Cell stack, method for producing cell stack system, hot module, and gas manufacturing apparatus

Abstract

To provide a cell stack capable of significantly reducing labor involved in adjusting a pressure loss between an upstream side and a downstream side of the cell stack.SOLUTION: A cell stack 1 comprising a plurality of electrochemical single cells 10 each including a solid electrolyte layer 12, an air electrode 14, and a fuel electrode 16, comprises: a first supply passage for supplying gas to a fuel chamber; a first exhaust passage for exhausting the gas from the fuel chamber; a second supply passage for supplying gas to an air chamber; and a second exhaust passage for exhausting the gas from the air chamber. Pressure loss characteristic information is displayed on the cell stack 1 at a position visible from an exterior, the pressure loss characteristic information including, for each of a plurality of operation modes distinguished according to a type of gas to be generated, at least one of a first pressure loss amount from an end of the first supply passage to an end of the first exhaust passage and a second pressure loss amount from an end of the second supply passage to an end of the second exhaust passage when the cell stack 1 is operated by each operation mode.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cell stack including a plurality of solid oxide electrochemical unit cells, a method for manufacturing a cell stack system, a hot module, and a gas production device. [Background technology]

[0002] Conventionally, cell stack systems comprising one or more cell stacks have been known. The multiple solid oxide electrochemical unit cells that make up the cell stack are characterized by performing electrochemical reactions with high efficiency in high-temperature environments, and are broadly classified into solid oxide electrolysis cells (SOECs) and solid oxide fuel cells (SOFCs) (hereinafter, multiple electrochemical unit cells will also be referred to as "electrochemical cells"). SOECs have the function of decomposing gases using electrical energy, while SOFCs have the function of generating electrical energy by combining multiple different gases. When the electrochemical cells are used as SOECs, the cell stack system functions as an electrolyzer, and when the electrochemical cells are used as SOFCs, the cell stack system functions as a power generation device.

[0003] In a cell stack system having multiple cell stacks, each cell stack is connected in parallel to a gas supply pipe and an exhaust pipe. Specifically, each cell stack is connected to the supply pipe by an upstream branch pipe, and each cell stack is connected to the exhaust pipe by a downstream branch pipe. As a result, gas (supply gas) introduced into the supply pipe is distributed and supplied to the corresponding cell stacks via the multiple upstream branch pipes. Gas (exhaust gas) exhausted from these cell stacks is combined in the exhaust pipe via the corresponding downstream branch pipes and then recovered. To efficiently operate such a cell stack system, it is desirable to appropriately control the distribution of the supply gas distributed and supplied to each cell stack. This is true whether the cell stack system is used for an electrolyzer or a power generator.

[0004] One method for controlling the distribution of supply gas is to install a flow regulator in each upstream branch pipe. However, this method complicates management of the cell stack system and is therefore impractical. Another problem is that heat-resistant flow regulators are expensive, which increases the manufacturing costs of the system.

[0005] Therefore, as another method for controlling the distribution of supply gas without using a flow regulator, a pressure loss adjustment component (typically an orifice) can be installed in the downstream branch pipe as needed to adjust the pressure difference (pressure loss) between the upstream and downstream sides of the cell stack. Here, cell stacks have pressure loss due to their internal structure, and the amount of pressure loss varies from cell stack to cell stack. Additionally, the amount of pressure loss in a cell stack also varies depending on the operating conditions of the cell stack system (e.g., the volumetric flow rate of the supply gas and the temperature of the cell stack). Therefore, to control the distribution of supply gas using this method, the cell stack system must be operated under actual operating conditions and the amount of pressure loss in each cell stack must be measured before installing the pressure loss adjustment component. Then, the pressure loss adjustment component must be selected or adjusted for each cell stack, taking into account the amount of pressure loss.

[0006] Non-Patent Document 1 describes that when the pressure loss of each cell stack in a cell stack system varies significantly, an orifice is introduced to equalize the gas flow rate. However, as is clear from the above description, this method requires significant time and effort to measure the pressure loss as the number of cell stacks increases, resulting in a significant increase in the effort required for pressure loss adjustment. This problem becomes more pronounced when the cell stack system is operated reversibly. In other words, in reversible operation, the pressure loss must be measured under the operating conditions of each operating mode, effectively doubling the time and effort required for the measurement work, further increasing the effort required for pressure loss adjustment. Note that reversible operation is an operation in which the electrochemical cell can be switched between an operating mode in which it is used as an SOEC and an operating mode in which it is used as an SOFC. For these reasons, there is a need for technology that can reduce the effort required for pressure loss adjustment. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Yoshinobu Takagi and seven others, "Development of Industrial Power Generation Devices Using Solid Oxide Fuel Cells," Hitz Technical Report, September 2015, Vol. 76, No. 1, pp. 11-15 Summary of the Invention

[0008] The present invention has been made to address the above-mentioned problems. That is, one of the objects of the present invention is to provide a technology that can significantly reduce the effort required to adjust the pressure loss between the upstream and downstream sides of a cell stack.

[0009] The cell stack (1) according to the present invention comprises: The device includes a plurality of solid oxide electrochemical unit cells (10), each including a solid electrolyte layer (12), an air electrode (14) stacked on the front side of the solid electrolyte layer, and a fuel electrode (16) stacked on the back side of the solid electrolyte layer. This cell stack is a first supply path (Pfi) for supplying gas to a fuel chamber (Sf), which is a space on the fuel electrode side in the cell stack; a first exhaust passage (Pfo) for exhausting gas from the fuel chamber; a second supply path (Pai) for supplying gas to an air chamber (Sa), which is a space on the air electrode side in the cell stack; A second exhaust path (Pao) for exhausting gas from the air chamber; Equipped with Pressure loss characteristic information including, for each operating mode, at least one of a first pressure loss amount, which is the amount of pressure loss from the end (Efi) of the first supply path (Pfi) to the end (Efo) of the first discharge path (Pfo), and a second pressure loss amount, which is the amount of pressure loss from the end (Eai) of the second supply path (Pai) to the end (Eao) of the second discharge path (Pao), when the cell stack (1) is operated in each of a plurality of operating modes distinguished according to the type of gas generated, is displayed in a position visible from the outside.

[0010] This cell stack has pressure loss characteristic information printed in a position visible from the outside. The pressure loss characteristic information includes, for each operating mode, at least one of a first pressure loss amount (the amount of pressure loss from the end of the first supply passage connected to the fuel chamber to the end of the first discharge passage) and a second pressure loss amount (the amount of pressure loss from the end of the second supply passage connected to the air chamber to the end of the second discharge passage). This allows workers at the cell stack delivery site to easily obtain the pressure loss amount of the cell stack simply by referring to the pressure loss characteristic information printed on the cell stack. In other words, this eliminates the need to measure the pressure loss amount and the need to operate the cell stack system for the purpose of measurement. This significantly reduces the time and effort required to obtain the pressure loss amount, and as a result, significantly reduces the effort required to adjust the pressure loss between the upstream and downstream sides of the cell stack.

