Net, water electrolysis device, and fuel cell

Abstract

The net is configured from a skeleton having a plurality of pillar sections and a plurality of node sections. Each of the plurality of node portions connects two or more of the plurality of pillar portions. The skeleton is formed by a skeleton main body and an interior surrounded by the skeleton main body. The skeleton body is substantially formed of nickel or a nickel alloy.

Description

Technical Field

[0001] The present invention relates to a net, a water electrolysis device, and a fuel cell. This application claims priority to Japanese patent application No. 2023-139548 filed on August 30, 2023. All the contents described in the Japanese patent application are cited in this specification by reference. Background Art

[0002] Conventionally, metal meshes have been used in electronic devices, water electrolysis electrodes, and the like (Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2009-185378. Summary of the invention

[0006] A net in one embodiment of the present invention is composed of a skeleton having a plurality of pillars and a plurality of node portions. The plurality of node portions respectively connect two or more of the plurality of pillars. The skeleton is formed by a skeleton body and an interior surrounded by the skeleton body. The skeleton body is substantially formed of nickel or a nickel alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a top view of the net according to embodiment 1.

[0008] Figure 2 is from Figure 1 An end view of the support portion of the net of Embodiment 1 as viewed in the direction of the arrows along line II-II in FIG.

[0009] Figure 3 is from Figure 1 An end view of a node portion of the mesh of Embodiment 1 as viewed in the direction of arrows along line III-III in FIG.

[0010] Figure 4 This is a diagram showing a flow chart of the net manufacturing method according to the first embodiment.

[0011] Figure 5 This is a top view of the net according to the second embodiment.

[0012] Figure 6 is from Figure 5 An end view of the mesh of Embodiment 2 observed in the direction of the arrows on line VI-VI.

[0013] Figure 7 This is a diagram showing a flow chart of a method for producing a net according to the second embodiment.

[0014] Figure 8 This is a plan view of a net according to a first modified example of the second embodiment.

[0015] Fig. 9 This is a plan view of a net according to a second modified example of the second embodiment.

[0016] Fig.10 This is a plan view of a net according to a third modified example of the second embodiment.

[0017] Fig.11 This is a plan view of a net according to a fourth modified example of the second embodiment.

[0018] Fig.12 This is a plan view of a net according to a fifth modification of the second embodiment.

[0019] Fig.13 This is a schematic partial cross-sectional view of a water electrolysis device according to a third embodiment.

[0020] Fig.14 This is a schematic partial cross-sectional view of a fuel cell according to a fourth embodiment.

[0021] Fig.15 This is a schematic partial cross-sectional view of a cell unit of a fuel cell according to a fourth embodiment. DETAILED DESCRIPTION

[0022] [Problems to be Solved by the Invention]

[0023] In recent years, metal meshes have been used as water electrolysis electrodes. Metal meshes are required to have excellent mechanical strength and low resistance. However, in a mesh formed by weaving wires of wire-drawn metal, the warp (metal wire) and the weft (metal wire) are in contact with each other only at the positions where they cross. Therefore, it is difficult for such a mesh to achieve excellent mechanical strength and low resistance.

[0024] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a mesh having better mechanical strength and lower electrical resistance.

[0025] [Effects of the Invention]

[0026] According to the present invention, a mesh having more excellent mechanical strength and lower electrical resistance can be provided.

[0027] [Overview of Embodiments of the Invention]

[0028] First, embodiments of the present invention will be listed and described.

[0029] [1] A net according to one embodiment of the present invention is composed of a skeleton having a plurality of pillars and a plurality of node portions. The plurality of node portions respectively connect two or more of the plurality of pillars. The skeleton is formed by a skeleton body and an interior surrounded by the skeleton body. The skeleton body is substantially formed of nickel or a nickel alloy.

[0030] In the mesh of the present invention, two or more support parts are integrated at the node part, so that the mesh has a more excellent mechanical strength and a lower electrical resistance.

[0031] [2] In the above [1], in the cross section at the center of each of the plurality of node portions along the length direction of one of the two or more support portions, a first ratio of the short diameter of the interior to the long diameter of the interior may be greater than 0.01 and less than 0.9. In the cross section at the center of the one support portion perpendicular to the length direction, a second ratio of the second length of the interior to the first length of the interior may be greater than 0.1 and less than 1.0. The first length is the length of the interior in the in-plane direction of the net in the cross section at the center of the one support portion. The second length is the length of the interior in the thickness direction of the net in the cross section at the center of the one support portion.

[0032] Therefore, the surface irregularities of the mesh are reduced, and the mesh prevents the member disposed adjacent to the mesh from being pierced. When the member is an insulating member such as a diaphragm of a zero-gap water electrolysis cell, the insulating properties of the insulating member can be ensured.

[0033] [3] In the above [1] or [2], the content of the first atom in the above skeleton body can be greater than 0 ppm and less than 100 ppm on a mass basis, and the above first atom can be at least one atom selected from a phosphorus atom and a boron atom.

[0034] The melting point of nickel or nickel alloy is lowered due to the reducing agent component inevitably mixed in when the first atom is reduced. Therefore, the mesh has more excellent mechanical strength and lower electrical resistance.

[0035] [4] In any of the above [1] to [3], the interior may be hollow.

[0036] Therefore, a net having better mechanical strength, lower electrical resistance and lighter weight can be provided. In addition, by rolling the net, the thickness of the net can be easily adjusted. The net can be easily made to fit closely to a component adjacent to the net (for example, a diaphragm of a water electrolysis cell, etc.).

[0037] [5] In any one of the above [1] to [3], the inside may be formed of an alkali-resistant resin or an alkali-resistant carbon fiber.

[0038] Therefore, the mesh has more excellent alkali resistance. Since the inside of the skeleton is solid, the mesh has more excellent mechanical strength. The mesh can be suitably used for a water electrolysis electrode of a water electrolysis device using a strong alkaline solution.

[0039] [6] In the above [5], the alkali-resistant resin may be at least one resin selected from the group consisting of polypropylene, polyethylene, polyester, nylon and polytetrafluoroethylene.

[0040] Therefore, the mesh has more excellent alkali resistance. Since the inside of the skeleton is solid, the mesh has more excellent mechanical strength. The mesh can be suitably used for a water electrolysis electrode of a water electrolysis device using a strong alkaline solution.

[0041] [7] In any of the above [1] to [6], the opening ratio of the above mesh may be greater than 0.2% and less than 80%.

[0042] Since the mesh has an opening rate of 0.2% or more, the mesh can pass liquid and gas. The mesh can be suitably used as a water electrolysis electrode of a water electrolysis device using a strong alkaline solution. In addition, since the mesh has an opening rate of 80% or less, the mesh has more excellent mechanical strength.

[0043] [8] In any of the above [1] to [7], the average equivalent circular diameter of each of the plurality of support portions in a cross section perpendicular to the length direction of each of the plurality of support portions can be greater than or equal to 0.007 mm and less than or equal to 0.5 mm.

[0044] Therefore, the web has more excellent mechanical strength.

[0045] [9] In any one of [1] to [8] above, the mesh has a main surface with grooves formed thereon. The depth of the grooves may be at least 10% of the thickness of the mesh. When the main surface is viewed from above, the area of ​​the grooves may be at least 10% of the area of ​​the main surface.

[0046] Therefore, the uniformity of the flow of fluids such as gas and liquid in the net can be improved.

[0047]

[10] In the above [9], when viewed from above, the net has a first edge, a second edge opposite to the first edge, a third edge, and a fourth edge opposite to the third edge. The third edge and the fourth edge are connected to the first edge and the second edge, respectively. When viewed from above, the skeleton may have a lattice shape. The plurality of linear bodies constituting the lattice may extend from one of the first edge, the second edge, the third edge and the fourth edge to another of the first edge, the second edge, the third edge and the fourth edge, respectively. The minimum value of the ratio of the length of the portion of each of the plurality of linear bodies that does not form the groove may be greater than 10%.

[0048] Therefore, the uniformity of the flow of fluids such as gas and liquid in the net can be improved.

[0049]

[11] A water electrolysis device according to one embodiment of the present invention comprises a current collector, a diaphragm, and an electrode disposed between the current collector and the diaphragm. At least one of the electrode and the current collector is formed by the mesh according to any one of [1] to

[10] .

[0050] Therefore, the uniformity of the flow of the aqueous solution in at least one of the electrode and the current collector can be improved. In addition, the discharge of the gas generated in the water electrolysis device is promoted, and the performance of the water electrolysis device can be improved.

[0051]

[12] A fuel cell according to one embodiment of the present invention comprises a current collector, an electrolyte, and an electrode disposed between the current collector and the electrolyte. The current collector is formed of the mesh according to any one of [1] to

[10] .

