Electrochemical cell device, module, and module accommodating device

Abstract

This electrochemical cell device comprises a cell stack and a connection member. The cell stack includes a first cell. The cell stack has a high-potential part and a low-potential part having a potential lower than that of the high-potential part. The connection member is electrically connected to either the high-potential part or the low-potential part of the cell stack. The connection member includes: a first lead-out part located in a high-temperature part of the cell stack; and a second lead-out part located in a low-temperature part of the cell stack, the low-temperature part having a temperature lower than that of the high-temperature part.

Description

Electrochemical cell device, module, and module housing device

[0001] The present disclosure relates to electrochemical cell devices, modules and module housing devices.

[0002] In recent years, various fuel cell stack devices have been proposed as next-generation energy sources, including fuel cells, which are a type of cell that can generate electricity using a fuel gas such as a hydrogen-containing gas and an oxygen-containing gas such as air.

[0003] JP 2021-180164 A JP 2015-220022 A

[0004] An electrochemical cell device according to one aspect of the embodiment includes a cell stack and a connecting member. The cell stack includes a first cell. The cell stack has a high potential portion and a low potential portion having a lower potential than the high potential portion. The connecting member is electrically connected to the high potential portion or the low potential portion of the cell stack. The connecting member has a first lead portion located in a high temperature portion of the cell stack and a second lead portion located in a low temperature portion of the cell stack having a lower temperature than the high temperature portion.

[0005] The module of the present disclosure includes the electrochemical cell device described above and a container that houses the electrochemical cell device.

[0006] The module housing device of the present disclosure includes the module described above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0007] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. FIG. 1B is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the interconnector side. FIG. 2A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. FIG. 2B is a top view showing an example of an electrochemical cell device according to the first embodiment. FIG. 2C is a cross-sectional view taken along line X-X shown in FIG. 2A. FIG. 3 is a cross-sectional view showing an example of a connecting member included in the electrochemical cell according to the first embodiment. FIG. 4 is a plan view of the connecting member shown in FIG. 3. FIG. 5 is a cross-sectional view showing another example of a connecting member included in the electrochemical cell according to the first embodiment. FIG. 6 is a plan view of the connecting member shown in FIG. 5. FIG. 7 is a plan view showing another example of a connecting member included in the electrochemical cell according to the first embodiment. FIG. 8 is an external perspective view showing an example of a module according to an embodiment. FIG. 9 is an exploded perspective view schematically showing an example of a module housing device according to an embodiment. FIG. 10 is a perspective view showing an example of an electrochemical cell according to a second embodiment. Fig. 11 is a perspective view showing an example of an electrochemical cell device according to a second embodiment. Fig. 12 is a perspective view showing an example of an electrochemical cell according to a third embodiment. Fig. 13 is a perspective view showing an example of an electrochemical cell device according to the third embodiment.

[0008] In the above-described fuel cell stack device, for example, there are cases where variations in temperature occur during power generation, which may reduce durability.

[0009] Therefore, there is a need to provide highly durable electrochemical cell devices, modules, and module housing devices.

[0010] Hereinafter, embodiments of an electrochemical cell device, a module, and a module housing device disclosed in the present application will be described in detail with reference to the accompanying drawings. However, the disclosure is not limited to the embodiments described below.

[0011] It should also be noted that the drawings are schematic and that the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may contain parts whose dimensional relationships and ratios differ from one another.

[0012] 1A to 1C, electrochemical cells constituting an electrochemical cell device according to a first embodiment will be described using an example of a solid oxide fuel cell. The electrochemical cell device may include a cell stack having a plurality of electrochemical cells. An electrochemical cell device having a plurality of electrochemical cells will be simply referred to as a cell stack device.

[0013] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. FIG. 1B is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the interconnector side. Note that FIGS. 1A to 1C show enlarged views of parts of each component of the electrochemical cell. Hereinafter, the electrochemical cell may also be simply referred to as a cell.

[0014] 1A to 1C, the cell 1 is a hollow, flat, elongated plate. As shown in Fig. 1B, the shape of the entire cell 1 as viewed from the side may be, for example, a rectangle with a side length of 5 cm to 50 cm in the length direction L and a length of 1 cm to 10 cm in the width direction W perpendicular to the length direction L. The thickness of the entire cell 1 in the thickness direction T may be, for example, 1 mm to 5 mm.

[0015] 1A, the cell 1 includes a conductive support substrate 2, an element section 3, and an interconnector 4. The support substrate 2 is columnar, having a pair of opposing flat surfaces n1 and n2, and a pair of arc-shaped side surfaces m connecting the surfaces n1 and n2.

[0016] The element section 3 is located on the surface n1 of the support substrate 2. The element section 3 has an anode 5, a solid electrolyte layer 6, and an air electrode 8. In the example shown in FIG. 1A , the interconnector 4 is located on the surface n2 of the cell 1. The cell 1 may also include an intermediate layer 7 between the solid electrolyte layer 6 and the air electrode 8.