[0011] In particular, when manufacturing a cell stack system having multiple cell stacks, the amount of pressure loss can be obtained before the cell stacks are assembled (i.e., connected with piping), and the relative positional relationship (layout) of the cell stacks can be determined based on the multiple obtained amounts of pressure loss. This allows for efficient use of pressure loss adjustment components, further reducing the effort required for adjusting pressure loss.

[0012] In addition, since the pressure loss characteristic information includes the amount of pressure loss for each operation mode, the amount of pressure loss for each operation mode can be appropriately acquired even in the case of reversible operation.Furthermore, since the pressure loss characteristic information includes the amount of pressure loss for multiple operation modes, the versatility of the cell stack can be maintained.

[0013] In one aspect of the invention, the first pressure loss amount includes a pressure loss amount that depends on a volume flow rate of the first supply gas supplied from the first supply path (Pfi) and a temperature of the cell stack (1), The second pressure loss amount includes a pressure loss amount that depends on the volume flow rate of the second supply gas supplied from the second supply passage (Pai) and the temperature.

[0014] Generally, the first pressure loss amount depends on the volumetric flow rate of the first supply gas and the temperature of the cell stack, and the second pressure loss amount depends on the volumetric flow rate of the second supply gas and the temperature of the cell stack. Therefore, with the above configuration, the accuracy of the first and second pressure loss amounts is improved, and as a result, the reliability of the pressure loss characteristic information is ensured.

[0015] In one aspect of the invention, In an operation mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell (10), the first pressure loss amount includes a pressure loss amount that depends on at least one of an applied current, a volumetric flow rate ratio of a gas to be electrolyzed that is contained in a first supply gas supplied from the first supply path (Pfi) to the first supply gas, an effective utilization rate of the gas to be electrolyzed, and a leakage amount of the first supply gas; The second pressure loss amount includes a pressure loss amount that depends on at least one of the applied current and the leakage amount of the second supply gas supplied from the second supply path (Pai). In an operation mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell, the first pressure loss amount includes a pressure loss amount that depends on at least one of an amount of power generation in a predetermined time, an effective utilization rate of a first compound target gas that is contained in the first supply gas and is a target for compounding, and an amount of leakage of the first supply gas, The second pressure loss amount includes a pressure loss amount that depends on at least one of the amount of power generation, the effective utilization rate of the second compound target gas that is contained in the second supply gas and is the target of compounding, and the amount of leakage of the second supply gas.

[0016] Generally, when each electrochemical unit cell is used as an electrolysis unit cell, the first pressure loss amount depends on the "current applied to the cell stack," the "volumetric flow rate ratio of the gas to be electrolyzed to the first supply gas (in other words, the concentration of the gas to be electrolyzed)," the "effective utilization rate of the gas to be electrolyzed," and the "leakage amount of the first supply gas (in other words, the volumetric flow rate of the first supply gas leaking outside the cell stack)." The second pressure loss amount depends on the "current applied to the cell stack" and the "leakage amount of the second supply gas." Therefore, with the above configuration, the accuracy of the first and second pressure loss amounts when the cell stack system functions as an electrolysis device is improved, and as a result, the reliability of the pressure loss characteristic information is ensured.

[0017] Furthermore, generally, when each electrochemical unit cell is used as a unit fuel cell, the first pressure loss amount depends on the "power generation amount of the cell stack in a predetermined time," the "effective utilization rate of the first compound target gas," and the "leakage amount of the first supply gas." The second pressure loss amount depends on the "power generation amount of the cell stack in a predetermined time," the "effective utilization rate of the second compound target gas," and the "leakage amount of the second supply gas." Therefore, with the above configuration, the accuracy of the first and second pressure loss amounts when the cell stack system functions as a power generation device is improved, and as a result, the reliability of the pressure loss characteristic information is ensured.

[0018] In one aspect of the invention, The operation mode is a first mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate hydrogen; a second mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate carbon monoxide; a third mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to produce a synthesis gas comprising hydrogen and carbon monoxide; a fourth mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell for generating water vapor; It includes at least one mode of:

[0019] According to this configuration, by referring to the pressure loss characteristic information, it is possible to easily obtain the amount of pressure loss in one of the first to fourth modes that is included in the operation mode.

[0020] In one aspect of the invention, The pressure loss characteristic information is provided in a format that can be read using an external device.

[0021] According to this configuration, by reading out the pressure loss characteristic information using an external device, the amount of pressure loss can be acquired (confirmed) even at a location away from the cell stack assembly site, improving convenience.

[0022] In one aspect of the invention, The form is a two-dimensional bar code (20).

[0023] According to this configuration, the pressure loss characteristic information can be compactly displayed on the cell stack.

[0024] A method for manufacturing a cell stack system including a plurality of the cell stacks according to the present invention includes the steps of: preparing the plurality of cell stacks (1); acquiring the pressure drop characteristic information listed on each of the plurality of cell stacks; determining a relative positional relationship between the plurality of cell stacks based on the acquired pressure loss characteristic information; Includes:

[0025] This configuration allows the relative positional relationship (layout) to be determined taking advantage of the individual differences in pressure loss of each cell stack, thereby enabling the efficient use of pressure loss adjustment components and further reducing the effort required for adjusting pressure loss.

[0026] The hot module (41) according to the present invention comprises: One or more of the cell stacks (1); a heat exchanger (43) for exchanging heat with the gas supplied to the cell stack; a heater (44) for heating the cell stack; a heat insulating material (45) in which the cell stack, the heat exchanger, and the heater are disposed; Equipped with.

[0027] The gas production device (40) according to the present invention comprises: The hot module (41) is used in an operation mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell (10).

