Electrochemical apparatus

Abstract

This suppresses the decrease in production efficiency of gases generated by electrochemical cell stacks. [Solution] The electrochemical apparatus comprises an electrochemical cell stack having a plurality of electrochemical cells that generate a second gas from a first gas; a structure that covers the electrochemical cell stack and forms a space between itself and the electrochemical cell stack from which the first gas is supplied; a gas supply port for supplying the first gas from the space to the electrochemical cell stack; and a gas outlet for discharging the second gas from the electrochemical cell stack.

Description

Technical Field

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

Background Art

[0002] As one of the new energies, hydrogen is mentioned. As a field of use of this hydrogen, there is a fuel cell that converts chemical energy into electrical energy by electrochemically reacting hydrogen and oxygen. Fuel cells have high energy utilization efficiency and are being developed as large-scale distributed power sources, household power sources, and mobile power sources. Fuel cells are classified into solid polymer type, phosphoric acid type, molten carbonate type, solid oxide type, etc. according to the temperature range and the types of materials and fuels used. Among them, a solid oxide fuel cell (SOFC) that obtains electrical energy by an electrochemical reaction using an electrolyte made of a solid oxide is highly efficient. In addition, in the production of hydrogen, the electrolysis reaction method of water is well known, and as one of its methods, there is a solid oxide electrolysis cell (SOEC) that uses a high-temperature steam electrolysis method in which water is electrolyzed in a steam state at a high temperature, and it is characterized by being more efficient than the conventional electrolysis method of water. The operating principle of SOEC is the reverse reaction of SOFC, and SOEC uses an electrolyte made of a solid oxide like SOFC.

[0003] Solid oxide electrochemical cells used in electrochemical devices such as SOFC and SOEC have various shapes such as flat plate type, cylindrical type, cylindrical flat plate type, honeycomb type, etc. Also, these cells are stacked and integrated as a unit structure. For example, flat cells form a stack by laminating a plurality of cells through a conductive separator. The separator isolates the anode / cathode atmosphere and also serves to electrically connect the two electrodes. The separator may further serve to equalize the flow of reaction / exhaust gas.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] As mentioned above, cell stacks using flat-plate cells are formed by stacking electrochemical cells and separators, and in order to maintain gas sealing properties, materials such as glass, ceramics, and metals are used to construct a structure and configuration that prevents gas from leaking into and out of the stack through the stacking surfaces. However, sealing hydrogen, for example, at high temperatures and with a small molecular size is extremely difficult, and there are concerns that this will reduce the recovery efficiency and thus the hydrogen production efficiency, especially in SOECs that produce hydrogen.

[0006] The problem that this invention aims to solve is to suppress the decrease in production efficiency of gases generated by an electrochemical cell stack. [Means for solving the problem]

[0007] The electrochemical apparatus of the embodiment comprises an electrochemical cell stack having a plurality of electrochemical cells that generate a second gas from a first gas; a structure that covers the electrochemical cell stack and forms a space between itself and the electrochemical cell stack from which the first gas is supplied; a gas supply port for supplying the first gas from the space to the electrochemical cell stack; and a gas outlet for discharging the second gas from the electrochemical cell stack. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing an example of the structure of an electrochemical apparatus according to the first embodiment. [Figure 2] This is a schematic diagram showing an example of the structure of an electrochemical cell stack. [Figure 3] This is a schematic diagram showing an example of an electrochemical cell structure. [Figure 4]This is a schematic diagram showing an example of a cross-sectional structure of an electrochemical cell stack. [Figure 5] This is a schematic diagram showing the first modified example. [Figure 6] This is a schematic diagram showing a second modified example. [Figure 7] This is a schematic diagram showing a third modified example. [Figure 8] This is a schematic diagram illustrating a second embodiment of the electrochemical apparatus. [Figure 9] This is a schematic diagram showing an example of a cross-sectional structure of an electrochemical cell stack. [Modes for carrying out the invention]

[0009] 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.