[0017] 1B, the air electrode 8 does not extend to the lower end of the cell 1. At the lower end of the cell 1, only the solid electrolyte layer 6 is exposed on the surface of face n1. As shown in FIG. 1C, the interconnector 4 may extend to the lower end of the cell 1. At the lower end of the cell 1, the interconnector 4 and the solid electrolyte layer 6 are exposed on the surface. As shown in FIG. 1A, the solid electrolyte layer 6 is exposed on the surface of a pair of arc-shaped side faces m of the cell 1. The interconnector 4 does not have to extend to the lower end of the cell 1.

[0018] Each of the components constituting the cell 1 will be described below.

[0019] The support substrate 2 has gas flow channels 2a therein through which gas flows. The example of the support substrate 2 shown in FIG. 1A has six gas flow channels 2a. The support substrate 2 has gas permeability, and allows the gas flowing in the gas flow channels 2a to pass through to the anode 5. The support substrate 2 may be conductive. The conductive support substrate 2 collects electricity generated in the element portion to the interconnector 4.

[0020] The material of the support substrate 2 includes, for example, an iron-group metal component and an inorganic oxide. The iron-group metal component may be, for example, Ni (nickel) and / or NiO. The inorganic oxide may be, for example, a specific rare earth element oxide. The rare earth element oxide may include, for example, one or more rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb.

[0021] A generally known material can be used for the fuel electrode 5. The fuel electrode 5 is made of a porous conductive ceramic, such as calcium oxide, magnesium oxide, or ZrO in which a rare earth element oxide is solid-solved. ２and Ni and / or NiO may be used. The rare earth element oxide may contain, for example, a plurality of rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. Calcium oxide, magnesium oxide, or ZrO in which a rare earth element oxide is solid-solved may be used. ２ The stabilized zirconia may include partially stabilized zirconia.

[0022] The solid electrolyte layer 6 is an electrolyte and transfers ions between the fuel electrode 5 and the air electrode 8. At the same time, the solid electrolyte layer 6 has gas barrier properties and makes it difficult for leakage of fuel gas and oxygen-containing gas to occur.

[0023] The material of the solid electrolyte layer 6 is, for example, ZrO in which 3 mol % to 15 mol % of rare earth element oxide is dissolved. ２ The rare earth element oxide may contain, for example, one or more rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. The solid electrolyte layer 6 may be, for example, ZrO in which Yb, Sc, or Gd is solid-solved. ２ and CeO in which La, Nd or Yb is solid-solved. ２ and BaZrO in which Sc or Yb is solid-solved. ３ and BaCeO in which Sc or Yb is solid-solved. ３ may include:

[0024] The air electrode 8 is gas permeable. The open porosity of the air electrode 8 may be, for example, in the range of 20% to 50%, particularly 30% to 50%. The open porosity of the air electrode 8 may also be referred to as the porosity of the air electrode 8.

[0025] There are no particular limitations on the material of the air electrode 8 as long as it is a material that is generally used for air electrodes. ３ Conductive ceramics such as perovskite oxides may also be used.

[0026] The material of the air electrode 8 may be, for example, a composite oxide in which Sr (strontium) and La (lanthanum) coexist at the A site. Examples of such composite oxides include La ｘ Sr１－ｘ Co ｙ Fe １－ｙ O ３ , La ｘ Sr １－ｘ MnO ３ , La ｘ Sr １－ｘ FeO ３ , La ｘ Sr １－ｘ CoO ３ Here, x is 0<x<1, and y is 0<y<1.

[0027] Furthermore, when the element section 3 has the intermediate layer 7, the intermediate layer 7 functions as a diffusion suppression layer. When Sr (strontium) contained in the air electrode 8 diffuses into the solid electrolyte layer 6, the solid electrolyte layer 6 is coated with SrZrO ３ The intermediate layer 7 is formed as a resistive layer of SrZrO by making it difficult for Sr to diffuse. ３ This makes it difficult for

[0028] The material of the intermediate layer 7 is not particularly limited as long as it is generally used as an element diffusion suppression layer between the air electrode 8 and the solid electrolyte layer 6. The material of the intermediate layer 7 is, for example, cerium oxide (CeO) in which rare earth elements other than Ce (cerium) are dissolved. ２ ) may be included. Examples of such rare earth elements include Gd (gadolinium) and Sm (samarium).

[0029] Furthermore, the interconnector 4 is dense and makes it difficult for leakage of the fuel gas flowing through the gas flow passage 2a located inside the support substrate 2 and the oxygen-containing gas flowing outside the support substrate 2 to occur. The interconnector 4 may have a relative density of 93% or more, particularly 95% or more.

[0030] The material of the interconnector 4 is a lanthanum chromite-based perovskite oxide (LaCrO ３ -based oxides), lanthanum strontium titanium-based perovskite-type oxides (LaSrTiO ３ These materials are electrically conductive and are not easily reduced or oxidized even when in contact with fuel gases such as hydrogen-containing gases and oxygen-containing gases such as air.

[0031] <Configuration of Electrochemical Cell Device> Next, an electrochemical cell device according to this embodiment using the above-described cell 1 will be described with reference to Figs. 2A to 2C. Fig. 2A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. Fig. 2B is a top view showing an example of an electrochemical cell device according to the first embodiment. Fig. 2C is a cross-sectional view taken along line XX shown in Fig. 2A.

[0032] As shown in FIG. 2A, the cell stack device 10 includes a cell stack 11 having a plurality of cells 1 arranged (stacked) in the thickness direction T of the cells 1 (see FIG. 1A), and a fixing member 12.

