Gas recovery system and method for manufacturing electrode film

Abstract

To provide a gas recovery system whose capability of recovering gas to be recovered can be prevented from deteriorating by preventing an electrode film constituting an electrochemical cell from warping, and a manufacturing method for an electrode film that is used in the gas recovery system.SOLUTION: A carbon dioxide recovery system 1 comprises electrochemical cells 101 and a gas passage 102, and recovers gas to be recovered from mixed gas by an electrochemical reaction. The electrochemical cell 101 comprises an action electrode 104 including an adsorbent that adsorbs gas to be recovered, and a counter electrode 106 that gives and receives electrons to / from the action electrode 104. The gas passage 102 is formed between the plurality of laminated electrochemical cells 101, and allows mixed gas to flow therethrough. At least one of the action electrode 104 and the counter electrode 106 is composed of an electrode film 200. The electrode film 200 has a plurality of regions 110 smaller than the electrochemical cells, and suppressing parts 120 for preventing the electrode film 200 from warping are arranged adjacently to the plurality of regions 110.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a gas recovery system for recovering a target gas from a mixed gas containing the target gas and a method for manufacturing an electrode film used in the gas recovery system.

Background Art

[0002] Conventionally, Patent Document 1 discloses a technique related to a carbon dioxide recovery device for recovering carbon dioxide as a target gas from a mixed gas containing carbon dioxide. The carbon dioxide recovery device of Patent Document 1 includes an electrochemical cell that adsorbs carbon dioxide by an electrochemical reaction.

[0003] The electrochemical cell is formed as a laminate in which a working electrode, a counter electrode, a working electrode current collector, a counter electrode current collector, etc., each formed in a flat plate shape, are laminated. The working electrode contains a carbon dioxide adsorbent that absorbs carbon dioxide from the mixed gas. The counter electrode contains an electrochemically active auxiliary material that exchanges electrons with the working electrode. The working electrode current collector is an electrode that abuts on the working electrode. The counter electrode current collector is an electrode that abuts on the counter electrode.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, in a carbon dioxide recovery device such as that of Patent Document 1, a plurality of electrochemical cells are stacked and arranged, and the mixed gas is configured to flow through a flow path formed between the electrochemical cells. Also, the working electrode and the counter electrode, which are electrode films in the electrochemical cell, have a relatively large film thickness and a low metal-based content compared to a battery or the like, and thus tend to warp.

[0006] Therefore, it is assumed that the amount of carbon dioxide recovered in a carbon dioxide recovery device is affected by the width of the flow path formed between the electrochemical cells, and it is considered important to suppress warping and distortion of the electrochemical cells. However, Patent Document 1 does not mention anything about suppressing warping of the electrode film in the electrochemical cell.

[0007] In view of the above, one objective of this disclosure is to provide a gas recovery system that can suppress a decrease in the recovery capacity of the target gas by suppressing the warping of the electrode film constituting the electrochemical cell. A second objective of this disclosure is to provide a method for manufacturing an electrode film that can suppress warping of the electrode film of an electrochemical cell used in a gas recovery system. [Means for solving the problem]

[0008] A gas recovery system according to a first aspect of this disclosure is a gas recovery system that recovers a target gas from a mixed gas by an electrochemical reaction, comprising an electrochemical cell (101) and Spacer (300) and The electrochemical cell includes a gas channel (102). The electrochemical cell comprises a working electrode (104) containing an adsorbent for adsorbing the gas to be recovered, and a counter electrode (106) that exchanges electrons with the working electrode. When a voltage is applied between the working electrode and the counter electrode, electrons are supplied from the counter electrode to the working electrode, and the adsorbent adsorbs the gas to be recovered in response to the supply of electrons. Spacers are placed between a plurality of the stacked electrochemical cells, with a gap between them in the direction in which the electrochemical cells are stacked. The gas flow path is formed between the stacked electrochemical cells and the spacers, and is a flow path through which the mixed gas flows.

[0009] At least one of the working electrode and the counter electrode is composed of an electrode film (200). The electrode film has multiple regions (110) smaller than the size of the electrochemical cell, and these regions are adjacent to suppression portions (120, 120a, 120b) for suppressing warping of the electrode film. The suppression portion is formed linearly with no electrode film formed thereon, or with a film thickness smaller than the film thickness of the multiple regions.

[0010] According to the gas recovery system, warping of the electrode film can be suppressed by placing suppression sections adjacent to multiple regions of the electrode film. This suppresses warping of the electrochemical cell, making it possible to appropriately manage the width of the gas flow path arranged between the electrochemical cells. Therefore, the gas recovery system can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path due to warping of the electrochemical cell.

[0011] Furthermore, a method for manufacturing an electrode film used in a gas recovery system according to a second aspect of this disclosure is a method for manufacturing an electrode film (200) used in a gas recovery system that recovers a target gas from a mixed gas by an electrochemical reaction, and which constitutes at least one of a working electrode and a counter electrode. The gas recovery system includes an electrochemical cell (101) and a gas flow path (102). The electrochemical cell comprises a working electrode (104) containing an adsorbent for adsorbing the target gas contained in the mixed gas, and a counter electrode (106) that exchanges electrons with the working electrode. In the electrochemical cell, when a voltage is applied between the working electrode and the counter electrode, electrons are supplied from the counter electrode to the working electrode, and the adsorbent adsorbs the target gas in response to the supply of electrons. The gas flow path is formed between a plurality of the electrochemical cells arranged in a stack and is a flow path through which the mixed gas flows.

[0012] A method for manufacturing an electrode film used in a gas recovery system comprises a placement step, a coating step, a region formation step, and a drying step. In the placement step, a masking member (220) having multiple openings (220a) is placed on a substrate (210). In the coating step, the constituent material (200a) of the electrode film is coated onto the substrate and the masking member. In the region formation step, after the coating step is completed, the masking member is removed to form multiple regions (110) smaller than the size of the electrochemical cell, and suppression parts (120) adjacent to the regions to suppress warping of the electrode film. In the drying step, the constituent material of the electrode film coated on the substrate is dried.

[0013] Therefore, according to the manufacturing method for electrode films used in gas recovery systems, an electrode film having multiple regions and suppression parts can be efficiently manufactured by performing a placement step, a coating step, a region formation step, and a drying step. By using an electrode film manufactured by this method, it is possible to suppress the warping of electrochemical cells and appropriately control the width of the gas flow path arranged between electrochemical cells. Therefore, a gas recovery system using an electrode film manufactured by this method can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path due to the warping of electrochemical cells.