[0010] In this specification, "to connect" may include not only direct connections but also indirect connections, unless otherwise specified. Furthermore, in this specification, "to connect" may include not only physical connections but also electrical connections, unless otherwise specified.

[0011] (First embodiment) Figure 1 is a schematic diagram showing an example of the structure of an electrochemical apparatus according to the first embodiment. Figure 1 schematically shows an example of the structure of electrochemical apparatus 1.

[0012] The electrochemical apparatus 1 comprises an electrochemical cell stack 10, a structure 20, gas supply ports IN (IN1, IN2, etc.), and gas outlets OUT (OUT1, OUT2, etc.). Note that the number of gas supply ports IN and gas outlets OUT are not limited to those shown in Figure 1.

[0013] The electrochemical cell stack 10 can perform an electrochemical reaction using a gas (supply gas) supplied to the electrochemical cell stack 10 and discharge a gas (generated gas) generated by the electrochemical reaction. The electrochemical cell stack 10 may be provided separately from the structure 20.

[0014] FIG. 2 is a schematic diagram showing a structural example of an electrochemical cell stack. FIG. 2 is a schematic diagram showing each component of the electrochemical cell stack 10.

[0015] The electrochemical cell stack 10 is a solid oxide type electrochemical stack having an electrochemical cell 111 such as a solid oxide flat type electrochemical cell. The electrochemical cell stack 10 has a plurality of electrochemical cells 111. The plurality of electrochemical cells 111 are stacked in order. The stacking of the plurality of electrochemical cells 111 is provided between an upper clamping plate 101 and a lower clamping plate 102. The upper clamping plate 101 and the lower clamping plate 102 are, for example, metal conductive plates. The number of stacked layers of the plurality of electrochemical cells 111 is not particularly limited. The shape and specifications of the flat type cell of the electrochemical cell stack 10 are not particularly limited. For example, the shape of the electrochemical cell stack 10 may be square, rectangular, circular, etc., and for the support type of the electrochemical cell stack 10, an electrode support type, an electrolyte support type, a support type by other supports, etc. can be mentioned.

[0016] FIG. 3 is a schematic diagram showing a structural example of an electrochemical cell. FIG. 3 schematically shows a cross-sectional structure example in the thickness direction of the electrochemical cell 111. The electrochemical cell 111 has a hydrogen electrode 11, an electrolyte 12, and an oxygen electrode 13. The electrochemical cell 111 is connected to a power source that can supply, for example, a voltage or current for performing an electrochemical reaction. The power source may be connected to the electrochemical cell 111 through wiring penetrating the structure 20.

[0017] The electrochemical reaction by the electrochemical cell stack 10 is carried out, for example, as follows. A supply gas G1 such as carbon dioxide gas and water vapor is supplied to the hydrogen electrode 11 side. By the electrochemical reaction at the hydrogen electrode 11, for example, hydrogen gas can be generated from water vapor, and carbon monoxide gas can be generated from carbon dioxide gas. Generated gases such as carbon dioxide gas, water vapor, hydrogen gas, and carbon monoxide gas are discharged from the hydrogen electrode 11 side.

[0018] By the electrochemical reaction at the oxygen electrode 13, oxygen can be generated. Air having an oxygen concentration higher than the oxygen concentration in the atmosphere is discharged from the oxygen electrode 13 side. A gas such as air may be supplied to the oxygen electrode 13 side. The air is supplied, for example, to purge oxygen generated during electrolysis.

[0019] The hydrogen electrode 11 is, for example, porous and has conductivity for electrons and ions. Examples of the porous electron and ion conductor include a mixed sintered body (cermet) of a metal and a solid oxide. Examples of the solid oxide include yttria-stabilized zirconia, scandia-stabilized zirconia, etc. The hydrogen electrode 11 may further have a catalyst for promoting the electrochemical reaction of the supply gas, for example. The catalyst includes, 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 may be, for example, a metal component of an electric conductor, or may be supported on the surface of an electric conductor. The catalyst may form a catalyst layer provided on the surface of the electric conductor. The supply gas can pass through the inside of the porous hydrogen electrode 11.

