and A11c, and the flow straightening effect caused by the gas flowing through the small channels A11a, A11b, and A11c makes it easier for the flow velocity of the first gas to become constant at any multiple points in the direction (second direction) intersecting the first direction within the subchannel A11. Therefore, not only can the amount of first gas flowing through the multiple subchannels A11 be made uniform, but local biases in the amount of first gas within the subchannels A11 can also be suppressed, so that the first gas can be supplied uniformly over a wide area of ​​the electrochemical reaction section 3a, 3b to form a uniform reaction field, and the reaction can proceed efficiently throughout the entire electrochemical element A.

[0058] The pressure loss increasing body 6 is not limited in material, regardless of whether it is made of metal or resin, as long as it can increase the pressure loss in the subchannel A11. In this embodiment, the pressure loss increasing body 6 is made of metal. Therefore, a conductive path is formed in which the first plate-like body 1 and the second plate-like body 2 are electrically connected via the pressure loss increasing body 6 (and mesh-like body 7), which reduces the conductive resistance inside the electrochemical element A and realizes an electrochemical element A with higher performance.

[0059] As shown in Figures 1 and 6 to 10, the second plate-like body 2 has a supply adjustment section A14 between the distribution section A12 and the multiple sub-channels A11 in the direction along the flow direction (X direction). The supply adjustment section A14 temporarily stores the first gas in the distribution section A12 and restricts the supply of the first gas from the distribution section A12 to the multiple sub-channels A11.

[0060] The supply adjustment unit A14 has a plurality of supply passage sections A14a and a plurality of supply blocking sections A14b. The supply passage sections A14a allow the first gas to pass from the distribution unit A12 to the plurality of sub-channels A11. The supply blocking sections A14b prevent the first gas from passing from the distribution unit A12 to the plurality of sub-channels A11. As shown in Figure 6, the upper surface of the supply blocking section A14b is located above the upper surface of the supply passage section A14a in the stacking direction and is in contact with the lower surface of the first plate-like body 1. Therefore, the first gas in the distribution unit A12 is prevented from flowing in the flow direction by the supply blocking section A14b, while it flows in the flow direction through the supply passage section A14a and flows to the plurality of sub-channels A11.

[0061] In this embodiment, each supply blocking section A14b is formed in a generally rectangular shape, as shown in Figures 1 and 20, for example. Each rectangular supply blocking section A14b is arranged along the Y direction such that its longer side aligns with the Y direction. A supply passage section A14a is provided between adjacent supply blocking sections A14b. In other words, the supply passage section A14a is provided in the section where the shorter sides of adjacent supply blocking sections A14b face each other.

[0062] Furthermore, in the flow direction (X direction), one of the multiple partition sections 81 is positioned corresponding to the supply passage section A14a. Also, in the flow direction, at least one of the multiple sub-channels A11 is positioned corresponding to the supply blocking section A14b. Specifically, in this embodiment, two of the multiple supply blocking sections A14b are provided at positions corresponding to the +Y direction end and the -Y direction end of the distribution section A12, respectively.

[0063] Here, the first gas is guided from the distribution section A12 through the supply passage section A14a to the multiple sub-channels A11. According to the above configuration, since one of the partition sections 81 is positioned corresponding to the supply passage section A14a in the flow direction, the first gas pushed out from the distribution section A12 to the supply passage section A14a collides with the partition section 81 that protrudes upward in the stacking direction as it proceeds along the flow direction. Due to the collision with the partition section 81, the first gas proceeds in a direction that intersects with the flow direction. In other words, the first gas that has flowed from the distribution section A12 through the supply passage section A14a is not immediately introduced into the multiple sub-channels A11, but collides with the partition section 81 before reaching the sub-channels A11 and proceeds in a direction that intersects with the flow direction. Furthermore, the first gas that has proceeded in the direction that intersects with the flow direction is not returned to the distribution section A12 by the supply blocking section A14b that protrudes upward in the stacking direction, but is temporarily stored between the supply adjustment section A14 and the multiple sub-channels A11. Subsequently, the first gas is introduced into multiple sub-channels A11 formed by multiple sub-channel forming sections 80, following the extrusion from the distribution section A12. The supply buffer section A15 is the region where the first gas is temporarily stored between the supply adjustment section A14 and the multiple sub-channels A11.

[0064] Furthermore, in the flow direction, the supply blocking section A14b is provided corresponding to the first penetration section 41. This prevents the first gas introduced from the first penetration section 41 to the distribution section A12 from immediately flowing towards the multiple sub-flow channels A11. Therefore, the first gas can be temporarily stored in the distribution section A12.

[0065] As shown in FIG. 20, in the Y direction, the length L2 of the supply blocking portion A14b is greater than the length L1 of the supply passing portion A14a (L2 > L1). Also, the length L1 of the supply passing portion A14a is preferably smaller than the length L3 of the partition portion 81 (L1 < L3). Thereby, the first gas pushed out from the distribution portion A12 through the supply passing portion A14a can be made to collide with the end portion on the +X direction side of the partition portion 81, and can be temporarily stored in the supply buffer portion A15 described later. The relationship between L1 and L2 is determined by, for example, the amount of the first gas supplied to the distribution portion A12 per unit time, the amount of the first gas to be supplied to the plurality of sub-flow paths A11 per unit time, the number of the supply blocking portions A14b, the length L3 in the Y direction of the partition portion 81, the length L4 in the Y direction of the sub-flow path A11, and the like.

[0066] In addition, the number, arrangement, and shape of the supply blocking portion A14b and the supply passing portion A14a may be in any mode as long as these functions are exhibited.

[0067] As described above, the supply blocking section A14b of the supply adjustment section A14 is provided between the distribution section A12 and the multiple sub-channels A11, and acts as a barrier to the flow of first gas from the distribution section A12 to the multiple sub-channels A11. Therefore, the pressure loss of first gas when it flows from the distribution section A12 to the multiple sub-channels A11 is increased, and the first gas introduced into the distribution section A12 spreads throughout the distribution section A12 to fill it and is temporarily stored. As a result, the entire distribution section A12 becomes at a generally uniform pressure (equal pressure). In other words, the differential pressure between the distribution section A12 and each of the multiple sub-channels A11 becomes approximately the same. Furthermore, since first gas is supplied from the distribution section A12 to the multiple sub-channels A11 via the supply passage section A14a, the first gas is supplied to each sub-channel A11 at a generally equal pressure. As a result, the flow distribution of first gas (flow velocity, flow rate, and pressure, etc.) along the flow direction between each sub-channel A11 becomes generally uniform. Furthermore, the first gas flows from the distribution section A12 into multiple sub-channels A11. Due to the rectifying effect caused by this division into multiple channels, the flow distribution (flow velocity, flow rate, pressure, etc.) of the first gas becomes generally constant compared to when it flows through an internal channel without multiple channels. As a result, the difference between the areas where the first gas is insufficient and the areas where it is flowing in excess in the electrochemical reaction sections 3a and 3b is reduced, improving the utilization rate of the first gas throughout the entire electrochemical element A and thus improving the reaction efficiency of the electrochemical reaction.