[0033] The fixing member 12 has a fixing material 13 and a support member 14. The support member 14 supports the cell 1. The fixing material 13 fixes the cell 1 to the support member 14. The support member 14 also has a support 15 and a gas tank 16. The support 15 and the gas tank 16, which are the support member 14, are made of metal and are electrically conductive.

[0034] 2C, the support body 15 has insertion holes 15a into which the lower ends of the plurality of cells 1 are inserted. The lower ends of the plurality of cells 1 and the inner wall of the insertion holes 15a are joined with fixing material 13.

[0035] The gas tank 16 has an opening for supplying a reaction gas to the cells 1 through the insertion holes 15a, and a recessed groove 16a located around the opening. The outer peripheral edge of the support 15 is joined to the gas tank 16 by a bonding material 21 filled in the recessed groove 16a of the gas tank 16.

[0036] In the example shown in Fig. 2A, fuel gas is stored in an internal space 22 (see Fig. 2B) formed by a support body 15, which is the support member 14, and a gas tank 16. A gas circulation pipe 20 is connected to the gas tank 16. The fuel gas is supplied to the gas tank 16 through this gas circulation pipe 20, and is supplied from the gas tank 16 to a gas flow path 2a (see Fig. 1A) inside the cell 1. The fuel gas supplied to the gas tank 16 is generated in a reformer 102 (see Fig. 4), which will be described later.

[0037] The hydrogen-rich fuel gas can be produced by steam reforming the raw fuel, etc. When the fuel gas is produced by steam reforming, the fuel gas contains water vapor.

[0038] The example shown in Fig. 2A includes two rows of cell stacks 11, two supports 15, and a gas tank 16. Each of the two rows of cell stacks 11 has a plurality of cells 1. Each cell stack 11 is fixed to a corresponding support 15. The gas tank 16 has two through-holes on its top surface. A support 15 is disposed in each through-hole. An internal space 22 is formed by the one gas tank 16 and the two supports 15.

[0039] The shape of the insertion hole 15a may be, for example, an oval shape when viewed from above. For example, the length of the insertion hole 15a in the arrangement direction of the cells 1, i.e., the thickness direction T, may be greater than the distance between the two end current collecting members 17 located at both ends of the cell stack 11. For example, the width of the insertion hole 15a may be greater than the length of the cell 1 in the width direction W (see FIG. 1A ).

[0040] 2C, a fixing material 13 is filled and solidified at the joint between the inner wall of the insertion hole 15a and the lower end of the cell 1. This bonds and fixes the inner wall of the insertion hole 15a to the lower end of each of the multiple cells 1, and also bonds and fixes the lower ends of the cells 1 to each other. The gas flow path 2a of each cell 1 communicates with the internal space 22 of the support member 14 at its lower end.

[0041] A material with low conductivity, such as glass, can be used for the fixing material 13 and the bonding material 21. Specific materials for the fixing material 13 and the bonding material 21 include amorphous glass, and in particular, crystallized glass.

[0042] Examples of the crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO system, La ２ O ３ -B ２ O３ -ZnO-based, SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２ - MgO-based materials may also be used.

[0043] 2C , a conductive member 18 is interposed between adjacent cells 1 among the plurality of cells 1. The conductive member 18 electrically connects the anode 5 of one adjacent cell 1 to the cathode 8 of the other cell 1 in series. More specifically, the conductive member 18 connects the interconnector 4 electrically connected to the anode 5 of one adjacent cell 1 to the cathode 8 of the other cell 1.

[0044] 2C, an end current collecting member 17 is electrically connected to the cell 1 positioned outermost in the arrangement direction of the multiple cells 1. The end current collecting member 17 is connected to a connecting member 19 that protrudes outside the cell stack 11. The connecting member 19 collects electricity generated by the cells 1 and extracts it to the outside. Note that the end current collecting member 17 is not shown in FIG. 2A.

[0045] 2B, the cell stack device 10 has two cell stacks 11A and 11B connected in series to function as a single battery. The connection member 19 of the cell stack device 10 includes connection members 19A to 19E. The end current collecting member 17 includes members 17A, 17B, 17D, and 17E.

[0046] The connecting member 19A is a positive electrode when the power generated by the cell stack 11 is output to the outside, and is a positive terminal electrically connected to the member 17A, which is the end current collecting member 17 on the positive side of the cell stack 11A. The connecting member 19B is a negative electrode when the power generated by the cell stack 11 is output to the outside, and is a negative terminal electrically connected to the member 17B, which is the end current collecting member 17 on the negative side of the cell stack 11A.

[0047] The connecting member 19D is a positive electrode when the power generated by the cell stack 11 is output to the outside, and is a positive terminal electrically connected to the member 17D, which is the end current collecting member 17 on the positive electrode side in the cell stack 11B. The connecting member 19E is a negative electrode when the power generated by the cell stack 11 is output to the outside, and is a negative terminal electrically connected to the member 17E, which is the end current collecting member 17 on the negative electrode side in the cell stack 11B.

[0048] The connection member 19C is a connection terminal that electrically connects the connection member 19B, which is the negative electrode terminal of the cell stack 11A, and the connection member 19D, which is the positive electrode terminal of the cell stack 11B.

