Electrochemical cell, electrochemical cell device, module, and module housing device

Abstract

An electrochemical cell according to the present invention comprises an element part and a passage member. The passage member has a first flat part that is opposite the element part and a plurality of protrusions that protrude from the first flat part toward the element part. The plurality of protrusions include at least two first protrusions that have a first length in a first direction that runs along the first flat part and are aligned in the first direction.

Description

Electrochemical cell, electrochemical cell device, module, and module housing device

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

[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] International Publication No. 2020 / 218431

[0004] An electrochemical cell according to one aspect of the embodiment includes an element portion and a flow path member. The flow path member has a first flat portion facing the element portion and a plurality of protruding portions protruding from the first flat portion toward the element portion. The plurality of protruding portions have a first length in a first direction along the first flat portion and include two or more first protruding portions aligned in the first direction.

[0005] The electrochemical cell device of the present disclosure also includes a cell stack including the electrochemical cell 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 according to an embodiment. FIG. 1B is a plan view of an example of an electrochemical cell according to an embodiment, viewed from the air electrode side. FIG. 1C is a plan view of an example of an electrochemical cell according to an embodiment, viewed from the flow path member side. FIG. 1D is a cross-sectional view showing another example of an electrochemical cell according to an embodiment. FIG. 2A is an enlarged plan view of region R1 shown in FIG. 1C. FIG. 2B is a cross-sectional view taken along line A-A shown in FIG. 2A. FIG. 3A is a perspective view showing an example of an electrochemical cell device according to an 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 an embodiment. FIG. 4 is an external perspective view showing an example of a module according to an embodiment. FIG. 5 is an exploded perspective view schematically showing an example of a module housing device according to an embodiment. FIG. 6A is a plan view showing an example of a first convex portion included in a flow path member. FIG. 6B is a plan view showing an example of a first convex portion included in a flow path member. FIG. 6C is a plan view showing an example of a first convex portion included in a flow path member. FIG. 7A is a plan view showing an example of a third convex portion included in a flow path member. 7B and 7C are plan views showing an example of a third convex portion included in the flow path member.

[0009] The above-described fuel cell stack device has room for improvement, for example, in terms of improving power generation performance.

[0010] Therefore, it has been proposed to provide an electrochemical cell, an electrochemical cell device, a module, and a module housing device that can improve performance.

[0011] Hereinafter, embodiments of an electrochemical cell, 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.

[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 an 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 according to an embodiment. FIG. 1B is a plan view of an example of an electrochemical cell according to an embodiment, viewed from the air electrode side. FIG. 1C is a plan view of an example of an electrochemical cell according to an embodiment, viewed from the flow path member side. 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] 1A to 1C illustrate a three-dimensional Cartesian coordinate system including a Z-axis, with the vertically upward direction being the positive direction and the vertically downward direction being the negative direction. This Cartesian coordinate system may also be shown in other drawings used in the following explanation. Furthermore, the same reference numerals are used to designate components similar to those of the electrochemical cells shown in FIGS. 1A to 1C, and their explanations will be omitted or simplified.

[0016] 1A , the electrochemical cell device according to this embodiment includes a cell 1. The cell 1 includes an element section 3, a support member 2, and a flow path member 30. The element section 3 includes a cathode 8, a solid electrolyte layer 6, and a fuel electrode 5.

[0017] The air electrode 8 is a first 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.

[0018] 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.

[0019] 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.

[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 anode 5 is a second 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.

[0023] 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. ２ and 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:

[0024] The element unit 3 may also have an intermediate layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. When the element unit 3 has an intermediate layer, the intermediate layer functions, for example, as a diffusion suppression layer. When elements such as Sr (strontium) contained in the air electrode 8 diffuse into the solid electrolyte layer 6, SrZrO ３ The intermediate layer makes it difficult for specific elements such as Sr to diffuse, resulting in a resistance layer such as SrZrO ３ This makes it difficult for a resistive layer such as the above to form.

[0025] 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) 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).

[0026] The cell 1 may further include a constraining layer. The constraining layer may be located between the element portion 3 and the support member 2. The constraining layer cooperates with the solid electrolyte layer 6 to make the element portion 3 less susceptible to warping, bending, and the like.

[0027] 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 3 obtained by sandwiching the material of the anode 5 of the element unit 3 between the material of the solid electrolyte layer 6 and the material of the constraining layer and firing the resulting element unit 3 has little warping or deformation.

