Electrochemical cell stacks and electrochemical apparatus

Abstract

This suppresses gas leakage from the electrochemical cell stack. [Solution] The electrochemical cell stack comprises a laminate containing a plurality of electrochemical cells, a first clamping plate provided in contact with the laminate, and a heat conductive member provided in contact with the first clamping plate. Within the operating temperature range of the electrochemical cell stack, the thermal conductivity of the heat conductive member is lower than that of the first clamping plate.

Description

Technical Field

[0001] Embodiments of the present invention relate to an electrochemical stack and an electrochemical device.

Background Art

[0002] Electrochemical cells such as solid oxide type electrochemical cells have been developed as fuel cells for power generation, electrolyzers for hydrogen production, and power storage systems combining these. Since solid oxide type electrochemical cells use solid oxides as electrolytes, for example, they can be operated at a high operating temperature of 600°C or higher and 1000°C or lower, and a large reaction rate can be obtained without using expensive noble metal catalysts. Therefore, when this is operated as a solid oxide fuel cell (SOFC), high power generation efficiency can be obtained, and when it is operated as a solid oxide electrolysis cell (SOEC), hydrogen can be produced efficiently at a low electrolysis voltage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem to be solved by the present invention is to suppress gas leakage from the electrochemical stack.

Means for Solving the Problems

[0005] The electrochemical stack of the embodiment includes a laminate including a plurality of electrochemical cells, a first clamping plate provided in contact with the laminate, and a heat conduction member provided in contact with the first clamping plate. In the operating temperature range of the electrochemical stack, the thermal conductivity of the heat conduction member is lower than the thermal conductivity of the first clamping plate.

Brief Description of the Drawings

[0006] [Figure 1] This is a schematic diagram showing an example of the structure of an electrochemical cell stack. [Figure 2] This is a schematic diagram showing an example of a laminated structure. [Figure 3] This is a schematic diagram to explain thermal deformation. [Figure 4] This is a schematic diagram illustrating the first embodiment of the electrolytic device. [Figure 5] This is a schematic diagram illustrating a second embodiment of the electrolytic device. [Figure 6] This is a schematic diagram showing an example of the structure of an electrolytic device. [Figure 7] This is a schematic diagram illustrating a third embodiment of the electrolytic device. [Figure 8] This is a schematic diagram showing the planar shape of the sealing member. [Figure 9] This is a schematic diagram showing a modified example of the third embodiment. [Figure 10] This is a schematic diagram showing a modified example of the third embodiment. [Figure 11] This is a schematic diagram illustrating a fourth embodiment of the electrolytic device. [Modes for carrying out the invention]

[0007] The embodiments will be described below with reference to the drawings. In each of the embodiments shown below, substantially identical components are denoted by the same reference numerals, and their descriptions may be partially omitted. The drawings are schematic, and the relationship between thickness and planar dimensions, the ratio of the thickness of each part, etc., may differ from those in reality.

[0008] In this specification, unless otherwise specified, "connect" may include not only direct connections but also indirect connections.

[0009] (Example of an electrolytic device structure) Figure 1 is a schematic diagram showing an example of an electrochemical cell stack in an electrolytic apparatus, specifically an example of an electrochemical cell stack structure in an electrolytic apparatus. Figure 1 is a schematic diagram showing an example of an electrolytic cell stack structure 10.

[0010] The electrolytic cell stack 10 performs an electrolytic reaction using a gas supplied from outside the electrolytic cell stack 10 (supply gas) and can discharge the gas produced by the electrolytic reaction (generated gas). The supply gas is supplied from a gas supply source outside the electrolytic cell stack 10 and contains, for example, water vapor, carbon dioxide gas, and hydrogen gas. The generated gas contains, for example, carbon monoxide gas and hydrogen gas. The electrolytic cell stack 10 has a laminate 1, a lower clamping plate 2, and an upper clamping plate 3.

[0011] The laminate 1 is a solid oxide type electrochemical stack having a solid oxide type electrochemical cell 11. The laminate 1 is provided between a lower clamping plate 2 and an upper clamping plate 3. The lower clamping plate 2 is provided, for example, at the lower end of the laminate 1. The upper clamping plate 3 is provided, for example, at the upper end of the laminate 1. The lower clamping plate 2 and the upper clamping plate 3 are, for example, metal plates. The metal plates are conductors. Examples of metal plates include stainless steel (SUS) and nickel (Ni) alloys.