[0052] Therefore, the uniformity of the flow of gas in the current collector can be improved, and the performance of the fuel cell can be improved.

[0053] [Details of the embodiments of the present invention]

[0054] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings of the present invention, the same reference numerals represent the same parts or equivalent parts. In addition, the dimensional relationships such as length, width, thickness, depth, etc. are appropriately changed for the clarity and simplification of the accompanying drawings and do not necessarily represent the actual dimensional relationships.

[0055] (Implementation Method 1)

[0056] refer to Figure 1~Figure 3 , network 1 of implementation mode 1 is described. Figure 1 It is a top view of the net 1. Figure 2 is from Figure 1 End view observed in the direction of the arrow on line II-II. Figure 3 is from Figure 1 End view observed in the direction of the arrow on line III-III.

[0057] The net 1 is composed of a skeleton 5 having a plurality of pillars 6 and a plurality of nodes 7. The plurality of nodes 7 respectively connect two or more of the plurality of pillars 6. The skeleton 5 is formed of a skeleton body 2 and an interior 3 surrounded by the skeleton body 2. The skeleton body 2 is substantially formed of nickel or a nickel alloy.

[0058] Therefore, the mesh 1 has excellent mechanical strength and low resistance. The reason for this is presumably that the skeleton 5 of the mesh 1 has a structure in which a plurality of hollow metal wires are connected by metal bonding at each of a plurality of node portions 7, rather than a structure in which metal wires are in contact with each other at positions where they intersect.

[0059] ≪Network 1≫

[0060] <Structure of Net 1>

[0061] The net 1 of the present embodiment is composed of a skeleton 5 having a plurality of pillars 6 and a plurality of nodes 7. The plurality of nodes 7 respectively connect two or more pillars 6 among the plurality of pillars 6. The plurality of nodes 7 may respectively connect three or more pillars 6 among the plurality of pillars 6. The plurality of nodes 7 may respectively connect seven or less pillars 6 among the plurality of pillars 6, six or less pillars 6 among the plurality of pillars 6, five or less pillars 6 among the plurality of pillars 6, or four or less pillars 6 among the plurality of pillars 6. The plurality of nodes 7 may respectively connect two or more and seven or less pillars 6 among the plurality of pillars 6, three or more and six or less pillars 6 among the plurality of pillars 6, three or more and five or less pillars 6 among the plurality of pillars 6, or three or more and four or less pillars 6 among the plurality of pillars 6. The plurality of nodes 7 may respectively connect three pillars 6, four pillars 6, five pillars 6, six pillars 6, or seven pillars 6. In the present invention, the net 1 refers to a mesh-like structure. The mesh-like structure is also referred to as a net structure.

[0062] The average equivalent circular diameter of each of the multiple pillars 6 in the cross section perpendicular to the length direction of each of the multiple pillars 6 can be more than 0.007mm and less than 0.5mm. Thus, the net 1 has more excellent mechanical strength. The lower limit of the average equivalent circular diameter of each of the multiple pillars 6 can be more than 0.007mm, can be more than 0.01mm, can be more than 0.1mm. The upper limit of the average equivalent circular diameter of each of the multiple pillars 6 can be less than 0.5mm, can be less than 0.3mm, can be less than 0.2mm. The average equivalent circular diameter of each of the multiple pillars 6 can be more than 0.01mm and less than 0.3mm, can be more than 0.1mm and less than 0.2mm.

[0063] The average equivalent circular diameter of the pillar portion 6 in the cross section perpendicular to the length direction of the pillar portion 6 can be determined by the following method. Use a cross-section polisher (CP) to expose the cross section of the pillar portion 6 perpendicular to the length direction of the pillar portion 6. Then, observe the cross section of the pillar portion 6 with a scanning electron microscope (SEM). Finally, calculate the average value of the equivalent circular diameters of any 10 pillar portions 6 in the cross section of the pillar portion 6. In this way, the average equivalent circular diameter of the pillar portion 6 can be determined.

[0064] The opening ratio of the net 1 can be more than 0.2% and less than 80%. Since the opening ratio of the net 1 is more than 0.2%, the fluid easily passes through the net 1, and the net 1 becomes lighter. Since the opening ratio of the net 1 is less than 80%, the net 1 has more excellent mechanical strength and lower resistance. The lower limit of the opening ratio of the net 1 can be more than 0.2%, can be more than 6%, can be more than 10%, can be more than 20%, can be more than 25%, can be more than 40%. The upper limit of the opening ratio of the net 1 can be less than 80%, can be less than 70%, can be less than 60%. The opening ratio of the net 1 can be more than 0.2% and less than 70%, can be more than 60% and less than 80%, can be more than 6% and less than 70%, can be more than 10% and less than 70%, can be more than 20% and less than 70%, can be more than 40% and less than 60%.

[0065] The opening ratio of the net 1 can be measured by using an opening ratio measuring device disclosed in Japanese Patent Application Laid-Open No. 2005-290623.

[0066] refer to Figure 3 , the thickness T of the mesh 1 is the maximum thickness of the node portion 7. The thickness T of the mesh 1 can be greater than 0.05 mm and less than 0.5 mm. Thus, the mechanical strength of the mesh 1 can be further improved. The lower limit of the thickness T of the mesh 1 can be greater than 0.05 mm, can be greater than 0.1 mm, can be greater than 0.2 mm. The upper limit of the thickness T of the mesh 1 can be less than 0.5 mm, can be less than 0.4 mm, can be less than 0.3 mm. The thickness T of the mesh 1 can be greater than 0.1 mm and less than 0.4 mm, can be greater than 0.2 mm and less than 0.3 mm.

[0067] The thickness T of the web 1 can be determined by the following method. First, the thickness of the node portions 7 at any 10 locations in the web 1 is measured using a digital thickness gauge (TECLOCK Co., Ltd.). Then, the average value of the thickness of the 10 node portions 7 is calculated. In this way, the thickness T of the web 1 is determined.

[0068] The shape of the openings 4 of the net 1 is not particularly limited, and can be, for example, a quadrilateral, a hexagon, an ellipse, or a triangle. The quadrilateral can be, for example, a square, a rectangle, or a rhombus.

[0069] In the skeleton 5, the mass per unit area can be 10g / m 2 Above and 1000g / m 2 Therefore, the wire is not easily broken (in other words, the skeleton 5 is not easily broken), the net 1 is easy to bend, and thus it is easy to manufacture using a continuous equipment for plating and heat treatment, and the net 1 can be made lighter. In addition, the lower limit of the mass per unit area can be 50 g / m 2 Above, can be 100g / m2 Above, can be 200g / m 2 The upper limit of the mass per unit area can be 800 g / m 2 Below, can be 500g / m 2 Below, can be 400g / m 2 The mass per unit area can be determined by the Archimedean method.

[0070] The skeleton 5 is formed by the skeleton body 2 and the interior 3 surrounded by the skeleton body 2. Thereby, especially when used as a water electrolysis electrode, the mechanical strength of the mesh 1 can be improved, the electrical resistance of the mesh 1 can be suppressed to a low level, and the mesh 1 can be made lightweight. In addition, "the skeleton 5 is formed by the skeleton body 2 and the interior 3 surrounded by the skeleton body 2" can also be understood as "in the skeleton 5, the composition of the skeleton body 2 is different from the composition of the interior 3 surrounded by the skeleton body 2". In addition, the concept of "the skeleton 5 is formed by the skeleton body 2 and the interior 3 surrounded by the skeleton body 2" also includes, for example, a case where the skeleton 5 has an end face, and the interior 3 is exposed to the outside of the mesh 1 at the end face of the skeleton 5.

[0071] "The skeleton 5 is formed by the skeleton main body 2 and the interior 3 surrounded by the skeleton main body 2" can be determined by the following method. By observing a cross section perpendicular to the length direction of the support portion 6 at any point of the skeleton 5, it is confirmed at the cross section that "the skeleton 5 is formed by the skeleton main body 2 and the interior 3 surrounded by the skeleton main body 2". Then, for any other four places of the skeleton 5, it is similarly confirmed that "the skeleton 5 is formed by the skeleton main body 2 and the interior 3 surrounded by the skeleton main body 2". In the above way, it is determined that "the skeleton 5 is formed by the skeleton main body 2 and the interior 3 surrounded by the skeleton main body 2" in the mesh 1.