[0028] 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.

[0029] The cell 1 may further include a gas diffusion layer. The gas diffusion layer may be located between the anode 5 and the support member 2. The gas diffusion layer has gas permeability and allows the fuel gas flowing through a flow path 2a (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%.

[0030] 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.

[0031] The cell 1 may further include an adhesive material. The adhesive material may be located between the element portion 3 and the support member 2. The adhesive material bonds the element portion 3 and the support member 2 together, and fixes the element portion 3 to the support member 2.

[0032] The adhesive may be conductive. For example, the adhesive 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.

[0033] The adhesive may be gas permeable. The solid electrolyte layer 6 may be positioned so as to cover the side surface of the adhesive.

[0034] The support member 2 is electrically conductive. The support member 2 may be, for example, a metal plate containing chromium. The support member 2 may be, for example, a stainless steel such as a ferritic stainless steel or an austenitic stainless steel having high heat resistance. The support member 2 may be, for example, a nickel-chromium alloy or an iron-chromium alloy. The support member 2 may contain, for example, a metal oxide. The support member 2 may have a coating covering the surface. The support member 2 does not have to have a coating on the surface.

[0035] The support member 2 may also have openings penetrating in the thickness direction (Y-axis direction). Fuel gas flowing through a flow path 2a, which will be described later, is supplied to the fuel electrode 5 of the element section 3 through these openings. The diameter of the openings 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 openings are formed may be, for example, 10% or more. The support member 2 may have a coating covering the wall surfaces of the openings. The support member 2 does not need to have a coating on the wall surfaces of the openings.

[0036] The support member 2 may be gas permeable, for example. In such a case, the support member 2 does not need to have an opening penetrating in the thickness direction (Y-axis direction).

[0037] The flow path member 30 is located between the air electrode 8 of the element section 3 and the support member 2. The material of the flow path member 30 may be a dense metal or alloy. The flow path member 30 has a surface 31 and a surface 32. The flow path member 30 makes it difficult for the oxygen-containing gas flowing on the surface 31 side and the fuel gas flowing on the surface 32 side to leak. The flow path member 30 may have a coating layer. For example, the surface 31 of the flow path member 30 may have a coating layer that is resistant to oxidation, and the surface 32 may have a coating layer that is resistant to reduction. These coating layers may be conductive.

[0038] The flow path member 30 is fixed and electrically joined to the support member 2 by, for example, welding or the like at the contact portion. The flow path member 30 may be fixed and electrically joined to the support member 2 by a conductive sealing material, brazing material, or the like. A flow path 2a through which the fuel gas flows is located between the surface 32 of the flow path member 30 and the support member 2. The fuel gas flowing through the flow path 2a permeates the support member 2 and is supplied to the anode 5. The flow path member 30 may have one or more protrusions protruding from the surface 32 toward the support member 2.

[0039] The surface 31 is fixed to the air electrode 8 via, for example, a conductive adhesive and electrically joined thereto. A space is located between the flow path member 30 and the air electrode 8, through which an oxygen-containing gas flows.

[0040] 1C , the surface 31 of the flow path member 30 facing the air electrode 8 may have a first portion 311 and a second portion 312. The first portion 311 is located in the center in the X-axis direction facing the air electrode 8. The second portion 312 is located at both ends in the X-axis direction adjacent to the first portion 311. The first portion 311 and the second portion 312 are different in distance from the air electrode 8. For example, the second portion 312 may be located farther from the first portion 311 than the air electrode 8. The surface 31 may have an intermediate portion located between the first portion 311 and the second portion 312.

[0041] The flow path member 30 has a first end 41 and a second end 42 located at opposite ends in the Z-axis direction. The oxygen-containing gas flows, for example, from the first end 41 toward the second end 42 along the surface 31. Details of the flow path member 30 will be described later.

[0042] 1D is a cross-sectional view showing another example of an electrochemical cell according to an embodiment. As shown in FIG. 1D, a sealant 9 different from the solid electrolyte layer 6 may be located on the side surface of the fuel electrode 5 and the solid electrolyte layer 6. 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 ３System, 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.

[0043] <Details of Flow Channel Member> Fig. 2A is an enlarged plan view of region R1 shown in Fig. 1C. Fig. 2B is a cross-sectional view taken along line A-A in Fig. 2A. As shown in Figs. 2A and 2B, the first portion 311 of the flow channel member 30 has a flat portion 31a as a first flat portion and a plurality of protruding portions 31b. The flat portion 31a is positioned so as to face the element portion 3.