[0028] In the above description, in order to facilitate understanding of the invention, the symbols used in the embodiments are added in parentheses to the constituent elements of the invention corresponding to the embodiments, but each constituent element of the invention is not limited to the embodiments defined by the symbols. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a perspective view of a cell stack of a solid oxide electrochemical cell according to an embodiment of the present invention. FIG. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] 2 is a cross-sectional view in the thickness direction of a single cell included in the electrochemical unit of FIG. 1. FIG. [Figure 4]FIG. 1 is a block diagram of a cell stack system. [Figure 5] FIG. 1 is a block diagram of a hydrogen production device equipped with a hot module. DETAILED DESCRIPTION OF THE INVENTION

[0030] A cell stack, a cell stack system manufacturing method, a hydrogen production device, and a hot module according to embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a cell stack 1, and FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. As shown in FIGS. 1 and 2, the cell stack 1 includes an electrochemical unit group formed by stacking a plurality of rectangular flat-plate-shaped electrochemical units U in the thickness direction (vertical direction), and a pair of end plates 2, 3 disposed on the upper and lower surfaces of the electrochemical unit group. In this embodiment, the upper side corresponds to an example of the "front side," and the lower side corresponds to an example of the "rear side." The electrochemical unit U is the smallest unit of an electrochemical device. The electrochemical device includes an electrolyzer and a power generator. The end plates 2, 3 are rectangular flat-plate-shaped members having the same outer shape as the electrochemical unit U and each have a rectangular opening formed in its center. The electrochemical unit group and the end plates 2, 3 are fastened to each other at their four corners by bolts B inserted through the end plates 2, 3 in the thickness direction and nuts (not shown). The end plates 2 and 3 are made of metal (for example, stainless steel). A QR code (registered trademark) 20 is printed on the top surface of the end plate 2 as a two-dimensional code. The QR code 20 contains pressure drop characteristic information of the cell stack 1 (described later). When each electrochemical unit U functions as an electrolyzer, the end plates 2 and 3 serve as an anode and a cathode, respectively, and when each electrochemical unit U functions as a fuel cell, the end plates 2 and 3 serve as a positive electrode and a negative electrode, respectively. For ease of explanation, the proportions of the components in the drawings may differ from the actual proportions.

[0031] The electrochemical unit U will be described in detail with reference to Fig. 2. As shown in Fig. 2, the electrochemical unit U includes a single cell 10, an interconnector 4, a separator 5, an air electrode frame 6, an anode frame 7, and a current collector 8.

[0032] The unit cell 10 is the smallest unit of a solid oxide electrochemical cell (i.e., an electrochemical unit cell), and includes a solid electrolyte layer 12, an air electrode 14 laminated on the upper surface of the solid electrolyte layer 12, and an anode 16 laminated on the lower surface of the air electrode 14. The air electrode 14 has a smaller outer shape than the solid electrolyte layer 12 and the anode 16, and is disposed in the center of the upper surface of the solid electrolyte layer 12 when viewed from above. Therefore, the upper surface of the outer periphery of the solid electrolyte layer 12 is exposed to the outside.

[0033] The interconnector 4 is a rectangular metal (e.g., stainless steel) member having a rectangular current collecting portion 4a that protrudes downward from the center of its lower surface. A pair of interconnectors 4 is arranged on both sides of the unit cell 10 in the thickness direction. Two adjacent electrochemical units U share one interconnector 4. In other words, the interconnector 4 also functions as a separator that separates the two adjacent electrochemical units U. The lower surface of the current collecting portion 4a is in contact with the upper surface of the air electrode 14 of the unit cell 10. The lower electrochemical unit U has a pair of interconnectors 4, 9 instead of a pair of interconnectors 4, 4. The interconnector 9 is arranged at the bottom end of the cell stack 1 and differs from the interconnector 4 in that it does not have a current collecting portion 4a.

[0034] The separator 5 is a rectangular plate-shaped metal (e.g., stainless steel) member with a rectangular opening formed in the center thereof. The periphery of the opening of the separator 5 is brazed to the upper surface of the outer periphery of the solid electrolyte layer 12 of the unit cell 10 with a brazing material (e.g., Ag brazing) not shown.

[0035] The air electrode frame 6 is a rectangular plate-shaped insulating member and may be formed of, for example, a mica sheet. A rectangular opening is formed in the center of the air electrode frame 6. The air electrode frame 6 is disposed so as to be interposed between the interconnector 4 (strictly speaking, the upper interconnector in the electrochemical unit U) and the separator 5.

[0036] The fuel electrode frame 7 is a rectangular plate-shaped metal (e.g., stainless steel) member with a square opening formed in the center. The fuel electrode frame 7 is disposed between the separator 5 and the interconnector 4 (strictly speaking, the lower interconnector in the electrochemical unit U).

[0037] The internal space of the electrochemical unit U is partitioned into an air chamber Sa and a fuel chamber Sf. The air chamber Sa is a space that allows the flow of "gas generated at the air electrode 14" and / or "gas supplied to the air chamber Sa". The air chamber Sa is composed of an upper interconnector 4, a separator 5, an air electrode frame 6, and a single cell 10. The fuel chamber Sf is a space that allows the flow of "gas generated at the fuel electrode 16" and / or "gas supplied to the fuel chamber Sf". The fuel chamber Sf is composed of a separator 5, a lower interconnector 4, an anode frame 7, and a single cell 10. The air chamber Sa and the fuel chamber Sf will be described later.

[0038] The current collector 8 is a rectangular porous member made of metal (for example, nickel) that is smaller than the fuel electrode 16 in a plan view and allows hydrogen or carbon monoxide to pass through. The current collector 8 is arranged in the fuel chamber Sf so as to be in contact with the lower surface of the fuel electrode 16 and the upper surface of the lower interconnector 4. Two adjacent unit cells 10 are stacked in the thickness direction so as to share the interconnector 4 via the current collector 8, thereby electrically connecting the unit cells 10 in series.

[0039] 1 and 2, four paths Pfi, Pfo, Pai, and Pao are formed as gas flow paths on the outer periphery of the cell stack 1. These paths Pfi, Pfo, Pai, and Pao are all formed to penetrate in the thickness direction through members of the cell stack 1 excluding the "end plate 2" and the "interconnector 4 above the upper electrochemical unit U at the upper end." Therefore, the ends Efi, Efo, Eai, and Eao of these paths Pfi, Pfo, Pai, and Pao all open at the lower surface of the end plate 3.

[0040] The path Pfi is formed along a side E1, which is one of the four sides that make up the outer periphery of the cell stack 1, near one corner of the side E1. The path Pfo is formed along a side E2 that faces the side E1, near the other corner of the side E2 (the corner located diagonally from the one corner of the side E1). As shown in FIG. 2, the path Pfi communicates with the fuel chamber Sf via a horizontal hole 7a formed in the fuel electrode frame 7 of each electrochemical unit U. The path Pfo communicates with the fuel chamber Sf via a horizontal hole 7b formed in the fuel electrode frame 7 of each electrochemical unit U. The "path Pfi" and the "path Pfo" are examples of a "first supply path" and a "first discharge path," respectively.

[0041] Path Pai is formed along side E2 near one corner of side E2. Path Pao is formed along side E1 near the other corner of side E1. Path Pai and path Pao are each connected to the air chamber Sa via a horizontal hole (not shown) formed in the air electrode frame 6 of each electrochemical unit U. "Path Pai" and "path Pao" are examples of a "second supply path" and a "second discharge path," respectively.