[0049] The connection members 19A to 19E may contain chromium or iron. The connection member 19A is, for example, stainless steel. The connection member 19A may contain, for example, a metal oxide.

[0050] The connection members 19A to 19E may have a coating covering the surface. Such a coating may have oxidation resistance. The coating may also be a conductive coating. The coating may be located on the entire surface of the connection members 19A to 19E, or may be located only on a portion of the surface. The coating may be located only on the surface facing a terminal or conductor electrically connected to the connection members 19A to 19E.

[0051] <Details of the Connecting Members> Next, the connecting members 19A to 19E of the electrochemical cell device according to this embodiment will be further described in detail with reference to FIGS. 2C to 4. FIG.

[0052] Fig. 3 is a cross-sectional view showing an example of a connecting member included in the electrochemical cell according to the first embodiment. For ease of understanding, Fig. 3 shows a three-dimensional Cartesian coordinate system including a Z-axis with the positive direction being the vertical upward direction. This Cartesian coordinate system may also be shown in other drawings used in the following description.

[0053] If the cell stack device 10 has only one each of the connection members 19A to 19E, the connection members 19 may be prone to abnormal heat generation due to current concentration, and the durability of the cell stack device 10 may be prone to decrease.

[0054] Therefore, in this embodiment, the connection member electrically connected to the high potential portion or low potential portion of the cell stack 11 has a first pull-out portion located in the high temperature portion of the cell stack 11 and a second pull-out portion located in the low temperature portion of the cell stack 11 which is at a lower temperature than the high temperature portion.

[0055] 3, the connection member 19A connected to the member 17A has a first lead portion 19A1 and a second lead portion 19A2, and the connection member 19E connected to the member 17E has a first lead portion 19E1 and a second lead portion 19E2.

[0056] The first lead-out portions 19A1 and 19E1 are located in high-temperature areas of the cell stack 11. The second lead-out portions 19A2 and 19E2 are located in low-temperature areas of the cell stack 11. In this way, by having the first lead-out portions 19A1 and 19E1 and the second lead-out portions 19A2 and 19E2, the connection members 19A and 19E are more likely to distribute current between the first lead-out portion 19A1 and the second lead-out portion 19A2, and between the first lead-out portion 19E1 and the second lead-out portion 19E2. This makes it less likely for the connection members 19 to generate abnormal heat, improving the durability of the cell stack device 10.

[0057] 3, the cross-sectional area of ​​the connecting member 19A may be larger in the first lead portion 19A1 than in the second lead portion 19A2. The cross-sectional area of ​​the connecting member 19E may be larger in the first lead portion 19E1 than in the second lead portion 19E2. This reduces the difference in the amount of current flow between the first lead portions 19A1, 19E1, which have high electrical resistivity at high temperatures, and the second lead portions 19A2, 19E2, which have low electrical resistivity at low temperatures, thereby reducing the problem of current imbalance. Therefore, this embodiment improves the durability of the cell stack device 10.

[0058] Fig. 4 is a plan view of the connecting member shown in Fig. 3. Of the members 17A and 17E shown in Fig. 3, only the member 17A is shown in Fig. 4. For ease of understanding, the first lead portion 19A1 and the second lead portion 19A2, which overlap each other in plan view, are shown side by side in Fig. 4 so as not to overlap each other.

[0059] 4, the first drawn-out portion 19A1 has a first connection surface 19f1 connected to the external device 50. The second drawn-out portion 19A2 has a second connection surface 19f2 connected to the external device 50. The area of ​​the second connection surface 19f2 may be larger than the area of ​​the first connection surface 19f1.

[0060] The electrical resistivity of the coating covering the surface of the second lead portion 19A2 is relatively higher than that of the first lead portion 19A1, which has a higher temperature than the second lead portion 19A2. This reduces the difference in the amount of current flow between the second lead portion 19A2, whose coating has a high electrical resistivity at low temperatures, and the first lead portion 19A1, whose coating has a low electrical resistivity at high temperatures, thereby reducing the problem of current imbalance. Therefore, according to this embodiment, the durability of the cell stack device 10 is increased.

[0061] The first lead portion 19A1 is electrically connected to a terminal 50a led out from the external device 50 by a fastening member, such as a bolt, inserted into the through hole 190. Like the first lead portion 19A1, the second lead portion 19A2 is electrically connected to a terminal 50b led out from the external device 50 by a fastening member inserted into the through hole 190. Note that the first lead portion 19A1 and the second lead portion 19A2 do not necessarily have to have the through hole 190. In such a case, the first lead portion 19A1 and the second lead portion 19A2 can be connected to the respective terminals by a fixing member, such as a clamp.

[0062] A paste-like conductive material may be positioned on connection surfaces 19f of connection member 19A, i.e., first connection surface 19f1 and second connection surface 19f2, thereby reducing contact resistance between first connection surface 19f1 and terminal 50a and between second connection surface 19f2 and terminal 50b and improving conductivity.