[0044] The multiple protrusions 31b are positioned so as to protrude from the flat portion 31a toward the element unit 3. As shown in FIG. 2B , the protrusions 31b have apexes 31c facing the element unit 3. The apexes 31c may be in contact with the element unit 3. This increases the amount of current per unit time flowing between the air electrode 8 of the element unit 3 and the flow path member 30, improving power generation performance. The apex 31c may have a flat portion serving as a second flat portion. This increases the contact area between the air electrode 8 of the element unit 3 and the flow path member 30, further improving the power generation performance of the cell 1. Here, the flat portion 31a serving as the first flat portion and the flat portion serving as the second flat portion located at the apex 31c refer to portions that are generally parallel to the surface of the element unit 3 that faces the flow path member 30. The flat portion may have irregularities. The flat portion may have irregularities with a maximum height of, for example, one-fifth or less of the height of the protrusions 31b. Flat portion 31a may further have a maximum height of, for example, 3 μm or less. Top portion 31c may have a curved surface that protrudes toward element portion 3 or toward the opposite side from element portion 3. When top portion 31c has a curved surface, the curved surface may have a height that is, for example, one-fifth or more of the height of protrusion 31b.

[0045] Furthermore, a flow path 40 through which an oxygen-containing gas flows is formed in the space formed between the flat portion 31a and the element portion 3. The oxygen-containing gas flows from the first end 41 side toward the second end 42 side shown in Fig. 1C so as to avoid the plurality of protrusions 31b. That is, in the flow path 40 through which the oxygen-containing gas as the first gas flows, the first end 41 side corresponds to a supply port through which the oxygen-containing gas is supplied, and the second end 42 side corresponds to a discharge port through which the oxygen-containing gas is discharged.

[0046] The width d of the flow path 40 located between the flat portion 31a and the element unit 3 can be, for example, 0.1 mm to 10 mm, or even 0.3 mm to 3.5 mm. Furthermore, in the region of the first portion 311 having the convex portions 31b in a planar view, the area ratio of the convex portions 31b can be, for example, 1% to 60%, or even 3% to 45%. By setting the area ratio of the convex portions 31b to 1% or more, the flat portion 31a is less likely to come into contact with the element unit 3, making it easier to maintain the structure of the flow path 40. By setting the area ratio of the convex portions 31b to 60% or less, it becomes easier to circulate the oxygen-containing gas from the supply port to the discharge port without stagnation, making it easier to supply the oxygen-containing gas necessary for power generation to the air electrode 8 of the element unit 3. The region of the first portion 311 having the convex portions 31b is, for example, a region R1 shown in FIG. 1C , which includes multiple convex portions 31b within the region and whose outline is in contact with the convex portion 31b located at the outermost periphery. The shape of the region having the convex portions 31b may be, for example, a shape in which the perimeter of a polygon formed by connecting the outlines of all the convex portions 31b located within the region is minimized. By arranging such a flow path member 30, the power generation performance of the cell 1 is further improved. Note that the multiple convex portions 31b may have convex portions 31b whose tops 31c are spaced apart from the element portion 3.

[0047] 2A , the plurality of protrusions 31b include two or more first protrusions 31b1. The first protrusions 31b1 have a first length L1 in a first direction along the flat portion 31a. Here, the first direction is the longitudinal direction of the first protrusions 31b1 when viewed in a plan view from the Y-axis direction. The first length L1 is the maximum longitudinal dimension of the first protrusions 31b1 when viewed in a plan view from the Y-axis direction.

[0048] Furthermore, two or more first protrusions 31b1 are positioned side by side in the first direction. This allows the oxygen-containing gas flowing through the flow path 40 to branch between adjacent first protrusions 31b1 and easily flow in multiple directions. Therefore, compared to a case where the flow path member 30 has first protrusions 31b1 that are continuous in the first direction, the temperature uniformity of the element unit 3 via the flow path member 30 can be improved, and the power generation performance of the cell 1 can be improved.

[0049] 2A, two or more first protrusions 31b1 positioned side by side in the first direction are arranged so as to be positioned on a straight line extending in the first direction, but this is not limited to this. For example, when two or more first protrusions 31b1 are positioned on two or more straight lines extending parallel to each other along the first direction, they are also defined as being positioned side by side in the first direction.

