Electroconductive member, electrochemical cell device, module, and module accommodation device

Abstract

This electroconductive member comprises a metal plate, a first porous layer, and a second porous layer. The metal plate has a first surface and a second surface positioned on the opposite side of the first surface, and gas can flow between the first surface and the second surface. The first porous layer is positioned on the first surface. The second porous layer is positioned on the second surface. When the thermal expansion coefficient of the metal plate is α0, the thermal expansion coefficient of the first porous layer is α1, and the thermal expansion coefficient of the second porous layer is α2, α1<α0 and α2<α0, or α1>α0 and α2>α0 are satisfied.

Description

Conductive member, electrochemical cell device, module, and module housing device

[0001] The present disclosure relates to an electrically conductive member, an electrochemical cell device, a module, and a module housing device.

[0002] In recent years, various fuel cell stack devices having multiple fuel cell units have been proposed as next-generation energy sources. A fuel cell unit is a type of electrochemical cell that can generate electric power using a fuel gas such as a hydrogen-containing gas and an oxygen-containing gas such as air.

[0003] JP 2004-273213 A JP 2019-179755 A JP 2013-41717 A

[0004] According to one embodiment, the conductive member includes a metal plate, a first porous layer, and a second porous layer. The metal plate has a first surface and a second surface opposite the first surface, and gas can flow between the first surface and the second surface. The first porous layer is located on the first surface. The second porous layer is located on the second surface. When the thermal expansion coefficient of the metal plate is α0, the thermal expansion coefficient of the first porous layer is α1, and the thermal expansion coefficient of the second porous layer is α2, the thermal expansion coefficients satisfy the relationship α1<α0 and α2<α0, or α1>α0 and α2>α0.

[0005] The electrochemical cell device of the present disclosure includes two or more electrochemical cells each having an element portion, and the conductive member described above.

[0006] The module of the present disclosure includes the electrochemical cell device described above and a container that houses the electrochemical cell device.

[0007] 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.

[0008] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell device according to the first embodiment. FIG. 1B is a plan view of an example of an electrochemical cell included in the electrochemical cell device according to the first embodiment, viewed from the air electrode side. FIG. 1C is an enlarged cross-sectional view of region R shown in FIG. 1A. FIG. 2A is a cross-sectional view showing another example of an electrochemical cell device according to the first embodiment. FIG. 2B is a cross-sectional view showing another example of an electrochemical cell device according to the first embodiment. FIG. 3A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. FIG. 3B is a cross-sectional view taken along line X-X shown in FIG. 3A. FIG. 3C is a top view showing an example of an electrochemical cell device according to the first embodiment. FIG. 4 is an external perspective view showing an example of a module according to the first embodiment. FIG. 5 is an exploded perspective view schematically showing an example of a module housing device according to the first embodiment. FIG. 6 is a perspective view showing an example of an electrochemical cell according to a second embodiment. FIG. 7 is a partial cross-sectional view of the electrochemical cell shown in FIG. 6.

[0009] The above-described fuel cell stack device has room for improvement in performance, such as power generation performance and electrolysis performance.

[0010] Therefore, it is desired to provide a conductive member, an electrochemical cell device, a module, and a module housing device that can improve performance.

[0011] Hereinafter, embodiments of the conductive member, electrochemical cell device, module, and module housing device disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the disclosure is not limited to the embodiments described below.

[0012] 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.

[0013] 1A to 1C, an electrochemical cell 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.

[0014] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell device according to the first embodiment. FIG. 1B is a plan view of an example of an electrochemical cell included in the electrochemical cell device according to the first embodiment, viewed from the air electrode side. FIG. 1C is an enlarged cross-sectional view of region R shown in FIG. 1A. Note that FIGS. 1A to 1C show enlarged views of portions of each component of the electrochemical cell. Hereinafter, the electrochemical cell may also be simply referred to as a cell.

[0015] For ease of understanding, Figures 1A and 1B illustrate a three-dimensional Cartesian coordinate system including a Z axis, with the vertical upward direction as the positive direction and the vertical downward direction as the negative direction. This Cartesian coordinate system may also be shown in other drawings used in the following explanation. Furthermore, components similar to those in the electrochemical cells shown in Figures 1A to 1C are denoted by the same reference numerals, and their explanations will be omitted or simplified.