[0072] <Frame body>

[0073] The skeleton body 2 is substantially formed of nickel or a nickel alloy. Therefore, the mechanical strength of the mesh 1 can be improved, and the electrical resistance of the mesh 1 can be suppressed to be low. Here, "the skeleton body 2 is substantially formed of nickel or a nickel alloy" means that the skeleton body 2 may contain other components besides nickel within the range that does not impair the effect of the present invention. As other components, for example, the first atom described later, cobalt, chromium, tin, copper and iron can be cited. In addition, in the present embodiment, nickel means a nickel atom. The nickel alloy can be at least one alloy selected from NiCo alloy, NiCr alloy, NiSn alloy, NiCu alloy and NiFe alloy.

[0074] The first atom is inevitably contained in the plating solution used in the plating step (S3) described later. The first atom is introduced into the skeleton body 2 in the plating step (S3). The first atom is, for example, at least one atom selected from a phosphorus atom and a boron atom.

[0075] The content of the first atom in the skeleton body 2 can be greater than 0 ppm and less than 100 ppm on a mass basis. Since nickel and the first atom form a eutectic, the melting point of the skeleton body 2 is lower than that of nickel. Therefore, in the heat treatment process (S4) described later, the mesh 1 becomes softer and the plating defects of the skeleton body 2 are repaired. The mesh 1 has better mechanical strength and lower resistance. The lower limit of the content of the first atom in the skeleton body 2 can be greater than 0 ppm on a mass basis, can be greater than 5 ppm, and can be greater than 10 ppm. The upper limit of the content of the first atom in the skeleton body 2 can be less than 100 ppm on a mass basis, can be less than 50 ppm, and can be less than 30 ppm. The content of the first atom in the skeleton body 2 can be greater than 5 ppm and less than 50 ppm, and can be greater than 10 ppm and less than 30 ppm.

[0076] The composition of the skeleton body 2 can be measured by performing ICP atomic emission spectroscopy and mass spectrometry analysis after all metal components of the skeleton body 2 are dissolved.

[0077] <Interior>

[0078] The interior 3 may be hollow. Therefore, the metal content of the skeleton body 2 is suppressed to be relatively low, and the surface area of ​​the skeleton 5 becomes larger. It is possible to provide a mesh 1 having better mechanical strength and lower electrical resistance and being lighter. In addition, since the interior 3 is hollow, the mechanical strength of the mesh 1 in the direction along the diagonal of the quadrilateral is improved, especially when the shape of the opening 4 is a quadrilateral.

[0079] The fact that the interior 3 is hollow can be confirmed by the following method: Use CP to expose the cross section of the skeleton 5. Then, observe the cross section of the skeleton 5 with SEM. In this way, it can be confirmed that the interior 3 is hollow.

[0080] The inner part 3 can be formed of an alkali-resistant resin or an alkali-resistant carbon fiber. Therefore, the net 1 has a more excellent alkali resistance. Since the inner part 3 of the skeleton 5 is solid, the net 1 has a more excellent mechanical strength. The net 1 can be applied to a water electrolysis electrode of a water electrolysis device using a strong alkaline solution.

[0081] The alkali-resistant resin may be at least one selected from polypropylene, polyethylene, polyester, nylon and polytetrafluoroethylene. The inner portion 3 may also be formed of a material softer than the skeleton body 2. The inner portion 3 may be formed of a material having a smaller specific gravity than the skeleton body 2. Therefore, a metal (i.e., nickel or a nickel alloy) and a resin having a higher softness than the metal (nickel or a nickel alloy) form a composite material. The skeleton 5 is formed of a composite material. Therefore, a net 1 having a more excellent mechanical strength and a lower resistance and being lighter can be provided.

[0082] The alkali-resistant carbon fiber can be at least one carbon fiber selected from polyacrylonitrile (PAN) sintered carbon fiber and pitch-based carbon fiber. Thus, the metal (i.e., nickel or nickel alloy) and the carbon fiber having higher softness than the metal (nickel or nickel alloy) form a composite material. The skeleton 5 is formed of the composite material. Therefore, it is possible to provide a net 1 having better mechanical strength, lower resistance, and lighter weight.

[0083] Whether the inner part 3 is formed of an alkali-resistant resin or an alkali-resistant carbon fiber can be determined by the following method. First, the mass of the net 1 is measured (hereinafter, also recorded as the "first mass"). Next, the net 1 is immersed in a KOH solution of about 6 mol / L under the conditions of 70°C and 1 week. Next, the net 1 after the immersion is washed with water and then dried. Next, the mass of the dried net 1 is measured (hereinafter, also recorded as the "second mass"). Next, "[{(first mass)-(second mass)} / (first mass)]×100" is calculated. When "[{(first mass)-(second mass)} / (first mass)]×100" is less than 5%, it is determined that "the inner part 3 is formed of an alkali-resistant resin or an alkali-resistant carbon fiber".

[0084] The wire diameter of the alkali-resistant carbon fiber can be 0.05 mm or more and 0.5 mm or less. Therefore, a net 1 having better mechanical strength, lower resistance, and lighter weight can be provided. The lower limit of the wire diameter of the alkali-resistant carbon fiber can be 0.05 mm or more, and can be 0.07 mm or more. The upper limit of the wire diameter of the alkali-resistant carbon fiber can be 0.5 mm or less, can be 0.2 mm or less, and can be 0.1 mm or less. The wire diameter of the alkali-resistant carbon fiber can be 0.05 mm or more and 0.2 mm or less, and can be 0.07 mm or more and 0.1 mm or less.

[0085] The wire diameter of the alkali-resistant carbon fiber can be determined according to the test method of "carbon fiber single fiber diameter and cross-sectional area" of "JIS R7607:2000".

[0086] The density of alkali-resistant carbon fiber can be 1.7 g / cm 3 Above and 1.9g / cm 3 Therefore, a web 1 having a more excellent mechanical strength and a lower electrical resistance and being lighter can be provided. The lower limit of the density of the alkali-resistant carbon fiber may be 1.79 g / cm 3 Above, it can be 1.80g / cm 3 Above, it can be 1.81g / cm 3 The upper limit of the density of the alkali-resistant carbon fiber can be 1.9 g / cm 3 Below, can be 1.85g / cm3 Below, it can be 1.83g / cm 3 The density of alkali-resistant carbon fiber can be 1.79 g / cm 3 Above and 1.85g / cm 3 Below, it can be 1.81g / cm 3 Above 1.83g / cm 3 the following.

[0087] The density of the alkali-resistant carbon fiber can be determined according to the test method of "Carbon Fiber-Density" in "JIS R7603:1999".

[0088] <First ratio, second ratio>

[0089] refer to Figure 3 , in a cross section at the center of the node portion 7 along the length direction of one of the two or more pillar portions 6 connected by the plurality of node portions 7, a first ratio D2 / D1 of the short diameter D2 of the inner portion 3 to the long diameter D1 of the inner portion 3 may be 0.01 or more and 0.9 or less. The long diameter D1 of the inner portion 3 is the length of the inner portion 3 in the in-plane direction of the net 1 in the cross section at the center of the node portion 7 along the length direction of the one pillar portion 6. The short diameter D2 of the inner portion 3 is the length of the inner portion 3 in the thickness direction of the net 1 in the cross section at the center of the node portion 7 along the length direction of the one pillar portion 6.

[0090] refer to Figure 2 , in a cross section at the center of one of the two or more support parts 6 connected by the plurality of node parts 7 and perpendicular to the length direction of the support part 6, a second ratio D4 / D3 of the second length D4 of the inner part 3 to the first length D3 of the inner part 3 may be 0.1 or more and 1.0 or less. The first length D3 of the inner part 3 is the length of the inner part 3 in the in-plane direction of the net 1 in the cross section at the center of the one support part 6. The second length D4 of the inner part 3 is the length of the inner part 3 in the thickness direction of the net 1 in the cross section at the center of the one support part 6.

[0091] Thus, the surface unevenness of the net 1 is reduced. It is prevented that the member arranged adjacent to the net 1 is damaged by the net 1. In the case where the member is an insulating member such as a diaphragm of a zero-gap water electrolysis cell, the insulation of the insulating member can be ensured. In addition, when the interior 3 is hollow, while the surface area of ​​the net 1 is kept large, it is not easy to cause damage to the node portion 7. Therefore, it is possible to provide a net 1 with better mechanical strength, lower resistance, and lighter weight.

[0092] The lower limit of the first ratio D2 / D1 may be greater than 0.01, greater than 0.05, or greater than 0.1. The upper limit of the first ratio D2 / D1 may be less than 0.9, less than 0.5, or less than 0.4. The first ratio D2 / D1 may be greater than 0.05 and less than 0.5, or greater than 0.1 and less than 0.4.