[0063] The first lead portion 19A1 and / or the second lead portion 19A2 may be integral with the member 17A or may be separate from the member 17A. For example, if the second lead portion 19A2 is integral with the member 17A, the portion corresponding to the second lead portion 19A2 and the member 17A may be formed into a plate shape, and the portion corresponding to the second lead portion 19A2 may be bent to form the second lead portion 19A2. Furthermore, if the first lead portion 19A1 is separate from the member 17A, the member corresponding to the first lead portion 19A1 may be joined to the surface of the member 17A by welding or the like to form the first lead portion 19A1. Furthermore, the connecting member 19A and the member 17A may be formed by integrating multiple members aligned in the Y-axis direction by welding or the like.

[0064] 2C , connecting member 19B connected to member 17B may have a first lead portion 19B1 located in the high-temperature portion of cell stack 11 and a second lead portion 19B2 located in the low-temperature portion of cell stack 11. Like connecting member 19B, connecting member 19D connected to member 17D may have a first lead portion located in the high-temperature portion of cell stack 11 and a second lead portion located in the low-temperature portion of cell stack 11. Furthermore, connecting member 19C may electrically connect the first lead portion and the second lead portion of connecting member 19B and connecting member 19D, respectively.

[0065] In this way, by having the first and second lead-out portions in the connection members 19A to 19E, the current is more easily dispersed to the first and second lead-out portions, making the connection members 19 less likely to generate abnormal heat and improving the durability of the cell stack device 10.

[0066] 5 is a cross-sectional view showing another example of a connecting member included in the electrochemical cell according to the first embodiment. As shown in FIG. 5, connecting member 19A connected to member 17A has first lead portion 19A1, second lead portion 19A2, and third lead portion 19A3. Connecting member 19E connected to member 17E has first lead portion 19E1, second lead portion 19E2, and third lead portion 19E3.

[0067] The first lead-out portions 19A1 and 19E1 are located in the high-temperature portion of the cell stack 11. The second lead-out portions 19A2 and 19E2 are located in the low-temperature portion of the cell stack 11. The third lead-out portions 19A3 and 19E3 are located midway between the high-temperature portion and the low-temperature portion of the cell stack 11. In this way, since the connection members 19A and 19E have the first lead-out portions 19A1 and 19E1, the second lead-out portions 19A2 and 19E2, and the third lead-out portions 19A3 and 19E3, the current is dispersed to the first lead-out portion 19A1, the second lead-out portion 19A2, and the third lead-out portion 19A3, as well as the first lead-out portion 19E1, the second lead-out portion 19E2, and the third lead-out portion 19E3, making the connection members 19 less likely to generate abnormal heat and improving the durability of the cell stack device 10.

[0068] 5 , the cross-sectional area of ​​the connecting member 19A may be larger in the third lead portion 19A3 than in the second lead portion 19A2, and larger in the first lead portion 19A1 than in the third lead portion 19A3. The cross-sectional area of ​​the connecting member 19E may be larger in the third lead portion 19E3 than in the second lead portion 19E2, and larger in the first lead portion 19E1 than in the third lead portion 19E3. This reduces the problem of current imbalance between the first lead portions 19A1 and 19E1, which have high electrical resistivity at high temperatures, the third lead portions 19A3 and 19E3, which have low electrical resistivity at lower temperatures, and the second lead portions 19A2 and 19E2, which have even lower electrical resistivity at even lower temperatures. Therefore, this embodiment improves the durability of the cell stack device 10.

[0069] Fig. 6 is a plan view of the connecting member shown in Fig. 5. Note that Fig. 6 shows only member 17A as a representative of members 17A and 17E shown in Fig. 5. For ease of understanding, Fig. 6 illustrates first lead portion 19A1, second lead portion 19A2, and third lead portion 19A3, which overlap one another in plan view, arranged so as not to overlap one another.

[0070] 6 , the first lead portion 19A1 has a first connection surface 19f1 connected to a terminal 50a of the external device 50. The second lead portion 19A2 has a second connection surface 19f2 connected to a terminal 50b of the external device 50. The third lead portion 19A3 has a third connection surface 19f3 connected to a terminal 50c of the external device 50. The area of ​​the second connection surface 19f2 may be larger than the area of ​​the third connection surface 19f3. The area of ​​the third connection surface 19f3 may be larger than the area of ​​the first connection surface 19f1.

[0071] This reduces the difference in the amount of current flow between the second lead portion 19A2, whose coating has a high electrical resistivity at low temperatures, the third lead portion 19A3, whose coating has a low electrical resistivity at higher temperatures, and the first lead portion 19A1, whose coating has an even lower electrical resistivity at even higher temperatures, thereby reducing the problem of current imbalance.As a result, this embodiment improves the durability of the cell stack device 10.

[0072] Fig. 7 is a plan view showing another example of the connecting member included in the electrochemical cell according to embodiment 1. As shown in Fig. 7, the end current collecting member 17 may have a first lead portion 19A1 that also serves as the first connection surface 19f1, a second lead portion 19A2 that also serves as the second connection surface 19f2, and a third lead portion 19A3 that also serves as the third connection surface 19f3.

[0073] The first lead-out portion 19A1 is located in a high-temperature portion of the cell stack 11. The second lead-out portion 19A2 is located in a low-temperature portion of the cell stack 11. The third lead-out portion 19A3 is located midway between the high-temperature portion and the low-temperature portion of the cell stack 11. In this way, by having the connecting member 19A have the first lead-out portion 19A1, the second lead-out portion 19A2, and the third lead-out portion 19A3, the current is dispersed to these lead-out portions, improving the durability of the cell stack device 10.