[0042] Next, the configuration of the unit cell 10 will be described in more detail with reference to Fig. 3. Fig. 3 is a cross-sectional view of the unit cell 10 in the thickness direction. As shown in Fig. 3, the solid electrolyte layer 12 is a rectangular flat layer measuring 150 mm square and 6 µm thick, and is configured to contain YSZ (yttria-stabilized zirconia). The solid electrolyte layer 12 has high oxide ion conductivity.

[0043] The cathode 14 is a rectangular, flat layer with a thickness of 108 μm, and is configured to contain a perovskite oxide such as lanthanum strontium cobalt iron oxide (LSCF). The cathode 14 has a functional layer and a current collecting layer (not shown). The current collecting layer is thicker than the functional layer and is disposed on top of the functional layer. The cathode 14 has high electronic conductivity, and effectively collects electrons from the current collecting layer.

[0044] The anode 16 is a rectangular, flat layer measuring 150 mm on each side, and is formed to have a thickness greater than that of the solid electrolyte layer 12 and the air electrode 14, 400 μm in this embodiment. That is, the unit cell 10 is an anode-supported cell in which the solid electrolyte layer 12 and the air electrode 14 are supported by the anode 16. The anode 16 has a support layer 18a and a functional layer 18b. The support layer 18a is significantly thicker than the functional layer 18b. The functional layer 18b is laminated and disposed between the upper surface of the support layer 18a and the lower surface of the solid electrolyte layer 12.

[0045] The support layer 18a is a cermet of nickel and YSZ, and is configured to be porous, including a plurality of micropores (not shown). The diameter of the micropores is on the order of several μm, which ensures permeability for water vapor and / or carbon dioxide. The functional layer 18b is similar to the support layer 18a in that it is a cermet of nickel and YSZ, but differs from the support layer 18a in that it is formed more densely than the support layer 18a. The fuel electrode 16 has high electronic conductivity.

[0046] The cell stack 1 is configured to be operable in a plurality of operation modes. The operation modes include an "operation mode in which each unit cell 10 is used as an electrolysis unit cell" and an "operation mode in which each unit cell 10 is used as a fuel cell unit cell." Here, an electrolysis unit cell is the smallest unit of an SOEC, and a fuel cell unit is the smallest unit of an SOFC. An electrolysis unit cell produces (generates) gas by electrolyzing a gas to be electrolyzed (gas to be electrolyzed) supplied to the fuel chamber Sf. A fuel cell unit generates electricity by combining gases to be combined (gases to be combined) supplied to the fuel chamber Sf and the air chamber Sa, respectively.

[0047] In this embodiment, three types of gases to be electrolyzed are used: "water vapor," "carbon dioxide," and a "mixed gas of water vapor and carbon dioxide." Hydrogen and oxygen are used as the gas to be combined. Hereinafter, the operating modes when the gas to be electrolyzed is water vapor, carbon dioxide, or a mixed gas of water vapor and carbon dioxide are referred to as the "water vapor electrolysis mode," the "carbon dioxide electrolysis mode," or the "co-electrolysis mode," respectively. The operating mode when the gas to be combined is hydrogen and oxygen is referred to as the "fuel cell mode." In the water vapor electrolysis mode, hydrogen is produced by electrolyzing water vapor into hydrogen and oxygen. In the carbon dioxide electrolysis mode, carbon monoxide is produced by electrolyzing carbon dioxide into carbon monoxide and oxygen. In the co-electrolysis mode, a synthesis gas containing hydrogen and carbon monoxide is produced by electrolyzing the mixed gas. In the fuel cell mode, water vapor is produced while electricity is generated. Therefore, the water vapor electrolysis mode, the carbon dioxide electrolysis mode, the co-electrolysis mode, and the fuel cell mode can also be referred to as "operating modes distinguished according to the type of gas produced." These operation modes correspond to examples of a "first mode," a "second mode," a "third mode," and a "fourth mode," respectively.

[0048] The operation of the cell stack 1 when it is operated in steam electrolysis mode will be described below. First, a voltage is applied to the end plates 2 and 3 of the cell stack 1. Next, a high-temperature mixed gas of water vapor and hydrogen is supplied from the path Pfi. The mixed gas flows into the fuel chamber Sf of each electrochemical unit U through the horizontal holes 7a. Here, water vapor is the gas to be electrolyzed, and hydrogen is a reducing gas for reducing oxidation of the catalyst contained in the fuel electrode 16. Furthermore, when high-temperature air is supplied from the path Pai, the air flows into the air chamber Sa of each electrochemical unit U through horizontal holes (not shown). The high-temperature air is supplied in order to control the temperature of the cell stack 1.

[0049] Water vapor contained in the mixed gas flowing into the fuel chamber Sf passes through the support layer 18a of the fuel electrode 16 and travels to the functional layer 18b. In the functional layer 18b, the water vapor reacts with electrons (electrons supplied from the end plate 3 via the current collector 8) and decomposes into hydrogen and oxide ions. The hydrogen diffuses within the fuel chamber Sf, is discharged through the horizontal hole 7b via a path Pfo, and is collected by a known method. At this time, unreacted water vapor is discharged along with the hydrogen via the path Pfo. Meanwhile, the oxide ions travel through the solid electrolyte layer 12 to the air electrode 14 in the air chamber Sa, where they release electrons at the functional layer of the air electrode 14 and become oxygen. The oxygen diffuses within the air chamber Sa and is discharged through the horizontal hole (not shown) via a path Pao together with the air that has flowed into the air chamber Sa and is collected by a known method. The electrons emitted from the functional layer are collected by the current collecting part 4a of the interconnector 4 via the current collecting layer and circulate from the end plate 2 to the end plate 3 via an external power source. As a result, a current corresponding to the applied voltage (applied current) flows through the cell stack 1.

[0050] Hereinafter, the gas supplied to the fuel chamber Sf from the path Pfi will be referred to as the "first supply gas," and the gas supplied to the air chamber Sa from the path Pai will be referred to as the "second supply gas." In all electrolysis modes (steam electrolysis mode, carbon dioxide electrolysis mode, and co-electrolysis mode), the first supply gas consists of a gas to be electrolyzed and a reducing gas. The reducing gas is hydrogen, and the second supply gas is air. For this reason, a description of the operation when the cell stack 1 is operated in the carbon dioxide electrolysis mode or the co-electrolysis mode will be omitted. Carbon monoxide may also be used as the reducing gas.