[0068] Next, the confluence section A13 and the discharge adjustment section A17 will be described. The confluence section A13 and the discharge adjustment section A17 have the same configuration as the distribution section A12 and the supply adjustment section A14, respectively. In other words, the confluence section A13 is provided on the discharge passage 5 side and is a buffer section for discharging the first gas that has passed through the multiple sub-channels A11. The confluence section A13 is provided downstream of the multiple sub-channels A11 in the internal channel A1 in the direction of flow of the first gas. As shown in Figures 1 and 20, the second penetration section 51 is located approximately in the center of the confluence section A13 in the direction of flow and its intersecting direction. In other words, the through-holes of the first plate-like body 1 and the second plate-like body 2, which become the second penetration section 51, are formed at this position.

[0069] Furthermore, the confluence section A13 is elongated in the Y direction when viewed from above, as shown in Figure 1, etc. The Y-direction length of the confluence section A13 corresponds to the Y-direction length of the regions of the multiple subchannels A11 that are arranged parallel to each other at intervals in the Y direction.

[0070] As shown in Figures 1, 13, and 15-18, the second plate-like body 2 has a discharge adjustment section A17 between the multiple sub-channels A11 and the confluence section A13 in the direction along the flow direction (X direction). The discharge adjustment section A17 restricts the discharge of the first gas from the multiple sub-channels A11 to the confluence section A13.

[0071] The discharge adjustment section A17 has a plurality of discharge passage sections A17a and a plurality of discharge blocking sections A17b. The discharge passage sections A17a allow the first gas to pass from the plurality of sub-channels A11 to the confluence section A13. The discharge blocking sections A17b prevent the first gas from passing from the plurality of sub-channels A11 to the confluence section A13. As shown in Figure 13, the upper surface of the discharge blocking section A17b is located above the upper surface of the discharge passage section A17a in the stacking direction and is in contact with the lower surface of the first plate-like body 1. Therefore, the first gas in the plurality of sub-channels A11 is prevented from passing in the flow direction by the discharge blocking section A17b, while it passes in the flow direction through the discharge passage section A17a and flows to the confluence section A13.

[0072] In this embodiment, the discharge blocking section A17b, like the supply blocking section A14b, is formed in a generally rectangular shape, as shown in Figures 1 and 20, for example. Each rectangular discharge blocking section A17b is arranged along the Y direction, with its longer side aligned with the Y direction. A discharge passage section A17a is provided between adjacent discharge blocking sections A17b. In other words, the discharge passage section A17a is provided in the section where the shorter sides of adjacent discharge blocking sections A17b face each other.

[0073] In the flow direction, at least one of the multiple sub-channels A11 is positioned corresponding to the discharge blocking section A17b. Also in the flow direction, one of the multiple partition sections 81 is positioned corresponding to the discharge passing section A17a.

[0074] According to the above configuration, the first gas pushed out from the multiple sub-channels A11 collides with the discharge blocking section A17b, which protrudes upward in the stacking direction, as it travels along the flow direction. Due to the collision with the discharge blocking section A17b, the first gas travels in a direction intersecting the flow direction. In other words, the first gas that has traveled from the multiple sub-channels A11 is not immediately introduced into the confluence section A13, but collides with the discharge blocking section A17b before reaching the confluence section A13 and travels in a direction intersecting the flow direction. After that, the first gas travels along the pushout from the multiple sub-channels A11, passes through the discharge passage section A17a, and is introduced into the confluence section A13. The discharge buffer section A16 is a region where the first gas is temporarily stored between the multiple sub-channels A11 and the discharge adjustment section A17.

[0075] Furthermore, in the flow direction, the discharge blocking section A17b is provided corresponding to the second penetration section 51. This allows the first gas that has flowed through the multiple sub-channels A11 to be immediately introduced into the confluence section A13, preventing it from being discharged from the second penetration section 51. Thus, the first gas can be temporarily stored in the multiple sub-channels A11.

[0076] As shown in Figure 20, in the Y direction, the length L12 of the discharge blocking section A17b is greater than the length L11 of the discharge passing section A17a (L12 > L11). Furthermore, it is preferable that the length L12 of the discharge blocking section A17b is greater than the length L4 of the sub-channel forming section 80 (L12 > L3). This allows the first gas heading from the multiple sub-channels A11 towards the confluence section A13 to collide with the discharge blocking section A17b and be temporarily stored in the discharge buffer section A16 described later. The relationship between L11 and L12 is determined by, for example, the amount of first gas supplied to the multiple sub-channels A11 per unit time, the amount of first gas to be discharged from the confluence section A13 per unit time, the number of discharge blocking sections A17b, the length L3 of the partition section 81 in the Y direction, the length L4 of the sub-channels A11 in the Y direction, etc.

[0077] Furthermore, the number, arrangement, and shape of the discharge blocking section A17b and the discharge passing section A17a may be in any configuration as long as their functions are performed.

[0078] As described above, the discharge blocking section A17b of the discharge adjustment section A17 is provided between the multiple sub-channels A11 and the confluence section A13, and acts as a barrier to the flow of the first gas from the sub-channels A11 to the confluence section A13. Therefore, the pressure loss of the first gas when it flows from the multiple sub-channels A11 to the confluence section A13 is increased. As a result, the first gas introduced into the multiple sub-channels A11 is not immediately introduced into the confluence section A13, but spreads out to fill the multiple sub-channels A11. This makes it possible to make the flow distribution of the first gas (flow velocity, flow rate, pressure, etc.) along the flow direction between each sub-channel A11 generally uniform. In addition, because the first gas spreads out to fill the multiple sub-channels A11, electrochemical reactions can be carried out sufficiently within the multiple sub-channels A11. As a result, the reaction efficiency of the electrochemical reactions can be improved.

[0079] As shown in Figure 19, a metal oxide layer 2d (metal oxide film) is formed on the second plate-like body 2 in this embodiment. The metal oxide layer 2d can be formed by various methods, but a method of oxidizing the surface of the second plate-like body 2 to form a metal oxide is preferably used. Alternatively, it may be formed by the same method as the metal oxide layer 12 formed on the first plate-like body 1. Furthermore, similar to the metal oxide layer 12, it may also contain a highly conductive spinel phase or the like.