[0074] The area of ​​the second connection surface 19f2 may be larger than the area of ​​the third connection surface 19f3. The area of ​​the third connection surface 19f3 may be larger than the area of ​​the first connection surface 19f1. This reduces the difference in the amount of current flow between the high-temperature portion and the low-temperature portion, even if the electrical resistivity of the second lead-out portion 19A2 increases relatively, thereby reducing the problem of current imbalance. Therefore, according to this embodiment, the durability of the cell stack device 10 is increased.

[0075] <Module> Next, a module 100 according to an embodiment of the present disclosure using the above-described cell stack device 10 will be described with reference to Fig. 8. Fig. 8 is an external perspective view showing an example of a module according to an embodiment. Fig. 8 shows a state in which the front and rear surfaces, which are parts of the storage container 101, have been removed and the cell stack device 10 of the fuel cell stored inside has been removed to the rear.

[0076] 8, the module 100 includes a storage container 101 and a cell stack device 10 housed in the storage container 101. A reformer 102 is disposed above the cell stack device 10.

[0077] The reformer 102 reforms raw fuel such as natural gas or kerosene to generate fuel gas, which is then supplied to the cell 1. The raw fuel is supplied to the reformer 102 through a raw fuel supply pipe 103. The reformer 102 may include a vaporizer 102a that vaporizes water, and a reformer 102b. The reformer 102b includes a reforming catalyst (not shown) and reforms the raw fuel into fuel gas. Such a reformer 102 can perform steam reforming, a highly efficient reforming reaction.

[0078] The fuel gas produced in the reformer 102 is supplied to the gas flow channel 2 a of the cell 1 (see FIG. 1A) through the gas distribution pipe 20 , the gas tank 16 , and the support member 14 .

[0079] Furthermore, in the module 100 having the above-described configuration, the temperature inside the module 100 during normal power generation reaches approximately 500°C to 1000°C due to the combustion of gas and the power generation of the cells 1.

[0080] In such a module 100, as described above, the highly durable cell stack device 10 is housed therein, and thus the module 100 can be made highly durable.

[0081] <Module Enclosure Device> Fig. 9 is an exploded perspective view schematically illustrating an example of a module enclosure device according to an embodiment. The module enclosure device 110 according to this embodiment includes an outer case 111, the module 100 shown in Fig. 8, and auxiliary equipment (not shown). The auxiliary equipment operates the module 100. The module 100 and the auxiliary equipment are housed in the outer case 111. Note that some components are omitted in Fig. 9.

[0082] An exterior case 111 of a module accommodating device 110 shown in Fig. 9 has support columns 112 and an exterior plate 113. A partition plate 114 divides the interior of the exterior case 111 into upper and lower sections. The space above the partition plate 114 in the exterior case 111 is a module accommodating chamber 115 that accommodates the module 100, and the space below the partition plate 114 in the exterior case 111 is an auxiliary equipment accommodating chamber 116 that accommodates auxiliary equipment for operating the module 100. Note that in Fig. 9, the auxiliary equipment accommodated in the auxiliary equipment accommodating chamber 116 is not shown.

[0083] The partition plate 114 also has an air flow port 117 for allowing air from the auxiliary equipment housing chamber 116 to flow toward the module housing chamber 115. The exterior plate 113 that constitutes the module housing chamber 115 has an exhaust port 118 for exhausting air from within the module housing chamber 115.

[0084] In such a module accommodating device 110, as described above, highly durable modules 100 are provided in the module accommodating chamber 115, so that the module accommodating device 110 can be made highly durable.

[0085] Second Embodiment FIG. 10 is a perspective view showing an example of an electrochemical cell according to a second embodiment. The cell 1A shown in FIG. 10 is a flat-plate electrochemical cell having an element unit 3 and conductive members 18 sandwiching the element unit 3. The element unit 3 has a solid electrolyte layer and a first electrode layer (e.g., a hydrogen electrode layer) and a second electrode layer (e.g., an oxygen electrode layer) sandwiching the solid electrolyte layer. The element unit 3 may have a configuration similar to that of the element unit 3 shown in FIG. 1A. The hydrogen electrode layer may be made of the same material as the fuel electrode 5. The oxygen electrode layer may be made of the same material as the air electrode 8. The element unit 3 may also have an intermediate layer located between the solid electrolyte layer and the second electrode layer.

[0086] The conductive member 18 has a first gas flow path 181 through which a hydrogen-containing gas, which is a reducing gas, flows from one end to the other end in a first direction D1. The conductive member 18 also has a second gas flow path 182 through which an oxygen-containing gas flows from one end to the other end in a second direction D2 intersecting the first direction D1. The conductive member 18 is sealed with a sealing member (not shown). In this manner, in an electrochemical cell device having a cell 1A in which the first direction D1 through which the hydrogen-containing gas flows and the second direction D2 through which the oxygen-containing gas, which is an oxidizing gas, flows intersect, for example, the inlet side of the first gas flow path 181 has a higher temperature than the outlet side of the first gas flow path 181, and the outlet side of the second gas flow path 182 has a lower temperature than the inlet side of the second gas flow path 182.