[0012] Figure 2 is a schematic diagram showing an example of the structure of the laminate 1. The laminate 1 has solid oxide electrochemical cells 11. Figure 2 shows a planar stack having a plurality of solid oxide electrochemical cells 11. The laminate 1 is not limited to a planar stack, and may be, for example, a cylindrical stack. The solid oxide electrochemical cells 11 are planar electrochemical cells and fuel electrode-supported cells. The solid oxide electrochemical cells 11 are connected to a power source that can supply voltage or current for carrying out electrolytic reactions, for example.

[0013] The solid oxide type electrochemical cell 11 can be operated at high temperatures, and the electrolysis reaction is carried out, for example, at a temperature of 600°C or higher and 1000°C or lower. The solid oxide type electrochemical cell 11 may be provided, for example, in a heater, and the temperature may be adjusted by a heater that heats the solid oxide type electrochemical cell 11. The solid oxide type electrochemical cell 11 may be provided in an electric furnace that can control the temperature of the solid oxide type electrochemical cell 11.

[0014] A plurality of solid oxide type electrochemical cells 11 are stacked in order. The solid oxide type electrochemical cell 11 includes an air electrode 101, an electrolyte 102, a fuel electrode 103, and a support 104.

[0015] The electrolysis reaction by the electrolysis cell stack 10 is carried out, for example, as follows. Gases such as carbon dioxide gas, water vapor, and hydrogen gas are supplied to the fuel electrode 103 side. By the electrolysis reaction at the fuel electrode 103, for example, hydrogen gas can be generated from water vapor, and carbon monoxide gas can be generated from carbon dioxide gas. Gases such as carbon dioxide gas, water vapor, hydrogen gas, and carbon monoxide gas are discharged from the fuel electrode 103 side.

[0016] Gases such as air are supplied to the air electrode 101 side. The air is supplied, for example, to purge oxygen generated during electrolysis. Oxygen can be generated by the electrolysis reaction at the air electrode 101. Air having an oxygen concentration higher than the oxygen concentration in the atmosphere is discharged from the air electrode 101 side.

[0017] The air electrode 101 has, for example, a porous electric conductor. Examples of the porous electric conductor include perovskite type oxides and the like.

[0018] The air electrode 101 further has, for example, a catalyst that promotes the electrolysis reaction contained in the product gas. The catalyst contains, for example, at least one element of platinum (Pt), ruthenium (Ru), cerium (Ce), lanthanum (La), cobalt (Co), nickel (Ni), aluminum (Al), and copper (Cu). The catalyst is supported, for example, on the surface of the electric conductor. The catalyst may form a catalyst layer provided on the surface of the electric conductor.

[0019] The electrolyte 102 has, for example, an ion conductor that does not conduct electricity. Examples of ion conductors include solid oxides such as stabilized zirconia, perovskite-type oxides, and molded ceria-based solid solutions.

[0020] The fuel electrode 103 has, for example, a porous electrical conductor. Examples of porous electrical conductors include mixed sintered bodies of metal and solid oxides (cermets). Examples of mixed sintered bodies include yttria-stabilized zirconia and scandia-stabilized zirconia.

[0021] The electrolytic cell stack 10 can isolate the atmospheres of adjacent solid oxide electrochemical cells 11, for example, by a separator 121. Furthermore, the atmospheres of the fuel electrode 103 and air electrode 101 of the same solid oxide electrochemical cell 11 can be isolated by providing a partition plate 122 on the dense electrolyte 102 of the solid oxide electrochemical cell 11. The solid oxide electrochemical stack may further have a sealing material 123 between the partition plate 122 and the separator 121. The electrolytic cell stack 10 may further have a plurality of gas channels on the outer periphery of the solid oxide electrochemical cells 11 that penetrate along the stacking direction of the solid oxide electrochemical cells 11. One of the gas channels constitutes a channel for the raw material gas supplied to the fuel electrode 103 and air electrode 101, respectively, and for the reaction product gas generated by the fuel electrode 103 and air electrode 101. Another of the gas channels may be connected to piping, for example.

[0022] To generate a large amount of electricity and hydrogen, an electrolytic cell stack 10 is formed by stacking multiple solid oxide type electrochemical cells 11. For example, in the case of a flat-plate type electrolytic cell, the electrolytic cell stack 10 is formed by stacking multiple flat-plate type electrolytic cells, supplying different gases to the air electrode 101 and fuel electrode 103 of each electrolytic cell, and having a structure that allows the electrolytic cells to be electrically connected in series.