[0020] The oxygen electrode 13 is, for example, porous and has conductivity for electrons and ions. Examples of the porous electron and ion conductor include perovskite-type oxides and the like, and have a catalyst function for promoting the electrochemical reaction. The supply gas can pass through the inside of the porous oxygen electrode 13.

[0021] The electrolyte 12, for example, has ionic conductivity that does not conduct electrons. Examples of ionic conductors include solid oxides such as stabilized zirconia, perovskite-type oxides, and molded ceria-based solid solutions.

[0022] The electrochemical cell stack 10 can isolate the atmospheres of adjacent electrochemical cells 111 by using separators 112 that are conductive, impermeable to gas, and prevent interference between the gas atmospheres of each electrode of the cells. Furthermore, the atmospheres of the hydrogen electrode 11 and oxygen electrode 13 of the same electrochemical cell 111 can be isolated by providing a sealing member 115 on top of the separator 112. The electrochemical cell stack 10 may also have a conductive member 113 between the electrochemical cell 111 and the separator 112, a conductive member 114 on top of the electrochemical cell 111, and a sealing member 115 between the insulating member 116 and the separator 112, or between the electrochemical cell 111 and the insulating member 116. The electrochemical cell stack 10 may further have multiple gas channels penetrating the separator 112, sealing member 115, and insulating member 116 along the stacking direction of the electrochemical cells 111. Multiple gas channels constitute the channels for supply gas supplied to the oxygen electrode 13 and the hydrogen electrode 11, respectively, and for generated gas produced by the oxygen electrode 13 and the hydrogen electrode 11. For example, gas channels can be formed by forming openings in the separator 112 or the sealing member 115. The shape of the openings is not particularly limited.

[0023] The electrochemical cell 111, separator 112, conductive member 113, conductive member 114, sealing member 115, insulating member 116, upper clamping plate 101, and lower clamping plate 102 can be fastened together, for example, by a combination of bolts and nuts or a compression mechanism (fastener) such as a spring. The clamping plates such as the upper clamping plate 101 and the lower clamping plate 102 are also called end plates. The electrochemical cell stack 10 is subjected to compressive force in the stacking direction by the upper clamping plate 101 and the lower clamping plate 102, sealing the electrochemical cell stack 10 in particular to suppress leakage of hydrogen generated by the electrochemical reaction to the outside of the electrochemical cell stack 10.

[0024] The structure 20 covers the electrochemical cell stack 10. The structure 20 may cover multiple electrochemical cell stacks 10. The structure 20 can be formed using a dense material. Examples of materials for the structure 20 include stainless steel and ceramics. Figure 1 shows a structure in which a stack of multiple electrochemical cells 111 is surrounded by the structure 20 and a lower clamping plate 102, but the structure is not limited to the above. The structure 20 forms a space S between the structure 20 and the electrochemical cell stack 10. The space S is formed between the electrochemical cell stack 10 and the inner wall surface of the structure 20. The space S is in contact with the inner wall surface of the structure 20. The structure 20 may be a chamber in a heating furnace such as an electric furnace.

[0025] The upper clamping plate 101 may be provided at a distance from the structure 20. The upper clamping plate 101 has a gas supply port IN1. The gas supply port IN1 is connected to a space S. The gas supply port IN1 is provided to supply supply gas G1 from the space S to the electrochemical cell stack 10. The supply gas G1 includes, for example, water vapor in the case of water vapor electrolysis. The gas supply port IN1 is through which the supply gas G1 supplied to the electrochemical cell stack 10 can flow.

[0026] In the case of an electrochemical apparatus such as the one shown in Figure 8, which will be described later, the lower clamping plate 102 has a gas supply port IN2, a gas outlet OUT1, and a gas outlet OUT2.