[0093] The first ratio D2 / D1 can be determined by the following method. Using CP, a cross section at the center of the node 7 along the length direction of one of the two or more pillars 6 connected by a plurality of node portions 7 is exposed. Then, the cross section at the center of the node 7 is observed using a SEM. The average value of the first ratio D2 / D1 at any 10 points in the cross section at the center of the node 7 is calculated. In this way, the first ratio D2 / D1 can be determined.

[0094] The lower limit of the second ratio D4 / D3 may be greater than 0.1, greater than 0.2, or greater than 0.4. The upper limit of the second ratio D4 / D3 may be less than 1.0, less than 0.8, or less than 0.5. The second ratio D4 / D3 may be greater than 0.2 and less than 0.8, or greater than 0.4 and less than 0.5.

[0095] The second ratio D4 / D3 can be determined by the following method. Using CP, a cross section at the center of the pillar portion 6 perpendicular to the length direction of one of the two or more pillar portions 6 connected by a plurality of node portions 7 is exposed. Then, the cross section at the center of the pillar portion 6 is observed using an SEM. The average value of the second ratio D4 / D3 at any 10 points in the cross section at the center of the pillar portion 6 is calculated. In this way, the second ratio D4 / D3 can be determined.

[0096] <Application>

[0097] The net 1 of the present embodiment can be used as a water electrolysis electrode. In addition, the net 1 of the present embodiment can also be applied to, for example, a solid oxide fuel cell, a solid oxide steam electrolysis cell, a water electrolysis cell, or an electromagnetic wave shielding member. In addition, as a water electrolysis cell, an alkaline water electrolysis cell and an anion exchange membrane water electrolysis cell can be exemplified.

[0098] [Method for manufacturing net 1]

[0099] refer to Figure 4 , a method for manufacturing the net 1 of this embodiment will be described.

[0100] The method for manufacturing the net 1 of the present embodiment includes, for example, a process of preparing a blank (step S1), a process of obtaining a net intermediate (step S2), and a process of plating the surface of the net intermediate (step S3). In addition, the method for manufacturing the net 1 of the present embodiment may further include a heat treatment process (step S4) after the plating process (step S3). The method for manufacturing the net 1 of the present embodiment may also include a calendering process (step S5).

[0101] Step S1

[0102] In step S1, a blank is prepared. The blank may be prepared by purchasing a commercial product or by manufacturing using a conventionally known method.

[0103] The weaving method of the blank can be a weaving method selected from plain weave, twill weave, satin weave, plain Dutch weave, herringbone weave, twilled Dutch weave, honeycomb weave, 3D fabric weave, etc. The wire diameter of the blank is not particularly limited, and can be, for example, 0.007 mm or more and 2 mm or less. The mesh of the blank is not particularly limited, and can be, for example, 0.004 mm or more and 1 mm or less. The spacing of the blank is not particularly limited, and can be, for example, 0.007 mm or more and 3 mm or less.

[0104] The blank may also be formed of the above-mentioned alkali-resistant resin or alkali-resistant carbon fiber. Carbon fiber has conductivity. Therefore, when the blank is formed of alkali-resistant carbon fiber, step S2 described later can be omitted.

[0105] Step S2

[0106] In step S2, a conductive coating layer is formed on the surface of the blank. For example, a conductive slurry is applied to the surface of the blank. Then, the solvent is volatilized from the conductive slurry. In this way, a mesh intermediate is obtained. In the conductive slurry, the conductive carbon particles can be more than 3 parts by mass and less than 50 parts by mass relative to 100 parts by mass of the solvent. As the solvent, water, etc., for example, can be mentioned. As the conductive carbon particles, natural graphite, artificial graphite, etc., for example, can be mentioned. In the present invention, "conductivity" means "electrical conductivity".

[0107] Step S3

[0108] In step S3, the surface of the mesh intermediate is plated, such as by nickel plating. Plating can be performed by a conventionally known method. In addition, when nickel plating, Ni and Co, Cr, Sn, Cu or Fe can be plated at the same time, or Co, Cr, Sn, Cu or Fe can be plated after nickel plating. Through steps S1 to S3, a mesh 1 having a skeleton 5 with a blank inside is obtained. In order to obtain a mesh 1 having a skeleton 5 with a hollow inside, step S4 is performed.

[0109] Step S4

[0110] In step S4, the plated mesh intermediate is heat treated. By this heat treatment, the blank is removed and the inside of the skeleton 5 becomes hollow. The conditions of the heat treatment are not particularly limited. For example, the heat treatment temperature can be 800° C. or higher and 1200° C. or lower, and the heat treatment time can be 5 minutes or higher and 60 minutes or lower. In this way, a mesh 1 having a skeleton 5 with a hollow interior is obtained.

[0111] Step S5

[0112] Step S5 is a calendering process for adjusting the thickness of the web 1. The web 1 having a hollow skeleton 5 obtained in step S3 or the web 1 having a hollow skeleton 5 obtained in step S4 is calendered. Figure 3 As shown, the inner length of the mesh 1 in the thickness direction decreases, and the thickness of the mesh 1 decreases. The inner length of the mesh 1 in the thickness direction is smaller than the inner length in the in-plane direction of the mesh 1. In this way, the thickness of the mesh 1 is adjusted.

[0113] (Example)

[0114] The present embodiment will be described in more detail by way of examples, but the present embodiment is not limited to these examples.

[0115] ≪Preparation of mesh for samples 1 to 21≫

[0116] The meshes of Samples 1 to 21 were produced by the following method.

[0117] <Material preparation process>

[0118] A commercially available product was purchased to prepare a blank. The blank was formed of the resin described in Table 1 and had the same weaving method, wire diameter, mesh size, and pitch as described in Table 1.

[0119] <Net intermediate body forming process>

[0120] Using artificial graphite (conductive carbon particles) as a raw material containing carbon atoms and an acrylic binder, the artificial graphite (conductive carbon particles) is dispersed in the mass parts recorded in Table 1 relative to 100 mass parts of water (solvent), thereby preparing a conductive paste. Next, the conductive paste is applied to the surface of the blank. Next, the conductive paste is vacuum dried at 80° C. for 0.1 hour to volatilize water (solvent) from the conductive paste. In this way, a mesh intermediate is obtained.

[0121] <Plating process>

[0122] The mesh intermediate was subjected to nickel plating under the following plating bath composition and electrolytic conditions to obtain a mesh.

[0123] (Composition of plating bath)

[0124] Salt (aqueous solution): nickel sulfamate (nickel was contained in the plating bath at the concentrations listed in Table 2)

[0125] Boric acid: as shown in Table 2

[0126] pH: As shown in Table 2

[0127] (Electrolysis Conditions)

[0128] Temperature: 60℃

[0129] Current density: 10A / dm 2

[0130] Anode: Nickel pellet anode

[0131] Time: Adjust according to the type of metal and mass per unit area.

[0132] <Heat treatment process>

[0133] The meshes of samples 1 to 20 among the meshes of samples 1 to 21 are heat-treated under the conditions of the temperature and time described in Table 2, thereby obtaining meshes of samples 1 to 20 having a skeleton 5 with a hollow interior. The heat treatment process includes: a baking process of burning the resin in an air atmosphere; and a reduction process of reducing the metal components on the surface of the skeleton oxidized in the baking process in a reducing atmosphere. In addition, when the "Temperature [°C]" column and the "Time [minutes]" column in the "Heat Treatment Process" column of Table 2 are recorded as "-", it means that the heat treatment process is not implemented.

[0134] Through the above steps, samples 1 to 21 were manufactured in which "a net is composed of a skeleton having a plurality of support parts and node parts, and the node parts connect the support parts of the number listed in Table 3".

[0135] ≪Preparation of the mesh for sample 101≫

[0136] We purchased a nickel mesh (weight per unit area: 370 g / m 2 , pitch: 0.75mm, wire diameter: 0.15mm, mesh: 0.6mm, weaving method: plain weave), a mesh of sample 101 was prepared. In sample 101, the nickel wires were simply crossed, and the nickel wires were not connected to each other by metal bonding. Therefore, in sample 101, no node part was formed, and no support part connecting the node part was formed (see Table 3).

[0137] ≪Preparation of the mesh for sample 102≫

[0138] Sample 102, "a mesh having a skeleton having a plurality of pillars and node portions, wherein the node portions connect the pillars as many as described in Table 3", was prepared by the following method. First, a coating weight of 130 g / m 2 The mesh of Sample 101 was nickel plated in the following manner under the composition of the plating bath and electrolytic conditions.

[0139] (Composition of plating bath)

[0140] Salt (aqueous solution): nickel sulfamate (containing nickel at 90 g / L in the plating bath)

[0141] Boric acid: 20g / L

[0142] pH: 4

[0143] (Electrolysis Conditions)

[0144] Temperature: 60℃

[0145] Current density: 10A / dm 2

[0146] Anode: Nickel bead anode

[0147] Time: Adjust according to the type of metal and mass per unit area.