[0050] The first protrusions 31b1 have a second length L2 in a second direction perpendicular to the first direction. The second direction of the first protrusions 31b1 may coincide with or differ from the short-side direction of the first protrusions 31b1 when viewed in a plan view from the Y-axis direction. The distance between adjacent first protrusions 31b1 in the first direction is defined as L3.

[0051] When the length of the first convex portion 31b1 in the first direction is defined as a first length L1 and the length of the first convex portion 31b1 in the second direction is defined as a second length L2, L1 and L2 may satisfy L1≧1.1×L2. This can increase the rigidity of the flow path member 30. Table 1 shows the results of comparing the ease of deformation of the flow path member 30 when L1 and L2 are changed for the first convex portion 31b1 shown in FIG. 2A . Note that Table 1 shows the results of evaluating the ease of deformation of the flow path member 30 on a three-point scale. Specifically, a circle indicates that no deformation of the flow path member 30 is observed and the flow path member 30 is particularly good; a triangle indicates that deformation of the flow path member 30 is observed but no defects in actual use are confirmed; and an x ​​indicates that deformation of the flow path member 30 is significant and may cause defects in actual use.

[0052]

[0053] As shown in Table 1, when L1 was 1.1 times or more than L2 (L1 / L2≧1.1), the deformation of the flow path member 30 was small, and there was no problem with the joint between the flow path member 30 and the support member 2. When L1 was 1.05 times L2 (L1 / L2=1.05), there was no problem with the joint between the flow path member 30 and the support member 2, but the deformation of the flow path member 30 was greater than when L1 was 1.1 times or more than L2, and the electrical resistance of the part in which the flow path member 30 and the support member 2 were joined increased. On the other hand, when L1 was the same as L2 (L1 / L2=1), the deformation of the flow path member 30 was even greater, and a joint failure with the support member 2 occurred.

[0054] When the shorter of the length in the X-axis direction and the length in the Y-axis direction of the entire region having the convex portion 31 b of the first portion 311 of the flow path member 30 is defined as L0, L1 and L0 may satisfy the relationship L1≦L0. This allows the oxygen-containing gas to flow from the supply port to the discharge port without stagnation.

[0055] When the direction from the supply port to the exhaust port of the oxygen-containing gas, i.e., the direction from the negative Z-axis side to the positive Z-axis side, is defined as the third direction, the first convex portion 31b1 may be arranged so that the first and second directions are different from the third direction. For example, the first convex portion 31b1 may be arranged so that the angle between the first direction and the third direction is 30° or more and 60° or less. This improves the rigidity of the flow path member 30 and further improves the performance of the cell 1.

[0056] The plurality of protrusions 31b may also include second protrusions 31b2 whose first and second directions are different from those of the first protrusions 31b1. This further improves the rigidity of the flow path member 30 and the thermal uniformity of the element section 3 via the flow path member 30, thereby further improving the performance of the cell 1.

[0057] The first direction of the second convex portion 31b2 may or may not coincide with the second direction of the first convex portion 31b1. The second direction of the second convex portion 31b2 may or may not coincide with the first direction of the first convex portion 31b1. Furthermore, the maximum dimension of the second convex portion 31b2 along the first direction when viewed in a plan view from the Y axis direction may or may not coincide with the first length L1 of the first convex portion 31b1. The maximum dimension of the second convex portion 31b2 along the second direction when viewed in a plan view from the Y axis direction may or may not coincide with the second length L2 of the first convex portion 31b1.

[0058] Furthermore, two or more second protrusions 31b2 may be arranged side by side in the first direction of the second protrusions 31b2. Furthermore, the second protrusions 31b2 may be arranged between the first protrusions 31b1 arranged side by side in the first direction. This further improves the thermal uniformity of the element section 3 via the flow path member 30, and further improves the power generation performance of the cell 1.

[0059] <Configuration of Electrochemical Cell Device> Next, an electrochemical cell device according to this embodiment using the above-described electrochemical cell 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 an embodiment. Figure 3B is a cross-sectional view taken along line XX shown in Figure 3A. Figure 3C is a top view showing an example of an electrochemical cell device according to an embodiment.

[0060] As shown in FIG. 3A, the cell stack device 10 includes a cell stack 11 having a plurality of cells 1 arranged (stacked) in the thickness direction (Y-axis direction) of the cells 1, and a fixing member 12.