[0051] Next, we will explain the operation of the cell stack 1 when it is operated in fuel cell mode. First, the end plates 2 and 3 are connected to an external circuit. Next, when high-temperature hydrogen is supplied through path Pfi, the hydrogen flows into the fuel chamber Sf through the horizontal hole 7a. When high-temperature air is supplied through path Pai, the air flows into the air chamber Sa through a horizontal hole (not shown). The oxygen in the air that flows into the air chamber Sa receives electrons (electrons supplied from the end plate 2 via the current collector 4a) at the air electrode 14 and becomes oxide ions. "Gases other than oxygen in the air" and "unreacted oxygen" diffuse within the air chamber Sa and are discharged through the horizontal hole (not shown) and recovered via path Pao. The oxide ions travel through the solid electrolyte layer 12 to the fuel electrode 16 in the fuel chamber Sf, where they release electrons and combine with hydrogen to form water vapor in the functional layer 18b. The water vapor diffuses within the fuel chamber Sf and, together with unreacted hydrogen, is discharged through path Pfo via the horizontal hole 7b and recovered. The emitted electrons are collected by current collector 8 via support layer 18a and circulate from end plate 3 through an external circuit to end plate 2. Electric power is extracted from the external circuit in a predetermined manner.

[0052] That is, in the fuel cell mode, the first supply gas is hydrogen, and the second supply gas is air. Hereinafter, the compound target gas contained in the first supply gas will be referred to as the "first compound target gas," and the compound target gas contained in the second supply gas will be referred to as the "second compound target gas." In this embodiment, since the first compound target gas is hydrogen, the first supply gas is also the first compound target gas. On the other hand, the second compound target gas is oxygen. Note that the first supply gas may contain gases other than hydrogen (for example, water vapor and / or carbon dioxide).

[0053] The cell stack 1 is operated under predetermined operating conditions for each operating mode. When the operating mode is the electrolysis mode, the operating conditions include the following items. Volumetric flow rate of first supply gas Ve1 Volumetric flow rate of second supply gas Ve2 Cell stack 1 temperature Te Applied current value A Ratio of the volumetric flow rate of the gas to be electrolyzed to the first supply gas R

[0054] The values ​​Ve1, Ve2, Te, A, and R are set in advance and may be different or the same depending on the type of electrolysis mode.

[0055] On the other hand, when the operating mode is the fuel cell mode, the operating conditions include the following items. First supply gas volume flow rate Vf1 Second supply gas volume flow rate Vf2 Cell stack 1 temperature Tf

[0056] The values ​​Vf1, Vf2 and Tf are preset.

[0057] Here, the cell stack 1 has pressure loss due to its internal structure, and the amount of pressure loss varies for each cell stack 1. In addition, the amount of pressure loss in the cell stack 1 also changes depending on the operating conditions of each operating mode.

[0058] Therefore, in this embodiment, "data on the amount of pressure loss of the cell stack 1 for each operating mode when operated under specified operating conditions" is recorded in the QR code 20, and the QR code 20 is printed on the upper surface of the end plate 2 (i.e., in a position visible from the outside). Herein, the "amount of pressure loss of the cell stack 1" includes both the "amount of pressure loss from the end Efi of the path Pfi to the end Efo of the path Pfo" and the "amount of pressure loss from the end Eai of the path Pai to the end Eao of the path Pao." Hereinafter, the former will be referred to as the "first pressure loss amount," and the latter will be referred to as the "second pressure loss amount." The QR code 20 records the amount of pressure loss of the cell stack 1 for each operating mode, linked to the operating conditions. Therefore, the operating conditions and the amount of pressure loss for each operating mode can be easily obtained simply by reading the QR code 20 with a specified QR code reader. Hereinafter, the operating conditions and the amount of pressure loss recorded in the QR code 20 will also be referred to as "pressure loss characteristic information."

[0059] The amount of pressure loss will be explained in more detail. Regardless of the type of operation mode, a portion of the first supply gas leaks to the outside of the cell stack 1 without being discharged from the path Pfo. The leakage amount of the first supply gas depends on the volumetric flow rate Ve1 or Vf1 of the first supply gas. Furthermore, even if a first supply gas having the same volumetric flow rate Ve1 or Vf1 is supplied, the leakage amount differs for each cell stack 1. Similarly, a portion of the second supply gas leaks to the outside of the cell stack 1 without being discharged from the path Pao. The leakage amount of the second supply gas depends on the volumetric flow rate Ve2 or Vf2 of the second supply gas. Furthermore, even if a second supply gas having the same volumetric flow rate Ve2 or Vf2 is supplied, the leakage amount differs for each cell stack 1.

[0060] In addition, when the operating mode is the electrolysis mode, as described above, a portion of the gas to be electrolyzed is discharged unreacted. The "proportion of the volumetric flow rate of the gas to be electrolyzed that is actually used for the reaction out of the supplied gas to be electrolyzed" differs for each cell stack 1. Hereinafter, this proportion will be referred to as the "effective utilization rate of the gas to be electrolyzed."

[0061] On the other hand, when the operating mode is the fuel cell mode, as described above, a portion of the first compound target gas and a portion of the second compound target gas are discharged unreacted. The "proportion of the volumetric flow rate of the first or second compound target gas that is actually used in the reaction out of the supplied first or second compound target gas" differs for each cell stack 1. Hereinafter, this proportion will be referred to as the "effective utilization rate of the first or second compound target gas."

[0062] As described above, when the operation mode is the electrolysis mode, the first pressure loss amount depends on the "leakage amount of the first supply gas" and the "effective utilization rate of the gas to be electrolyzed," and therefore these factors are reflected in the first pressure loss amount recorded in the QR code 20. In addition, the second pressure loss amount also depends on the "leakage amount of the second supply gas," and therefore this factor is reflected in the second pressure loss amount recorded in the QR code 20.

[0063] On the other hand, when the operating mode is the fuel cell mode, the first pressure loss amount depends on the "leakage amount of the first supply gas" and the "effective utilization rate of the first compound target gas." In addition, the first pressure loss amount also depends on the amount of power generation. Therefore, the first pressure loss amount recorded in the QR code 20 is a value that reflects these factors. In addition, the second pressure loss amount also depends on the "leakage amount of the second supply gas" and the "effective utilization rate of the second compound target gas." In addition, the second pressure loss amount also depends on the amount of power generation. Therefore, the second pressure loss amount recorded in the QR code 20 is a value that reflects these factors.

[0064] The values ​​of these factors may be recorded in the QR code 20. This is because it makes it possible to check the variation in factors for each cell stack 1.

[0065] Conventionally, the first and second pressure loss amounts in each operation mode have been measured when the cell stack 1 manufacturer inspects the product. The QR code 20 can be created based on the data obtained at the time of this measurement. By printing the QR code 20, which records the data obtained at the time of inspection, on the cell stack 1 (i.e., the actual device itself), the delivery destination of the cell stack 1 can obtain the information necessary for manufacturing the cell stack system without having to measure the pressure loss amounts again.