[0148] Next, heat treatment was performed at 1000° C. for 30 minutes, thereby obtaining a sample 102 in which “the net is composed of a skeleton having a plurality of pillars and node portions, wherein the node portions connect the pillars of the number described in Table 3”.

[0149] ≪Preparation of the mesh for sample 103≫

[0150] The mesh of sample 103 was prepared by the following method. First, artificial graphite (conductive carbon particles) as a raw material containing carbon atoms and an acrylic adhesive were used, and the artificial graphite (conductive carbon particles) was dispersed in 10 parts by mass relative to 100 parts by mass of water (solvent), thereby preparing a conductive slurry. Next, the conductive slurry was applied to the surface of a single fiber of polypropylene having a wire diameter of 180 μm. Next, the conductive slurry was vacuum dried under the conditions of 80°C and 0.1 hours. By volatilizing water (solvent) from the conductive slurry, a single fiber with conductivity was obtained. Next, the single fiber with conductivity was nickel-plated under the following composition of the plating bath and electrolysis conditions in a manner such that the average thickness of the plating was 5 μm. In addition, the average thickness of the plating was determined as follows: in a cross section perpendicular to the length direction of the single fiber at any five places in the single fiber having conductivity and nickel plating, the shortest distance from the surface of the single fiber to the surface of the plating was measured respectively, and the average value of the shortest distances at the five places was calculated.

[0151] (Composition of plating bath)

[0152] Salt (aqueous solution): nickel sulfamate (containing nickel at 90 g / L in the plating bath)

[0153] Boric acid: 20g / L

[0154] pH: 4

[0155] (Electrolysis Conditions)

[0156] Temperature: 60℃

[0157] Current density: 10A / dm 2

[0158] Anode: Nickel bead anode

[0159] Time: Adjust according to the type of metal and mass per unit area.

[0160] Next, the single fibers to which nickel plating was applied were woven in a plain weave manner, thereby obtaining a mesh intermediate having the following pitch and mesh size. Next, the mesh intermediate was heat treated at 1000°C for 30 minutes, thereby obtaining a mesh of sample 103. In sample 103, the single fibers to which nickel plating was applied were simply crossed, and the single fibers to which nickel plating was applied were not connected to each other by metal bonding. Therefore, in sample 103, no node portion was formed, and no support portion connecting the node portion existed (see Table 3).

[0161] [Table 1]

[0162]

[0163] [Table 2]

[0164]

[0165] [Table 3]

[0166]

[0167] ≪Network characteristic evaluation≫

[0168] <Structure of the frame>

[0169] The presence or absence of “a skeleton formed of a skeleton main body and an interior surrounded by the skeleton main body” was determined by the above method. The obtained results are recorded in the column “Presence or absence of skeleton main body + interior” in Table 3.

[0170] <Composition of the main frame>

[0171] The content of nickel in the skeleton body is determined by the above method. The obtained results are recorded in the "Ni content [mass %]" column of the "Skeleton body" column of Table 3. In addition, the content of the first atom in the skeleton body is determined by the above method. The obtained results are recorded in the "First atom content [mass %]" column of the "Skeleton body" column of Table 3.

[0172] <First ratio D2 / D1 and second ratio D4 / D3>

[0173] The first ratio D2 / D1 of the internal short diameter D2 to the internal long diameter D1 in the cross section at the center of the node portion along the length direction of one of the two or more pillar portions connected by the plurality of node portions is determined by the above method. The obtained result is recorded in the "D2 / D1" column of Table 3. In addition, the second ratio D4 / D3 of the internal second length D4 to the internal first length D3 in the cross section at the center of the pillar portion perpendicular to the length direction of one of the two or more pillar portions connected by the plurality of node portions is determined by the above method. The obtained result is recorded in the "D4 / D3" column of Table 3.

[0174] <Net opening ratio>

[0175] The mesh opening ratio was determined by the above method. The obtained results are recorded in the column "Mesh opening ratio [%]" in Table 3.

[0176] <Average equivalent circle diameter of the support portion in a cross section perpendicular to the longitudinal direction of the support portion>

[0177] The average equivalent circular diameter of the pillar portion in a cross section perpendicular to the longitudinal direction of the pillar portion was determined by the above method. The obtained results are recorded in the "Average equivalent circular diameter [mm]" column of Table 3.

[0178] <Mechanical strength of the net>

[0179] The mechanical strength of the mesh was determined by using "Autograph AGX-10NVD" (trademark) manufactured by Shimadzu Corporation. The obtained results are recorded in the "Mechanical strength [N / 10 mm]" column of Table 4. A relatively high value recorded in the "Mechanical strength [N / 10 mm]" column of Table 4 means that the mechanical strength of the mesh is excellent.

[0180] The meshes of samples 1 to 21 correspond to the examples of the present embodiment. The meshes of samples 101 to 103 correspond to the comparative examples. It is known that the meshes of samples 1 to 21 have particularly excellent mechanical strength compared to the meshes of samples 101 to 103.

[0181] <Network resistance>

[0182] The resistance of the mesh is determined by the following method. For each sample, a square mesh with a side length of 5 cm is prepared. Use the first clamping terminal to clamp the portion located 5 mm inward in the longitudinal and transverse directions of the mesh from the first corner of the square mesh. Use the second clamping terminal to clamp the portion located 5 mm inward in the longitudinal and transverse directions of the mesh from the second corner of the square mesh that is diagonally opposite to the first corner. A current is passed between the first clamping terminal and the second clamping terminal, and the resistance of the mesh is measured using the "BT3562 BATTERY HiTESTER" manufactured by Hioki Electric Co., Ltd. The results obtained in this way are recorded in the "Resistance [mΩ]" column of Table 4. The relatively low numerical value recorded in the "Resistance [mΩ]" column of Table 4 means that the resistance of the mesh is relatively low. It can be seen that the meshes of samples 1 to 21 have particularly low resistance compared to the meshes of samples 101 and 103.

[0183] <Mass per unit area of ​​the frame>

[0184] The mass per unit area of ​​the skeleton was determined by the above method. The results obtained are recorded in the "mass per unit area [g / m 2 ]” column. The relatively low mass per unit area of ​​the skeleton means that the net is relatively light. It can be seen that the nets of samples 1 to 21 are particularly light compared to the net of sample 102.

[0185] <Insulation evaluation test>

[0186] The insulation properties of the separator sandwiched between two nets were evaluated by the following method. First, a 20 μm thick polyethylene (PE) separator was sandwiched between two nets to obtain a laminate. The PE separator has insulation properties. Next, a 10 t / cm 2While applying a pressure, a current was passed between the two nets, and the resistance of the stack was measured. The insulation of the diaphragm sandwiched by the two nets was evaluated based on the following evaluation criteria. When the resistance of the stack is 10MΩ or more, evaluation criterion A is given. When the resistance of the stack is 100kΩ or more and less than 10MΩ, evaluation criterion B is given. When the resistance of the stack is less than 100kΩ, evaluation criterion C is given. The obtained results are recorded in the "Insulation" column of Table 4. In the present invention, insulation means the difficulty of leakage of the diaphragm. If the two nets become in a state of "short circuit", leakage of the diaphragm is likely to occur, and the insulation of the diaphragm is reduced. Evaluation criterion A or B means that even if pressure is applied to the stack, the diaphragm will not be damaged by the net, thereby ensuring the insulation of the diaphragm sandwiched by the two nets.

[0187] (Evaluation Criteria)

[0188] A: There is no short circuit

[0189] B: There is a slight short circuit

[0190] C: There is a short circuit

[0191] [Table 4]

[0192]

[0193] It can be seen that the insulation of the diaphragm sandwiched by the two meshes of samples 1 to 21 is superior to the insulation of the diaphragm sandwiched by the two meshes of samples 101 and 102. The reason is that the meshes of samples 1 to 21 have fewer irregularities on the surface of the mesh, so even if the laminate of the mesh and the diaphragm is pressurized, the diaphragm (for example, the diaphragm of a zero-gap water electrolysis cell, etc.) can be prevented from being damaged by the mesh.

[0194] As described above, the meshes of Samples 1 to 21 have excellent mechanical strength and low electrical resistance. In addition, according to the meshes of Samples 1 to 21, the insulation of the insulating member (eg, separator) sandwiched between two meshes can be ensured.

[0195] (Implementation Method 2)

[0196] refer to Figure 5 and Figure 6 , the net 1 of Embodiment 2 will be described. The net 1 of this embodiment is configured similarly to the net 1 of Embodiment 1, but is different from the net 1 of Embodiment 1 in that a plurality of grooves 17 are provided in the net 1 of this embodiment.