[0014] The reference numerals in parentheses next to each means described in this section and in the claims indicate the correspondence with the specific means described in the embodiments described later. [Brief explanation of the drawing]

[0015] [Figure 1] This is a conceptual diagram showing the overall configuration of the carbon dioxide capture system according to the first embodiment. [Figure 2] This is an explanatory diagram showing the configuration of a carbon dioxide capture device. [Figure 3] This is an explanatory diagram showing the configuration of an electrochemical cell in a carbon dioxide capture device. [Figure 4] This is an explanatory diagram showing an example of a method for manufacturing an electrode film used in a carbon dioxide recovery system according to the first embodiment. [Figure 5] This is an explanatory diagram regarding warpage in electrode films and substrates. [Figure 6] This is a schematic diagram showing an example of the configuration of a battery chemical cell according to the first embodiment. [Figure 7] This is a schematic diagram showing an example of the configuration of a carbon dioxide recovery device according to the first embodiment. [Figure 8] This is an explanatory diagram showing an example of a method for manufacturing an electrode film according to the second embodiment. [Figure 9] This is an explanatory diagram showing an example of a method for manufacturing an electrode film according to the third embodiment. [Figure 10] This is an explanatory diagram showing an example of a method for manufacturing an electrode film according to the fourth embodiment. [Figure 11] It is an explanatory diagram regarding a method for manufacturing an electrode film according to the fifth embodiment.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, a plurality of embodiments for implementing the present disclosure will be described while referring to the drawings. In each embodiment, the same reference numerals may be assigned to the parts corresponding to the matters described in the preceding embodiment, and duplicate explanations may be omitted. When only a part of the configuration is described in each embodiment, other embodiments described previously can be applied to other parts of the configuration. Not only combinations of parts that are explicitly shown to be combinable in each embodiment, but also partial combinations of embodiments are possible as long as there is no problem with the combination, even if not explicitly stated.

[0017] (First Embodiment) The first embodiment in the present disclosure will be described with reference to the drawings. The first embodiment is applied to a carbon dioxide recovery system 1 that separates and recovers carbon dioxide from a mixed gas containing carbon dioxide in the gas recovery system in the present disclosure. Therefore, the gas to be recovered in this embodiment is carbon dioxide.

[0018] As shown in FIG. 1, the carbon dioxide recovery system 1 according to the first embodiment includes a carbon dioxide recovery device 10, a pump 11, a flow path switching valve 12, a carbon dioxide utilization device 13, and a control device 14.

[0019] The carbon dioxide recovery device 10 separates and recovers carbon dioxide from the mixed gas. As the mixed gas, air or exhaust gas from an internal combustion engine can be used. The mixed gas also contains gases other than carbon dioxide. The mixed gas is supplied to the carbon dioxide recovery device 10. The carbon dioxide recovery device 10 discharges the mixed gas after carbon dioxide is removed or the recovered carbon dioxide. The detailed configuration of the carbon dioxide recovery device 10 will be described later.

[0020] The outlet of the carbon dioxide capture device 10 is connected to the inlet side of the pump 11. The pump 11 draws the mixed gas from which carbon dioxide has been removed, or the captured carbon dioxide, from the carbon dioxide capture device 10. Furthermore, the suction action of the pump 11 supplies the mixed gas to the carbon dioxide capture device 10.

[0021] In this embodiment, an example is described in which the pump 11 is located downstream of the carbon dioxide recovery device 10 in the gas flow direction. However, the pump 11 may also be located upstream of the carbon dioxide recovery device 10 in the gas flow direction.

[0022] The inlet side of the flow path switching valve 12 is connected to the discharge port of the pump 11. The flow path switching valve 12 is a three-way valve that switches the flow path of the gas flowing out of the carbon dioxide recovery device 10. One outlet of the flow path switching valve 12 is connected to the atmosphere, and the other outlet of the flow path switching valve 12 is connected to the carbon dioxide utilization device 13. Therefore, the flow path switching valve 12 switches between a flow path that allows the gas flowing out of the carbon dioxide recovery device 10 to flow to the atmosphere and a flow path that allows the gas flowing out of the carbon dioxide recovery device 10 to flow to the carbon dioxide utilization device 13.

[0023] The carbon dioxide utilization device 13 is a device that utilizes carbon dioxide. The carbon dioxide utilization device 13 can include, for example, a storage tank for storing carbon dioxide or a conversion device for converting carbon dioxide into fuel. The conversion device is a device that converts carbon dioxide into a hydrocarbon fuel such as methane. The hydrocarbon fuel may be a gaseous fuel at room temperature and pressure, or a liquid fuel at room temperature and pressure.

[0024] The control device 14 consists of a well-known microcomputer including a CPU, ROM, and RAM, and its peripheral circuits. The control device 14 performs various calculations and processes based on a control program stored in the ROM, and controls the operation of various controlled devices connected to the output side. More specifically, the control device 14 in this embodiment controls the operation of the carbon dioxide capture device 10, the pump 11, and the flow path switching valve 12.

[0025] Next, the configuration of the carbon dioxide capture device 10 used in the carbon dioxide capture system 1 will be explained with reference to Figures 2 and 3. As shown in Figure 2, the carbon dioxide capture device 10 has a housing 100 and a plurality of electrochemical cells 101. In this embodiment, the housing 100 is made of a metal material. The housing 100 may also be made of a resin material.

[0026] The housing 100 has a gas inlet and a gas outlet. The gas inlet is an opening for introducing the mixed gas into the housing 100. The gas outlet is an opening for releasing the mixed gas, after carbon dioxide has been removed, or the recovered carbon dioxide, from inside the housing 100.

[0027] The electrochemical cell 101 adsorbs carbon dioxide through an electrochemical reaction, separating and recovering it from the mixed gas. The electrochemical cell 101 also releases the adsorbed carbon dioxide through an electrochemical reaction. Multiple electrochemical cells 101 are housed in the enclosure 100.

[0028] The electrochemical cell 101 is formed in the shape of a rectangular flat plate. Multiple electrochemical cells 101 are stacked inside the housing 100 at regular intervals so that their plate surfaces are parallel to each other.

[0029] Multiple gas channels 102 are formed between adjacent electrochemical cells 101 to allow the mixed gas flowing in from the gas inlet to circulate. Therefore, the flow direction of the mixed gas is parallel to the plate surface of the electrochemical cell 101 and perpendicular to the stacking direction of the multiple electrochemical cells 101.

[0030] As shown in Figure 3, the electrochemical cell 101 includes a working electrode current collector 103, a working electrode 104, a counter electrode current collector 105, a counter electrode 106, a separator 107, and an electrolyte layer 108. The working electrode current collector 103, the working electrode 104, the counter electrode current collector 105, the counter electrode 106, and the separator 107 are all formed in the shape of rectangular flat plates.

[0031] The electrochemical cell 101 is formed as a laminate by stacking a working electrode current collector 103, a working electrode 104, a counter electrode current collector 105, a counter electrode 106, and a separator 107. The stacking direction in which the working electrode current collector 103, etc., are stacked in each individual electrochemical cell 101 coincides with the stacking direction in which multiple electrochemical cells 101 are stacked inside the housing 100.

[0032] The working electrode current collector 103 is a conductive member that contacts the working electrode 104 and electrically connects the working electrode 104 and the counter electrode 106. One flat surface of the working electrode current collector 103 is exposed to the mixed gas. The other flat surface of the working electrode current collector 103 is in contact with the working electrode 104. The working electrode current collector 103 has multiple working electrode openings (not shown) formed therein to expose the mixed gas on one flat surface side to the working electrode 104 on the other flat surface side.

[0033] Specifically, the working electrode current collector 103 in this embodiment is made of a porous metal material. Therefore, the working electrode opening in this embodiment is formed by multiple voids formed inside the working electrode current collector 103 communicating with each other. As the working electrode current collector 103, a porous metal material with a porosity of 50% or more can be used. The porosity is defined as the ratio of the volume of voids to the apparent volume. It is also possible to use carbon nonwoven fabric or the like as the working electrode current collector 103.