[0066] Next, the configuration of the cell stack system 100 will be described with reference to Figure 4. The cell stack system 100 includes six cell stacks 1A to 1F. The cell stacks 1A to 1F all have substantially the same configuration as the cell stack 1. However, the first and second pressure losses vary from cell stack to cell stack. When the system 100 is operated in electrolysis mode, the cell stacks 1A to 1F are connected in series to an external power supply (not shown). On the other hand, when the system 100 is operated in fuel cell mode, the cell stacks 1A to 1F are connected in series to an external circuit (not shown).

[0067] In the system 100, the fuel chambers Sf of each of the cell stacks 1A to 1F are connected in parallel to a supply pipe 21 and a discharge pipe 31. Specifically, the supply pipe 21 branches into a supply pipe 21A and a supply pipe 21B at a branch b1. The supply pipe 21A is connected to an end Efi (not shown) of a path Pfi of the cell stacks 1A to 1C by branch pipes 21a to 21c, respectively. The supply pipe 21B is connected to an end Efi (not shown) of the cell stacks 1D to 1F by branch pipes 21d to 21f, respectively. Furthermore, the discharge pipe 31 branches into a discharge pipe 31A and a discharge pipe 31B at a branch b3. The discharge pipe 31A is connected to an end Efo (not shown) of a path Pfo of the cell stacks 1A to 1C by branch pipes 31a to 31c, respectively. The discharge pipe 31B and the ends Efo (not shown) of the cell stacks 1D to 1F are connected by branch pipes 31d to 31f, respectively.

[0068] Similarly, in the system 100, the air chamber Sa of each of the cell stacks 1A to 1F is connected in parallel to the supply pipe 22 and the discharge pipe 32. Specifically, the supply pipe 22 branches into a supply pipe 22A and a supply pipe 22B at branch b1. The supply pipe 22A and an end Eai (not shown) of the path Pai of the cell stacks 1A to 1C are connected by branch pipes 22a to 22c, respectively. The supply pipe 22B and an end Eai (not shown) of the cell stacks 1D to 1F are connected by branch pipes 22d to 22f, respectively. Furthermore, the discharge pipe 32 branches into a discharge pipe 32A and a discharge pipe 32B at branch b3. The discharge pipe 32A and an end Eao (not shown) of the path Pfo of the cell stacks 1A to 1C are connected by branch pipes 32a to 32c, respectively. The discharge pipe 32B and the ends Eao (not shown) of the cell stacks 1D to 1F are connected by branch pipes 32d to 32f, respectively.

[0069] The supply gas introduced into the supply pipe 21 is distributed and supplied to the path Pfi of the cell stacks 1A to 1F from the supply pipes 21A and 21B via the branch pipes 21a to 21f. The supply gas distributed and supplied to the path Pfi flows into the fuel chamber Sf as the first supply gas. The exhaust gas discharged from the path Pfo of the cell stacks 1A to 1F flows from the branch pipes 31a to 31f via the exhaust pipes 31A and 31B to join the exhaust pipe 31 and is then recovered. Similarly, the supply gas introduced into the supply pipe 22 is distributed and supplied to the path Pai of the cell stacks 1A to 1F from the supply pipes 22A and 22B via the branch pipes 22a to 22f. The supply gas distributed and supplied to the path Pai flows into the air chamber Sa as the second supply gas. The exhaust gas discharged from the path Pao of the cell stacks 1A to 1F passes through the branch pipes 32a to 32f and the exhaust pipes 32A and 32B to join the exhaust pipe 32, and is then recovered.

[0070] The system 100 can be manufactured by the following procedure. That is, first, the cell stacks 1A to 1F are prepared. Next, the QR codes 20 printed on each of the cell stacks 1A to 1F are read using a QR code reader to obtain its pressure loss characteristic information (i.e., operating conditions and pressure loss amount). Next, the relative positional relationship of the cell stacks 1A to 1F is determined based on the obtained pressure loss characteristic information (more specifically, the pressure loss amount). At this time, if necessary, pressure loss adjustment components (typically, orifices) may be attached to any of the branch pipes 31a to 31f and 32a to 32f to adjust the pressure loss between the upstream and downstream sides of each of the cell stacks 1A to 1F.

[0071] Specifically, for example, when the system 100 is scheduled to operate in fuel cell mode, the temperature in the central region of the system 100 may become higher than the set temperature Tf due to an exothermic reaction. As the temperature increases, the viscosity of the gas increases, which tends to increase the amount of pressure loss. For this reason, the relative positional relationship may be determined so that the cell stacks with relatively small amounts of pressure loss among the cell stacks 1A to 1F are positioned in the central region (in the example of FIG. 4, the center of the upper row and the center of the lower row). In this way, by determining the relative positional relationship by taking advantage of the individual differences in the amount of pressure loss among the cell stacks 1A to 1F, the pressure loss adjusting components can be used efficiently.

[0072] Alternatively, pressure loss adjusting components may be installed so that the amount of pressure loss between the upstream and downstream sides of all cell stacks 1A to 1F is equal. This allows the supply gas to be equally distributed and supplied from supply pipes 21 and 22 to each of cell stacks 1A to 1F (in other words, the volumetric flow rate Ve1 or Vf1 of the first supply gas supplied to each cell stack can be made equal, and the volumetric flow rate Ve2 or Vf2 of the second supply gas can be made equal), resulting in efficient operation of system 100.

[0073] Next, the hydrogen production device 40 and the hot module 41 will be described with reference to Fig. 5. When the cell stack system 100 in Fig. 4 is operated in electrolysis mode, the system 100 becomes a component of a gas production device. Specifically, when the electrolysis mode is the steam electrolysis mode, the carbon dioxide electrolysis mode, or the co-electrolysis mode, the system 100 becomes a component of a hydrogen production device 40, a carbon monoxide production device, and a synthesis gas production device, respectively. Below, the gas production device will be described using the hydrogen production device 40 as an example.

[0074] 5 is a block diagram of the hydrogen production device 40. The hydrogen production device 40 is a device that produces hydrogen from water, and includes a hot module 41 and a condenser 46.

[0075] The system 100 is a component of the hot module 41. That is, the hot module 41 includes six cell stacks 1A to 1F in the system 100, a vaporizer 42, a heat exchanger 43, a heater 44, and a thermal insulator 45. The vaporizer 42 generates steam to be supplied to the system 100. The heat exchanger 43 exchanges heat between the supply gas to be supplied to the system 100 and the product gas generated by the system 100. The heater 44 heats the system 100. The system 100, the vaporizer 42, the heat exchanger 43, and the heater 44 are disposed inside the thermal insulator 45. This suppresses heat radiation from the systems 100 and 42 to 44.