[0016] 1A, the electrochemical cell device according to this embodiment includes a cell 1A. The cell 1A includes an element section 4A, a conductive member 30, and a flow path member 34. The element section 4A includes a fuel electrode 5, a solid electrolyte layer 6, and a cathode 8.

[0017] The anode 5 is a first electrode that comes into contact with the fuel gas, which is a reducing gas. The anode 5 has gas permeability. The open porosity of the anode 5 may be, for example, in the range of 30% to 50%, particularly 35% to 45%. The open porosity of the anode 5 may also be referred to as the porosity or void ratio of the anode 5.

[0018] 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 contain partially stabilized zirconia. The anode 5 is made of CeO in which La, Nd, or Yb is solid-solved. ２ may include:

[0019] The fuel electrode 5 has a thickness of, for example, 12×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0020] 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.

[0021] 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:

[0022] The solid electrolyte layer 6 has a thickness of, for example, 10×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0023] The air electrode 8 is a second electrode that comes into contact with an oxygen-containing gas. The air electrode 8 has gas permeability. 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.

[0024] 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.

[0025] 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 Sr １－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.

[0026] The air electrode 8 is, for example, 15×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0027] The element unit 4A may also have an intermediate layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. When the element unit 4A has an intermediate layer, the intermediate layer functions, for example, as a diffusion suppression layer. When Sr (strontium) contained in the air electrode 8 diffuses into the solid electrolyte layer 6, SrZrO ３ The intermediate layer is made of SrZrO by making it difficult for Sr to diffuse. ３ This makes it difficult for

[0028] The material of the intermediate layer is not particularly limited as long as it generally prevents diffusion of elements between the air electrode 8 and the solid electrolyte layer 6. The material of the intermediate layer is, for example, cerium oxide (CeO ２ ) may be included. Examples of such rare earth elements include Gd (gadolinium) and Sm (samarium).

[0029] The intermediate layer is, for example, 12×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0030] The cell 1A may further include a constraining layer. The constraining layer may be located between the element portion 4A and the conductive member 30. The constraining layer cooperates with the solid electrolyte layer 6 to make the element portion 4A less susceptible to warping, bending, and the like.

[0031] The material of the constraining layer exhibits a shrinkage rate similar to that of the material of the solid electrolyte layer 6 during firing. The material of the constraining layer may be the same as the material of the solid electrolyte layer 6. The element unit 4A obtained by sandwiching the material of the anode 5 (described later) of the element unit 4A between the material of the solid electrolyte layer 6 and the material of the constraining layer and firing the resulting element unit 4A has little warping or deformation.

[0032] The constraining layer may or may not be gas permeable. When the constraining layer has gas barrier properties comparable to those of the solid electrolyte layer 6, the constraining layer can be partially disposed so as not to obstruct the inflow of fuel gas to the anode 5.

[0033] The constrained layer is, for example, 10 to 12 × 10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0034] The cell 1A may further include a gas diffusion layer. The gas diffusion layer may be located between the anode 5 and the conductive member 30. The gas diffusion layer has gas permeability and allows the fuel gas flowing through a flow path 35 (described later) to pass through to the anode 5. The open porosity of the gas diffusion layer may be in the range of, for example, 30% to 50%, particularly 35% to 45%.

[0035] The material of the gas diffusion layer may be a porous conductive ceramic, such as a ceramic containing calcium oxide, magnesium oxide, or stabilized zirconia or partially stabilized zirconia in which a rare earth element oxide is solid-solved, and Ni and / or NiO. The rare earth element oxide may contain a plurality of rare earth elements selected from, for example, Sc, Y, La, Nd, Sm, Gd, Dy, and Yb.

[0036] The gas diffusion layer is, for example, 12×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0037] The conductive member 30 has an adhesive 31 as a first porous layer, a metal plate 32, and a deformation suppression layer 33 as a second porous layer.

[0038] The adhesive 31 is located between the element portion 4A and the first surface 321 of the metal plate 32. The adhesive 31 bonds the element portion 4A and the metal plate 32 together, and fixes the element portion 4A to the metal plate 32.