[0087] Fig. 11 is a perspective view showing an example of an electrochemical cell device according to the second embodiment. The cell stack device 10A shown in Fig. 11 is an electrochemical cell device in which flat electrochemical cells each having an element unit 3 and conductive members 18 sandwiching the element unit 3 are stacked. The cell stack device 10A has members 171 and 172, which are end current collecting members 17, located at both ends.

[0088] 11 , the first outlet 19A1 may be located near the inlet of the first gas flow path 181 of the member 171 or near the outlet of the second gas flow path 182. The first outlet 19A1 may also serve as the first connecting surface 19f1 located on the member 171. The second outlet 19A2 may be located in a low-temperature area that is cooler than the first outlet 19A1. The second outlet 19A2 may also serve as the second connecting surface 19f2 located on the member 171. The area of ​​the second connecting surface 19f2 may be larger than the area of ​​the first connecting surface 19f1.

[0089] Thus, the presence of the first lead portion 19A1 and the second lead portion 19A2 facilitates current dispersion, making it less likely that the member 171, which also serves as the connecting member 19, will overheat abnormally. Furthermore, the electrical resistivity of the coating covering the surface of the second lead portion 19A2 is relatively higher than that of the first lead portion 19A1, which has a higher temperature than the second lead portion 19A2. Furthermore, because the area of ​​the second connection surface 19f2 is larger than the area of ​​the first connection surface 19f1, the difference in the amount of current flow between the second lead portion 19A2 and the first lead portion 19A1 is reduced, reducing the risk of current imbalance. Therefore, this embodiment improves the durability of the cell stack device 10A.

[0090] [Third Embodiment] Fig. 12 is a perspective view showing an example of an electrochemical cell according to a third embodiment. The cell 1B shown in Fig. 12 has the same configuration as the cell 1A described above, except for the arrangement of the second gas flow path 182 of the conductive member 18.

[0091] The conductive member 18 has a first gas flow path 181 through which a hydrogen-containing gas, which is a reducing gas, flows from one end to the other end in the first direction D1. The conductive member 18 also has a second gas flow path 182 through which an oxygen-containing gas flows from one end to the other end in the direction along the first direction D1. The conductive member 18 is sealed with a sealing member (not shown) or the like. In this way, in an electrochemical cell device having a cell 1B through which a hydrogen-containing gas and an oxygen-containing gas flow in the first direction D1, for example, a temperature near the outlet of the first gas flow path 181 through which the hydrogen-containing gas flows becomes higher than a temperature near the inlet of the first gas flow path 181.

[0092] Fig. 13 is a perspective view showing an example of an electrochemical cell device according to the third embodiment. The cell stack device 10B shown in Fig. 13 is an electrochemical cell device in which flat electrochemical cells each having an element unit 3 and conductive members 18 sandwiching the element unit 3 are stacked. The cell stack device 10B has members 171 and 172, which are end current collecting members 17, located at both ends.

[0093] 13 , the first outlet 19A1 may be located near the outlet of the first gas flow path 181 of the member 171, and the second outlet 19A2 may be located near the inlet of the first gas flow path 181 of the member 171. The first outlet 19A1 may also serve as the first connecting surface 19f1 located on the member 171. The second outlet 19A2 may also serve as the second connecting surface 19f2 located on the member 171. The area of ​​the second connecting surface 19f2 may be larger than the area of ​​the first connecting surface 19f1.

[0094] Thus, the presence of the first lead portion 19A1 and the second lead portion 19A2 facilitates current dispersion, making it less likely that the member 171, which also serves as the connection member 19, will overheat abnormally. Furthermore, the electrical resistivity of the coating covering the surface of the second lead portion 19A2 is relatively higher than that of the first lead portion 19A1, which has a higher temperature than the second lead portion 19A2. Because the area of ​​the second connection surface 19f2 is larger than the area of ​​the first connection surface 19f1, the difference in the amount of current flow between the second lead portion 19A2 and the first lead portion 19A1 is reduced, reducing the risk of current imbalance. Therefore, this embodiment improves the durability of the cell stack device 10B.

[0095] In Figure 12, a case has been described in which the hydrogen-containing gas and the oxygen-containing gas flow in directions opposite to each other along the first direction D1, but the hydrogen-containing gas and the oxygen-containing gas may also flow in the same direction along the first direction D1.

[0096] Furthermore, in the above-mentioned cells 1A and 1B, the first drawer portion 19A1 and the second drawer portion 19A2 are described as being located on the member 171 side, but the first drawer portion 19A1 and the second drawer portion 19A2 can also be positioned on the member 172 side as on the member 171 side.

[0097] Other Embodiments Next, electrochemical cell devices according to other embodiments will be described.

[0098] In the above-described embodiments, a fuel cell, a fuel cell stack device, a fuel cell module, and a fuel cell device are shown as examples of an "electrochemical cell," "electrochemical cell device," "module," and "module housing device." However, other examples may be an electrolysis cell, an electrolysis cell stack device, an electrolysis module, and an electrolysis device, respectively. The electrolysis cell has a first electrode layer and a second electrode layer, and decomposes water vapor into hydrogen and oxygen, or decomposes carbon dioxide into carbon monoxide and oxygen, when supplied with electric power. Furthermore, in the above-described embodiments, an oxide ion conductor or a hydrogen ion conductor is shown as an example of the electrolyte material of the electrochemical cell, but a hydroxide ion conductor may also be used. Such an electrolysis cell, an electrolysis cell stack device, an electrolysis module, and an electrolysis device have high durability.