[0076] The vaporizer 42 includes a heat exchanger (not shown). This heat exchanger is capable of exchanging heat with high-temperature exhaust gas containing oxygen generated by each system 100. The vaporizer 42 heats water with heat from the heat exchanger to generate water vapor. This water vapor contains hydrogen. The water vapor (strictly speaking, water vapor containing hydrogen) generated by the vaporizer 42 exchanges heat with hydrogen and oxygen generated by the system 100 in the heat exchanger 43. The water vapor is then heated by the heater 44 to the operating temperature Te of the system 100 and supplied to the fuel chamber Sf through the paths Pfi of each of the cell stacks 1A to 1F. Meanwhile, air exchanges heat with the hydrogen and oxygen generated by the system 100 in the heat exchanger 43. The air is then heated by the heater 44 to the operating temperature Te and supplied to the air chamber Sa through the paths Pai of each of the cell stacks 1A to 1F.

[0077] Heat-resistant fibers such as ceramic wool, refractory ceramic fiber (RCF), and biosoluble fiber (AES), and / or a heat-resistant container made of these heat-resistant fibers, may be used for the heat insulating material 45. The heat-resistant fibers are arranged so as to fill gaps between the cell stacks 1A to 1F, the vaporizer 42, the heat exchanger 43, and the heater 44.

[0078] The condenser 46 is a device for cooling hydrogen containing unreacted water vapor. The water liquefied by the condenser 46 is supplied to the vaporizer 42 again as raw water.

[0079] The operation of the carbon monoxide production unit and the synthesis gas production unit is the same as that of the hydrogen production unit except for the type of gas, and therefore a description of these operations will be omitted.

[0080] As described above, the cell stack 1 according to this embodiment has pressure loss characteristic information printed in a position that is visible from the outside. Therefore, workers at the destination of delivery of the cell stack 1 can easily obtain the first and second pressure loss amounts simply by referring to the pressure loss characteristic information printed on the cell stack 1. In other words, the work of measuring the pressure loss amounts is no longer necessary, and there is no need to operate the cell stack system 100 for the purpose of measurement. Therefore, the time and effort involved in obtaining the pressure loss amounts can be significantly reduced, and as a result, the effort involved in adjusting the pressure loss between the upstream and downstream sides of the cell stack 1 can be significantly reduced.

[0081] In particular, when manufacturing the cell stack system 100, the pressure loss amount can be obtained before assembling the cell stacks 1A to 1F, and the relative positional relationship of the cell stacks 1A to 1F can be determined based on the six obtained pressure loss amounts. This allows for efficient use of pressure loss adjustment parts, further reducing the effort required for adjusting the pressure loss.

[0082] In addition, because the pressure loss characteristic information includes the amount of pressure loss for each operating mode, the amount of pressure loss for each operating mode can be appropriately obtained even in the case of reversible operation.Furthermore, because the pressure loss characteristic information includes the amount of pressure loss for four operating modes, the versatility of the cell stack can be maintained.

[0083] In this embodiment, the first and second pressure loss amounts are the pressure loss amounts when the system is operated under predetermined operating conditions in each operating mode, which increases the accuracy of the first and second pressure loss amounts and, as a result, ensures the reliability of the pressure loss characteristic information.

[0084] Furthermore, in this embodiment, pressure loss characteristic information is recorded in a QR code 20 printed on the upper surface of the end plate 2 of the cell stack 1. Therefore, by reading the pressure loss characteristic information once using a QR code reader, the amount of pressure loss can be obtained (confirmed) even at a location away from the assembly site of the cell stack 1, improving convenience.

[0085] In addition, by using a QR code as a format for recording pressure drop characteristic information, it can be printed compactly on the cell stack 1.

[0086] Furthermore, the manufacturing method for the cell stack system 100 according to this embodiment makes it possible to determine the relative positional relationship by taking advantage of the individual differences in the amount of pressure loss among the cell stacks 1A to 1F. This allows for efficient use of pressure loss adjustment components, further reducing the effort required to adjust the pressure loss.

[0087] The above describes the cell stack, cell stack system manufacturing method, hot module, and gas production apparatus according to the embodiments, but the present invention is not limited to the above embodiments, and various modifications are possible as long as they do not deviate from the purpose of the present invention.

[0088] For example, the QR code 20 may be attached as a sticker instead of being printed on the cell stack 1. Furthermore, the form in which the pressure loss characteristic information is posted is not limited to the QR code 20.

[0089] Furthermore, when the operating mode is the electrolysis mode, the first pressure loss amount does not necessarily have to be a value that reflects all of the "applied current value A," "volume flow rate ratio R of the gas to be electrolyzed to the first supply gas," "effective utilization rate of the gas to be electrolyzed," and "leakage amount of the first supply gas," but may be a value that reflects at least one of these. Furthermore, the second pressure loss amount does not necessarily have to be a value that reflects both the "applied current value A" and the "leakage amount of the second supply gas," but may be a value that reflects at least one of these. Similarly, when the operating mode is the fuel cell mode, the first pressure loss amount does not necessarily have to be a value that reflects all of the "effective utilization rate of the first compound gas," "leakage amount of the first supply gas," and "power generation amount in a predetermined period of time," but may be a value that reflects at least one of these. Furthermore, the second pressure loss amount does not necessarily have to be a value that reflects all of the "effective utilization rate of the second compound gas," "leakage amount of the second supply gas," and "power generation amount in a specified time," but may be a value that reflects at least one of these.

[0090] Furthermore, the operation modes do not have to include all of the steam electrolysis mode, carbon dioxide electrolysis mode, co-electrolysis mode, and fuel cell mode, but may include at least one of these operation modes.

[0091] Furthermore, the present invention may include the following aspects. [1] A cell stack including a plurality of solid oxide electrochemical unit cells, each of which includes a solid electrolyte layer, an air electrode stacked on a front surface side of the solid electrolyte layer, and a fuel electrode stacked on a back surface side of the solid electrolyte layer, a first supply path for supplying gas to a fuel chamber, which is a space on the fuel electrode side in the cell stack; a first discharge passage for discharging gas from the fuel chamber; a second supply path for supplying gas to an air chamber, which is a space on the air electrode side in the cell stack; a second exhaust passage for exhausting gas from the air chamber; Equipped with pressure loss characteristic information including, for each of a plurality of operation modes distinguished according to the type of gas produced, at least one of a first pressure loss amount, which is the amount of pressure loss from the end of the first supply channel to the end of the first discharge channel, and a second pressure loss amount, which is the amount of pressure loss from the end of the second supply channel to the end of the second discharge channel, when the cell stack is operated in each of the plurality of operation modes distinguished according to the type of gas produced, is displayed in a position visible from the outside; Cell stack. [2] [1] The cell stack according to [1], the first pressure loss amount includes a pressure loss amount that depends on a volume flow rate of the first supply gas supplied from the first supply path and a temperature of the cell stack, the second pressure loss amount includes a pressure loss amount that depends on the volume flow rate of the second supply gas supplied from the second supply channel and the temperature; Cell stack. [3] The cell stack according to [1] or [2], In an operation mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell, the first pressure loss amount includes a pressure loss amount that depends on at least one of an applied current, a volumetric flow rate ratio of a gas to be electrolyzed that is contained in a first supply gas supplied from the first supply path to the first supply gas, an effective utilization rate of the gas to be electrolyzed, and a leakage amount of the first supply gas; the second pressure loss amount includes a pressure loss amount that depends on at least one of the applied current and a leakage amount of the second supply gas supplied from the second supply path, In an operation mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell, the first pressure loss amount includes a pressure loss amount that depends on at least one of an amount of power generation in a predetermined time, an effective utilization rate of a first compound target gas that is contained in the first supply gas and is a target for compounding, and an amount of leakage of the first supply gas, The second pressure loss amount includes a pressure loss amount that depends on at least one of the amount of power generation, the effective utilization rate of a second compound target gas that is contained in the second supply gas and is a target for compounding, and the amount of leakage of the second supply gas. Cell stack. [4] A cell stack according to any one of [1] to [3], The operation mode is a first mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate hydrogen; a second mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate carbon monoxide; a third mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to produce a synthesis gas comprising hydrogen and carbon monoxide; a fourth mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell for generating water vapor; including at least one mode of Cell stack. [5] A cell stack according to any one of [1] to [4], The pressure loss characteristic information is published in a form that can be read using an external device. Cell stack. [6] [5] A cell stack according to [5], The form is a two-dimensional barcode. Cell stack. [7] A method for manufacturing a cell stack system including a plurality of cell stacks according to any one of [1] to [6], providing the plurality of cell stacks; acquiring the pressure drop characteristic information listed on each of the plurality of cell stacks; determining a relative positional relationship between the plurality of cell stacks based on the acquired pressure loss characteristic information; Including, A method for manufacturing a cell stack system. [8] One or more cell stacks according to any one of [1] to [6]; a heat exchanger that exchanges heat with the gas supplied to the cell stack; a heater for heating the cell stack; a heat insulating material in which the cell stack, the heat exchanger, and the heater are disposed; Equipped with Hot module. [9] [8] The hot module is used in an operation mode in which each of the plurality of electrochemical single cells is used as an electrolysis single cell. Gas production equipment. [Explanation of symbols]

[0092] 1: cell stack, 2: end plate, 3: end plate, 4: interconnector, 5: separator, 6: air electrode frame, 7: anode frame, 8: current collector, 9: (lowest) interconnector, 10: solid oxide electrolysis unit cell, 12: solid electrolyte layer, 14: air electrode, 16: anode, 18a: support layer, 18b: functional layer, 21: anode supply pipe, 22: cathode supply pipe, 31: anode discharge pipe, 32: cathode discharge pipe, 40: hydrogen production device, 41: hot module, 42: vaporizer, 43: heat exchanger, 44: heater, 45: heat insulator, 46: condenser

Claims

1. A cell stack including a plurality of solid oxide electrochemical unit cells, each of which includes a solid electrolyte layer, an air electrode stacked on a front surface side of the solid electrolyte layer, and a fuel electrode stacked on a back surface side of the solid electrolyte layer, a first supply path for supplying gas to a fuel chamber, which is a space on the fuel electrode side in the cell stack; a first exhaust passage for exhausting gas from the fuel chamber; a second supply path for supplying gas to an air chamber, which is a space on the air electrode side in the cell stack; a second exhaust passage for exhausting gas from the air chamber; Equipped with pressure loss characteristic information including, for each of a plurality of operation modes distinguished according to the type of gas produced, at least one of a first pressure loss amount, which is the amount of pressure loss from an end of the first supply channel to an end of the first discharge channel, and a second pressure loss amount, which is the amount of pressure loss from the end of the second supply channel to an end of the second discharge channel, when the cell stack is operated in each of the plurality of operation modes distinguished according to the type of gas produced, is displayed in a position visible from the outside; Cell stack.

2. The cell stack according to claim 1, the first pressure loss amount includes a pressure loss amount that depends on a volume flow rate of the first supply gas supplied from the first supply path and a temperature of the cell stack, the second pressure loss amount includes a pressure loss amount that depends on the volume flow rate and the temperature of the second supply gas supplied from the second supply path. Cell stack.

3. The cell stack according to claim 1 or 2, In an operation mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell, the first pressure loss amount includes a pressure loss amount that depends on at least one of an applied current, a volumetric flow rate ratio of a gas to be electrolyzed that is contained in a first supply gas supplied from the first supply path to the first supply gas, an effective utilization rate of the gas to be electrolyzed, and a leakage amount of the first supply gas; the second pressure loss amount includes a pressure loss amount that depends on at least one of the applied current and a leakage amount of the second supply gas supplied from the second supply path, In an operation mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell, the first pressure loss amount includes a pressure loss amount that depends on at least one of an amount of power generation in a predetermined time, an effective utilization rate of a first compound target gas that is contained in the first supply gas and is a target for compounding, and an amount of leakage of the first supply gas, the second pressure loss amount includes a pressure loss amount that depends on at least one of the amount of power generation, an effective utilization rate of a second compound target gas that is contained in the second supply gas and is a target for compounding, and a leakage amount of the second supply gas. Cell stack.

4. The cell stack according to claim 1, The operation mode is a first mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate hydrogen; a second mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to generate carbon monoxide; a third mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell to produce a synthesis gas comprising hydrogen and carbon monoxide; a fourth mode in which each of the plurality of electrochemical unit cells is used as a fuel cell unit cell for generating water vapor; and at least one mode of Cell stack.

5. The cell stack according to claim 1, claim 2 or claim 4, The pressure loss characteristic information is published in a form that can be read using an external device. Cell stack.

6. The cell stack according to claim 5, The form is a two-dimensional barcode. Cell stack.

7. A method for manufacturing a cell stack system including a plurality of cell stacks according to claim 1, comprising: providing the plurality of cell stacks; acquiring the pressure drop characteristic information listed on each of the plurality of cell stacks; determining a relative positional relationship between the plurality of cell stacks based on the acquired pressure loss characteristic information; Including, A method for manufacturing a cell stack system.

8. One or more cell stacks according to claim 1; a heat exchanger that exchanges heat with the gas supplied to the cell stack; a heater for heating the cell stack; a heat insulating material in which the cell stack, the heat exchanger, and the heater are disposed; Equipped with Hot module.

9. The hot module according to claim 8 is used in an operation mode in which each of the plurality of electrochemical unit cells is used as an electrolysis unit cell. Gas production equipment.

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