[0039] The adhesive 31 may be conductive. For example, the adhesive 31 may be a mixture of conductive particles such as Ni and TiO ２ , rare earth element oxides (Y ２ O ３ , CeO ２ etc.), transition metal oxides (Fe ２ O ３ The inorganic oxide may include inorganic oxides such as SiO 2 , CuO, etc.

[0040] The adhesive 31 may be gas permeable. When the adhesive 31 is gas permeable, the adhesive 31 may be positioned so as to cover an opening 32 a described later. Furthermore, the solid electrolyte layer 6 may be positioned so as to cover the side surface of the adhesive 31.

[0041] As shown in FIG. 2A , a sealant 9 different from the solid electrolyte layer 6 may be positioned on the side surfaces of the adhesive 31 and the anode 5. The material of the sealant 9 may be dense glass or ceramic. The material of the sealant 9 may be, for example, amorphous glass or crystallized glass. Examples of crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO-based, La ２ O ３ -B ２ O ３ -ZnO-based, SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２- An MgO-based material may be used. The sealing material 9 may have electrical insulating properties.

[0042] The material of the adhesive 31 may have gas sealing properties. When the material of the adhesive 31 has gas sealing properties, the adhesive 31 may be positioned so as to contact a first surface 321 of the metal plate 32 where the openings 32a described below are not located. In this case, the adhesive 31 may be a dense body having through holes at the positions of the openings 32a.

[0043] The adhesive 31 may be formed as a single layer using a single material, or may be formed as a laminate of multiple materials. The adhesive 31 may be integrated with the anode 5. In other words, the anode 5 may be the first porous layer that also serves as the adhesive 31. The first porous layer may include the gas diffusion layer described above.

[0044] The metal plate 32 has a first surface 321 and a second surface 322 located at both ends in the thickness direction (Y-axis direction).

[0045] The metal plate 32 is electrically conductive. Alternatively, the metal plate 32 may be a member made of a metal containing chromium, for example. The metal plate 32 may be stainless steel, such as ferritic stainless steel or austenitic stainless steel, which has high heat resistance. The metal plate 32 may be a nickel-chromium alloy or an iron-chromium alloy, for example. The metal plate 32 may contain a metal oxide, for example. Alternatively, the metal plate 32 may have a coating 320 covering the surface, as shown in FIG. 1C . The metal plate 32 does not have to have a coating 320 on the surface.

[0046] The metal plate 32 also has an opening 32a. The opening 32a is a through-hole that penetrates between the first surface 321 and the second surface 322. The fuel gas flowing through a flow path 35 (described later) is supplied to the fuel electrode 5 of the element section 4A through the opening 32a. The diameter of the opening 32a may be, for example, 0.1 mm to 0.5 mm, particularly 0.3 mm to 0.4 mm. The aperture ratio in the region where the opening 32a is formed may be, for example, 10% or more. The metal plate 32 may have a coating 320 that covers the wall surface of the opening 32a. The metal plate 32 does not need to have the coating 320 on the wall surface of the opening 32a.

[0047] The metal plate 32 is, for example, 13×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0048] The metal plate 32 may be gas permeable, for example. In such a case, the metal plate 32 does not need to have the opening 32a.

[0049] The deformation suppression layer 33 is located so as to contact the second surface 322 of the metal plate 32. The deformation suppression layer 33 is located between the metal plate 32 and the flow path member 34. The deformation suppression layer 33 cooperates with the adhesive 31 to make the metal plate 32 less susceptible to warping, bending, and the like.

[0050] The deformation suppression layer 33 may be electrically conductive. The electrical conductivity of the deformation suppression layer 33 may be, for example, 10 to 1000 S / m.

[0051] The material of the deformation suppression layer 33 is, for example, ZrO in which Y is dissolved. ２ The deformation suppression layer 33 may be, for example, TiO in which Sr or Ni is solid-solved. ２ The material of the deformation suppression layer 33 may be the same as the material of the adhesive 31.

[0052] The deformation suppression layer 33 may be gas permeable. When the deformation suppression layer 33 is gas permeable, the deformation suppression layer 33 may be positioned so as to cover the opening 32a.