[0099] The present disclosure has been described in detail above, but the present disclosure is not limited to the above-described embodiments, and various modifications, improvements, etc. are possible within the scope that does not deviate from the gist of the present disclosure.

[0100] In one embodiment, (1) an electrochemical cell device comprises: a cell stack including a first cell and having a high potential portion and a low potential portion having a lower potential than the high potential portion; and a connection member electrically connected to the high potential portion or the low potential portion of the cell stack, wherein the connection member has a first lead-out portion located in a high temperature portion of the cell stack and a second lead-out portion located in a low temperature portion of the cell stack having a lower temperature than the high temperature portion.

[0101] (2) In the electrochemical cell device of (1) above, the cross-sectional area of ​​the connecting member may be larger in the first lead portion than in the second lead portion.

[0102] (3) In the electrochemical cell device of (1) or (2) above, the first draw-out portion may have a first connection surface connected to an external device, the second draw-out portion may have a second connection surface connected to the external device, and the area of ​​the second connection surface may be larger than the area of ​​the first connection surface.

[0103] (4) In any one of the electrochemical cell devices (1) to (3) above, the electrochemical cell device may include a first gas flow path through which a reducing gas flows from one end to the other end in a first direction intersecting a thickness direction of the first cell, and a second gas flow path through which an oxidizing gas flows in a direction along the first direction, wherein the first outlet portion is located near an outlet of the first gas flow path through which the reducing gas is discharged from inside the cell stack, and the second outlet portion is located near an inlet of the first gas flow path through which the reducing gas is introduced into the cell stack.

[0104] (5) In any one of the electrochemical cell devices (1) to (3) above, the electrochemical cell device may include a first gas flow path through which a reducing gas flows from one end to the other end in a first direction intersecting a thickness direction of the first cell, and a second gas flow path through which an oxidizing gas flows from one end to the other end in a second direction intersecting the first direction, and the first draw-out portion may be located near an inlet of the first gas flow path through which the reducing gas is introduced into the cell stack or near an outlet of the second gas flow path through which the oxidizing gas is discharged from the cell stack.

[0105] In one embodiment, (6) a module includes the electrochemical cell device according to any one of (1) to (5) above, and a container that houses the electrochemical cell device.

[0106] In one embodiment, (7) a module housing device includes the module of (6) above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0107] The disclosed embodiments should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0108] REFERENCE SIGNS LIST 1, 1A, 1B Cell 3 Element section 5 Anode 6 Solid electrolyte layer 7 Intermediate layer 8 Cathode 10, 10A, 10B Cell stack device 11 Cell stack 12 Fixing member 13 Fixing material 14 Support member 15 Support body 16 Gas tank 17 End current collecting member 18 Conductive member 19 Connection member 100 Module 110 Module accommodating device

Claims

1. An electrochemical cell device comprising: a cell stack including a first cell and having a high potential portion and a low potential portion having a lower potential than the high potential portion; and a connection member electrically connected to the high potential portion or the low potential portion of the cell stack, wherein the connection member has a first pull-out portion located in a high temperature portion of the cell stack and a second pull-out portion located in a low temperature portion of the cell stack which has a lower temperature than the high temperature portion.

2. The electrochemical cell device according to claim 1, wherein the cross-sectional area of ​​the connecting member is larger in the first lead-out portion than in the second lead-out portion.

3. The electrochemical cell device according to claim 1 or 2, wherein the first pull-out portion has a first connection surface connected to an external device, and the second pull-out portion has a second connection surface connected to the external device, and an area of ​​the second connection surface is larger than an area of ​​the first connection surface.

4. An electrochemical cell device as described in any one of claims 1 to 3, comprising: a first gas flow path through which a reducing gas flows from one end to the other end in a first direction intersecting the thickness direction of the first cell; and a second gas flow path through which an oxidizing gas flows in a direction along the first direction, wherein the first outlet portion is located near an outlet of the first gas flow path through which the reducing gas is exhausted from the inside of the cell stack, and the second outlet portion is located near an inlet of the first gas flow path through which the reducing gas is introduced into the inside of the cell stack.

5. An electrochemical cell device as described in any one of claims 1 to 3, comprising: a first gas flow path through which a reducing gas flows from one end to the other end in a first direction intersecting with the thickness direction of the first cell; and a second gas flow path through which an oxidizing gas flows from one end to the other end in a second direction intersecting with the first direction, wherein the first pull-out portion is located near an inlet of the first gas flow path through which the reducing gas is introduced into the cell stack, or near an outlet of the second gas flow path through which the oxidizing gas is discharged from the inside of the cell stack.

6. A module comprising: an electrochemical cell device according to any one of claims 1 to 5; and a container for housing the electrochemical cell device.

7. A module housing device comprising: a module according to claim 6; an auxiliary device for operating said module; and an exterior case for housing said module and said auxiliary device.

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