[0061] 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.

[0062] 3B, 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.

[0063] 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.

[0064] In the example shown in Fig. 3A, fuel gas is stored in an internal space 22 (see Fig. 3B) 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 flow path 2a (see Fig. 1A) inside the cell 1. The fuel gas supplied to the gas tank 16 is generated in a reformer 104 (see Fig. 4), which will be described later.

[0065] 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.

[0066] 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 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.

[0067] 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 1, i.e., the thickness direction T, 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 1 in the width direction (X-axis direction: see FIG. 1A ).

[0068] 3B, the joints between the inner walls of the insertion holes 15a and the lower ends of the cells 1 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 1, respectively, and also bonds and fixes the lower ends of the cells 1 to each other. The flow paths 2a of each cell 1 communicate with the internal space 22 of the support member 14 at their lower ends.

[0069] A material with low electrical 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.

[0070] 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.

[0071] 3B , a conductive member 18 is interposed between adjacent cells 1 among the plurality of cells 1. The conductive member 18 electrically connects one adjacent cell 1 to the other adjacent cell 1 in series. More specifically, the conductive member 18 connects the fuel electrode 5 of one cell 1 to the air electrode 8 of the other cell 1.

[0072] 3B, 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 conductive portion 19 that protrudes outside the cell stack 11. The conductive portion 19 collects electricity generated by power generation in the cells 1 and extracts it to the outside. Note that the end current collecting member 17 is not shown in FIG. 3A.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] <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 an 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.

[0077] 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.

[0078] 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.

[0079] The fuel gas produced in the reformer 102 is supplied to the flow path 2 a of the cell 1 (see FIG. 1A) through the gas distribution pipe 20 , the gas tank 16 , and the support member 14 .

[0080] 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.

[0081] 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.

[0082] <Module Enclosure Device> Fig. 5 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. 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 6A to 6C are plan views showing examples of first protrusions of a flow path member. Note that, to simplify the illustration, each of FIGS. 6A to 6C illustrates two first protrusions 31b1 arranged side by side such that the first direction is along the X-axis.

[0087] As shown in Figures 6A to 6C, the first convex portions 31b1, when viewed in plan from the Y-axis direction, may be elliptical (see Figure 6A), rectangular (see Figure 6B), or oval with semicircles joined to both ends of a rectangle (see Figure 6C). Furthermore, the distance L3 between adjacent first convex portions 31b1 in the first direction may be equal to or greater than the second length L2. The distance L3 may be, for example, 0.1 mm or greater. The distance L3 may be any distance that allows the oxygen-containing gas to flow smoothly from the supply port to the discharge port. Note that the second convex portions 31b2 are not shown in Figures 6A to 6C.

[0088] 6A to 6C may be applied to the second protrusion 31b2 (see FIG. 2A). In such a case, the shapes of the first protrusion 31b1 and the second protrusion 31b2 may be the same or different.

[0089] <Shape of third convex portion> The plurality of convex portions 31b may have convex portions 31b whose shapes in plan view from the Y-axis direction are different from those of the first convex portion 31b1 and the second convex portion 31b2. Figures 7A to 7C are plan views showing examples of third convex portions included in the flow path member.

[0090] 7A , the plurality of protrusions 31b may include, as third protrusions 31ba, protrusions 31b3 that are Λ-shaped (V-shaped) when viewed in a plane from the Y-axis direction. The plurality of protrusions 31b may also include protrusions 31b4 that are Y-shaped when viewed in a plane from the Y-axis direction. The plurality of protrusions 31b may also include protrusions 31b5 that are X-shaped when viewed in a plane from the Y-axis direction.

[0091] The plurality of protrusions 31b may also have a polygonal shape when viewed in a plan view from the Y-axis direction. For example, as shown in FIG. 7B , the plurality of protrusions 31b may have a protrusion 31b6 that has a triangular shape when viewed in a plan view from the Y-axis direction. The plurality of protrusions 31b may also have a protrusion 31b7 that has a square shape when viewed in a plan view from the Y-axis direction. Note that each side of the polygon may be a straight line or may include a curve. The protrusions 31b6 and 31b7 may also have a recess 31d in their central portions. The depth of the recess 31d may be the same as or different from the width d (see FIG. 2B ) of the flow channel 40 located between the flat portion 31a and the element portion 3.