[0034] The working electrode 104 can adsorb and recover carbon dioxide from the mixed gas, and then desorb and release the recovered carbon dioxide. The working electrode 104 has a carbon dioxide adsorbent, a conductive additive, and a binder, and corresponds to an example of an electrode film 200. The carbon dioxide adsorbent, conductive additive, and binder are used in a mixture state. More specifically, fine particles of the carbon dioxide adsorbent and fine particles of the conductive additive are used in a state where they are held by the binder.

[0035] Carbon dioxide adsorbents are electroactive species that adsorb carbon dioxide by accepting electrons and desorb the adsorbed carbon dioxide by releasing electrons. Examples of carbon dioxide adsorbents include carbon materials, metal oxides, and polyanthraquinones.

[0036] The conductive additive forms a conductive path to the carbon dioxide adsorbent. Examples of conductive additives include carbon materials such as carbon nanotubes, carbon black, and graphene.

[0037] The binder is a binder that holds the carbon dioxide adsorbent and the conductive additive. As the binder, for example, a conductive resin made of a high-molecular-weight polymer can be used. As the conductive resin, an organic material such as epoxy resin containing Ag or the like as a conductive filler, or fluororesin such as polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF) can be used.

[0038] The counter electrode current collector 105 is a conductive member that contacts the counter electrode 106 and electrically connects the working electrode 104 and the counter electrode 106. One flat surface of the counter electrode current collector 105 is exposed to the mixed gas. The other flat surface of the counter electrode current collector 105 is in contact with the counter electrode 106. The counter electrode current collector 105 has multiple counter electrode openings (not shown) formed therein to expose the mixed gas on one flat surface side to the counter electrode 106 on the other flat surface side.

[0039] Specifically, the counter electrode current collector 105 in this embodiment is formed of a porous metal, similar to the working electrode current collector 103. Therefore, the counter electrode opening is formed by the communication of multiple voids formed inside the counter electrode current collector 105. It is preferable to use a porous metal with a void ratio of 70% or less as the counter electrode current collector 105.

[0040] The counter electrode 106 exchanges electrons with the working electrode 104 when the carbon dioxide adsorbent adsorbs or desorbs carbon dioxide. The counter electrode 106 comprises an electroactivating agent, a conductive additive, and a binder. The electroactivating agent, conductive additive, and binder are used in a mixture state. More specifically, in this embodiment, fine particles of the electroactivating agent and fine particles of the conductive additive are used in a state held by the binder.

[0041] The basic composition of the conductive additive and binder of the counter electrode 106 is the same as that of the conductive additive and binder of the working electrode 104. The electroactivating additive is an auxiliary electroactive species that transfers electrons with the carbon dioxide adsorbent of the working electrode 104, and is an active material with redox properties. As the active material, an organic compound having a π bond, a transition metal compound that can take on multiple oxidation states, or a metal complex that enables electron transfer by changing the valence of a metal ion can be used.

[0042] Examples of such metal complexes include cyclopentadienyl metal complexes such as ferrocene, nickerosene, and cobaltocene, or porphyrin metal complexes. These metal complexes may be polymers or monomers.

[0043] The separator 107 is positioned between the working electrode 104 and the counter electrode 106, separating them. The separator 107 is an insulating ion-permeable membrane that prevents physical contact between the working electrode 104 and the counter electrode 106, thereby suppressing electrical short circuits, while also allowing ions to pass through. As the separator 107, a cellulose membrane, a polymer, a composite material of polymer and ceramic, etc., can be used.

[0044] The electrolyte layer 108 is an immersion layer in which the working electrode 104, separator 107, and counter electrode 106 are immersed. For example, an ionic liquid can be used as the electrolyte layer 108. An ionic liquid is a salt of a liquid that is non-volatile at room temperature and pressure.

[0045] Furthermore, a power supply 109 is connected to the working electrode current collector 103 and the counter electrode current collector 105 of the electrochemical cell 101. The power supply 109 can apply a predetermined voltage to the working electrode 104 and the counter electrode 106, thereby changing the potential difference between the working electrode 104 and the counter electrode 106. The working electrode 104 is the negative electrode, and the counter electrode 106 is the positive electrode.

[0046] The electrochemical cell 101 operates in a carbon dioxide capture mode, in which carbon dioxide is captured at the working electrode 104, and in a carbon dioxide release mode, in which carbon dioxide is released from the working electrode 104, by changing the potential difference between the working electrode 104 and the counter electrode 106. The carbon dioxide capture mode is a charging mode that charges the electrochemical cell 101, and the carbon dioxide release mode is a discharge mode that discharges the electrochemical cell 101.

[0047] Specifically, in carbon dioxide capture mode, a first voltage V1 is applied between the working electrode 104 and the counter electrode 106, and electrons are supplied from the counter electrode 106 to the working electrode 104. At the first voltage V1, the working electrode potential is less than the counter electrode potential. The first voltage V1 can be, for example, in the range of 0.5 to 2.0 V.

[0048] In the carbon dioxide emission mode, a second voltage V2 is applied between the working electrode 104 and the counter electrode 106, supplying electrons from the working electrode 104 to the counter electrode 106. The second voltage V2 is different from the first voltage V1. The second voltage V2 only needs to be lower than the first voltage V1, and the relative magnitudes of the working electrode potential and the counter electrode potential are not limited. In other words, in the carbon dioxide emission mode, the working electrode potential may be less than the counter electrode potential, the working electrode potential may be equal to the counter electrode potential, or the working electrode potential may be greater than the counter electrode potential.

[0049] Next, the operation of the carbon dioxide capture system 1 will be explained. As described above, the carbon dioxide capture system 1 operates by alternately switching between carbon dioxide capture mode and carbon dioxide release mode. The operation of the carbon dioxide capture system 1 is controlled by the control device 14.

[0050] First, the operation of the carbon dioxide recovery system 1 in carbon dioxide recovery mode will be explained. In carbon dioxide recovery mode, the pump 11 is activated. This supplies the mixed gas to the carbon dioxide recovery device 10. In the carbon dioxide recovery device 10, the voltage applied between the working electrode 104 and the counter electrode 106 of the electrochemical cell 101 is defined as the first voltage V1. This allows for the simultaneous donation of electrons to the electroactivating auxiliary material of the counter electrode 106 and the withdrawal of electrons to the carbon dioxide adsorbent of the working electrode 104.

[0051] The carbon dioxide adsorbent on the working electrode 104, having received electrons from the counter electrode 106, has increased carbon dioxide binding affinity and adsorbs carbon dioxide contained in the mixed gas. As a result, the carbon dioxide recovery device 10 can recover carbon dioxide from the mixed gas. The mixed gas, after carbon dioxide has been removed, is discharged from the carbon dioxide recovery device 10.

[0052] In carbon dioxide recovery mode, the flow path switching valve 12 switches to a flow path that allows the mixed gas discharged from the carbon dioxide recovery device 10 to flow out to the atmosphere. As a result, the mixed gas discharged from the carbon dioxide recovery device 10 is released into the atmosphere.