[0053] The material of the deformation suppression layer 33 may also have gas sealing properties. When the material of the deformation suppression layer 33 has gas sealing properties, the deformation suppression layer 33 may be positioned so as to contact the second surface 322 of the metal plate 32 where the openings 32a are not located. In this case, the deformation suppression layer 33 may be a dense body having through holes at the positions of the openings 32a.

[0054] The deformation suppression layer 33 may be formed as a single layer using a single material, or may be formed as a laminate of multiple materials.

[0055] The deformation suppression layer 33 has, for example, a thermal expansion coefficient (linear expansion coefficient) closer to that of the adhesive 31 than to that of the metal plate 32. By sandwiching the metal plate 32 between the adhesive 31 and the deformation suppression layer 33, which have similar thermal expansion coefficients (linear expansion coefficients), the conductive member 30 makes the metal plate 32 less likely to warp or bend.

[0056] Here, if the thermal expansion coefficient of the metal plate 32 is α0, the thermal expansion coefficient of the adhesive material 31, which is the first porous layer, is α1, and the thermal expansion coefficient of the deformation suppression layer 33, which is the second porous layer, is α2, the conductive member 30 may have the relationship α1<α0 and α2<α0, for example. This makes it less likely for the metal plate 32 to warp or bend, thereby improving the adhesion between the metal plate 32 and the element section 4A. Therefore, a cell stack device 10 having such a conductive member 30 can improve power generation performance. In this case, α1 and α2 may be, for example, 10 to 12×10 －６ / K.

[0057] Furthermore, the conductive member 30 may have a metal plate 32, adhesive 31, and deformation suppression layer 33 having the relationships α1 > α0 and α2 > α0. Even in this case, warping or deflection of the metal plate 32 is less likely to occur, thereby improving adhesion between the metal plate 32 and the element section 4A. Therefore, a cell stack device 10 having such a conductive member 30 can improve power generation performance. Note that the values ​​of α0, α1, and α2 can be adjusted, for example, by changing the composition of the conductive member 30.

[0058] Furthermore, |α1-α2| may be smaller than both |α0-α1| and |α0-α2|. This further reduces the risk of warping or bending of the metal plate 32, thereby enabling a cell stack device 10 including such a conductive member 30 to further improve power generation performance. The material of the deformation suppression layer 33, which is the second porous layer, may be the same as or different from the material of the adhesive 31, which is the first porous layer, as long as the relationship between α1, α2, and α3 is satisfied.

[0059] The thermal expansion coefficient of each component of the conductive member 30 can be obtained, for example, by analyzing the composition of the conductive member 30, preparing a test piece based on the analyzed composition, and measuring the test piece by thermomechanical analysis (TMA) in accordance with JIS R 1618-1994.

[0060] The flow path member 34 is located on the second surface 322 side of the metal plate 32. The flow path member 34 is fixed and electrically joined by, for example, welding or the like at the contact portion with the second surface 322. The flow path member 34 may be fixed and electrically joined to the metal plate 32 with a conductive sealing material, brazing material, or the like. The space located between the deformation suppression layer 33 and the flow path member 34 is a flow path 35 through which the fuel gas flows. The fuel gas flowing through the flow path 35 permeates the conductive member 30 and is supplied to the anode 5. The flow path member 34 may have one or more protrusions protruding toward the deformation suppression layer 33.

[0061] The flow path member 34 is further fixed and electrically joined to the current collecting member 36 by welding or the like. The current collecting member 36 may be fixed and electrically joined to the flow path member 34 by a conductive sealing material, brazing material, or the like. The current collecting member 36 is fixed and electrically joined to the air electrode 8 of the adjacent cell 1A via an adhesive 40. The space located between the current collecting member 36 and the flow path member 34 is a flow path 37 through which an oxygen-containing gas flows. The oxygen-containing gas flowing through the flow path 37 passes through the adhesive 40 from the slits in the current collecting member 36 and is supplied to the air electrode 8 of the adjacent cell 1A.