[0080] (Electrochemical reaction section) Next, the electrochemical reaction sections 3a and 3b will be described with reference to Figures 7 to 10 and 14 to 19. Note that the intermediate layer 34 and reaction prevention layer 35, which will be discussed later, are not shown in Figures 7 to 10 and 14 to 18.

[0081] (electrode layer) As shown in Figures 7 to 10 and 14 to 19, the electrode layer 31 can be provided as a thin layer on the front surface of the first plate-like body 1 in an area larger than the area where the through holes 11 are provided. When it is a thin layer, its thickness can be, for example, about 1 to 100 μm, preferably 5 to 50 μm. With such a thickness, it is possible to reduce the amount of expensive electrode layer material used and lower costs while ensuring sufficient electrode performance. Furthermore, the area of ​​the first plate-like body 1 where the through holes 11 are provided is entirely covered by the electrode layer 31. In other words, the through holes 11 are formed inside the area of ​​the first plate-like body 1 where the electrode layer 31 is formed. In other words, all the through holes 11 are provided facing the electrode layer 31.

[0082] Furthermore, the electrode layer 31 has multiple pores on its interior and surface to allow gas permeability. That is, the electrode layer 31 is formed as a porous layer. The electrode layer 31 is formed such that, for example, its density is 30% or more and less than 80%. The size of the pores can be appropriately selected to be suitable for smooth reaction during electrochemical reactions. Density is the ratio of the material constituting the layer to the surrounding space, and can be expressed as (1 - porosity), and is equivalent to relative density.

[0083] As the material for the electrode layer 31, composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2 can be used. In these examples, GDC, YSZ, and CeO2 can be called aggregates of the composite material. The electrode layer 31 is preferably formed by low-temperature firing (for example, a wet method using firing in a low temperature range without firing in a high temperature range higher than 1100°C), spray coating (such as thermal spraying, aerosol deposition, aerosol gas deposition, powder jet deposition, particle jet deposition, and cold spray), PVD (such as sputtering and pulsed laser deposition), or CVD. These processes, which can be used in a low temperature range, allow for the acquisition of a good electrode layer 31 without using firing in a high temperature range higher than 1100°C. Therefore, this method is preferable because it does not damage the first plate-like body 1 and suppresses elemental interdiffusion between the first plate-like body 1 and the electrode layer 31, thereby realizing an electrochemical element A with excellent durability. Furthermore, using a low-temperature firing method is even preferable because it simplifies the handling of the raw materials.

[0084] Furthermore, the electrode layer 31 may be configured such that the aggregate content, density, and strength of the cermet material continuously increase from the bottom to the top of the electrode layer 31. In this case, the electrode layer 31 does not need to have regions that can be clearly distinguished as layers. However, even in this case, it is possible to increase the aggregate content, density, strength, etc. of the cermet material in the portion adjacent to the electrolyte layer 32 (upper portion) of the electrode layer 31 compared to the portion adjacent to the first plate-like body 1 (lower portion).

[0085] (Middle class) The intermediate layer 34 can be formed as a thin layer on top of the electrode layer 31, covering the electrode layer 31. When forming a thin layer, its thickness can be, for example, about 1 to 100 μm, preferably about 2 to 50 μm, and more preferably about 4 to 25 μm. Such a thickness makes it possible to reduce the amount of expensive intermediate layer 34 material used, thereby lowering costs while ensuring sufficient performance. As the material for the intermediate layer 34, for example, YSZ (yttria-stabilized zirconia), SSZ (scandium-stabilized zirconia), GDC (gadolinium-doped ceria), YDC (yttrium-doped ceria), SDC (samarium-doped ceria), etc. Ceria-based ceramics are particularly preferred.

[0086] The intermediate layer 34 is preferably formed by the same method as the electrode layer 31. These film formation processes, which can be used in low-temperature ranges, allow the intermediate layer 34 to be obtained without using firing at high temperatures, for example, above 1100°C. Therefore, elemental interdiffusion between the first plate-like body 1 and the electrode layer 31 can be suppressed without damaging the first plate-like body 1, and a highly durable electrochemical element A can be realized. Furthermore, using a low-temperature firing method is even more preferable because it simplifies the handling of raw materials.

[0087] The intermediate layer 34 preferably has oxygen ion (oxide ion) conductivity, and more preferably has mixed conductivity of oxygen ions (oxide ions) and electrons. An intermediate layer 34 having these properties is suitable for application to electrochemical element A.

[0088] (electrolyte layer) As shown in Figures 7 to 10 and Figures 14 to 19, the electrolyte layer 32 is formed as a thin layer on top of the intermediate layer 34, covering the electrode layer 31 and the intermediate layer 34. It can also be formed as a thin film with a thickness of 10 μm or less. Specifically, the electrolyte layer 32 is provided across (straddles) the intermediate layer 34 and the first plate-like body 1. By configuring it in this way and bonding the electrolyte layer 32 to the first plate-like body 1, the electrochemical element A can be made to have excellent overall robustness.

[0089] Furthermore, as shown in Figures 7 and 14, the electrolyte layer 32 is provided on the front surface of the first plate-like body 1 in an area larger than the area where the through-holes 11 are provided. In other words, the through-holes 11 are formed inside the area of ​​the first plate-like body 1 where the electrolyte layer 32 is formed.

[0090] Furthermore, gas leakage from the electrode layer 31 and intermediate layer 34 can be suppressed around the electrolyte layer 32. To explain, when the electrochemical element A is used as a component of the SOFC, when the SOFC is in operation, gas is supplied to the electrode layer 31 from the back side of the first plate-like body 1 through the through hole 11. In the area where the electrolyte layer 32 is in contact with the first plate-like body 1, gas leakage can be suppressed without providing a separate component such as a gasket. In this embodiment, the electrolyte layer 32 completely covers the periphery of the electrode layer 31, but it is also possible to provide the electrolyte layer 32 on top of the electrode layer 31 and intermediate layer 34, and provide a gasket or the like around it.

[0091] As the material for the electrolyte layer 32, electrolyte materials that conduct oxygen ions such as 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), or electrolyte materials that conduct hydrogen ions such as perovskite-type oxides can be used. Zirconia-based ceramics are particularly preferred. If the electrolyte layer 32 is made of zirconia-based ceramics, the operating temperature of the SOFC using electrochemical element A can be made higher compared to ceria-based ceramics and various hydrogen ion conductive materials. For example, when using electrochemical element A in an SOFC, if the electrolyte layer 32 is made of a material such as YSZ that can exhibit high electrolyte performance even in high temperature ranges of around 650°C or higher, and the system is configured to use hydrocarbon-based raw materials such as city gas or LPG as the raw fuel, and to convert the raw fuel into the anode gas of the SOFC by steam reforming, then a highly efficient SOFC system can be constructed that uses the heat generated in the SOFC cell stack to reform the raw fuel gas.