[0053] Next, the operation of the carbon dioxide recovery system 1 in carbon dioxide release mode will be described. In carbon dioxide release mode, the pump 11 is stopped. This stops the supply of mixed gas to the carbon dioxide recovery device 10. In the carbon dioxide recovery device 10, the voltage applied between the working electrode 104 and the counter electrode 106 of the electrochemical cell 101 is set to the second voltage V2. This allows for simultaneous electron donation to the carbon dioxide adsorbent of the working electrode 104 and electron withdrawal to the electroactivating auxiliary material of the counter electrode 106.

[0054] The carbon dioxide adsorbent at the working electrode 104 releases electrons and enters an oxidized state. The carbon dioxide adsorbent's binding force to carbon dioxide decreases, and it desorbs and releases carbon dioxide. The carbon dioxide released from the carbon dioxide adsorbent is discharged from the carbon dioxide recovery device 10.

[0055] In carbon dioxide release mode, the flow path switching valve 12 switches to a flow path that allows carbon dioxide emitted from the carbon dioxide recovery device 10 to flow out to the inlet side of the carbon dioxide utilization device 13. As a result, the carbon dioxide emitted from the carbon dioxide recovery device 10 is supplied to the carbon dioxide utilization device 13.

[0056] As described above, the carbon dioxide recovery system 1 of this embodiment allows for the recovery of carbon dioxide from a mixed gas and the effective utilization of the recovered carbon dioxide.

[0057] In the carbon dioxide recovery device 10 configured as described above, as the mixed gas flows through the gas channels 102 between the stacked electrochemical cells 101, carbon dioxide is adsorbed from the mixed gas by the carbon dioxide adsorbent of the working electrode 104. Therefore, the carbon dioxide recovery capacity of the carbon dioxide recovery device 10 is strongly influenced by the flow of the mixed gas in each gas channel 102 (i.e., the channel shape of the gas channels 102).

[0058] As described above, since the gas channel 102 is formed between multiple electrochemical cells 101 arranged in a stacked configuration, warping or distortion of the electrochemical cells 101 can be considered factors that cause changes in the channel shape of the gas channel 102.

[0059] In the first embodiment, as a configuration to suppress warping and distortion of the electrochemical cell 101, the working electrode 104 and counter electrode 106, which are electrode films 200, are divided into a plurality of regions 110, and a suppression section 120 is placed adjacent to each region 110.

[0060] Here, a method for manufacturing an electrochemical cell 101, which includes an electrode film 200 (working electrode 104, counter electrode 106) containing multiple regions 110 and suppression portions 120, will be described with reference to Figure 4. The method for manufacturing the electrochemical cell 101 includes a manufacturing step for the electrode film 200 constituting the working electrode 104 and a manufacturing step for the electrode film 200 constituting the counter electrode 106. The manufacturing steps for the electrode film 200 constituting the working electrode 104 and the manufacturing steps for the electrode film 200 constituting the counter electrode 106 are basically equivalent and can be carried out separately.

[0061] Figure 4 illustrates a method for manufacturing the electrode film 200 that constitutes the working electrode 104. In the explanation in Figure 4, the working electrode current collector 103 is used as the base material 210 when manufacturing the electrode film 200 related to the working electrode 104. In this case, the base material 210 can be any flat plate-shaped member having a flat surface. For example, as will be described later, it is also possible to use the separator 107 as the base material 210.

[0062] As shown in Figure 4, the manufacturing process of the electrode film 200 related to the working electrode 104 includes a placement step, a coating step, a region formation step, and a drying step. In the placement step, a masking member 220 having multiple region openings 220a is placed on one surface of the working electrode current collector 103, which is the base material 210. The masking member 220 has multiple region openings 220a, each of which has an opening area smaller than the size of the electrochemical cell 101.

[0063] By placing the masking member 220, on one surface of the working electrode current collector 103, there is a portion where the surface of the working electrode current collector 103 is exposed (for example, the portion corresponding to the area opening 220a) and a portion covered by the masking member 220.

[0064] After the placement process is completed, the coating process is performed. In the coating process, paste 200a, which is a component of the electrode film 200, is applied to the working electrode current collector 103, which is the base material 210, and the masking member 220 placed on the base material 210. In this case, paste 200a is made by mixing the components of the working electrode 104, such as carbon dioxide adsorbent, conductive additive, and binder, into a paste. As a result, the paste 200a fills the interior of the multiple regional openings 220a formed in the masking member 220 and is applied to one side of the working electrode current collector 103.

[0065] After the coating process is completed, the region formation process is performed. In the region formation process, the masking member 220 is lifted upward and removed from the working electrode current collector 103 at the end of the coating process. As a result, paste 200a that has been filled into multiple region openings 230a remains on one surface of the working electrode current collector 103, thus forming an electrode film 200 having multiple regions 110.

[0066] In the region formation process, by removing the masking member 220, dividing lines 120a, where paste 200a is not applied to the surface of the working electrode current collector 103, are formed around the multiple regions 110 as suppression sections 120. The dividing lines 120a are formed along the opening edges of the multiple region openings 220a in the masking member 220. In the first embodiment, multiple dividing lines 120a are formed in a straight line extending along a predetermined direction.

[0067] In the drying process, the paste 200a applied to one surface of the working electrode current collector 103 is dried and hardened. As a result, a working electrode 104 is formed on one surface of the working electrode current collector 103, consisting of an electrode film 200 having multiple regions 110 and dividing lines 120a.

[0068] Furthermore, in the drying process, the substrate 210 and the paste 200a on the substrate 210 may be heated to speed up the drying process. Alternatively, the drying process may be divided into multiple stages. For example, a primary drying stage may be added before the region formation stage to advance the drying of the paste 200a, thereby improving the accuracy of removing the masking member 220 in the region formation stage.

[0069] Through the above process, in the manufacturing process of the electrode film 200 relating to the working electrode 104, the working electrode 104, consisting of the electrode film 200, is formed on one side of the working electrode current collector 103.

[0070] In this regard, the manufacturing process of the electrode film 200 relating to the counter electrode 106 also includes a placement step, a coating step, a region formation step, and a drying step. As a result, the counter electrode 106, consisting of the electrode film 200, is formed on one side of the counter electrode current collector 105. However, the paste 200a used in the coating step in this case is a paste made by mixing the constituent materials of the counter electrode 106, and contains an electroactivating agent, a conductive additive, and a binder.

[0071] Subsequently, a bonding process is performed. In the bonding process, the working electrode current collector 103 and working electrode 104, manufactured in the manufacturing process of the electrode film 200 related to the working electrode 104, and the counter electrode current collector 105 and counter electrode 106, manufactured in the manufacturing process of the electrode film 200 related to the counter electrode current collector 105, are bonded together with a separator 107 in between. When performing the bonding process, the electrolyte is impregnated into the working electrode current collector 103 and working electrode 104, and the counter electrode current collector 105 and counter electrode 106 by dropping the electrolyte onto them beforehand. Then, in the bonding process, as is clear from Figures 3 and 6, the materials are bonded together so that the surface on the counter electrode 106 side and the surface on the working electrode 104 side are in contact with the separator 107.

[0072] Subsequently, the power supply 109 is connected to the working electrode current collector 103 and the counter electrode current collector 105. This manufactures the electrochemical cell 101.

[0073] In the electrode film 200 manufactured in this manner, the suppression portion 120, which is configured as a dividing line 120a, is adjacent to multiple regions 110, thus suppressing warping of the electrode film 200. The number and arrangement of multiple regions 110 and dividing lines 120a in the electrode film are determined so that the curvature of the electrode film 200 is 1 mm or less.