[0062] The flow path member 34 and the current collecting member 36 are made of a dense metal or alloy. The flow path member 34 makes it difficult for the fuel gas flowing through the flow path 35 and the oxygen-containing gas flowing through the flow path 37 to leak. The flow path member 34 and the current collecting member 36 may have a coating layer. For example, the surface of the flow path member 34 facing the flow path 35 may have a coating layer that is resistant to reduction. Furthermore, the surface of the flow path member 34 facing the flow path 37 may have a coating layer that is resistant to oxidation. These coating layers may be electrically conductive.

[0063] The shapes of the flow path member 34 and the current collecting member 36 are not limited to those shown in Fig. 1A. The flow path member 34 and the current collecting member 36 may have any shape as long as they electrically connect adjacent cells 1A and prevent leakage of fuel gas and oxygen-containing gas. For example, as shown in Fig. 2B, the flow path member 34 may be integrated with the current collecting member 36 and have a first convex portion protruding toward the deformation suppression layer 33 and a second convex portion protruding toward the opposite side from the first convex portion.

[0064] <Configuration of Cell Stack Device> Next, an electrochemical cell device according to this embodiment using the above-described cell 1A will be described with reference to Figures 3A to 3C. Figure 3A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. Figure 3B is a cross-sectional view taken along line X-X shown in Figure 3A. Figure 3C is a top view showing an example of an electrochemical cell device according to the first embodiment.

[0065] As shown in Figure 3A, the cell stack device 10 comprises a cell stack 11 having multiple cells 1A arranged (stacked) in the thickness direction of the element section 4A (the Y-axis direction shown in Figure 1A), and a fixing member 12.

[0066] The fixing member 12 has a fixing material 13 and a support member 14. The support member 14 supports the cell 1A. The fixing material 13 fixes the cell 1A 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.

[0067] 3B, the support body 15 has insertion holes 15a into which the lower ends of the cells 1A are inserted. The lower ends of the cells 1A and the inner walls of the insertion holes 15a are joined with fixing material 13.

[0068] The gas tank 16 has an opening for supplying a reaction gas to the cells 1A 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.

[0069] In the example shown in Fig. 3A, fuel gas is stored in an internal space 22 (see Fig. 3B) formed by a support 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 flow path 35 (see Fig. 1A) inside the cell 1A. The fuel gas supplied to the gas tank 16 is generated in a reformer 102 (see Fig. 4), which will be described later.

[0070] 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.

[0071] The example shown in Fig. 3A 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 1A. 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.

[0072] The shape of the insertion hole 15a is, 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 1A, i.e., the thickness direction (Y-axis direction shown in FIG. 1A ), is 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 is greater than the length of the cell 1A in the width direction (X-axis direction shown in FIG. 1A ).

[0073] 3B, the joints between the inner walls of the insertion holes 15a and the lower ends of the cells 1A are filled with and solidified with fixing material 13. This bonds and fixes the inner walls of the insertion holes 15a to the lower ends of the multiple cells 1A, and also bonds and fixes the lower ends of the cells 1A to each other. The gas flow paths 2a of each cell 1A communicate with the internal space 22 of the support member 14 at their lower ends.

[0074] 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.

[0075] 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-based, La ２ O ３ -B ２ O ３ -ZnO-based, SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２ - MgO-based materials may also be used.

[0076] 3B, a conductive member 18 is interposed between adjacent cells 1A among the plurality of cells 1A. The conductive member 18 electrically connects one adjacent cell 1A to the other adjacent cell 1A in series. More specifically, the conductive member 18 connects the fuel electrode 5 of one cell 1A to the air electrode 8 of the other cell 1A. The conductive member 18 may be the conductive member 30 shown in FIG. 1A or may be a member separate from the conductive member 30.

[0077] 3B, an end current collecting member 17 is electrically connected to the cell 1A located at the outermost position in the arrangement direction of the multiple cells 1A. The end current collecting member 17 is connected to a conductive portion 19 that protrudes outside the cell stack 11. The conductive portion 19 collects electricity generated by the cells 1A and outputs it to the outside. Note that the end current collecting member 17 is not shown in FIG. 3A.

[0078] 3C, the cell stack device 10 may be a single battery in which two cell stacks 11A, 11B are connected in series. In such a case, the conductive portion 19 of the cell stack device 10 may have a positive terminal 19A, a negative terminal 19B, and a connection terminal 19C.