[0092] The electrolyte layer 32 is preferably formed by the same method as the electrode layer 31. These film formation processes, which can be used in low-temperature ranges, allow for the production of a dense, airtight, and highly gas-barrier electrolyte layer 32 without using firing at high temperatures exceeding, for example, 1100°C. This suppresses damage to the first plate-like body 1 and inhibits elemental interdiffusion between the first plate-like body 1 and the electrode layer 31, enabling the realization of an electrochemical element A with excellent performance and durability. In particular, low-temperature firing methods and spray coating methods are preferable because they allow for the realization of low-cost elements. Furthermore, using a spray coating method is even more preferable because a dense, airtight, and highly gas-barrier electrolyte layer 32 can be easily obtained in low-temperature ranges.

[0093] The electrolyte layer 32 is densely constructed to shield against gas leaks of anode and cathode gases and to exhibit high ionic conductivity. The density of the electrolyte layer 32 is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. If the electrolyte layer 32 is a uniform layer, its density is preferably 95% or more, and more preferably 98% or more. Furthermore, if the electrolyte layer 32 is composed of multiple layers, it is preferable that at least a portion of it includes a layer with a density of 98% or more (a dense electrolyte layer), and more preferably a layer with a density of 99% or more (a dense electrolyte layer). This is because including such a dense electrolyte layer in part of the electrolyte layer 32 makes it easier to form a dense electrolyte layer 32 with high airtightness and gas barrier properties, even if the electrolyte layer 32 is composed of multiple layers.

[0094] (Reaction prevention layer) As shown in Figure 19, the reaction prevention layer 35 can be formed as a thin layer on the electrolyte layer 32. When forming a thin layer, its thickness can be, for example, about 1 to 100 μm, preferably about 2 to 50 μm, and more preferably about 3 to 15 μm. Such a thickness makes it possible to reduce the amount of expensive reaction prevention layer material used, thereby lowering costs while ensuring sufficient performance.

[0095] The reaction prevention layer 35 can be made of any material that can prevent the reaction between the components of the electrolyte layer 32 and the components of the counter electrode layer 33, such as ceria-based materials. Preferably, the reaction prevention layer 35 is made of a material containing at least one element selected from the group consisting of Sm, Gd, and Y. It is preferable that the material contains at least one element selected from the group consisting of Sm, Gd, and Y, and that the total content of these elements is between 1.0% by mass and 10% by mass. By introducing the reaction prevention layer 35 between the electrolyte layer 32 and the counter electrode layer 33, the reaction between the constituent materials of the counter electrode layer 33 and the constituent materials of the electrolyte layer 32 is effectively suppressed, improving the long-term stability of the performance of the electrochemical element A.

[0096] Forming the reaction prevention layer 35 using a method that can be performed at a processing temperature of 1100°C or lower is preferable because it suppresses damage to the first plate-like body 1 and inhibits elemental interdiffusion between the first plate-like body 1 and the electrode layer 31, thereby realizing an electrochemical element A with excellent performance and durability. For example, it can be carried out using a method similar to that used for forming the electrode layer 31. In particular, using a low-temperature firing method or a spray coating method is preferable because it can realize a low-cost element. Furthermore, using a low-temperature firing method is even preferable because it facilitates the handling of raw materials.

[0097] (Counter electrode layer) As shown in Figures 7 to 10 and Figures 14 to 19, the counter electrode layer 33 can be formed as a thin layer on the electrolyte layer 32 or the reaction prevention layer 35. When forming a thin layer, its thickness can be, for example, about 1 to 100 μm, preferably 5 to 50 μm. Such a thickness makes it possible to reduce the amount of expensive counter electrode layer material used, thereby lowering costs while ensuring sufficient electrode performance.

[0098] For example, composite oxides such as LSCF and LSM, ceria oxides, and mixtures thereof can be used as the material for the counter electrode layer 33. In particular, it is preferable that the counter electrode layer 33 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 33 constructed using the above material functions as a cathode.

[0099] Furthermore, it is preferable to form the counter electrode layer 33 using a method that can be performed at a processing temperature of 1100°C or lower, as this suppresses damage to the first plate-like body 1 and inhibits elemental interdiffusion between the first plate-like body 1 and the electrode layer 31, thereby realizing an electrochemical element A with excellent performance and durability. For example, it can be carried out using the same method as when forming the electrode layer 31. In particular, it is preferable to use a low-temperature firing method or a spray coating method as this can realize a low-cost element. Moreover, it is even preferable to use a low-temperature firing method as it facilitates the handling of raw materials.

[0100] (Solid Oxide Fuel Cell) By configuring the electrochemical reaction portions 3a and 3b as described above, when the electrochemical element A having the electrochemical reaction portions 3a and 3b functions as a fuel cell, the electrochemical element A can be used as a power generation cell of a solid oxide fuel cell. That is, a solid oxide fuel cell in which an electrochemical reaction occurs in the electrochemical element A can be realized.

[0101] For example, fuel gas containing hydrogen as the first gas is circulated through the through-hole 11 from the back surface of the first plate-like body 1 to the electrode layer 31, and air as the second gas is circulated to the counter electrode layer 3a serving as the counter electrode of the electrode layer 31, and maintained at an operating temperature of, for example, 500°C or higher and 900°C or lower. Then, when an electrolyte material that conducts oxygen ions is used for the electrolyte layer 32, oxygen O2 contained in the air reacts with electrons e - to form oxygen ions O 2- . The oxygen ions O 2- move through the electrolyte layer 32 to the electrode layer 31. In the electrode layer 31, hydrogen H2 contained in the circulated fuel gas reacts with oxygen ions O 2- to generate water H2O and electrons e - .

[0102] When an electrolyte material that conducts hydrogen ions is used for the electrolyte layer 32, hydrogen H2 contained in the fuel gas circulated in the electrode layer 31 releases electrons e - to generate hydrogen ions H + . The hydrogen ions H + move through the electrolyte layer 32 to the counter electrode layer 33. In the counter electrode layer 33, oxygen O2 contained in the air reacts with hydrogen ions H + and electrons e <a000014>to generate water H2O.

[0103] Due to the above reactions, an electromotive force is generated as an electrochemical output between the electrode layer 31 and the counter electrode layer 33. In this case, the electrode layer 31 functions as the fuel electrode (anode) of the fuel cell, and the counter electrode layer 33 functions as the air electrode (cathode).