[0197] The net 1 has a main surface 10a and a main surface 10b opposite to the main surface 10a. The main surface 10a and the main surface 10b are separated from each other in the thickness direction of the net 1. When viewed from above, the net 1 has a first edge 11, a second edge 12 opposite to the first edge 11, a third edge 13, and a fourth edge 14 opposite to the third edge 13. The third edge 13 and the fourth edge 14 are connected to the first edge 11 and the second edge 12, respectively. In this specification, unless otherwise specified, the view from above means Figure 5 A top view of the main surface 10a is shown.

[0198] In a top view, the skeleton 5 has a lattice shape. In the present embodiment, the lattice may be a quadrilateral lattice, a triangular lattice, a hexagonal lattice, or the like. The plurality of lines 15 constituting the lattice extend from one of the first edge 11, the second edge 12, the third edge 13, and the fourth edge 14 to another of the first edge 11, the second edge 12, the third edge 13, and the fourth edge 14. Figure 5 In the case of the shape of the quadrilateral lattice as shown, the plurality of line bodies 15 are composed of a plurality of first line bodies 15a and a plurality of second line bodies 15b, and the lattice is formed by a plurality of first line bodies 15a and a plurality of second line bodies 15b. The plurality of first line bodies 15a extend from the first edge 11 to the second edge 12 respectively. The plurality of second line bodies 15b extend from the third edge 13 to the fourth edge 14 respectively.

[0199] A plurality of grooves 17 are formed on the main surface 10a of the net 1. For example, the plurality of grooves 17 are respectively elongated straight grooves. The plurality of grooves 17 are parallel to each other. When viewed from above, the plurality of grooves 17 extend in the same direction. The plurality of grooves 17 extend from the first edge 11 to the second edge 12, respectively. The length direction of each of the plurality of grooves 17 may also be parallel to the length direction of the second linear body 15b. The plurality of grooves 17 may also extend in parallel to the second linear body 15b, respectively.

[0200] The plurality of grooves 17 each have a depth d and a width W. The depth d is obtained by the difference between the height of the node portion 7 in the region where the plurality of grooves 17 are not formed in the mesh 1 and the height of the node portion 7 located in the groove 17. The depth d may be more than 10% of the thickness T of the mesh 1, and may be more than 30% of the thickness T of the mesh 1. The depth d may be less than 90% of the thickness T of the mesh 1. In the present embodiment, the thickness T of the mesh 1 is the thickness of the center of the node portion 7 where the plurality of grooves 17 are not formed. When viewed from above, the area of ​​the plurality of grooves 17 may be more than 10% of the area of ​​the main surface 10a, and may be more than 30% of the area of ​​the main surface 10a. When viewed from above, the area of ​​the plurality of grooves 17 may be less than 90% of the area of ​​the main surface 10a. In this specification, the area of ​​the plurality of grooves 17 means the total area of ​​the plurality of grooves 17 when viewed from above.

[0201] refer to Figure 7 The method for manufacturing the net 1 of this embodiment is described below. The method for manufacturing the net 1 of this embodiment includes: Figure 4 The steps of the method for manufacturing the net 1 of the first embodiment are the same as those of the method for manufacturing the net 1 of the first embodiment shown, but the method for manufacturing the net 1 of the present embodiment is different from the method for manufacturing the net 1 of the first embodiment in that it further includes a groove forming step (step S6).

[0202] The groove forming step (step S6) is performed after the calendering step (step S5). In the groove forming step (step S6), a plurality of grooves 17 are formed on the main surface 10a. Specifically, a mold (not shown) is pressed against the main surface 10a of the web 1. The shape of the convex portion of the mold is transferred to the main surface 10a. In this way, a web 1 having a plurality of grooves 17 formed on the main surface 10a is obtained.

[0203] refer to Figure 8 , a net 1 of a first variation of the present embodiment is described. In the net 1 of the variation of the present embodiment, the plurality of grooves 17 are inclined relative to the plurality of first linear bodies 15a and the plurality of second linear bodies 15b. In another variation of the present embodiment, the plurality of grooves 17 may also be formed in a concentric circle shape when viewed from above. The plurality of grooves 17 may also be formed in a spiral shape when viewed from above. Fig. 9 As shown, when viewed from above, the plurality of grooves 17 may also be formed radially. Fig.10 As shown, in a top view, the plurality of grooves 17 may also be respectively away from the first edge 11 , the second edge 12 , the third edge 13 and the fourth edge 14 , and the plurality of grooves 17 may be arranged in a grid shape.

[0204] like Fig.11 and Fig.12 As shown, in a top view, the plurality of grooves 17 may be formed by a plurality of first grooves 17a and a plurality of second grooves 17b intersecting the plurality of first grooves 17a. Fig.11 As shown, in a top view, the plurality of first grooves 17a may be parallel to the plurality of first line bodies 15a, and the plurality of second grooves 17b may be parallel to the plurality of second line bodies 15b. Fig.12 As shown, in a plan view, the first grooves 17a may be inclined relative to the first line bodies 15a and the second line bodies 15b, respectively, and the second grooves 17b may be inclined relative to the first line bodies 15a and the second line bodies 15b, respectively.

[0205] In the above modified examples of the present embodiment (see for example Figure 8 , Fig.10 and Fig.12In the modification examples shown in the figure, etc., each of the plurality of linear bodies 15 has a portion where the plurality of grooves 17 are not formed (hereinafter sometimes referred to as a "groove-unformed portion"). The minimum value of the ratio of the lengths of the groove-unformed portions of each of the plurality of linear bodies 15 is greater than 10%. Therefore, the mechanical strength of the net 1 is improved. The minimum value of the ratio of the lengths of the groove-unformed portions of each of the plurality of linear bodies 15 may be greater than 30%, or may be greater than 50%. In the present specification, the minimum value of the ratio of the lengths of the groove-unformed portions of each of the plurality of linear bodies 15 means the minimum value of the ratio of the lengths of the groove-unformed portions of the plurality of linear bodies 15 calculated by dividing the lengths of the groove-unformed portions of each of the plurality of linear bodies 15 by the total length of each of the plurality of linear bodies 15.

[0206] (Example)

[0207] The present embodiment will be described in more detail by way of examples, but the present embodiment is not limited to these examples.

[0208] The mesh of sample 34 is the same as the mesh of sample 1 of embodiment 1 (see Tables 1 to 4), but has the number of openings and thickness T shown in Table 5. The number of openings of the mesh is the number of openings per 1 inch (2.54 cm) length. Sample 34 does not have a plurality of slots 17.

[0209] The mesh of sample 31 is the same as the mesh of sample 34, but a layer such as Figure 5 The depth d and width of each of the plurality of grooves 17 and the intervals between adjacent grooves 17 are as shown in Table 5. In the mesh of sample 31, the plurality of grooves 17 extend parallel to the second linear body 15b, so the minimum value of the ratio of the groove-unformed portion of each of the plurality of linear bodies 15 is zero.

[0210] The meshes of Samples 32 and 33 are the same as the mesh of Sample 31, but in the meshes of Samples 32 and 33, a layer such as Figure 8 The plurality of grooves 17 are as shown. The plurality of grooves 17 are inclined relative to the plurality of first linear bodies 15a and the plurality of second linear bodies 15b, respectively. The minimum value of the ratio of the groove-unformed portion of each of the plurality of linear bodies 15 in the net of sample 32 and the minimum value of the ratio of the groove-unformed portion of each of the plurality of linear bodies 15 in the net of sample 33 are as shown in Table 5.

[0211] A solid oxide fuel cell (SOFC) was produced in which a fuel electrode current collector was formed by a mesh of one of Samples 31 to 34, and the power generation performance and thermal cycle characteristics of the SOFC were measured. The produced SOFC includes a fuel electrode connector, an air electrode connector, a solid electrolyte, an air electrode, a fuel electrode, a fuel electrode current collector, and an air electrode current collector.

[0212] The fuel electrode connector and the air electrode connector are formed of an iron-chromium alloy. The solid electrolyte is arranged between the fuel electrode connector and the air electrode connector. The solid electrolyte is formed of yttria-stabilized zirconia (YSZ). The fuel electrode is arranged between the fuel electrode connector and the solid electrolyte. The fuel electrode is a porous body formed of a composite of nickel (Ni) and yttria-stabilized zirconia (YSZ). The air electrode is arranged between the air electrode connector and the solid electrolyte. The air electrode is a porous body formed of lanthanum strontium cobalt (LSC). The fuel electrode current collector is arranged between the fuel electrode connector and the fuel electrode. The fuel electrode current collector is formed of a mesh of one of Samples 31 to 34. The air electrode current collector is arranged between the air electrode connector and the air electrode. The air electrode current collector is formed of silver paste.