[0023] The laminate 1, the lower clamping plate 2, and the upper clamping plate 3 can be fastened together, for example, by a combination of bolts and nuts or a compression mechanism (fastener) such as a spring. The electrolytic cell stack 10 is subjected to compressive force in the stacking direction by the lower clamping plate 2 and the upper clamping plate 3 positioned above and below the laminate 1, sealing the electrolytic cell stack 10 in particular to prevent hydrogen generated by the electrolytic reaction from leaking to the outside of the electrolytic cell stack 10.

[0024] A system with increased capacity achieved by connecting multiple electrolytic cell stacks 10 in series or parallel is called a module. Multiple electrolytic cell stacks 10 are arranged within the module. The supply gas to the air electrode 101 and fuel electrode 103 passes through a heating furnace such as an electric furnace and is supplied into the electrolytic cell stacks 10 from piping or the ends of the electrolytic cell stacks 10.

[0025] When the electrolytic cell stack 10 is operated for electrolysis purposes rather than power generation, it is important to recover the generated hydrogen without leaking it outside the electrolytic cell stack 10 or the electrolysis device.

[0026] Gas supply to and discharge from the air electrode 101 and fuel electrode 103 can be performed, for example, using piping or end manifolds. The electrolytic cell stack 10 is placed and fixed, for example, on a frame inside a heating furnace. The chamber of the heating furnace is covered with insulating material, but it is connected to the ground at least in one place through the insulating material, and there may be some heat dissipation from that part to the ground. The laminate 1 is less affected by heat dissipation because high-temperature gas flows through it. At the ends of the electrolytic cell stack 10 where there are no gas flow paths, and at the connections between the electrolytic cell stack 10 and other elements, a temperature gradient may occur during the operation of the electrolytic device. This temperature gradient may cause thermal deformation at the ends of the electrolytic cell stack 10.

[0027] Figure 3 is a schematic diagram illustrating thermal deformation. During operation of the electrolytic device, the ends of the electrolytic cell stack 10 become cold, while the central part becomes hot, creating a temperature gradient. As a result, components such as the clamping plates at the ends of the electrolytic cell stack 10 deform into a convex shape toward the laminate 1. The laminate 1 may also deform due to thermal deformation, but the clamping plates are thinner than the laminate 1 and therefore more susceptible to thermal deformation. This thermal deformation can cause physical deformation that prevents the flatness from being maintained between the central and end parts of the electrolytic cell stack 10, and can also generate an opening force in the stacking direction from the central part toward the end part, potentially creating gaps in the electrolytic cell stack and causing gas to leak from the electrolytic cell stack 10.

[0028] In contrast, the electrolytic apparatus of the embodiment has a buffer structure connected to at least one of the clamping plates of the lower clamping plate 2 and the upper clamping plate 3 of the electrolytic cell stack 10, and for suppressing thermal deformation of at least one clamping plate. An example of an electrolytic cell stack 10 having a buffer structure will be described further below. The following description will focus on the case of an electrolytic apparatus, but is not limited to this. For example, in other electrochemical apparatuses such as SOFCs that have an electrochemical cell stack that performs an electrochemical reaction opposite to the electrolytic reaction of the electrolytic cell stack 10, the same effects as in the first to fourth embodiments can be obtained by providing a buffer structure similar to the buffer structure in the first to fourth embodiments described later.

[0029] (First embodiment) Figure 4 is a schematic diagram illustrating a first embodiment of the electrolytic device. Figure 4 shows the electrolytic cell stack 10. The following explanation will describe the differences between the electrolytic cell stack 10 shown in Figure 1 and the electrolytic cell stack 10 shown in Figure 1, and the explanation of other parts can be appropriately referred to in Figure 1.

[0030] The electrolytic cell stack 10 of the first embodiment further comprises a clamping plate 4 and a heat conductive member 5, in addition to the components of the electrolytic cell stack 10 shown in Figure 1.

[0031] The clamping plate 4 is provided, for example, on the opposite side of the laminate 1 of the lower clamping plate 2. The clamping plate 4 is provided in contact with the heat conductive member 5. The clamping plate 4 can be formed from a material applicable to, for example, the lower clamping plate 2 or the upper clamping plate 3.