[0104] Furthermore, a solid oxide fuel cell capable of operating at temperatures of 650°C or higher during rated operation is preferable because, in a fuel system using hydrocarbon gases such as city gas as the raw fuel, it is possible to construct a system in which the heat required to convert the raw fuel to hydrogen can be supplied by the waste heat of the fuel cell, thereby increasing the power generation efficiency of the fuel cell system. In addition, a solid oxide fuel cell operating at temperatures of 900°C or lower during rated operation is preferable because it enhances the suppression effect of Cr volatilization from the metal-supported electrochemical element A, and a solid oxide fuel cell operating at temperatures of 850°C or lower during rated operation is even more preferable because it further enhances the suppression effect of Cr volatilization.

[0105] (Electrochemical Module) Next, the electrochemical module M will be explained with reference to Figures 1 to 21.

[0106] As shown in Figure 21, the electrochemical module M comprises a housing B made of an insulator that houses a plurality of electrochemical elements A.

[0107] Multiple electrochemical elements A are stacked within the housing B in a configuration where a plate-shaped support 10 constituting one electrochemical element A faces another plate-shaped support 10 constituting another electrochemical element A, and the lower surface of the region forming the subchannel forming portion 80 of the second plate-shaped body 2 constituting one electrochemical element A is electrically connected to the counter electrode layers 33 of the electrochemical reaction portions 3a and 3b constituting another electrochemical element A. Furthermore, a flow section A2 is formed between the lower surface of the second plate-shaped body 2 constituting one electrochemical element A and the upper surface of the first plate-shaped body 1 constituting another electrochemical element A, through which the second gas flows along these two surfaces.

[0108] Furthermore, in the multiple electrochemical elements A, a first annular seal portion 42 is interposed between the lower surface of the region where the distribution portion A12 is formed in one electrochemical element A and the upper surface of the region where the first penetration portion 41 is formed in the first plate-like body 1 of another electrochemical element A, thereby separating the first penetration portion 41 from the flow portion A2 within the flow portion A2. Also, a second annular seal portion 52 is interposed between the lower surface of the region where the confluence portion A13 is formed in one electrochemical element A and the upper surface of the region where the second penetration portion 51 is formed in the first plate-like body 1 of another electrochemical element A, thereby separating the second penetration portion 51 from the flow portion A2 within the flow portion A2. As a result, a supply passage 4 is formed by the first penetration portion 41 and the first annular seal portion 42, and a discharge passage 5 is formed by the second penetration portion 51 and the second annular seal portion 52.

[0109] Furthermore, the first annular seal portion 42 and the second annular seal portion 52 are made of insulating ceramic material such as alumina, a metal coated therewith, or a material such as mica fiber or glass, and function as insulating seal portions that electrically insulate adjacent electrochemical elements A from each other.

[0110] Furthermore, multiple electrochemical elements A are housed within the housing B, sandwiched between a pair of current collectors 91 and 82. Output units 8, described later, extend from these current collectors 91 and 82 and are freely connected to a power supply destination outside the housing B to supply electrodes. The current collectors 91 and 82 are provided to hermetically house the multiple electrochemical elements A within the housing B and to function as buffers for each electrochemical element A.

[0111] Furthermore, in this embodiment, the electrochemical module M includes a first gas supply unit 61 that supplies a first gas to the internal flow path A1 from outside the housing B via a supply path 4, a first gas discharge unit 62 that discharges the first gas after the reaction, a second gas supply unit 71 that supplies a second gas to the flow section A2 from the outside, a second gas discharge unit 72 that discharges the second gas after the reaction, and an output unit 8 that obtains the output associated with the electrochemical reaction in the electrochemical reaction units 3a and 3b. The housing B also includes a distribution chamber 9 that distributes and supplies the second gas supplied from the second gas supply unit 71 to the flow section A2.

[0112] As a result, the electrochemical module M is supplied with fuel gas (sometimes called the first gas) from the first gas supply unit 61 and air (sometimes called the second gas) from the second gas supply unit 71, so that fuel gas enters as shown by the dashed arrows in Figure 21 and so on, and air enters as shown by the solid arrows.

[0113] The fuel gas supplied from the first gas supply unit 61 is guided to the supply path 4 through the first penetration portion 41 of the electrochemical element A located at the top, and flows through the supply path 4, which is partitioned by the first annular seal portion 42, to the internal flow path A1 of all the electrochemical elements A. The air supplied from the second gas supply unit 71 temporarily flows into the distribution chamber 9 and then flows through the flow section A2 formed between each electrochemical element A. In this embodiment, the direction in which the fuel gas flows through the internal flow path A1 along the plane of the plate-shaped support 10 is from the +X direction to the -X direction. Similarly, the direction in which the air flows through the flow section A2 along the plane of the plate-shaped support 10 is from the +X direction to the -X direction.

[0114] In some parts of Figure 21, etc., an electrochemical element A showing a cross-section including the internal flow path A1 and an electrochemical element A showing a cross-section including the flow passage A2 are conveniently shown side by side. The fuel gas supplied from the first gas supply unit 61 reaches the distribution unit A12 (see Figures 1, 4, 5, etc.), spreads out along the width direction on one end side via the distribution unit A12, and flows to each sub-flow path A11 of the internal flow path A1 (see Figures 1, 4, 5, etc.).

[0115] The fuel gas flows through the first gas supply section 61, the first annular seal section 42, the first penetration section 41, etc., and is supplied to the distribution section A12 of each electrochemical element A. The fuel gas supplied to the distribution section A12 is temporarily stored in the distribution section A12 by the supply adjustment section A14. Subsequently, the fuel gas is introduced from the distribution section A12 into a plurality of sub-channels A11. The fuel gas that enters each sub-channel A11 flows through the smaller channels A11a, A11b, and A11c which divide each sub-channel A11, and also enters the electrode layer 31 and electrolyte layer 32 via the gas flow permit section 1A. The fuel gas, along with the electrochemically reacted fuel gas, further proceeds through the sub-channels A11 (smaller channels A11a, A11b, A11c). The fuel gas that has reached the end of the flow direction of the multiple subflow channels A11 proceeds to the confluence section A13 with its flow partially restricted by the discharge adjustment section A17. The fuel gas that has proceeded to the confluence section A13 passes through the confluence section A13, the second penetration section 51, the second annular seal section 52, etc. Then, together with the electrochemically reacted fuel gas from other electrochemical elements A, it is discharged outside from the first gas discharge section 62.

[0116] Meanwhile, the air supplied from the second gas supply unit 71 enters the passage unit A2 via the distribution chamber 9 and can enter the counter electrode layer 33 and the electrolyte layer 32. The air, along with the air that has undergone electrochemical reaction, continues through the passage unit A2 along the electrochemical reaction units 3a and 3b and is discharged outside from the second gas discharge unit 72.