[0074] Here, the curvature of the electrode film 200 is defined by Stoney's equation shown in Figure 5. According to Stoney's equation, when the curvature of the electrode film 200 is expressed as a function of stress and the coating size of the electrode film 200, the curvature of the electrode film 200 is proportional to the square of the coating size l of the electrode film 200, the internal stress σ of the electrode film 200, and the thickness d of the electrode film 200 to the power of 1. The curvature of the electrode film 200 is proportional to the Young's modulus Es of the substrate 210 to the power of -1 and the thickness b of the substrate 210 to the power of -2.

[0075] Since the electrode film 200 used in the electrochemical cell 101 is mainly made of carbon, the internal stress σ of the electrode film 200 tends to be large. Also, the thickness d of the electrode film 200 is large compared to electrodes used in batteries. Furthermore, since the working electrode current collector 103 used as the base material 210 has multiple working electrode openings formed to allow the mixed gas to pass through, the rigidity of the base material 210 is low, and the effective Young's modulus (i.e., the Young's modulus Es of the base material 210) tends to be low.

[0076] Therefore, considering the various conditions related to the electrode film 200 used in the electrochemical cell 101, it is clear that limiting the coating size l of the electrode film 200 is very effective in suppressing warping of the electrode film 200.

[0077] In the first embodiment, the electrode film 200 is divided into multiple regions 110 by dividing lines 120a which serve as gas flow paths 102, thereby sufficiently limiting the coating size l. As a result, the electrochemical cell 101 according to the first embodiment has a configuration that suppresses warping and allows for appropriate control of the width of the gas flow paths 102.

[0078] An example of the configuration of an electrochemical cell 101 having an electrode film 200 manufactured by the method for manufacturing the electrode film 200 according to the first embodiment will be described with reference to Figure 6.

[0079] As shown in Figure 4, in the manufacturing method of the electrode film 200 according to the first embodiment, an electrode film 200 (working electrode 104, counter electrode 106) having three regions 110 is formed on one surface of a substrate 210 (working electrode current collector 103, counter electrode current collector 105). A dividing line 120a, which serves as a suppression portion 120, is formed between the multiple regions 110. The dividing line 120a extends linearly along a predetermined direction.

[0080] In the configuration example shown in Figure 6, when bonding the surface on the counter electrode 106 side and the surface on the working electrode 104 side to the separator 107 during the bonding process described above, the dividing line 120a on the working electrode 104 side and the dividing line 120a on the counter electrode 106 side are bonded together so that they extend in the same direction.

[0081] Then, a spacer 300 is placed on the electrochemical cell 101 after the bonding process is complete to form a gas channel 102. As shown in Figure 6, the spacer 300 is positioned at the edge of the electrochemical cell 101 so as to be continuous in the same direction as the dividing line 120a.

[0082] Multiple electrochemical cells 101, configured as shown in Figure 6, are stacked inside the housing 100 to form the carbon dioxide recovery device 10 shown in Figure 7. In this configuration, the stack of electrochemical cells 101 is arranged such that each dividing line 120a in the electrochemical cells 101 aligns with the gas flow direction in the carbon dioxide recovery device 10.

[0083] By adopting this configuration, the curvature of the electrochemical cell 101 in the direction intersecting the gas flow direction can be suppressed by providing each dividing line 120a. On the other hand, the curvature of the electrochemical cell 101 in the direction of gas flow can be suppressed by spacers 300 that are continuous at the edge of the electrochemical cell 101 in a direction coinciding with the gas flow direction. Therefore, the carbon dioxide recovery device 10 shown in Figure 7 can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path due to the curvature of the electrochemical cell.

[0084] Furthermore, when manufacturing an electrode film 200 divided into multiple regions 110 by dividing lines 120a extending in a predetermined direction, various manufacturing methods can be employed in addition to the method using the masking member 220 described above. For example, a continuous molding process such as roll molding may be used to manufacture an electrode film 200 divided into multiple regions 110 by dividing lines 120a extending in a predetermined direction.

[0085] As described above, according to the carbon dioxide recovery system 1 of the first embodiment, in the electrochemical cell 101, multiple regions 110 can be formed in the electrode film 200 constituting the working electrode 104 and the counter electrode 106, and suppression sections 120 can be placed adjacent to each of them. By making the multiple regions 110 smaller than the size of the electrochemical cell 101 and forming suppression sections 120, warping of the electrode film 200 in the electrochemical cell 101 can be suppressed.

[0086] This makes it possible to suppress the warping of the electrochemical cell 101 and appropriately control the width of the gas flow path 102 arranged between the electrochemical cells 101. Therefore, the carbon dioxide recovery system 1 can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path 102 due to the warping of the electrochemical cell 101.

[0087] As shown in Figures 4, 6, and 7, in the carbon dioxide recovery system 1 according to the first embodiment, the suppression section 120 is composed of dividing lines 120a that divide the electrode film 200 into a plurality of regions 110. By dividing the plurality of regions 110 with the dividing lines 120a, the coating size l of the electrode film 200 can be reliably reduced, and the warping of the electrode film 200 can be effectively suppressed.

[0088] As shown in Figures 6 and 7, in the carbon dioxide recovery device 10, the electrochemical cell 101 is positioned such that the dividing line 120a, which acts as a suppression section 120, extends along the gas flow direction. This suppresses the curvature of the electrochemical cell 101 in the direction intersecting the gas flow direction, thereby maintaining the width of the gas flow path 102 and suppressing a decrease in the recovery capacity of carbon dioxide, which is the gas to be recovered.

[0089] As shown in Figure 4, according to the manufacturing method of the electrode film 200 of the first embodiment, an electrode film 200 having a plurality of regions 110 and suppression portions 120 can be efficiently manufactured by using a masking member 220 to perform a placement step, a coating step, a region formation step, and a drying step.

[0090] Furthermore, by using the electrode film 200 manufactured by this manufacturing method, it becomes possible to suppress the warping of the electrochemical cell 101 and appropriately control the width of the gas flow path 102 between the electrochemical cells 101. Accordingly, the carbon dioxide recovery system 1 using the electrode film 200 manufactured by this manufacturing method can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path 102 due to the warping of the electrochemical cell 101.

[0091] (Second Embodiment) Next, a second embodiment, which differs from the embodiment described above, will be explained with reference to Figure 8. In the second embodiment, the manufacturing method of the electrode film 200 constituting the working electrode 104 and the counter electrode 106, and the configuration of the suppression unit 120 differ from those of the first embodiment. Other basic configurations are the same as in the embodiment described above, so a further explanation will be omitted.

[0092] Furthermore, in the explanation of Figure 8, the method for manufacturing the electrode film 200 constituting the working electrode 104 will be described, similar to the first embodiment, and the working electrode current collector 103 will be used as the base material 210.

[0093] As shown in Figure 8, the manufacturing method of the electrode film 200 according to the second embodiment involves a coating step, a region formation step, a removal step, and a drying step. In the manufacturing method of the electrode film 200 according to the second embodiment, groove-shaped partition lines 120b are formed on the electrode film 200 as suppression parts 120, and the electrode film is divided into a plurality of regions 110 by the partition lines 120b.

[0094] Specifically, in the coating process of the second embodiment, paste 200a, which is a component of the electrode film 200, is applied to a predetermined area for forming the electrode film 200 on one surface of the working electrode current collector 103, which is the base material 210. In this case, paste 200a is made by mixing the components of the working electrode 104, such as a carbon dioxide adsorbent, a conductive additive, and a binder, to form a paste.

[0095] In the method for manufacturing the electrode film 200 according to the second embodiment, a region formation step is performed after the coating step is completed. In the region formation step according to the second embodiment, a suppression portion forming member 230 having a plurality of region openings 230a is used to form a plurality of regions 110 and partition lines 120b as suppression portions 120 in the coated paste 200a. The suppression portion forming member 230 has a plurality of region openings 230a, each of which has an opening area smaller than the size of the electrochemical cell 101.

[0096] To explain in more detail, in the region formation process, the suppression portion forming member 230 is pressed against the paste 200a applied to one surface of the working electrode current collector 103, and pressure is applied to bring it closer to the surface of the working electrode current collector 103.

[0097] As a result, a step is created in the paste 200a between the portion in contact with the suppression portion forming member 230 and the portion not in contact with the suppression portion forming member 230 (for example, the area opening 230a). As shown in Figure 8, the thickness of the paste 200a in the portion in contact with the suppression portion forming member 230 is reduced by the pressure, so a straight groove-like demarcation line 120b is formed.

[0098] On the other hand, even if the suppression portion forming member 230 is pressed against it, no pressure is applied to the paste 200a inside the region opening 230a. For this reason, multiple regions 110 in the electrode film 200 are formed inside each region opening 230a, and these regions are smaller than the size of the electrochemical cell 101.

[0099] By performing the region formation process using the suppression portion forming member 230, multiple regions 110 smaller than the size of the electrochemical cell 101, along with groove-shaped partition lines 120b adjacent to each region 110, can be formed as suppression portions 120.

[0100] After the region formation process is completed, a removal process is performed. In the removal process, any excess paste 200a that spilled out when the suppression portion forming member 230 was pressed against the paste 200a during the region formation process is removed. The removal process can also be described as a shaping process that adjusts the shape of each region 110 and the dividing line 120b in the electrode film 200 after the region formation process in the second embodiment has been completed.

[0101] In the drying process, the paste 200a applied to one surface of the working electrode current collector 103 is dried and hardened. As a result, a working electrode 104 is formed on one surface of the working electrode current collector 103, consisting of an electrode film 200 having multiple regions 110 and dividing lines 120b.

[0102] Furthermore, the drying process may be divided into multiple stages. For example, a primary drying stage may be added after the coating stage and before the region formation stage to advance the drying of the paste 200a. This allows for adjustment of the amount of deformation of the paste 200a when the suppression part forming member 230 is pressed against the paste 200a in the region formation stage, thereby improving the molding accuracy of the region 110 and the demarcation line 120b.

[0103] Through the above steps, a working electrode 104 is formed on one side of the working electrode current collector 103 by the manufacturing method according to the second embodiment, consisting of an electrode film 200 having a plurality of 110s and dividing lines 120b.

[0104] In the second embodiment as well, the manufacturing process for the electrode film 200 relating to the counter electrode 106 includes a coating step, a region formation step, a removal step, and a drying step. As a result, a counter electrode 106 having multiple regions 110 and dividing lines 120b is formed on one side of the counter electrode current collector 105. However, the paste 200a used in the coating step in this case is a paste made by mixing the constituent materials of the counter electrode 106, and includes an electroactivating agent, a conductive additive, and a binder.

[0105] In the carbon dioxide recovery system 1 according to the second embodiment, a partition line 120b is formed as a linearly extending groove in the electrode film 200 used in the carbon dioxide recovery system 1, which is a suppression portion 120.

[0106] The dividing line 120b is formed as a groove with a thickness smaller than that of the adjacent region 110 in terms of the electrode film 200. That is, since the dividing line 120b and each adjacent region 110 are integrated, the effect of suppressing the warping of the electrode film 200 is limited compared to the dividing line 120a in the first embodiment. However, considering the ease of dividing multiple regions 110 and the securing of basis weight, it is also conceivable to use the dividing line 120b as the suppression part 120.

[0107] As described above, according to the carbon dioxide recovery system 1 of the second embodiment, even when the electrode membrane 200 is divided into multiple regions 110 by groove-shaped dividing lines 120b, the effects and advantages obtained from the configuration and operation common to the above-described embodiment can be obtained.

[0108] Furthermore, according to the manufacturing method of the electrode film 200 as per the second embodiment, an electrode film 200 having multiple regions 110 and suppression portions 120 can be efficiently manufactured by performing a coating step, a region formation step, a removal step, and a drying step using a suppression portion forming member 230.

[0109] Furthermore, by using the electrode film 200 manufactured by this manufacturing method, it becomes possible to suppress the warping of the electrochemical cell 101 and appropriately control the width of the gas flow path 102 between the electrochemical cells 101. Accordingly, the carbon dioxide recovery system 1 using the electrode film 200 manufactured by this manufacturing method can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path 102 due to the warping of the electrochemical cell 101.

[0110] (Third embodiment) Next, a third embodiment, which differs from the embodiments described above, will be explained with reference to Figure 9. In the third embodiment, the method for manufacturing the electrode films 200 that constitute the working electrode 104 and the counter electrode 106 differs from that of the embodiments described above. Other basic configurations are the same as in the embodiments described above, so a further explanation will be omitted.

[0111] Furthermore, in the explanation of Figure 9, similar to the embodiment described above, the manufacturing method of the electrode film 200 constituting the working electrode 104 will be described, and the working electrode current collector 103 will be used as the base material 210.

[0112] As shown in Figure 9, the manufacturing method of the electrode film 200 according to the third embodiment involves a coating step, a primary drying step, a partitioning step, and a drying step. In the manufacturing method of the electrode film 200 according to the third embodiment, a dividing line 120a is formed on the electrode film 200 as a suppression part 120 by the removal device 240, and the electrode film 200 is divided into a plurality of regions 110 by the dividing line 120a.

[0113] Specifically, in the coating process of the third embodiment, similar to the second embodiment, paste 200a, which is a component of the electrode film 200, is applied to a predetermined area for forming the electrode film 200 on one surface of the working electrode current collector 103, which is the base material 210.

[0114] After the coating process according to the third embodiment is completed, a primary drying process is performed. In the primary drying process, the paste 200a applied to the substrate 210 is dried to the extent that a portion of the paste 200a can be removed by the removal device 240 in the partitioning process described later.

[0115] Once the primary drying process is complete, a partitioning process is performed. In the partitioning process in the third embodiment, a portion of the paste 200a that has been dried to a predetermined degree of dryness is removed from the substrate 210 using a removal device 240, thereby partitioning it into multiple regions 110.

[0116] Here, various devices can be used as the removal device 240, as long as they can remove a portion of the paste 200a applied to the substrate 210. For example, as an example of the removal device 240, a grinder or sander can be used to create a partitioning process by machining.

[0117] Furthermore, in the partitioning process shown in Figure 9, a portion of the paste 200a is removed by the removal device 240 to form a dividing line 120a as a suppression section 120. In the third embodiment, the dividing line 120a is configured to extend in multiple directions. This configuration makes it possible to suppress, for example, the curvature of the electrode film 200 in the direction perpendicular to the gas flow direction, as well as the curvature of the electrode film 200 in the direction of gas flow walking.

[0118] In the partitioning process of the third embodiment, the suppression section 120 is formed by removing a portion of the paste 200a with the removal device 240. The amount of paste 200a removed by the removal device 240 can be set as appropriate. As shown in Figure 9, if the entire thickness of the applied paste 200a is removed, a dividing line 120a is formed, and if a portion of the thickness of the applied paste 200a is removed, a groove-shaped partition line 120b is formed.

[0119] After the partitioning step according to the third embodiment is completed, a drying step is performed. In the drying step, the paste 200a applied to one surface of the working electrode current collector 103 is dried and hardened. As a result, a working electrode 104 is formed on one surface of the working electrode current collector 103, consisting of an electrode film 200 having a plurality of regions 110 and dividing lines 120a.

[0120] Through the above steps, a working electrode 104 is formed on one side of the working electrode current collector 103 by the manufacturing method according to the third embodiment, consisting of an electrode film 200 having a plurality of 110s and dividing lines 120a.

[0121] In the third embodiment as well, the manufacturing process for the electrode film 200 relating to the counter electrode 106 includes a coating step, a primary drying step, a partitioning step, and a drying step. As a result, a counter electrode 106 having a plurality of regions 110 and dividing lines 120a is formed on one side of the counter electrode current collector 105. However, the paste 200a used in the coating step in this case is a paste made by mixing the constituent materials of the counter electrode 106, and includes an electroactivating agent, a conductive additive, and a binder.

[0122] As described above, according to the carbon dioxide recovery system 1 of the third embodiment, even when a removal device 240 is used as the manufacturing method for the electrode film 200, the effects and advantages derived from the common configuration and operation of the above-described embodiment can be obtained.

[0123] Furthermore, according to the manufacturing method of the electrode film 200 as described in the third embodiment, an electrode film 200 having multiple regions 110 and suppression portions 120 can be efficiently manufactured by performing a coating step, a primary drying step, a partitioning step, and a drying step using a removal device 240.

[0124] Furthermore, by using the electrode film 200 manufactured by this manufacturing method, it becomes possible to suppress the warping of the electrochemical cell 101 and appropriately control the width of the gas flow path 102 between the electrochemical cells 101. Accordingly, the carbon dioxide recovery system 1 using the electrode film 200 manufactured by this manufacturing method can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path 102 due to the warping of the electrochemical cell 101.

[0125] (Fourth Embodiment) Next, a fourth embodiment, which differs from the embodiments described above, will be explained with reference to Figure 10. In the fourth embodiment, the method for manufacturing the electrode films 200 constituting the working electrode 104 and the counter electrode 106 differs from that of the embodiments described above. Other basic configurations are the same as in the embodiments described above, so a further explanation is omitted.

[0126] Furthermore, in the explanation of Figure 10, similar to the embodiment described above, the manufacturing method of the electrode film 200 constituting the working electrode 104 is described, and the working electrode current collector 103 is used as the base material 210.

[0127] As shown in Figure 10, the method for manufacturing the electrode film 200 according to the fourth embodiment involves a coating step and a drying step. In the method for manufacturing the electrode film 200 according to the fourth embodiment, in the coating step of paste 200a by dispenser 250, multiple regions 110 and suppression parts 120 are formed by controlling the movement of dispenser 250.

[0128] Specifically, in the coating step of the third embodiment, paste 200a, which is a component of the electrode film 200, is applied to a predetermined electrode film 200 formation area on one surface of the working electrode current collector 103, which is the base material 210, using a dispenser 250.

[0129] Here, the dispenser 250 is a device that precisely dispenses a quantitative amount of liquid material, and dispenses a predetermined amount of paste 200a as the liquid material to apply it to the surface of the substrate 210.

[0130] In the coating process according to the fourth embodiment, the operation of the dispenser 250 is controlled, and a predetermined amount of paste 200a is applied to one surface of the working electrode current collector 103, which serves as the substrate 210. The paste 200a applied to the surface of the substrate 210 in a predetermined amount constitutes one of the multiple regions 110 in the electrode film 200.

[0131] Furthermore, while the shape of the paste 200a when applied by the dispenser 250 may be disc-shaped as shown in Figure 10, various shapes can be used.

[0132] Then, after applying a predetermined amount of paste 200a, the dispenser 250 moves to a position that provides sufficient distance from the paste 200a already applied to the substrate 210, and applies a new predetermined amount of paste 200a.

[0133] As the application of the paste 200a by the dispenser 250 and the movement of the dispenser 250 are repeated within the electrode film 200 formation area on the substrate 210, multiple regions 110 arranged in a dot pattern are formed within the electrode film 200 formation area, as shown in Figure 10. In addition, between each region 110, areas where the paste 200a is not applied are formed as the dispenser 250 moves. These areas between each region 110 where the paste 200a is not applied function as suppression sections 120, similar to the dividing lines 120a.

[0134] After the coating process according to the fourth embodiment is completed, a drying process is performed. In the drying process, the dot-shaped paste 200a applied to the working electrode current collector 103 is dried and hardened. As a result, a working electrode 104 is formed on one surface of the working electrode current collector 103, consisting of an electrode film 200 having a plurality of regions 110 and suppression portions 120.

[0135] Through the above steps, a working electrode 104 is formed on one side of the working electrode current collector 103 by the manufacturing method according to the fourth embodiment, consisting of an electrode film 200 having a plurality of 110s and suppression portions 120.

[0136] In the fourth embodiment as well, the manufacturing process of the electrode film 200 relating to the counter electrode 106 includes a coating step using a dispenser 250 and a drying step. This forms a counter electrode 106 having a plurality of regions 110 and a suppression portion 120 on one side of the counter electrode current collector 105. However, the paste 200a used in the coating step in this case is a paste made by mixing the constituent materials of the counter electrode 106, and includes an electroactivating auxiliary, a conductive additive, and a binder.

[0137] As described above, according to the carbon dioxide recovery system 1 of the fourth embodiment, even when multiple regions 110 and suppression sections 120 are formed in the coating process using the dispenser 250, the effects and advantages derived from the common configuration and operation of the above-described embodiments can be obtained.

[0138] Furthermore, according to the manufacturing method of the electrode film 200 according to the fourth embodiment, an electrode film 200 having multiple regions 110 and suppression portions 120 can be efficiently manufactured by performing a coating step and a drying step using a dispenser 250.

[0139] Furthermore, by using the electrode film 200 manufactured by this manufacturing method, it becomes possible to suppress the warping of the electrochemical cell 101 and appropriately control the width of the gas flow path 102 between the electrochemical cells 101. Accordingly, the carbon dioxide recovery system 1 using the electrode film 200 manufactured by this manufacturing method can suppress the decrease in the recovery capacity of the target gas caused by changes in the gas flow path 102 due to the warping of the electrochemical cell 101.

[0140] (Fifth embodiment) Next, a fifth embodiment, which differs from the embodiments described above, will be described with reference to Figure 11. In the embodiments described above, an electrode film 200 was formed on one side of the working electrode current collector 103 and the counter electrode current collector 105, which are the base material 210. However, it is also possible to use a separator 107 as the base material 210. Therefore, in the fifth embodiment, an embodiment in which a separator 107 is used as the base material 210 will be described. Other basic configurations are the same as in the embodiments described above, so a further explanation will be omitted.