[0032] The heat conductive member 5 forms a buffer structure. The heat conductive member 5 is provided in contact with the lower clamping plate 2. The heat conductive member 5 is, for example, positioned on the opposite side of the laminate 1 of the lower clamping plate 2 and in contact with the lower clamping plate 2. The heat conductive member 5 is, for example, positioned between the lower clamping plate 2 and the clamping plate 4 and in contact with the clamping plate 4. Not limited to the above, the heat conductive member 5 may be positioned on the opposite side of the laminate 1 of the upper clamping plate 3 and provided in contact with the upper clamping plate 3. In this case, the clamping plate 4 is provided on the opposite side of the laminate 1 of the upper clamping plate 3, and the heat conductive member 5 is positioned between the lower clamping plate 2 and the clamping plate 4 and in contact with the clamping plate 4.

[0033] Within the operating temperature range of the electrolytic cell stack 10, it is preferable that the thermal conductivity of the heat conductive member 5 is lower than the thermal conductivity of at least one of the clamping plates, the lower clamping plate 2 and the upper clamping plate 3. The operating temperature range of the electrolytic cell stack 10 is, for example, 600°C to 1000°C. Within the operating temperature range of the electrolytic cell stack 10, the thermal conductivity of the lower clamping plate 2 and the upper clamping plate 3 is, for example, 10 W / m·k to 50 W / m·k, and the thermal conductivity of the heat conductive member 5 is, for example, 0 W / m·k to 5 W / m·k. Within the operating temperature range of the electrolytic cell stack 10, it is preferable that the thermal conductivity of the heat conductive member 5 is lower than the thermal conductivity of the clamping plate 4. Within the operating temperature range of the electrolytic cell stack 10, the thermal conductivity of the clamping plate 4 is, for example, 10 W / m·k to 50 W / m·k.

[0034] The heat-conducting member 5 is preferably formed using a material that not only has low thermal conductivity but can also maintain flatness and strength in a high-temperature environment. For example, it may be formed using a ceramic member or a mica member.

[0035] The laminate 1, lower clamping plate 2, upper clamping plate 3, clamping plate 4, and heat conductive member 5 can be connected and fixed, for example, by fasteners (connectors) that penetrate these components. Examples of fasteners include combinations of bolts and nuts or springs.

[0036] By placing a heat conductive member 5 between the electrolytic cell stack 10 and at least one clamping plate, for example, when supplying gas from a gas supply source to the lower clamping plate 2 or the laminate 1, the region RA of the electrolytic cell stack 10 above the heat conductive member 5 is maintained at a high temperature by the supply gas. On the other hand, the region RB of the electrolytic cell stack 10 below the heat conductive member 5 forms a temperature gradient due to the effects of heat dissipation, as described above. However, since the clamping plate 4 is below the heat conductive member 5, it is less susceptible to thermal deformation and can maintain the fastening of the electrolytic cell stack 10. Therefore, the formation of gaps in the electrolytic cell stack 10 due to thermal deformation can be suppressed, and gas leakage from the electrolytic cell stack 10 can be suppressed.

[0037] (Second embodiment) Figure 5 is a schematic diagram illustrating a second embodiment of the electrolytic device. Figure 5 shows the electrolytic cell stack 10. The following explanation will describe the differences between this electrolytic cell stack 10 and the one shown in Figure 1, and for other parts, the explanation in Figure 1 can be appropriately referred to.

[0038] The electrolytic cell stack 10 of the second embodiment further comprises a heat conductive member 5 in addition to the configuration of the electrolytic cell stack 10 shown in Figure 1.

[0039] The heat conduction member 5 forms a buffer structure. The heat conduction member 5 is provided in contact with the lower clamping plate 2. The heat conduction member 5 is positioned, for example, on the opposite side of the laminate 1 of the lower clamping plate 2 and in contact with the lower clamping plate 2. The heat conduction member 5 is positioned, for example, between the lower clamping plate 2 and the frame 30 and in contact with the frame 30. Further explanation of the heat conduction member 5 can be found in the explanation in Figure 4.

[0040] Figure 6 is a schematic diagram showing an example of the structure of an electrolytic apparatus. Figure 6 shows electrolytic apparatus 100.

[0041] The electrolytic apparatus 100 comprises an electrolytic cell stack 10, a heating furnace 20, and a stand 30.