[0027] Gas supply port IN2 is provided at a distance from gas supply port IN1. Gas supply port IN2 is connected to space S. Supply gas G1 introduced into space S from outside the structure 20 can flow through gas supply port IN2. Gas supply port IN2 may be connected via piping to a gas supply source for supplying supply gas G1. Gas supply port IN2 is not directly connected to gas supply port IN1, but is indirectly connected via space S. Note that gas supply port IN2 may be provided in the structure 20.

[0028] The gas outlet OUT1 is connected to the electrochemical cell stack 10 without being directly connected to the space S. The exhaust gas G2A discharged from the electrochemical cell stack 10 can flow through the gas outlet OUT1. The exhaust gas G2A includes unreacted gases from the supply gas, such as water vapor, and product gases, such as hydrogen gas produced by the hydrogen electrode 11.

[0029] Gas outlet OUT2 is connected to the electrochemical cell 111 without being directly connected to space S. Exhaust gas G2B discharged from the electrochemical cell 111 can flow through gas outlet OUT2. Exhaust gas G2B includes product gases such as oxygen gas produced by the oxygen electrode. Preferably, gas outlet OUT2 is not connected to gas outlet OUT1.

[0030] As described above, the inside of the electrochemical cell stack 10 has a structure that allows for the supply and discharge of gas. The gas supplied from the gas supply port IN is distributed to one side of each electrochemical cell 111, where an electrochemical reaction takes place, and then the gas is discharged from the gas discharge port OUT.

[0031] Regarding the gas supplied to the electrochemical cell stack 10, when used for electrolysis, a supply gas such as water vapor or carbon dioxide gas is introduced to one electrode (hydrogen electrode 11) of the electrochemical cell 111, but this is not particularly limited, and the target gas to be electrolyzed is introduced. Furthermore, the type of gas supplied to the other electrode (oxygen electrode 13) of the electrochemical cell 111 is irrelevant, and gas may not be supplied at all.

[0032] Space S is sealed except for, for example, the gas supply port IN2. The supply gas G1A supplied to space S through gas supply port IN2 is supplied into the electrochemical cell stack 10, for example, through gas supply port IN1 provided in the electrochemical cell stack 10. The product gas generated by the electrochemical reaction in the electrochemical cell stack 10 is discharged to the outside of the electrochemical cell stack 10, for example, through gas outlets OUT1 and OUT2.

[0033] The structure 20 may have one or more gas supply ports IN. If there are multiple ports, they may be separated by gas type, or the same gas may be divided and supplied. This allows for the simplification of the electrochemical cell stack 10, for example, in the case of an electrochemical apparatus as shown in Figure 6, which will be described later, by eliminating the need to provide a manifold (space) within the electrochemical cell stack 10 for distributing the reaction gas to each electrochemical cell. Furthermore, the location of the gas supply ports IN is not particularly limited. The number and location of the gas supply ports IN are not particularly limited.

[0034] Furthermore, as shown in Figure 1, by not forming a gas supply port for supplying reaction gas to the counter electrode, the electrochemical cell stack 10 can be simplified without providing a manifold (space) within the electrochemical cell stack 10 for uniformly distributing the reaction gas within the electrochemical cell stack 10.

[0035] When hydrogen gas is produced by steam electrolysis, for example, a supply gas G1 containing at least water vapor is supplied to space S from a gas supply port IN2. The gas supplied to space S, containing at least the supply gas G1, is supplied into the electrochemical cell stack 10 from a gas supply port IN1 of the electrochemical cell stack 10. The water vapor distributed to each electrochemical cell 111 in the electrochemical cell stack 10 is converted to hydrogen by an electrochemical reaction such as electrolysis, and is discharged outside the electrochemical cell stack 10 through a gas outlet OUT1 along with the unreacted water vapor. In this case, because hydrogen gas has a particularly small molecular diameter, it leaks into space S through gaps in the electrochemical cell stack 10, as shown in Figure 4. Figure 4 is a schematic diagram showing an example of a cross-sectional structure of the electrochemical cell stack. Figure 4 schematically shows an example of a cross-sectional structure in the planar direction of the electrochemical cell stack 10. Gaps are formed, for example, at the interface between the separator 112 and the sealing member 115.