[0092] 7C, the plurality of protrusions 31b may include a protrusion 31b8 having a circular shape when viewed from above in the Y-axis direction, or a trapezoidal protrusion 31b9. The protrusions 31b8 and 31b9 may each have a recess 31d in the center. The depth of the recess 31d may be the same as or different from the width d (see FIG. 2B) of the flow channel 40 located between the flat portion 31a and the element portion 3.

[0093] The plurality of protrusions 31b may include one or more of the protrusions 31b3 to 31b9 described above. Note that the shapes of the protrusions 31b3 to 31b9 shown in Figures 7A to 7C are merely examples, and they may have a shape rotated around the Y axis, for example.

[0094] The above describes an example in which the flow path member 30 has a plurality of protrusions 31b protruding toward the air electrode 8 of the element section 3, but the plurality of protrusions 31b may also protrude toward the support member 2. Furthermore, for example, a flow path member 30 having a plurality of protrusions 31b protruding toward the air electrode 8 and / or the fuel electrode 5 may be used as an interconnector for a flat plate-type cell that does not have a support member 2.

[0095] 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 hydrogen electrode as a first electrode and an oxygen electrode as 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.

[0096] 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.

[0097] In one embodiment, (1) an electrochemical cell includes an element portion; and a flow path member having a first flat portion facing the element portion and a plurality of convex portions protruding from the first flat portion toward the element portion, wherein the plurality of convex portions have a first length in a first direction along the first flat portion and include two or more first convex portions aligned in the first direction.

[0098] (2) In the electrochemical cell of (1) above, when the length of the first convex portion in the first direction is defined as a first length L1 and the length of the first convex portion in a second direction perpendicular to the first direction is defined as a second length L2, L1 and L2 may satisfy L1≧1.1×L2.

[0099] (3) In the electrochemical cell of (1) or (2) above, the flow path member has a supply port through which a first gas is supplied and a discharge port through which the first gas is discharged, and when a direction from the supply port toward the discharge port is defined as a third direction, the first direction and a second direction perpendicular to the first direction may be different from the third direction.

[0100] (4) In the electrochemical cell of (3) above, the angle between the first direction and the third direction may be equal to or greater than 30° and equal to or less than 60°.

[0101] (5) In the electrochemical cell of any one of (1) to (4) above, the first convex portion may have a second flat portion at the top portion facing the element portion.

[0102] In one embodiment, (6) the electrochemical cell device has a cell stack including any one of the electrochemical cells (1) to (5) above.

[0103] In one embodiment, (7) a module includes the electrochemical cell device of (6) above, and a container that houses the electrochemical cell device.

[0104] 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.

[0105] 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.

[0106] REFERENCE SIGNS LIST 1 cell 2 support member 3 element portion 5 fuel electrode 6 solid electrolyte layer 8 air electrode 10 cell stack device 30 flow path member 31a flat portion 31b protruding portion 100 module 110 module receiving device

Claims

1. The element part, A flow channel member having a first flat portion facing the element portion and a plurality of protrusions projecting from the first flat portion toward the element portion. Equipped with, The plurality of protrusions have a first length in a first direction along the first flat portion and include two or more first protrusions aligned in the first direction. Electrochemical cell.

2. When the length of the first protrusion in the first direction is defined as the first length L1 and the length in the second direction perpendicular to the first direction is defined as the second length L2, L1 and L2 satisfy L1 ≥ 1.1 × L2. The electrochemical cell according to claim 1.

3. The flow channel member has a supply port into which the first gas is supplied and a discharge port into which the first gas is discharged. When the direction from the supply port to the discharge port is defined as the third direction, the first direction and the second direction perpendicular to the first direction are different from the third direction. The electrochemical cell according to claim 1.

4. The angle between the first direction and the third direction is between 30° and 60°. The electrochemical cell according to claim 3.

5. The first protrusion has a second flat portion at its apex facing the element portion. The electrochemical cell according to claim 1.

6. A cell stack comprising an electrochemical cell according to any one of claims 1 to 5 Electrochemical cell apparatus.

7. The electrochemical cell apparatus according to claim 6, A storage container for housing the electrochemical cell apparatus and A module equipped with the following features.

8. The module according to claim 7, Auxiliary equipment for operating the aforementioned module, An outer case housing the module and the auxiliary equipment A module housing device equipped with the following features.