[0141] As described in the above-mentioned embodiment regarding the bonding process, and as shown in Figures 3, 6, and 7, the electrochemical cell 101 is configured such that the working electrode 104 is in contact with one surface of the separator 107, and the counter electrode 106 is in contact with the other surface of the separator 107.

[0142] Therefore, one side of the separator 107 can be used as the base material 210 for the manufacturing process of the electrode film 200 related to the working electrode 104, and the other side of the separator 107 can be used as the base material 210 for the manufacturing process of the electrode film 200 related to the counter electrode 106.

[0143] Furthermore, for the manufacturing process of the electrode film 200 related to the working electrode 104 and the manufacturing process of the electrode film 200 related to the counter electrode 106, either of the methods for manufacturing the electrode film 200 described in the above-described embodiment may be adopted.

[0144] When manufacturing electrode films 200 on both sides of the separator 107 (i.e., one side and the other side), it is anticipated that the electrode films 200 may warp on one side or the other side due to differences in thickness d and internal stress σ of the electrode films 200.

[0145] In this case, with respect to the electrode films 200 on one side and the other side of the separator 107, it is preferable to form a plurality of regions 110 and suppression portions 120 on the electrode film 200 on one side based on the thickness d of the electrode film 200 and the relative magnitudes of the internal stress σ of the electrode film 200.

[0146] Regarding the thickness d of the electrode film 200, it is preferable to form multiple regions 110 and suppression portions 120 in the electrode film 200 with a larger thickness d than the electrode film 200 on one side and the other side of the separator 107.

[0147] Furthermore, regarding the internal stress σ of the electrode film 200, it is preferable to form multiple regions 110 and suppression portions 120 in the electrode film 200 on the side with the larger internal stress σ, with respect to the electrode film 200 on one side and the other side of the separator 107.

[0148] As described above, according to the carbon dioxide recovery system 1 of the fifth embodiment, even when the separator 107 is used as the substrate 210 and electrode films 200 are manufactured on both sides of the substrate 210, the effects and advantages derived from the common configuration and operation of the above-described embodiments can be obtained.

[0149] (Other embodiments) The present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit of the invention. Furthermore, the means disclosed in each of the above embodiments may be combined as appropriate to the extent that they are feasible.

[0150] (a) In the embodiments described above, an example was given in which the gas recovery system according to the disclosure is applied to a carbon dioxide recovery system 1 that recovers carbon dioxide from a mixed gas. However, the application of the gas recovery system according to the disclosure is not limited to this. The gas recovery system according to the disclosure may also be applied to a system that recovers specific types of gases other than carbon dioxide from a mixed gas. For example, nitrogen oxide gas (NOx) and sulfur oxide gas (SOx) can be used as the gas to be recovered in the gas recovery system.

[0151] (b) Alternatively, at least one of the working electrode 104 and the counter electrode 106 of the electrochemical cell 101 may be made using an electrode film 200 having the plurality of regions 110 and suppression portion 120 described above.

[0152] (c) Furthermore, the shapes of the multiple regions 110 in the electrode film 200 according to this disclosure are not limited to the shapes shown in the embodiments described above. Any shape smaller than the size of the electrochemical cell 101 is acceptable, and there may be multiple types of shapes and sizes.

[0153] (d) In the embodiments described above, the suppression section 120 is shown as a dividing line 120a and a partition line 120b, but various shapes can be adopted. For example, the width of the dividing line 120a may be changed depending on its position in the electrochemical cell 101. Also, the thickness of the partition line 120b may be changed depending on its position in the electrochemical cell 101.

[0154] (e) Furthermore, the following steps can be adopted as the process for manufacturing the electrode film 200. For example, first, a placement step, a coating step, and a region formation step are performed on the film or release paper. That is, a state is created in which a paste 200a containing a plurality of regions 110 and suppression parts 120 is applied to the surface of the film or release paper. Next, the paste 200a on the film or release paper is dried with a substrate such as a current collector or separator in contact with it. After the paste 200a has dried, the film or release paper is peeled off. This makes it possible to form an electrode film 200 having a plurality of regions 110 and suppression parts 120 on the surface of the substrate 210.

[0155] (f) In the fifth embodiment described above, the electrode film 200 was formed by applying paste 200a to both sides (front and back) of the separator 107, but the embodiment is not limited to this. That is, the electrode film 200 may be formed by applying paste 200a to one side (either the front or back) of the separator 107. [Explanation of Symbols]

[0156] 1. Carbon dioxide capture system 101 Electrochemical cell 102 Gas flow path 104 Working electrode 106 Opposite 110 area 120 Inhibition section 200 electrode film 210 Substrate

Claims

1. A gas recovery system that recovers a target gas from a mixed gas by an electrochemical reaction, An electrochemical cell (101) comprising a working electrode (104) containing an adsorbent for adsorbing the gas to be recovered, and a counter electrode (106) that exchanges electrons with the working electrode, wherein when a voltage is applied between the working electrode and the counter electrode, electrons are supplied from the counter electrode to the working electrode, and the adsorbent adsorbs the gas to be recovered in response to the supply of electrons, A spacer (300) is placed between a plurality of the electrochemical cells arranged in a stack, and is used to provide a gap between the plurality of electrochemical cells in the direction in which they are stacked. A gas channel (102) formed between a plurality of stacked electrochemical cells and the spacer through which the mixed gas flows is included, At least one of the working electrode and the counter electrode is composed of an electrode film (200), The electrode film has a plurality of regions (110) smaller than the size of the electrochemical cell, Multiple of the aforementioned regions are adjacent to each other, with suppression portions (120, 120a, 120b) for suppressing warping of the electrode film. The suppression portion is a gas recovery system in which the electrode film is not formed or is formed linearly with a film thickness smaller than the film thickness of the plurality of regions.

2. The gas recovery system according to claim 1, wherein the suppression portion extends along the flow direction of the mixed gas flowing through the gas passage.

3. An electrochemical cell (101) comprising a working electrode (104) containing an adsorbent material for adsorbing the gas to be recovered contained in the mixed gas, and a counter electrode (106) that exchanges electrons with the working electrode, wherein when a voltage is applied between the working electrode and the counter electrode, electrons are supplied from the counter electrode to the working electrode, and the adsorbent material adsorbs the gas to be recovered in response to the supply of electrons, A method for manufacturing an electrode film (200) that constitutes at least one of the working electrode and the counter electrode, used in a gas recovery system that recovers the target gas from the mixed gas by an electrochemical reaction, comprising: a gas channel (102) formed between a plurality of stacked electrochemical cells through which the mixed gas flows; A mounting step in which a masking member (220) having multiple openings (220a) is placed on a base material (210), A coating step of applying the constituent material (200a) of the electrode film to the substrate and the masking member, After completing the coating step, the masking member is removed to form a region formation step in which a plurality of regions (110) smaller than the size of the electrochemical cell and a suppression portion (120) adjacent to the regions for suppressing warping of the electrode film are formed. A method for manufacturing an electrode film used in a gas recovery system, comprising a drying step of drying the constituent materials of the electrode film coated on the substrate.

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