[0079] The positive terminal 19A is a positive electrode when the power generated by the cell stack 11 is output to the outside, and is electrically connected to the positive-side end current collecting member 17 of the cell stack 11A. The negative terminal 19B is a negative electrode when the power generated by the cell stack 11 is output to the outside, and is electrically connected to the negative-side end current collecting member 17 of the cell stack 11B.

[0080] The connection terminal 19C electrically connects the end current collecting member 17 on the negative electrode side of the cell stack 11A to the end current collecting member 17 on the positive electrode side of the cell stack 11B.

[0081] Although not shown in Figures 3A to 3C, the cell stack device 10 may also be provided with a second gas tank at the top of the cell stack 11, which fixes the upper ends of multiple cells 1A and collects gas discharged from the flow path 35 inside the cells 1A.

[0082] <Module> Next, a module according to an embodiment of the present disclosure using the above-described cell stack device 10 will be described with reference to Fig. 4. Fig. 4 is an external perspective view showing an example of a module according to the first embodiment. Fig. 4 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.

[0083] 4, 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.

[0084] The reformer 102 reforms raw fuel such as natural gas or kerosene to generate fuel gas, which is then supplied to the cell 1A. 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.

[0085] The fuel gas produced in the reformer 102 is supplied to the flow path 35 of the cell 1A (see FIG. 1A) through the gas distribution pipe 20, the gas tank 16, and the support member 14.

[0086] Note that, when the cell stack device 10 includes a second gas tank above the cell stack 11, the reformer 102 may be disposed in a location other than above the cell stack device 10. The raw fuel supply pipe 103, the gas circulation pipe 20, and the like may be disposed as appropriate depending on the arrangement of the cell stack device 10 and the reformer 102.

[0087] Furthermore, in the module 100 having the above-described configuration, the temperature inside the module 100 during normal power generation becomes approximately 500° C. to 1000° C. as the cells 1A generate power.

[0088] In such a module 100, as described above, by accommodating the cell stack device 10 that improves power generation performance, the module 100 can be made to have improved power generation performance.

[0089] <Module Enclosure Device> Fig. 5 is an exploded perspective view schematically illustrating an example of a module enclosure device according to the first embodiment. The module enclosure device 110 according to this embodiment includes an outer case 111, the module 100 shown in Fig. 4, 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. 5.

[0090] An exterior case 111 of a module accommodating device 110 shown in Fig. 5 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. 5, the auxiliary equipment accommodated in the auxiliary equipment accommodating chamber 116 is omitted from the illustration.

[0091] 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.

[0092] In such a module accommodating device 110, as described above, by providing the module 100 with improved power generation performance in the module accommodating chamber 115, the module accommodating device 110 can be made to have improved power generation performance.

[0093] Second Embodiment Fig. 6 is a perspective view showing an example of an electrochemical cell according to a second embodiment, and Fig. 7 is a partial cross-sectional view of the electrochemical cell shown in Fig. 6 .

[0094] 6 and 7 , cell 1B includes an element unit 4B, a conductive member 30, and flow path members 91 and 92. Element unit 4B includes an anode 5, a solid electrolyte layer 6, and a cathode 8. The materials of the anode 5, the solid electrolyte layer 6, and the cathode 8 may be the same as the materials of the anode 5, the solid electrolyte layer 6, and the cathode 8 of cell 1A described above. Furthermore, element unit 4B may include an intermediate layer 7 located between the solid electrolyte layer 6 and the cathode 8. The material of this intermediate layer 7 may be the same as the material of any intermediate layer included in cell 1A described above.

[0095] The flow path members 91, 92 have gas flow paths that supply gas to the fuel electrode 5 or the air electrode 8, and also electrically connect adjacent cells 1B to each other. In an electrochemical cell device in which a plurality of flat plate-type cells are stacked, for example, a plurality of cells 1B are electrically connected to each other by the flow path members 91, 92, which are adjacent metal layers.

[0096] 7, cell 1B has a sealing material that airtightly seals the fuel gas flow path and the oxygen-containing gas flow path of the flat cell stack. The sealing material is a fixing member 96 for the cell, and has a bonding material 93 and support members 94 and 95 that serve as a frame. The bonding material 93 may be glass or a metal material such as silver solder.