[0036] The leaked hydrogen gas G3A is supplied to the space S and, along with at least water vapor, is again supplied into the electrochemical cell stack 10 via the gas supply port IN1. In conventional electrochemical devices, hydrogen gas that leaks outside the electrochemical cell stack reacts with the surrounding oxygen gas and is consumed. In contrast, in the electrochemical device of the first embodiment, by providing the structure 20 to form the space S, the leaked gas G3A can be resupplied into the electrochemical cell stack 10 without being consumed, thereby suppressing a decrease in the production efficiency of the generated gas. Furthermore, even if water vapor leaks as leaked gas G3A, it can be resupplied into the electrochemical cell stack 10 as a supply gas, thereby improving fuel utilization.

[0037] The same applies when producing hydrogen gas and carbon monoxide gas by electrolysis of water vapor and carbon dioxide gas. For example, a supply gas G1 containing at least water vapor and carbon dioxide gas is supplied to space S from gas supply port IN2. The gas supplied to space S, containing at least water vapor and carbon dioxide gas, is then supplied into the electrochemical cell stack 10 from gas supply port IN1.

[0038] The water vapor and carbon dioxide gas distributed to each electrochemical cell 111 within the electrochemical cell stack 10 are converted into hydrogen gas and carbon monoxide gas by electrochemical reactions such as electrolysis, and together with the unreacted water vapor and carbon dioxide gas, are discharged outside the electrochemical cell stack 10 through the gas outlet OUT1. At this time, hydrogen gas, carbon monoxide gas, water vapor, and carbon dioxide gas leak into the space S through gaps in the electrochemical cell stack 10.

[0039] These leaked gases G3A are supplied to the space S and, along with gases containing at least water vapor and carbon dioxide, are again supplied to the electrochemical cell stack 10 via the gas supply port IN1. In conventional electrochemical devices, hydrogen gas and carbon monoxide gas that leak outside the stack react with oxygen gas in the surrounding area and are consumed. In contrast, in the electrochemical device of the first embodiment, by providing the structure 20 to form the space S, the leaked gases G3A can be resupplied into the electrochemical cell stack 10 without being consumed, thus suppressing a decrease in the production efficiency of the generated gas. Furthermore, even if water vapor or carbon dioxide gas leaks, it can be resupplied into the electrochemical cell stack 10 as supply gas, thereby improving fuel utilization.

[0040] (First variation) Figure 5 is a schematic diagram showing a first modification of the first embodiment. As shown in Figure 5, the gas supplied to the space S may be discharged from the inside of the structure 20 to the outside and then supplied again from the outside of the structure 20 to the space S. The gas in the space S can be discharged to the outside of the space S via, for example, a pipe P and then resupplied to the inside of the space S. The inlet and outlet of the pipe P are attached to the structure 20 and connected to the space S. The pipe P may penetrate the structure 20. As shown in Figure 5, the upper clamping plate 101 may be in contact with the inner wall surface of the structure 20, and the gas supply port IN1 may be indirectly connected to the space S via the pipe P without being directly connected to the space S.

[0041] (Second variation) Figure 6 is a schematic diagram showing a second modified example of the first embodiment. As shown in Figure 6, the supply gas G1 may be supplied to each electrochemical cell 111. For example, the supply gas G1 can be supplied to each electrochemical cell 111 by removing the ends of the separator 112 and the sealing member 115 to form a notch and providing a gas supply channel. The supply gas G1 can be distributed and supplied to all electrochemical cells 111 via the gas supply channel. The gas supply channel may be indirectly connected to the gas supply port IN2 via a space S.

[0042] (Third variation) Figure 7 is a schematic diagram showing a third modified example of the first embodiment. As shown in Figure 7, the electrochemical cell stack 10 may be surrounded by a structure 20. The electrochemical cell stack 10 may be fixed inside the structure 20 via fasteners. The upper clamping plate 101 and the lower clamping plate 102 may be spaced apart from the structure 20. The gas supply port IN2 may be formed through the structure 20 and connected to space S. The gas outlet OUT1 may be connected to the outside of the structure 20 via piping P1. The gas outlet OUT2 may be connected to the outside of the structure 20 via piping P2. By providing piping P1 and piping P2, it is possible to suppress the supply of exhaust gases G2A and G2B discharged from the electrochemical cell stack 10 into space S.

[0043] The first to third variations can be combined as appropriate.

[0044] The supply gas or exhaust gas is supplied or discharged by applying pressure to the electrochemical cell stack 10 or the space S. By adjusting the pressure in the space S to be higher than the pressure inside the electrochemical cell stack 10, the amount of gas leakage from the inside to the outside of the electrochemical cell stack 10 can be reduced, and even if the supply gas leaks from outside the electrochemical cell stack 10 into the electrochemical cell stack 10, the leaked gas can be used as fuel. The means and methods for increasing the pressure in the space S are not particularly limited.

[0045] By drawing in exhaust gas from the gas outlet OUT, the pressure inside the electrochemical cell stack 10 can be reduced, making it easier to supply supply gas into the electrochemical cell stack 10. This suppresses gas leakage from inside the electrochemical cell stack 10 and improves efficiency. There are no particular restrictions on the means or methods for drawing in exhaust gas from the gas outlet OUT. Exhaust gas may be drawn in using a suction device at the gas outlet OUT.

[0046] (Second embodiment) Figure 8 is a schematic diagram illustrating a second embodiment of the electrochemical apparatus. Figure 8 schematically shows an example of the structure of the electrochemical apparatus 1. The following describes the differences from the electrochemical cell stack 10 shown in Figure 1, and for other parts, the description of the first embodiment can be appropriately referenced.

[0047] The electrochemical apparatus 1 shown in Figure 8 differs from the electrochemical apparatus 1 shown in Figure 1 in that it supplies supply gas G1A and supply gas G1B as supply gas G1.

[0048] The lower clamping plate 102 has a gas supply port IN2, a gas supply port IN3, a gas outlet OUT1, and a gas outlet OUT2.

[0049] The gas supply port IN2 is connected to the space S. The supply gas G1A supplied to the space S can flow through the gas supply port IN2. The supply gas G1A contains oxygen gas. Preferably, the supply gas G1A does not contain nitrogen gas.

[0050] The gas supply port IN3 is connected to the electrochemical cell stack 10 without being connected to the space S. The supply gas G1B supplied to the electrochemical cell stack 10 can flow through the gas supply port IN3. The supply gas G1B contains water vapor. The supply gas G1B may also contain carbon dioxide gas or hydrogen gas.

[0051] The gas outlet OUT1 is connected to the electrochemical cell stack 10 without being connected to space S. The exhaust gas G2A discharged from the electrochemical cell stack 10 can flow through the gas outlet OUT1.

[0052] The gas outlet OUT2 is connected to the electrochemical cell stack 10 without being connected to space S. The exhaust gas G2B discharged from the electrochemical cell stack 10 can flow through the gas outlet OUT2.

[0053] When generating product gases such as hydrogen gas or carbon monoxide gas through an electrochemical reaction of the supply gas, supply gas G1A containing at least oxygen gas is supplied to space S from gas supply port IN2, and supply gas G1B containing at least water vapor and carbon dioxide gas is supplied to the electrochemical cell stack 10 from gas supply port IN3 without passing through space S. The gas supplied to space S, which contains at least supply gas G1A, is supplied into the electrochemical cell stack 10 from gas supply port IN1 of the electrochemical cell stack 10. The water vapor contained in supply gas G1B distributed to each electrochemical cell 111 in the electrochemical cell stack 10 is converted to hydrogen by an electrochemical reaction such as electrolysis, and is discharged outside the electrochemical cell stack 10 through gas outlet OUT1 along with unreacted water vapor. In addition, the oxygen gas contained in supply gas G1A distributed to each electrochemical cell 111 in the electrochemical cell stack 10 is supplied to the oxygen electrode 13 and discharged outside the electrochemical cell stack 10 through gas outlet OUT2.

[0054] When generating product gases such as hydrogen gas or carbon monoxide gas through the electrochemical reaction of the supply gas, gas containing the supply gas G1A in space S may leak from space S into the electrochemical cell stack 10, as shown in Figure 9. Figure 9 is a schematic diagram showing an example of the cross-sectional structure of the electrochemical cell stack. Figure 9 schematically shows an example of the cross-sectional structure in the planar direction of the electrochemical cell stack 10. The leaked gas G3B from space S contains oxygen gas. In contrast, in the electrochemical apparatus of the second embodiment, by providing the structure 20 to form space S, even if oxygen gas leaks from outside the electrochemical cell stack 10 into the electrochemical cell stack 10, oxygen gas can be used as the supply gas within the electrochemical cell stack 10, thus suppressing a decrease in the production efficiency of the product gas.

[0055] The second embodiment can be appropriately combined with the first embodiment. For example, the structure of the first to third modified versions of the first embodiment may be applied to the second embodiment.

[0056] 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]

[0057] 1... Electrochemical apparatus, 10... Electrochemical cell stack, 11... Hydrogen electrode, 12... Electrolyte, 13... Oxygen electrode, 20... Structure, 101... Upper clamping plate, 102... Lower clamping plate, 111... Electrochemical cell, 112... Separator, 113... Conductive member, 114... Conductive member, 115... Seal member, 116... Insulating member, G1... Supply gas, G1A... Supply gas, G1B... Supply gas, G2A... Exhaust gas, G2B... Exhaust gas, G3A... Leak gas, G3B... Leak gas, IN... Gas supply port, IN1... Gas supply port, IN2... Gas supply port, IN3... Gas supply port, OUT... Gas outlet, OUT1... Gas outlet, OUT2... Gas outlet, P... Piping, P1... Piping, P2... Piping, S... Space.

Claims

1. An electrochemical cell stack having multiple electrochemical cells that generate a second gas from a first gas, A structure that covers the electrochemical cell stack and forms a space between itself and the electrochemical cell stack through which the first gas is supplied, A gas supply port for supplying the first gas from the space to the electrochemical cell stack, A gas outlet for discharging the second gas from the electrochemical cell stack, An electrochemical apparatus equipped with the following:

2. The aforementioned electrochemical cell stack is Upper clamping plate and Lower clamping plate and A separator is provided so as to surround one of the aforementioned multiple electrochemical cells, and is conductive and impermeable to gases, A conductive member provided between one of the aforementioned electrochemical cells and another, A sealing member provided on the separator, It further possesses, The gas supply port is provided on the lower clamping plate or the upper clamping plate. The gas outlet is provided on the lower clamping plate or the upper clamping plate. The electrochemical apparatus according to claim 1.

3. The structure, the lower clamping plate, or the upper clamping plate has a second gas supply port for introducing the first gas into the space. The electrochemical apparatus according to claim 2.

4. The first gas contains water vapor, The electrochemical apparatus according to claim 1.

5. The first gas includes carbon dioxide gas and water vapor. The electrochemical apparatus according to claim 1.

6. The first gas includes oxygen gas. The electrochemical apparatus according to claim 1.

7. The second gas includes water vapor and hydrogen gas. The electrochemical apparatus according to claim 1.

8. Having multiple gas supply ports, The electrochemical apparatus according to claim 1.

9. Multiple electrochemical cells have a hydrogen electrode and an oxygen electrode. The electrochemical cell stack does not have a gas supply port for supplying gas to the oxygen electrode. The electrochemical apparatus according to claim 1.

10. The pressure in the aforementioned space is higher than the pressure inside the electrochemical cell stack. The electrochemical apparatus according to claim 1.

11. The second gas from the gas outlet is sucked out and discharged by a suction device. The electrochemical apparatus according to claim 1.

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