[0117] The electricity generated in the electrochemical reaction sections 3a and 3b in accordance with the flow of fuel gas and air is connected in series between the current collectors 91 and 82 by contact between the counter electrode layer 33 of the electrochemical reaction sections 3a and 3b of the adjacent electrochemical element A and the second plate-like body 2, and the combined output is taken out from the output section 8.

[0118] (Electrochemical apparatus and energy systems) Next, we will describe the electrochemical apparatus 100 and energy system Z constructed using the electrochemical module M described above.

[0119] Figure 22 shows an overview of the electrochemical apparatus 100 and the energy system Z. As shown in the figure, the energy system Z includes the electrochemical apparatus 100 and a heat exchanger 200 which serves as a waste heat utilization unit that reuses the heat circulating from the electrochemical apparatus 100.

[0120] In this embodiment, the electrochemical apparatus 100 includes an electrochemical module M, a fuel converter consisting of a desulfurizer 101 and a reformer 102, a fuel supply unit 103 that flows fuel gas containing reducing components generated by the fuel converter to the electrochemical module M, and an inverter 104, which is a type of power converter, as an output unit 8 that extracts power from the electrochemical module M.

[0121] More specifically, the electrochemical apparatus 100 includes a desulfurizer 101, a reformed water tank 105, a vaporizer 106, a reformer 102, a blower 107, a combustion unit 108, an inverter 104, a control unit 110, and an electrochemical module M.

[0122] The desulfurizer 101 removes (desulfurizes) sulfur compounds contained in hydrocarbon raw fuels such as city gas. When sulfur compounds are present in the raw fuel, the desulfurizer 101 can suppress adverse effects of sulfur compounds on the reformer 102 or electrochemical element A. The vaporizer 106 generates steam from the reformed water flowing from the reformed water tank 105. The reformer 102 uses the steam generated in the vaporizer 106 to steam reform the raw fuel that has been desulfurized in the desulfurizer 101, generating a reformed gas containing hydrogen.

[0123] The electrochemical module M generates electricity by using reformed gas flowing from the reformer 102 and air flowing from the blower 107 to perform an electrochemical reaction. The combustion unit 108 mixes the reaction exhaust gas flowing from the electrochemical module M with air and burns the combustible components in the reaction exhaust gas.

[0124] The inverter 104 adjusts the output power of the electrochemical module M to the same voltage and frequency as the power received from the commercial grid (not shown). The control unit 110 controls the operation of the electrochemical apparatus 100 and the energy system Z.

[0125] The reformer 102 uses the heat of combustion generated by the combustion of reaction exhaust gas in the combustion section 108 to perform a reforming treatment on the raw fuel.

[0126] The raw fuel is supplied to the desulfurizer 101 via the raw fuel supply line 112 by the operation of the booster pump 111. The reformed water from the reformed water tank 105 is supplied to the vaporizer 106 via the reformed water supply line 114 by the operation of the reformed water pump 113. The raw fuel supply line 112 then merges with the reformed water supply line 114 downstream of the desulfurizer 101, and the reformed water and raw fuel, which have merged outside the enclosure B, are supplied to the vaporizer 106.

[0127] The reformed water is vaporized into steam in the vaporizer 106. The raw fuel containing the steam generated in the vaporizer 106 is circulated to the reformer 102 through the steam-containing raw fuel supply line 115. In the reformer 102, the raw fuel is steam reformed, and a reformed gas (first gas with reducing properties) mainly composed of hydrogen gas is produced. The reformed gas produced in the reformer 102 is circulated to the electrochemical module M through the fuel supply unit 103.

[0128] The reaction exhaust gas is combusted in the combustion section 108 and becomes combustion exhaust gas, which is then sent to the heat exchanger 200 via the combustion exhaust gas discharge passage 116. A combustion catalyst section 117 (for example, a platinum-based catalyst) is located in the combustion exhaust gas discharge passage 116, where reducing components such as carbon monoxide and hydrogen contained in the combustion exhaust gas are burned and removed.

[0129] The heat exchanger 200 generates hot water by exchanging heat between the combustion exhaust gas produced by combustion in the combustion section 108 and the chilled water circulating through it. In other words, the heat exchanger 200 operates as a waste heat utilization unit that reuses the heat discharged from the electrochemical apparatus 100.

[0130] Alternatively, instead of a waste heat utilization section, a reaction exhaust gas utilization section may be provided that utilizes the reaction exhaust gas flowing (without being burned) from the electrochemical module M. Furthermore, at least a portion of the reaction exhaust gas flowing outside the housing B from the first gas discharge section 62 may be combined and recycled at any of the locations 100, 101, 103, 106, 112, 113, or 115 in Figure 22. The reaction exhaust gas contains residual hydrogen gas that was not used in the reaction at the electrochemical element A. In the reaction exhaust gas utilization section, the residual hydrogen gas is used for heat utilization through combustion or power generation using fuel cells, etc., thereby achieving efficient energy utilization.

[0131] [Another embodiment] [1] In the above embodiment, the pressure loss increasing body 6 is a cylindrical member, but it is not limited to this, and the pressure loss increasing body 6 can be of any shape as long as the pressure loss of the first gas flowing through the sub-channel A11 is a desired value of 1 kPa or more. For example, as shown in Figure 23, the pressure loss increasing body 6a may be a columnar member with a square cross-section in a direction perpendicular to the first direction, the pressure loss increasing body 6b may be a columnar member with a T-shaped cross-section, or the pressure loss increasing body 6c may be a columnar member that fills the bottom side of the sub-channel forming part 80 (the lower side of the sub-channel A11), and it does not have to be a columnar member, but may be a cubic member. Note that, as shown in Figure 23, when the pressure loss increasing bodies 6a and 6b are adopted, the sub-channel A11 is divided into two small channels and the cross-sectional area of ​​the sub-channel A11 is reduced, thereby increasing the pressure loss, and when the pressure loss increasing body 6c is adopted, the pressure loss is increased simply by reducing the cross-sectional area of ​​the sub-channel A11. Furthermore, the pressure loss increasing body may have different cross-sectional areas perpendicular to the first direction, and may be, for example, a conical, biconical, or irregularly shaped member. Note that if the sub-channel is blocked by the pressure loss increasing body, the first gas will not flow. Therefore, if the mesh body 7 is not provided and the upper surface of the partition 81 and the lower surface of the first plate-like body 1 are in contact, the maximum cross-sectional area of ​​the pressure loss increasing body perpendicular to the first direction must be smaller than the maximum cross-sectional area of ​​the sub-channel.

[0132] [2] In the above embodiment, two pressure loss increasing bodies 6 having a length approximately the same as the total length La of the sub-channel A11 are used to divide the sub-channel A11 into three consecutive small channels A11a, A11b, and A11c. However, the embodiment is not limited to this, and any embodiment is acceptable as long as the pressure loss of the first gas flowing through the sub-channel A11 is a desired value of 1 kPa or more. For example, the sub-channel A11 may be divided into two or four or more small channels. Alternatively, as shown in Figure 24, a plurality of cylindrical pressure loss increasing bodies 6d may be intermittently arranged in the sub-channel A11 along the first direction (X direction), forming two intermittent small channels through which the first gas mainly flows along the first direction. Furthermore, it is not necessary for the pressure loss increasing bodies 6 to occupy 80% to 100% of the total length La of the sub-channel A11. As shown in Figure 24, a plurality of pressure loss increasing bodies 6 may occupy less than 80% of the total length La of the sub-channel A11.

[0133] [3] In the above embodiment, a mesh-like structure 7 is provided, but the embodiment is not limited to this, and a configuration without a mesh-like structure 7 is also possible.

[0134] [4] In the above embodiment, the pressure loss increasing body 6 is arranged in the sub-channel A11 to make the pressure loss of the first gas flowing through the sub-channel A11 1 kPa or more. However, the embodiment is not limited to this, and at least one orifice section may be provided in the sub-channel to make the pressure loss of the first gas flowing through the sub-channel 1 kPa or more. That is, as shown in Figure 25, an orifice section R may be formed at an intermediate position in each sub-channel A11 to reduce the flow cross-sectional area of ​​the sub-channel A11, thereby partially reducing the flow cross-sectional area of ​​the sub-channel A11 and making the pressure loss of the first gas flowing through the sub-channel A11 1 kPa or more. In addition, multiple orifice sections R may be provided in each sub-channel A11, and the number of orifice sections R may differ for each sub-channel A11. For example, as shown in Figure 26, the orifice sections R may be arranged in a staggered pattern. Furthermore, if an orifice section R is provided, it is preferable to provide a mesh body 7 or the like to ensure a flow path for the first gas between the orifice section R and the first plate-like body 1. Alternatively, a pressure loss increasing body and an orifice section may be combined to increase the pressure loss in the sub-flow path A11 to a desired value.

[0135] [5] In the above embodiment, metal oxide layers 12 and 2d are formed on the front and back surfaces of the first plate-like body 1 and the second plate-like body 2, but the embodiment is not limited to this, and may be an embodiment in which metal oxide layers 12 and 2d are not formed.

[0136] [6] In the above embodiment, the electrochemical element A was used in a solid oxide fuel cell, but this electrochemical element A can also be used in a solid oxide electrolytic cell or an oxygen sensor using solid oxides. When the electrochemical element A is operated as an electrolytic cell, a gas containing water vapor or carbon dioxide is passed through the electrode layer 31, and a voltage is applied between the electrode layer 31 and the counter electrode layer 33. This generates electrons e in the electrode layer 31. - It reacts with water molecules H2O and carbon dioxide molecules CO2, producing hydrogen molecules H2, carbon monoxide CO, and oxygen ions O 2- This is the result. Oxygen ion O 2- It moves through the electrolyte layer 32 to the counter electrode layer 33. Then, in the counter electrode layer 33, oxygen ions O2- The electrons are released to form oxygen molecules (O2). Through the above reaction, water molecules (H2O) are electrolyzed into hydrogen (H2) and oxygen (O2), and if a gas containing carbon dioxide molecules (CO2) is passed through, it is electrolyzed into carbon monoxide (CO) and oxygen (O2). Figure 28 shows an example of an energy system Z and electrochemical apparatus 100 when the electrochemical reaction sections 3a and 3b of the electrochemical element A are operated as electrolytic cells that generate gases by electrolytic reactions. In this system, supplied water and carbon dioxide are electrolyzed in the electrochemical reaction sections 3a and 3b to produce hydrogen and carbon monoxide, etc. Furthermore, hydrocarbons, etc., are synthesized in the fuel converter 25. Energy efficiency can be increased by configuring the heat exchanger 24 in Figure 28 to operate as a waste heat utilization section that heats and vaporizes water by reusing the reaction heat generated by the reaction occurring in the fuel converter 25, and the heat exchanger 23 in the same figure to operate as a waste heat utilization section that preheats water vapor and carbon dioxide by reusing the waste heat generated by the electrochemical element A. Therefore, according to the above configuration, an electrochemical apparatus 100 and an energy system can be realized that can improve the efficiency of converting electrical energy into chemical energy such as fuel.

[0137] [7] In the above embodiment, multiple electrochemical elements A are used in combination as an electrochemical module M, but the embodiment is not limited to this, and it is also possible to use them individually.

[0138] [8] In the above embodiment, composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2 are used as the material for the electrode layer 31, and composite oxides such as LSCF and LSM are used as the material for the counter electrode layer 33, and hydrogen gas is flowed through the electrode layer 31 to make it a fuel electrode (anode), and air is flowed through the counter electrode layer 33 to make it an air electrode (cathode), and it is used as a solid oxide fuel cell, but it is not limited to this. The electrochemical element A may be configured in such a way that the electrode layer 31 is an air electrode and the counter electrode layer 33 is a fuel electrode by changing this configuration. Specifically, composite oxides such as LSCF and LSM are used as the material for the electrode layer 31, and composite materials such as NiO-GDC, Ni-GDC, NiO-YSZ, Ni-YSZ, CuO-CeO2, and Cu-CeO2 are used as the material for the counter electrode layer 33. With an electrochemical element A configured in this way, air is circulated through the electrode layer 31 to form an air electrode, and hydrogen gas is circulated through the counter electrode layer 33 to form a fuel electrode, and the electrochemical element A can be used as a solid oxide fuel cell.

[0139] [9] In the above embodiment, the electrode layer 31 is placed between the first plate-like body 1 and the electrolyte layer 32, and the counter electrode layer 33 is placed on the side opposite to the first plate-like body 1 when viewed from the electrolyte layer 32. However, the embodiment is not limited to this, and the electrode layer 31 and the counter electrode layer 33 may be placed in reverse. In other words, it is also possible to place the counter electrode layer 33 between the first plate-like body 1 and the electrolyte layer 32, and place the electrode layer 31 on the side opposite to the first plate-like body 1 when viewed from the electrolyte layer 32. In this case, the flow of gas to the electrochemical element A also needs to be changed. In other words, regarding the order of the electrode layer 31 and the counter electrode layer 33, and whether the first gas or the second gas is a reducing component gas or an oxidizing component gas, various configurations can be adopted as long as they are arranged so that the first gas and the second gas flow in a manner that allows them to react appropriately with the electrode layer 31 and the counter electrode layer 33.

[0140]

[10] In the above embodiment, the electrochemical reaction sections 3a and 3b are provided on the side of the first plate-like body 1 opposite to the second plate-like body 2 so as to cover the gas flow-permitting section 1A. However, the embodiment is not limited to this, and may be provided on the side of the first plate-like body 1 that is opposite to the second plate-like body 2. That is, the electrochemical reaction sections 3a and 3b may be arranged in the internal flow path A1.

[0141]

[11] In the above embodiment, the first through-hole 41 and the second through-hole 51 are provided as a pair at both ends of the rectangular plate-shaped support 10, but the embodiment is not limited to this. The first through-hole 41 and the second through-hole 51 may be provided at positions other than both ends, or two or more pairs may be provided. Also, the first through-hole 41 and the second through-hole 51 do not need to be provided as a pair. Therefore, one or more first through-hole 41 and second through-hole 51 can be provided.

[0142]

[12] In the above embodiment, the plate-shaped support 10 is rectangular in shape, but it is not limited to this. The plate-shaped support 10 can take various forms, such as square or circular shapes.

[0143]

[13] In the above embodiment, the shape of the first and second annular sealing portions 42 and 52 is not limited as long as they are configured to prevent gas leakage by connecting the first and second through portions 41 and 51 to each other. In other words, the first and second annular sealing portions 42 and 52 should be endless in shape with an opening inside that communicates with the through portion, and should be configured to seal between adjacent electrochemical elements A. The first and second annular sealing portions 42 and 52 are, for example, annular. The annular shape can be any shape, such as circular, elliptical, square, polygonal, etc.

[0144]

[14] In the above embodiment, an internal flow path A1 is formed by the first plate-like body 1 and the second plate-like body 2, and the internal flow path A1 has a distribution section A12, a supply adjustment section A14, a supply buffer section A15, a plurality of sub-flow paths A11, a discharge buffer section A16, a discharge adjustment section A17 and a merging section A13, but it is not limited to this. For example, the internal flow path A1 may have a distribution section A12, a plurality of sub-flow paths A11 and a merging section A13.

[0145]

[15] In the above embodiment, the entire region in the second plate-like body 2 where the multiple subchannels A11 are formed is formed in a corrugated shape, but the embodiment is not limited to this, and a part of it may be formed in a corrugated shape.

[0146] The configurations disclosed in the above embodiments (including other embodiments) can be applied in combination with configurations disclosed in other embodiments, provided that no inconsistencies arise. Furthermore, the embodiments disclosed herein are illustrative, and the embodiments of the present invention are not limited thereto and can be modified as appropriate without departing from the object of the present invention. [Industrial applicability]

[0147] The present invention can be used as an electrochemical element, electrochemical module, solid oxide fuel cell, solid oxide electrolytic cell, electrochemical device, and energy system. [Explanation of symbols]

[0148] 1: First plate-like body (support) 1A: Gas flow permitted section 2: Second plate-like body 2c: recess 2d: Metal oxide layer (metal oxide film) 3a, 3b: Electrochemical reaction section 4: Supply route 5:Exhaust channel 6: Pressure loss increasing element 6a, 6b, 6c, 6d: Pressure drop increasing body 7: Reticular 8: Output section 9: Distribution room 10: Plate-shaped support 12: Metal oxide layer (metal oxide film) 31: Electrode layer 32: Electrolyte layer 33: Counter electrode layer 41:First penetration part 42: First ring seal section 51:Second penetration part 52: Second annular seal section 61: First Gas Supply Department 71: Second Gas Supply Department 80: Sub-channel forming part 81: Partition section 100: Electrochemical apparatus 102: Modifier 103:Fuel supply section 104: Inverter A: Electrochemical element A1: Internal flow path A11: Sub-channel A12:Distribution section A13: Merging section A14: Supply adjustment section A14a: Supply passage section A14b: Supply blocking part A15: Supply buffer section A16: Discharge buffer section A17: Discharge adjustment section A17a: Discharge passage section A17b: Discharge prevention part A2: Flow section B: Cabinet M: Electrochemical module R: Orifice section Z: Energy System

Claims

1. A plate-shaped support having an internal channel on the inside, The internal flow path and the gas flow-permeable portion that allows gas to pass through to the outside of the plate-shaped support, The device comprises an electrode layer, a counter electrode layer, and an electrolyte layer sandwiched between the electrode layer and the counter electrode layer. The plate-shaped support comprises an electrochemical reaction section formed by laminating the electrode layer, the electrolyte layer, and the counter electrode layer on the outer surface of the plate-shaped support such that they cover all or part of the gas flow-permitting portion, The internal channel has a plurality of subchannels that extend in a first direction along the plate-like surface of the plate-like support and are spaced apart in a second direction that intersects the first direction along the plate-like surface of the plate-like support. Within the sub-channel, a pressure loss increasing body is provided, the maximum area of ​​the cross-section perpendicular to the first direction being smaller than the maximum cross-sectional area of ​​the sub-channel, thereby increasing the pressure loss of the gas flowing through the sub-channel. The aforementioned sub-channel is divided into a plurality of continuous or discontinuous sub-channels by the pressure loss increasing body. The plurality of small channels extend in the first direction and are spaced apart in the second direction. An electrochemical element in which the aforementioned subchannel is configured such that the pressure loss of the gas flowing through the subchannel is 1 kPa or more.

2. The electrochemical element according to claim 1, wherein one or more pressure drop increasing members are arranged along the first direction and occupy 80% to 100% of the total length of the subflow channel.

3. The electrochemical element according to claim 1 or 2, wherein the subchannel has at least one orifice portion.

4. The electrochemical element according to any one of claims 1 to 3, wherein the plate-shaped support is made of a metal member.

5. An electrochemical module in which a plurality of electrochemical elements according to any one of claims 1 to 4 are arranged in an assembled state.

6. A solid oxide fuel cell comprising an electrochemical element according to any one of claims 1 to 4, wherein the electrochemical element generates an electricity reaction.

7. A solid oxide type electrolytic cell comprising an electrochemical element according to any one of claims 1 to 4, wherein an electrolytic reaction is generated in the electrochemical element.

8. An electrochemical element according to any one of claims 1 to 4 or an electrochemical module according to claim 5, An electrochemical apparatus comprising at least a fuel converter that generates a reducing component to be supplied to the electrochemical element or the electrochemical module, or a fuel converter that converts a gas containing a reducing component generated by the electrochemical element or the electrochemical module.

9. An electrochemical element according to any one of claims 1 to 4 or an electrochemical module according to claim 5, An electrochemical apparatus comprising at least a power converter that extracts power from the electrochemical element or the electrochemical module, or that supplies power to the electrochemical element or the electrochemical module.

10. An energy system comprising at least an electrochemical apparatus according to claim 8 or 9, and a waste heat utilization unit for reusing heat discharged from the electrochemical apparatus.

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