[0097] The support member 94 may be a so-called separator that separates the fuel gas flow path from the oxygen-containing gas flow path. The material of the support members 94, 95 may be, for example, a conductive metal or an insulating ceramic. Either or both of the support members 94, 95 may be made of an insulating material. If the support member 94 is made of metal, the support member 94 may be integrated with the flow path member 92. If the support member 95 is made of metal, the support member 95 may be integrated with the flow path member 91.

[0098] One of the support members 94 and 95 is insulating, and electrically insulates the two flow path members 91 and 92 that sandwich the flat cell from each other.

[0099] In the cell 1B shown in FIG. 7 , the conductive member 30 is located between the element unit 4B and the flow path member 91. The conductive member 30 has a first porous layer and a deformation suppression layer 33 as a second porous layer. In the cell 1B shown in FIG. 7 , the first porous layer of the conductive member 30 is the fuel electrode 5 that contacts the first surface 321 of the metal plate 32. The conductive member 30 of the cell 1B may have an adhesive as the first porous layer between it and the fuel electrode 5. The adhesive bonds the element unit 4B and the metal plate 32 and fixes the element unit 4B to the metal plate 32. The first porous layer may include the gas diffusion layer described above.

[0100] The metal plate 32 may be made of the same material as the metal plate 32 of the electrochemical cell according to the first embodiment. The metal plate 32 may be, for example, a conductive metal member and may contain chromium. The metal plate 32 may contain, for example, a metal oxide. Furthermore, the metal plate 32 may or may not have a coating covering the surface.

[0101] The metal plate 32 also has an opening 32 a. The opening 32 a is a through-hole that penetrates between the first surface 321 and the second surface 322. The metal plate 32 may or may not have a coating that covers the wall surface of the opening 32 a.

[0102] The metal plate 32 is, for example, 13×10 －６ The material may have a thermal expansion coefficient (linear expansion coefficient) of about 1 / K.

[0103] The metal plate 32 may be, for example, gas permeable. In such a case, the metal plate 32 does not need to have the opening 32a.

[0104] The deformation suppression layer 33 is positioned so as to contact the second surface 322 of the metal plate 32. The deformation suppression layer 33 is positioned between the metal plate 32 and the flow path member 91. In the cell 1B shown in FIG. 7 , the deformation suppression layer 33 cooperates with the fuel electrode 5, which is the first porous layer, to make the metal plate 32 less likely to warp or bend.

[0105] In the cell 1B, the deformation suppression layer 33 of the conductive member 30 is conductive. The deformation suppression layer 33 electrically connects the flow path member 91 and the element section 4B. The material of the deformation suppression layer 33 may be the same as the material of the fuel electrode 5.

[0106] The deformation suppression layer 33 may be gas permeable. If the deformation suppression layer 33 is gas permeable, the deformation suppression layer 33 may be positioned so as to cover the opening 32a. The material of the deformation suppression layer 33 may also have gas sealing properties. If the material of the deformation suppression layer 33 is gas sealing properties, the deformation suppression layer 33 may be positioned so as to contact the second surface 322 of the metal plate 32 where the opening 32a is not located. In this case, the deformation suppression layer 33 may be a dense body having through holes at the positions of the openings 32a.

[0107] The deformation suppression layer 33 may be formed as a single layer using a single material, or may be formed as a laminate of multiple materials.

[0108] The deformation suppression layer 33 has, for example, a thermal expansion coefficient (linear expansion coefficient) closer to that of the adhesive 31 than to that of the metal plate 32. By sandwiching the metal plate 32 between the adhesive 31 and the deformation suppression layer 33, which have similar thermal expansion coefficients (linear expansion coefficients), the conductive member 30 makes the metal plate 32 less likely to warp or bend.

[0109] If the thermal expansion coefficient of the metal plate 32 is α0, the thermal expansion coefficient of the fuel electrode 5 (first porous layer) is α1, and the thermal expansion coefficient of the deformation suppression layer 33 (second porous layer) is α2, the conductive member 30 may have the relationship α1<α0 and α2<α0, for example. This makes it less likely for the metal plate 32 to warp or bend, thereby improving the adhesion between the metal plate 32 and the element section 4B. Therefore, a cell stack device including such a conductive member 30 can improve power generation performance. In this case, α1 and α2 are, for example, 10 to 12×10 －６ / K.