[0213] The SOFC was heated to 760 degrees Celsius. Then, 0.4 liters / minute of hydrogen and 0.6 liters / minute of air were flowed into the SOFC. In this way, the power generation performance of the SOFC was measured. In addition, the thermal cycle characteristics of the SOFC were measured as follows. 2 While a current of 1000A flows through the SOFC, 20 cycles of thermal cycling are applied to the SOFC. In each thermal cycle, the temperature of the SOFC varies between 50 degrees Celsius and 760 degrees Celsius. The heating rate and cooling rate in each thermal cycle are 30 degrees / minute. The first output voltage of the SOFC is measured at a temperature of 760 degrees Celsius in the first cycle. The second output voltage of the SOFC is measured at a temperature of 760 degrees Celsius in the 20th cycle. The thermal cycle characteristics of the SOFC are obtained by expressing the ratio of the second output voltage to the first output voltage as a percentage.

[0214] The power generation performance and thermal cycle characteristics of the trial-produced SOFC are shown in Table 5. The power generation performance of the SOFC in which the fuel electrode current collector is formed by a mesh of one of Samples 31 to 33 is higher than the power generation performance of the SOFC in which the fuel electrode current collector is formed by a mesh of Sample 34. The reason for this is that by providing a plurality of grooves 17 in the fuel electrode current collector, the pressure loss of the gas in the fuel electrode current collector is reduced, and the uniformity of the flow of the gas in the fuel electrode current collector is improved.

[0215] The thermal cycle characteristics of the SOFC in which the fuel electrode current collector is formed of the mesh of one of Sample 32 and Sample 33 are superior to the thermal cycle characteristics of the SOFC in which the fuel electrode current collector is formed of the mesh of Sample 31. The reason for this is that the minimum value of the groove-unformed portion of the mesh of each of Sample 32 and Sample 33 is greater than the minimum value of the groove-unformed portion of the mesh of Sample 31, and the mesh of each of Sample 32 and Sample 33 has a higher mechanical strength than the mesh of Sample 31.

[0216] [Table 5]

[0217]

[0218] (Implementation method 3)

[0219] refer to Fig.13 , the water electrolysis device 20 of the third embodiment is described. The water electrolysis device 20 is, for example, a zero-gap alkaline water electrolysis device. The water electrolysis device 20 has bipolar plates 21, 22, a separator 23, a diaphragm 30, an anode 31, a cathode 32, a conductive elastic body 33, current collectors 34, 35, and conductive ribs 36, 37.

[0220] The bipolar plates 21 and 22 are flat plate-shaped members and are formed of, for example, an iron-chromium alloy.

[0221] The spacer 23 is disposed between the bipolar plate 21 and the bipolar plate 22. The spacer 23 defines the interval between the bipolar plate 21 and the bipolar plate 22. The spacer 23 is formed of an insulating material such as polytetrafluoroethylene (PTFE). The separator 30, the anode 31, the cathode 32, the conductive elastomer 33, and the current collectors 34 and 35 are accommodated in the internal space defined by the bipolar plates 21, 22 and the spacer 23.

[0222] The diaphragm 30 is disposed between the bipolar plate 21 and the bipolar plate 22. The diaphragm 30 is supported by the spacer 23. The diaphragm 30 divides the internal space defined by the bipolar plates 21, 22 and the spacer 23 into the anode chamber 28 and the cathode chamber 29. The diaphragm 30 is an insulator that can pass ions such as hydroxide ions. The diaphragm 30 is formed of, for example, polyphenylene sulfide (PPS).

[0223] The partition 23 is provided with inlets 24, 25 and outlets 26, 27. The inlet 24 and the outlet 26 are connected to the anode chamber 28. The inlet 25 and the outlet 27 are connected to the cathode chamber 29. The alkaline aqueous solution flows into the anode chamber 28 from the inlet 24, and flows into the cathode chamber 29 from the inlet 25. The alkaline aqueous solution is, for example, an aqueous potassium hydroxide (KOH) solution or an aqueous sodium hydroxide (NaOH) solution. Oxygen and the alkaline aqueous solution generated at the anode 31 flow out from the outlet 26. Hydrogen and the alkaline aqueous solution generated at the cathode 32 flow out from the outlet 27.

[0224] The anode 31 , the current collector 34 , and the conductive ribs 36 are disposed in the anode chamber 28 . The cathode 32 , the conductive elastic body 33 , the current collector 35 , and the conductive ribs 37 are disposed in the cathode chamber 29 .

[0225] The anode 31 is disposed between the bipolar plate 21 and the separator 30. The anode 31 may be in contact with the separator 30. The cathode 32 is disposed between the bipolar plate 22 and the separator 30. The cathode 32 may be in contact with the separator 30. The conductive elastomer 33 is disposed between the cathode 32 and the bipolar plate 22. The conductive elastomer 33 is in contact with the cathode 32.

[0226] The current collector 34 is disposed between the bipolar plate 21 and the anode 31. The current collector 34 is in contact with the anode 31. The current collector 34 is pressed against the anode 31 by the conductive rib 36 protruding from the bipolar plate 21. The current collector 35 is disposed between the bipolar plate 22 and the cathode 32. The current collector 35 is in contact with the cathode 32. The current collector 35 is pressed against the cathode 32 by the conductive rib 37 protruding from the bipolar plate 22.

[0227] At least one of the anode 31 , the cathode 32 , the current collector 34 , or the current collector 35 is formed of the mesh 1 of any one of Embodiment 1, Embodiment 2, and their modified examples.

[0228] The operation of the water electrolysis device 20 will be described.

[0229] The alkaline aqueous solution is supplied to the anode chamber 28 and the cathode chamber 29 of the water electrolysis device 20 through the inlet 24 and the inlet 25. A voltage is applied between the bipolar plate 21 and the bipolar plate 22 so that the potential of the cathode 32 is lower than the potential of the anode 31. At the cathode 32, water is reduced to generate hydrogen gas and hydroxide ions. The hydroxide ions move from the cathode 32 to the anode 31 through the diaphragm 30. At the anode 31, the hydroxide ions contained in the alkaline aqueous solution are oxidized to generate oxygen. The oxygen and the alkaline aqueous solution generated at the anode 31 flow out from the outlet 26. The hydrogen and the alkaline aqueous solution generated at the cathode 32 flow out from the outlet 27.

[0230] In addition, the water electrolysis device 20 is not limited to an alkaline water electrolysis device, and may be an anion exchange membrane water electrolysis device or the like.

[0231] The effects of the water electrolysis device 20 of this embodiment will be described.

[0232] The water electrolysis device 20 of this embodiment includes a current collector (current collector 34 or current collector 35), a diaphragm 30, and an electrode (anode 31 or cathode 32) disposed between the current collector and the diaphragm. At least one of the electrode and the current collector is formed by the mesh 1 of any one of Embodiment 1, Embodiment 2, and their modified examples.

[0233] Therefore, the uniformity of the flow of the aqueous solution in at least one of the electrode and the current collector can be improved. In addition, the discharge of the gas generated in the water electrolysis device 20 is promoted. The performance of the water electrolysis device 20 can be improved.

[0234] (Implementation 4)

[0235] refer to Fig.14 and Fig.15 , a fuel cell 40 according to Embodiment 4 will be described. The fuel cell 40 according to this embodiment is, for example, a solid oxide fuel cell (SOFC). Fig.14 The fuel cell 40 has connectors 41, 42, a fuel electrode current collector 43, a battery cell 44, an air electrode current collector 49, and a separator 50. Although not shown in the figure, the fuel cell 40 has a stack structure, which is formed by stacking a unit structure including connectors 41, 42, a fuel electrode current collector 43, a battery cell 44, an air electrode current collector 49, and a separator 50.

[0236] The connectors 41 and 42 are flat plate-shaped members. The connector 41 is formed, for example, of an iron-chromium alloy. Although not shown in the figure, the connector 42 is electrically connected to the connector 41. A groove 41a may be formed on the surface of the connector 41 that faces the fuel electrode current collector 43. A groove 42a may be formed on the surface of the connector 42 that faces the air electrode current collector 49. The connector 41 is provided with an inlet 41b and an outlet (not shown). The connector 42 is provided with an inlet 42b and an outlet (not shown).

[0237] The spacer 50 is disposed between the connector 41 and the connector 42. The spacer 50 defines the interval between the connector 41 and the connector 42. The spacer 50 is formed of an insulating material such as mica. The fuel electrode current collector 43, the battery cell 44, and the air electrode current collector 49 are accommodated in the internal space defined by the connectors 41, 42 and the spacer 50.

[0238] The cell 44 is disposed between the connector 41 and the connector 42. The fuel electrode current collector 43 is disposed between the connector 41 and the cell 44. The air electrode current collector 49 is disposed between the connector 42 and the cell 44. The cell 44 is disposed between the fuel electrode current collector 43 and the air electrode current collector 49.

[0239] refer to Fig.15 The battery cell 44 includes a fuel electrode 45, a solid electrolyte 46, and an air electrode 48. The battery cell 44 may further include an intermediate layer 47.

[0240] The fuel electrode 45 is a sheet-shaped porous body. The porous body constituting the fuel electrode 45 is formed of, for example, a composite of zirconium oxide (ZrO 2 ) and nickel. The fuel electrode 45 can be formed by applying a conductive material to the fuel electrode current collector 43 .

[0241] The solid electrolyte 46 is disposed between the fuel electrode 45 and the air electrode 48. The solid electrolyte 46 is in contact with the fuel electrode 45. The solid electrolyte 46 is a sheet-like member that allows oxygen ions to pass through. The solid electrolyte 46 is formed of, for example, yttria-stabilized zirconia (YSZ).

[0242] The air electrode 48 is a flat porous body. The porous body constituting the air electrode 48 is formed, for example, of (La, Sr)MnO3 or (La, Sr)CoO3. The air electrode 48 can also be formed by applying a conductive material to the air electrode current collector 49. In the case where the battery cell 44 does not include the intermediate layer 47, the air electrode 48 is in contact with the solid electrolyte 46. In the case where the battery cell 44 includes the intermediate layer 47, the air electrode 48 is in contact with the intermediate layer 47.

[0243] The intermediate layer 47 is disposed between the solid electrolyte 46 and the air electrode 48. The intermediate layer 47 prevents the reaction between the solid electrolyte 46 and the air electrode 48. The intermediate layer 47 is formed of, for example, Ce oxide (GDC) doped with Gd.

[0244] The fuel electrode current collector 43 is arranged between the connector 41 and the battery cell 44 (more specifically, the fuel electrode 45). The fuel electrode current collector 43 is in contact with the connector 41 and the battery cell 44 (more specifically, the fuel electrode 45). The air electrode current collector 49 is arranged between the connector 42 and the battery cell 44 (more specifically, the air electrode 48). The air electrode current collector 49 is in contact with the connector 42 and the battery cell 44 (more specifically, the air electrode 48).

[0245] In the fuel cell 40 of the present embodiment, at least one of the fuel electrode current collector 43 and the air electrode current collector 49 is formed of the mesh 1 of any one of Embodiment 1, Embodiment 2, and their modified examples.

[0246] The operation of the fuel cell 40 will be described.

[0247] The fuel gas is supplied to the fuel electrode current collector 43 and the fuel electrode 45 through the inlet 41b. The fuel gas is, for example, hydrogen (H2). The fuel gas diffuses throughout the fuel electrode current collector 43 and the fuel electrode 45 through the groove 41a.

[0248] Oxygen is supplied to the air electrode current collector 49 and the air electrode 48 through the inlet 42b. Oxygen diffuses to the entire air electrode current collector 49 and the entire air electrode 48 through the groove 42a. Oxygen ions move from the air electrode 48 to the fuel electrode 45 through the solid electrolyte 46. The oxygen ions reaching the fuel electrode 45 react with the hydrogen gas supplied to the fuel electrode 45 through the fuel electrode current collector 43. As a result, water (H2O) and electrons are generated. The electrons are supplied to the air electrode 48 through the connector 41, the connector 42 and the air electrode current collector 49, ionizing the oxygen supplied to the air electrode 48 through the air electrode current collector 49. By repeating the above reaction, the fuel cell 40 generates electricity.

[0249] The effects of the fuel cell 40 of this embodiment will be described.

[0250] The fuel cell 40 of this embodiment includes a current collector (fuel electrode current collector 43 or air electrode current collector 49), an electrolyte (solid electrolyte 46), and an electrode (fuel electrode 45 or air electrode 48) disposed between the current collector and the electrolyte. The current collector is formed by the mesh 1 of any one of Embodiment 1, Embodiment 2, and their modified examples.

[0251] Therefore, the pressure loss of the gas in the current collector can be reduced, and the uniformity of the flow of the gas in the current collector can be improved, thereby improving the performance of the fuel cell 40.

[0252] The first to fourth embodiments disclosed herein are illustrative in all aspects and are not restrictive. The scope of the present invention is indicated by the claims rather than the above embodiments, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0253] Description of Reference Numerals

[0254] 1: Net, 2: Skeleton body, 3: Interior, 4: Opening, 5: Skeleton, 6: Support, 7: Node, 10a, 10b: Main surface, 11: First edge, 12: Second edge, 13: Third edge, 14: Fourth edge, 15: Line body, 15a: First line body, 15b: Second line body, 17: Groove, 17a: First groove, 17b: Second groove, 20: Water electrolysis device, 21, 22: Bipolar plate, 23: Spacer, 24, 25, 41b, 42b: Inflow Mouth, 26, 27: outflow port, 28: anode chamber, 29: cathode chamber, 30: diaphragm, 31: anode, 32: cathode, 33: conductive elastomer, 34, 35: current collector, 36, 37: conductive ribs, 40: fuel cell, 41, 42: connector, 41a, 42a: groove, 43: fuel electrode current collector, 44: battery cell, 45: fuel electrode, 46: solid electrolyte, 47: intermediate layer, 48: air electrode, 49: air electrode current collector, 50: spacer.

Claims

1. A net, which is composed of a skeleton having a plurality of support parts and a plurality of node parts, The plurality of node portions are respectively connected to two or more support portions among the plurality of support portions, The skeleton is formed by a skeleton body and an interior surrounded by the skeleton body. The skeleton body is substantially formed of nickel or a nickel alloy.

2. The net according to claim 1, wherein In a cross section at the center of each of the plurality of node portions along the length direction of one of the two or more support portions, a first ratio of the inner short diameter to the inner long diameter is greater than or equal to 0.01 and less than or equal to 0.9, In a cross-section at the center of one of the pillar portions perpendicular to the length direction, a second ratio of a second length of the interior to a first length of the interior is greater than 0.1 and less than 1.0, the first length being the length of the interior in the in-plane direction of the net in the cross-section at the center of the one of the pillar portions, and the second length being the length of the interior in the thickness direction of the net in the cross-section at the center of the one of the pillar portions.

3. The net according to claim 1 or 2, wherein: The content of the first atom in the skeleton body is 0 ppm or more and 100 ppm or less on a mass basis, The first atom is at least one atom selected from a phosphorus atom and a boron atom.

4. The net according to any one of claims 1 to 3, wherein: The interior is hollow.

5. The net according to any one of claims 1 to 3, wherein: The inner portion is formed of an alkali-resistant resin or an alkali-resistant carbon fiber.

6. The net according to claim 5, wherein The alkali-resistant resin is at least one resin selected from polypropylene, polyethylene, polyester, nylon and polytetrafluoroethylene.

7. The net according to any one of claims 1 to 6, wherein: The mesh has an opening ratio of 0.2% or more and 80% or less.

8. The net according to any one of claims 1 to 7, wherein: The average equivalent circle diameter of each of the plurality of support portions in a cross section perpendicular to the longitudinal direction of each of the plurality of support portions is 0.007 mm or more and 0.5 mm or less.

9. The net according to any one of claims 1 to 8, wherein: The web has a major surface formed with grooves, The depth of the groove is more than 10% of the thickness of the mesh, When the main surface is viewed in plan, the area of ​​the groove is 10% or more of the area of ​​the main surface.

10. The net according to claim 9, wherein In the top view, the net has a first edge, a second edge opposite to the first edge, a third edge, and a fourth edge opposite to the third edge, the third edge and the fourth edge are connected to the first edge and the second edge respectively, In the plan view, the frame has a lattice shape, and a plurality of line bodies constituting the lattice extend from one of the first edge, the second edge, the third edge, and the fourth edge to the other of the first edge, the second edge, the third edge, and the fourth edge, respectively. The minimum value of the ratio of the length of the portion of each of the plurality of linear bodies where the groove is not formed is greater than 10%.

11. A water electrolysis device, comprising: current collector; Diaphragm; as well as an electrode disposed between the current collector and the separator, At least one of the electrode and the current collector is formed of the mesh according to any one of claims 1 to 10.

12. A fuel cell comprising: current collector; Electrolytes; and an electrode disposed between the current collector and the electrolyte, The current collector is formed of the mesh according to any one of claims 1 to 10.

Images