[0042] Figure 6 shows a plurality of electrolytic cell stacks 10. The plurality of electrolytic cell stacks 10 are arranged on at least one stand 30. The plurality of electrolytic cell stacks 10 are connected to a plurality of pipes, and supply gas may be supplied to the electrolytic cell stacks 10 from outside the heating furnace 20 via one of the plurality of pipes and a gas flow path, and exhaust gas may be discharged from the electrolytic cell stacks 10 to the outside of the heating furnace 20 via another of the plurality of pipes and a gas flow path.

[0043] The heating furnace 20 has a chamber 21 that houses the electrolytic cell stack 10. An example of the heating furnace 20 is an electric furnace. The heating furnace 20 can adjust the temperature of the electrolytic cell stack 10. The heating furnace 20 can adjust the operating temperature range of the electrolytic cell stack 10 to, for example, 600°C to 1000°C.

[0044] The support frame 30 is placed in the chamber 21. The support frame 30 is provided for supporting the electrolytic cell stack 10. The support frame 30 may have multiple support surfaces for supporting multiple electrolytic cell stacks 10. The support frame 30 may extend outside the chamber 21. The support frame 30 can be made of, for example, a conductive material such as a metal or an insulating material such as a ceramic.

[0045] By arranging the heat conductive member 5 between the electrolytic cell stack 10 and the support frame 30, for example, when supplying gas from a gas supply source to the lower clamping plate 2 or the laminate 1, the region RA of the electrolytic cell stack 10 above the heat conductive member 5 is maintained at a high temperature by the supply gas. On the other hand, the region RB of the electrolytic cell stack 10 below the heat conductive member 5 forms a temperature gradient due to the effects of heat dissipation, as described above. However, since the clamping plate 4 is below the heat conductive member 5, it is less susceptible to thermal deformation and can maintain the fastening of the electrolytic cell stack 10. Therefore, the formation of gaps in the electrolytic cell stack 10 due to thermal deformation can be suppressed, and gas leakage from the electrolytic cell stack 10 can be suppressed. Furthermore, in the second embodiment, the clamping plate 4 can be made unnecessary, thus simplifying the device configuration.

[0046] (Third embodiment) Figure 7 is a schematic diagram illustrating a third embodiment of the electrolytic device. Figure 7 shows the electrolytic cell stack 10. The following explanation will describe the differences between this electrolytic cell stack 10 and the one shown in Figure 1, and for other parts, the explanation in Figure 1 can be appropriately referred to.

[0047] The electrolytic cell stack 10 of the third embodiment further comprises a plurality of sealing members 6.

[0048] Multiple sealing members 6 form a buffer structure. Multiple sealing members 6 are provided in contact with the end of the laminate 1. Multiple sealing members 6 are arranged, for example, between the laminate 1 and the lower clamping plate 2 and provided in contact with the lower clamping plate 2. Not limited to the above, multiple sealing members 6 may be arranged on the opposite side of the laminate 1 from the lower clamping plate 2 and provided in contact with the upper clamping plate 3. In this case, multiple sealing members 6 are arranged between the laminate 1 and the upper clamping plate 3 and provided in contact with the upper clamping plate 3.

[0049] The multiple sealing members 6 include sealing member 6a and sealing member 6b. The multiple sealing members 6 have different coefficients of linear expansion within the operating temperature range of the electrolytic cell stack 10.

[0050] Figure 8 is a schematic diagram showing the planar shapes of multiple sealing members 6. Figure 8 shows sealing member 6a and sealing member 6b. Sealing member 6a and sealing member 6b are provided, for example, on the same plane of the lower clamping plate 2.

[0051] The sealing member 6a is provided in contact with the lower clamping plate 2. The sealing member 6a is provided, for example, in the center of the surface of the lower clamping plate 2. The sealing member 6a has a first coefficient of linear expansion in the operating temperature range of the electrolytic cell stack 10. The first coefficient of linear expansion is, for example, 5 × 10⁻⁶. -6 / K or more 40×10 -6 It is less than or equal to / K.

[0052] The sealing member 6b is provided around the sealing member 6a in contact with the lower clamping plate 2. The sealing member 6b may also be provided so as to surround the sealing member 6a. The sealing member 6a has a second coefficient of linear expansion in the operating temperature range of the electrolytic cell stack 10. The second coefficient of linear expansion is higher than the first coefficient of linear expansion. The second coefficient of linear expansion is, for example, 10 × 10 -6 / K or more 60×10 -6 It is less than or equal to / K.

[0053] The sealing members 6a and 6b can be formed using materials such as ceramics. For example, the coefficient of linear expansion of the sealing members 6a and 6b can be adjusted by varying the composition of the materials used for the sealing members 6a and 6b. Figure 8 shows an example where the planar shapes of the sealing members 6a and 6b are square, but the planar shapes of the sealing members 6a and 6b are not limited to squares and may be other shapes such as rectangles or circles.

[0054] By arranging multiple sealing members 6 with different coefficients of linear expansion between the electrolytic cell stack 10 and the support frame 30, even if the lower clamping plate 2 undergoes thermal deformation, the shape of the sealing members 6 can be made to conform to the effect of the thermal deformation of the lower clamping plate 2. This suppresses the formation of gaps in the electrolytic cell stack 10 due to thermal deformation, thereby suppressing gas leakage from the electrolytic cell stack 10.

[0055] The third embodiment can be appropriately combined with the first and second embodiments. Figures 9 and 10 are schematic diagrams showing modified examples of the third embodiment. As shown in Figure 9, a plurality of sealing members 6 may be arranged between the laminated body 1 of the electrolytic cell stack 10 shown in Figure 4 and the lower clamping plate 2. As shown in Figure 10, a plurality of sealing members 6 may be arranged between the laminated body 1 of the electrolytic cell stack 10 shown in Figure 5 and the lower clamping plate 2. Further descriptions of the plurality of sealing members 6 can be appropriately referenced from the descriptions of the plurality of sealing members 6 shown in Figures 7 and 8.

[0056] (Fourth embodiment) Figure 11 is a schematic diagram illustrating a fourth embodiment of the electrolytic apparatus. Figure 11 shows the electrolytic apparatus 100.

[0057] The electrolytic apparatus 100 includes an electrolytic cell stack 10, a heating furnace 20, a stand 30, and a flow path 40.

[0058] Figure 11 shows a plurality of electrolytic cell stacks 10. The plurality of electrolytic cell stacks 10 are arranged on at least one stand 30. Each electrolytic cell stack 10 does not necessarily have a heat conductive member 5 and a plurality of sealing members 6. Further description of the electrolytic cell stacks 10 can be appropriately referenced from the descriptions of other embodiments.

[0059] The heating furnace 20 has a chamber 21 that houses the electrolytic cell stack 10. An example of the heating furnace 20 is an electric furnace. The heating furnace 20 can adjust the temperature of the electrolytic cell stack 10. Further description of the heating furnace 20 can be found in the description of the heating furnace 20 shown in Figure 6.

[0060] The support frame 30 is placed in the chamber 21. The support frame 30 is provided for mounting the electrolytic cell stack 10.

[0061] The flow path 40 is provided extending between the electrolytic cell stack 10 and the stand 30 or inside the stand 30. The flow path 40 may be connected to the gas flow paths of multiple electrolytic cell stacks 10. At least one of the supply gas and exhaust gas flows through the flow path 40. The flow path 40 is composed of at least one pipe. The flow path 40 may have multiple pipes, through which the supply gas is supplied to the electrolytic cell stack 10, and through which the generated gas is discharged from the electrolytic cell stack 10. Further description of the stand 30 can be appropriately referenced from the description of the stand 30 shown in Figure 6.

[0062] The supply gas and generated gas flowing between the electrolytic cell stack 10 and the support frame 30 have temperatures that are high within the operating temperature range of the electrolytic cell stack 10. Therefore, by arranging the flow path 40 to allow gas to flow between the electrolytic cell stack 10 and the support frame 30, the temperature drop at the ends of the electrolytic cell stack 10 can be suppressed by convection. This suppresses the formation of a temperature gradient, thereby preventing the formation of gaps in the electrolytic cell stack 10 due to thermal deformation and suppressing gas leakage from the electrolytic cell stack 10.

[0063] The fourth embodiment can be appropriately combined with the first to third embodiments.

[0064] In the first to fourth embodiments, the electrolytic cell stack 10 was described as a flat-plate type cell stack, and the electrolytic cell stack 10 was described as being installed vertically downward on a frame inside a high-temperature furnace. However, these are just examples, and the same effects as in the first to fourth embodiments can be obtained even with electrolytic cell stacks 10 other than flat-plate type, or when the electrolytic cell stack 10 is installed, for example, vertically upward or vertically, by making the ends of the stacks similar. The first to fourth embodiments are particularly effective when applied to electrolytic cell stacks that perform electrolytic reactions in which it is important not to leak the generated hydrogen to the outside of the electrolytic cell stack 10.

[0065] Although several embodiments of the present invention have been described above, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0066] 1...Laminate, 2...Lower clamping plate, 3...Upper clamping plate, 4...Clamping plate, 5...Heat conductive member, 6...Sealing member, 6a...Sealing member, 6b...Sealing member, 10...Electrolytic cell stack, 11...Solid oxide type electrochemical cell, 20...Heating furnace, 21...Chamber, 30...Stand, 40...Flow channel, 100...Electrolytic device, 101...Air electrode, 102...Electrolyte, 103...Fuel electrode, 104...Support, 121...Separator, 122...Partition plate, 123...Sealing material, RA...Area, RB...Area.

Claims

1. A laminate containing multiple electrochemical cells, A first clamping plate provided in contact with the laminate, A heat conductive member provided in contact with the first clamping plate, An electrochemical cell stack comprising, Within the operating temperature range of the electrochemical cell stack, the thermal conductivity of the heat conductive member is lower than that of the first clamping plate. Electrochemical cell stack.

2. The system further comprises a second clamping plate provided in contact with the heat conductive member, The heat conductive member is positioned between the first clamping plate and the second clamping plate. The electrochemical cell stack according to claim 1.

3. The heat conductive member is a ceramic member or a mica member. The electrochemical cell stack according to claim 1.

4. The electrochemical cell stack is placed on a frame, The heat conductive member is positioned between the first clamping plate and the frame. The electrochemical cell stack according to claim 1.

5. The heat conductive member is a ceramic member or a mica member. The electrochemical cell stack according to claim 4.

6. A laminate containing multiple electrochemical cells, The first clamping plate and A plurality of sealing members with different coefficients of linear expansion are provided between the laminate and the first clamping plate, Equipped with, Electrochemical cell stack.

7. The plurality of sealing members are A first sealing member provided in contact with the first clamping plate and having a first coefficient of linear expansion within the operating temperature range of the electrochemical cell stack, A second seal member is provided in contact with the first clamping plate and around the first seal member, and has a second coefficient of linear expansion that is higher than the first coefficient of linear expansion in the operating temperature range of the electrochemical cell stack, including, The electrochemical cell stack according to claim 6.

8. The electrochemical cell stack comprises the one described in any one of claims 1 to 7, Electrochemical apparatus.

9. Electrochemical cell stack and A heating furnace that houses the electrochemical cell stack and adjusts the temperature of the electrochemical cell stack, A frame provided inside the heating furnace on which the electrochemical cell stack is placed, A gas flow path between the electrochemical cell stack and the support structure, It is equipped with, Between the electrochemical cell stack and the support frame, the temperature of the gas is within the operating temperature range of the electrochemical cell stack. Electrochemical apparatus.

10. The aforementioned flow path extends inside the frame, The electrochemical apparatus according to claim 9.

11. The aforementioned electrochemical cell stack is A laminate containing multiple electrochemical cells, A first clamping plate provided in contact with the laminate, A heat conductive member provided in contact with the first clamping plate, It is equipped with, Within the operating temperature range of the electrochemical cell stack, the thermal conductivity of the heat conductive member is lower than that of the first clamping plate. The electrochemical apparatus according to claim 9 or claim 10.

12. The aforementioned electrochemical cell stack is The system further comprises a second clamping plate provided in contact with the heat conductive member, The heat conductive member is positioned between the first clamping plate and the second clamping plate. The electrochemical apparatus according to claim 11.

13. The heat conductive member is a ceramic member or a mica member. The electrochemical apparatus according to claim 11.

14. The aforementioned electrochemical cell stack is A laminate containing multiple electrochemical cells, The first clamping plate and A plurality of sealing members with different coefficients of linear expansion are provided between the laminate and the first clamping plate, Equipped with, The electrochemical apparatus according to claim 9 or claim 10.

15. The plurality of sealing members are A first sealing member provided in contact with the first clamping plate and having a first coefficient of linear expansion within the operating temperature range of the electrochemical cell stack, A second seal member is provided in contact with the first clamping plate and around the first seal member, and has a second coefficient of linear expansion that is higher than the first coefficient of linear expansion in the operating temperature range of the electrochemical cell stack, including, The electrochemical apparatus according to claim 14.

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