[0110] Furthermore, the conductive member 30 may have a metal plate 32, an anode 5, and a deformation suppression layer 33 having the relationships α1 > α0 and α2 > α0. Even in this case, warping or deflection of the metal plate 32 is less likely to occur, which improves adhesion between the metal plate 32 and the element section 4B, and a cell stack device having such a conductive member 30 can improve power generation performance. Note that the values ​​of α0, α1, and α2 can be adjusted, for example, by changing the composition of the conductive member 30.

[0111] Furthermore, |α1-α2| may be smaller than both |α0-α1| and |α0-α2|. This further reduces the risk of warping or bending of the metal plate 32, thereby enabling a cell stack device including such a conductive member 30 to further improve power generation performance. The material of the deformation suppression layer 33, which is the second porous layer, may be the same as or different from the material of the anode 5, which is the first porous layer, as long as the relationship between α1, α2, and α3 is satisfied.

[0112] [Other Embodiments] 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 and a second electrode, 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 can improve electrolysis performance.

[0113] 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.

[0114] In one embodiment, (1) the conductive member comprises a metal plate having a first surface and a second surface located opposite the first surface, allowing gas to flow between the first surface and the second surface, a first porous layer in contact with the first surface, and a second porous layer in contact with the second surface, wherein when the thermal expansion coefficient of the metal plate is α0, the thermal expansion coefficient of the first porous layer is α1, and the thermal expansion coefficient of the second porous layer is α2, the relationship is α1<α0 and α2<α0, or α1>α0 and α2>α0.

[0115] (2) In the conductive member of (1) above, the metal plate may have a plurality of openings that penetrate the first surface and the second surface.

[0116] (3) In the conductive member of (1) or (2) above, the first porous layer and the second porous layer may be conductive.

[0117] (4) In the conductive member of any one of (1) to (3) above, the first porous layer, the second porous layer, and the metal plate may have the relationship α1<α0 and α2<α0.

[0118] (5) In any one of the conductive members (1) to (4) above, |α1-α2| may be smaller than both |α0-α1| and |α0-α2|.

[0119] In one embodiment, (6) an electrochemical cell device includes: two or more electrochemical cells each having an element portion; and a conductive member selected from any one of (1) to (5) above.

[0120] In one embodiment, (7) a module includes the electrochemical cell device of (6) above, and a container that houses the electrochemical cell device.

[0121] In one embodiment, (8) a module housing device includes the module of (7) above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0122] 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.

[0123] 1A, 1B Cell 4A, 4B Element portion 9 Sealing material 10 Cell stack device 30 Conductive member 31 Adhesive material 32 Metal plate 33 Deformation suppression layer 100 Module 110 Module accommodating device

Claims

1. A metal plate having a first surface and a second surface located opposite to the first surface, and allowing gas to flow between the first surface and the second surface; a first porous layer in contact with the first surface; a second porous layer in contact with the second surface; Equipped with When the thermal expansion coefficient of the metal plate is α0, the thermal expansion coefficient of the first porous layer is α1, and the thermal expansion coefficient of the second porous layer is α2, The relationship is α1<α0 and α2<α0, or α1>α0 and α2>α0. Conductive material.

2. The metal plate has a plurality of openings penetrating the first surface and the second surface. The conductive member according to claim 1 .

3. The first porous layer and the second porous layer are electrically conductive. The conductive member according to claim 1 .

4. The first porous layer, the second porous layer, and the metal plate are The relationship is α1<α0 and α2<α0. The conductive member according to claim 1 .

5. |α1-α2| is smaller than both |α0-α1| and |α0-α2| The conductive member according to claim 1 .

6. Two or more electrochemical cells each having an element portion; The conductive member according to any one of claims 1 to 5. An electrochemical cell device comprising:

7. The electrochemical cell device according to claim 6 ; A container for housing the electrochemical cell device; A module comprising:

8. A module according to claim 7; Auxiliary equipment for operating the module; an exterior case that houses the module and the auxiliary equipment; A module housing device comprising: