Composite member, method for manufacturing the same, and power storage device

Abstract

The present invention provides a composite member having an insulating coating film which does not require winding work and does not have problems of uneven winding, gaps, or peeling, and which can maintain excellent insulating properties and heat resistance for a long period. A composite member (1) has a base material (2) and an insulating coating film (3) that covers at least a portion of the surface of the base material (2), wherein the insulating coating film (3) has an inner layer (4) composed of a first coating film material containing a base (8) containing a compound having a siloxane bond and a scale-shaped, flat plate-shaped, flake-shaped, or fiber-shaped inorganic material (9) dispersed in the base (8), and an outer layer (5) composed of a second coating film material containing a base (8) containing a compound having a siloxane bond and a scale-shaped, flat plate-shaped, flake-shaped, or fiber-shaped inorganic material dispersed in the base (8), and the orientation of the inorganic material (9) with respect to the surface of the base material (2) is different between the inner layer (4) and the outer layer (5).

Description

Technical Field

[0001] This invention relates to composite components coated with an insulating film on a substrate and a method for manufacturing the same. Additionally, this invention relates to energy storage devices formed by connecting multiple battery cells or battery modules via composite components. Background Technology

[0002] To enable electrical connections between components, conductive members with an insulating coating formed on the surface of a metal sheet are used. For example, various electronic devices, electric or hybrid vehicles driven by electric motors, and storage batteries incorporate energy storage devices that connect multiple battery cells in series or parallel via busbars that serve as conductive members. Furthermore, the battery cells primarily utilize lithium-ion secondary batteries, which offer higher capacity and output compared to lead-acid and nickel-metal hydride batteries.

[0003] In a single battery cell, overcurrent sometimes flows during charging and discharging, causing the busbar to heat up and, depending on the situation, sometimes even produce flames. Therefore, in addition to insulation, busbars are also required to have heat resistance. For example, Patent Document 1 describes a busbar in which a ceramic strip, such as mica tape, is wound around a copper busbar body as a fire-resistant layer. Patent Document 2 describes a busbar in which copper sleeves are fixed to both ends of an aluminum body, and an insulating layer is impregnated on the surface.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Chinese Utility Model No. 216902355 Specification

[0007] Patent Document 2: Chinese Utility Model No. 218731641 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, in Patent Document 1, it is necessary to perform the operation of winding the ceramic strip around the busbar body. Due to space constraints in the placement of the battery cells, the busbar sometimes has a complex shape, but when the busbar has a complex shape, it is difficult to wind the ceramic strip to every corner of the busbar body. If there are uneven windings or gaps in the ceramic strip, sufficient insulation and heat resistance cannot be obtained. In addition, peeling of the adhesive surface of the ceramic strip can also be expected. Furthermore, a nylon strip is wound around the outside of the mica strip as an insulating layer, but the nylon strip is not heat-resistant, posing a problem in terms of heat resistance.

[0010] Furthermore, busbars with impregnated insulating layers, as in Patent Document 2, have the advantages of eliminating the need for ceramic tape winding and being easy to handle even complex busbar shapes. However, the film thickness is thinner at the corners of the busbar (see reference). Figure 1 Therefore, the corners are easily damaged, leading to poor insulation. Repeated dip coating and other methods to increase the film thickness at the corners have been considered, but this results in excessively thick film on the busbar's planar portion, or an increase in the amount of coating required for the insulation layer, thus increasing manufacturing costs.

[0011] Therefore, the present invention provides a composite component with an insulating film that does not require the winding operation of ceramic tape, and does not have problems such as uneven winding, gaps or peeling. The film thickness at the corners is also sufficient, and it exhibits excellent insulation and heat resistance even in complex shapes. The invention also provides a method for manufacturing the insulating film that can be easily manufactured.

[0012] Methods for solving problems

[0013] The above-mentioned objective of the present invention is achieved by the following [1] configuration of the composite component.

[0014] [1] A composite component having a substrate and an insulating film covering at least a portion of the surface of the substrate, characterized in that, The insulating coating comprises: an inner layer made of a first coating material and an outer layer made of a second coating material, wherein the first coating material contains a matrix comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, flakes, or fibers dispersed in the matrix; and the second coating material contains a matrix comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, flakes, or fibers dispersed in the matrix. In the inner layer and the outer layer, the orientation of the inorganic material relative to the surface of the substrate is different.

[0015] Furthermore, preferred embodiments of the composite components of the present invention relate to the following [2] to

[15] .

[0016] [2] According to the composite component described in [1], the orientation of the inorganic material in the inner layer is higher than that of the inorganic material in the outer layer.

[0017] [3] The composite component according to [2] is characterized in that the inner layer contains 60 to 100% inorganic material with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate, and the outer layer contains 10 to 80% inorganic material with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate.

[0018] [4] The composite component according to any one of [1] to [3] is characterized in that, The substrate has a pair of opposing main faces, a plurality of end faces connecting the main faces to each other, and corner portions between the main faces and the end faces. At least a portion of the insulating coating surrounds the corner of the substrate.

[0019] [5] The composite component according to [4] is characterized in that at least a portion of the insulating coating also surrounds the end face of the substrate.

[0020] [6] The composite component according to [4] or [5] is characterized in that the outer surface of the insulating coating formed at the corner of the substrate has an R shape in the cross-sectional shape along the corner of the substrate.

[0021] [7] The composite component according to any one of [1] to [6] is characterized in that the inner layer and the outer layer have the same composition.

[0022] [8] The composite component according to any one of [1] to [6] is characterized in that the inner layer and the outer layer have different compositions.

[0023] [9] The composite component according to any one of [1] to [8] is characterized in that the compound containing the siloxane bond in the first coating material and / or the second coating material is at least one of organosilicon and silica sol.

[0024]

[10] The composite component according to any one of [1] to [9] is characterized in that the inorganic material comprises at least one selected from silicon dioxide, alumina, mullite, zirconium oxide and calcium carbonate.

[0025]

[11] The composite component according to any one of [1] to [9] is characterized in that the inorganic material comprises at least one selected from glassy materials, mica, kaolin, talc, clay, pyrophyllite, montmorillonite, bentonite, wollastonite, calcareous silica, zeolite, diatomite and halloysite.

[0026]

[12] The composite component according to any one of [1] to [9] is characterized in that the inorganic material comprises at least one of a sheet-like glassy material and mica.

[0027]

[13] The composite component according to any one of [1] to

[12] is characterized in that at least one of the inner layer and the outer layer is impregnated with a matrix material comprising the compound having siloxane bonds.

[0028]

[14] The composite component according to any one of [1] to

[13] is characterized in that at least the portion of the substrate forming the inner layer is a rough surface.

[0029]

[15] The composite component according to any one of [1] to

[14] is characterized in that it has a resin layer on its outermost surface, the resin layer being composed of a resin different from the resin contained in the first coating material and the second coating material.

[0030] The above-mentioned objective of the present invention is achieved by the following

[16] configuration of the method for manufacturing composite components.

[0031]

[16] A method for manufacturing a composite component, which is a method for manufacturing a composite component according to any one of [1] to

[15] , characterized in that it comprises: The inner layer forming process involves coating at least a portion of the surface of the substrate with a coating comprising a first coating material and curing it. The first coating material contains a matrix material comprising a compound having siloxane bonds and an inorganic material in the form of flakes, plates, sheets, or fibers. The outer layer forming process involves applying a coating containing a second coating material to at least a portion of the surface of the inner layer using a coating method different from that used in the inner layer forming process, and then curing the coating material. The second coating material contains a matrix material comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, sheets, or fibers.

[0032] Furthermore, the preferred embodiments of the present invention regarding the manufacturing method of composite components relate to the following

[17] to

[23] .

[0033]

[17] The method for manufacturing the composite component according to

[16] is characterized in that the coating method in the inner layer forming process is dip coating, brush coating, spray coating or dot coating. The coating method in the outer layer forming process is dip coating, brush coating, or dispensing coating.

[0034]

[18] The method for manufacturing the composite component according to

[16] or

[17] is characterized in that the first coating material and the second coating material have the same composition.

[0035]

[19] The method for manufacturing the composite component according to

[16] or

[17] is characterized in that the first coating material and the second coating material have different compositions.

[0036]

[20] A method for manufacturing a composite component according to any one of

[16] to

[19] , characterized in that the compound containing the first coating material and / or the second coating material having a siloxane bond is at least one of organosilicon and silica sol.

[0037]

[21] A method for manufacturing a composite component according to any one of

[16] to

[20] is characterized in that, after at least one of the inner layer forming step and the outer layer forming step, there is an impregnation step for impregnating a matrix material containing the compound having siloxane bonds.

[0038]

[22] The method for manufacturing a composite component according to any one of

[16] to

[21] is characterized by having a roughening process for roughening the substrate.

[0039]

[23] The method for manufacturing a composite component according to any one of

[16] to

[22] is characterized by having the following resin layer forming step: coating the outermost surface with a resin material containing a resin different from the resin contained in the first coating material and the second coating material and curing it.

[0040] The above-mentioned objective of the present invention is achieved by the following configuration of the energy storage device

[24] .

[0041]

[24] An energy storage device, characterized in that multiple battery cells or battery modules are connected by a composite component as described in any one of [1] to

[15] .

[0042] Invention Effects

[0043] The insulating coating at the corners of the composite component of the present invention is thick enough to accommodate complex shapes. Furthermore, the insulating coating has inner and outer layers with different orientations of inorganic materials, thus possessing characteristics derived from these orientation differences. For example, if the orientation of the inorganic material in the inner layer is higher than that in the outer layer, the insulation and heat resistance in the inner layer are improved, and the impact resistance to external forces in the outer layer is improved, enabling long-term maintenance of insulation and heat resistance.

[0044] In addition, the manufacturing method of the composite component of the present invention does not require the winding operation of ceramic tape, and there are no problems such as uneven winding, gaps or peeling. It can make the insulating film at the corners thick enough and can easily handle complex shapes.

[0045] Furthermore, in the energy storage device of the present invention, multiple battery cells or battery modules are connected by a composite component with sufficient film thickness at the corners and excellent insulation and heat resistance, thus enabling long-term maintenance of safety. Attached Figure Description

[0046] Figure 1 The accompanying photograph is a substitute photograph obtained by taking a cross-section of the composite component of the present invention, showing the state in which the inner layer is formed.

[0047] Figure 2The accompanying photograph is a substitute photograph obtained by taking a cross-section of the composite component of the present invention, showing the state in which an outer layer is formed on an inner layer.

[0048] Figure 3A Yes Figure 2 The SEM image is obtained by taking a cross-section of the insulating film on the end face of the composite component shown.

[0049] Figure 3B yes Figure 3A An enlarged view of part A.

[0050] Figure 3C yes Figure 3A An enlarged view of part B.

[0051] Figure 4A This is an SEM image obtained by taking a cross-section of the insulating coating on the end face of the substrate, showing the cross-section of the insulating coating before impregnation treatment.

[0052] Figure 4B This is an SEM image obtained by taking a cross-section of the insulating coating on the end face of the substrate, showing the cross-section of the insulating coating after impregnation treatment following the formation of the inner and outer layers.

[0053] Figure 4C This is an SEM image obtained by taking a cross-section of the insulating coating on the end face of the substrate, showing the cross-section of the insulating coating formed after the inner layer is impregnated.

[0054] Figure 4D This is an SEM image obtained by taking a cross-section of the insulating film on the end face of the substrate, showing the cross-section of the insulating film on which the outer layer is formed after impregnation treatment of the inner layer, and the outer layer is also impregnated.

[0055] Figure 5A This is an SEM image obtained by taking a cross-section of the insulating coating at the corner of the substrate, showing the cross-section of the insulating coating before impregnation treatment.

[0056] Figure 5B This is an SEM image obtained by taking a cross-section of the insulating film at the corner of the substrate, showing the cross-section of the insulating film after impregnation treatment following the formation of the inner and outer layers.

[0057] Figure 5C This is an SEM image obtained by taking a cross-section of the insulating film at the corner of the substrate, showing the cross-section of the insulating film that forms the outer layer after the inner layer is impregnated.

[0058] Figure 5DThis is an SEM image obtained by taking a cross-section of the insulating film at the corner of the substrate, showing the cross-section of the insulating film on which the outer layer is formed after impregnation treatment of the inner layer, and the outer layer is also impregnated.

[0059] Figure 6 This is a perspective view showing a busbar as an example of a composite component.

[0060] Figure 7 This illustrates an example of a power storage device according to the present invention. Figure 6 The diagram shows a battery pack for the busbar. Detailed Implementation

[0061] The inventors conducted in-depth research to eliminate the need for winding insulating tapes like ceramic tapes, to handle complex shapes, and to solve the problem of thinning of the insulating coating at corners. The results showed that, after forming the inner layer composed of a first coating material, it is effective to form the outer layer composed of a second coating material at the thinner corners using a coating method different from the coating method used when coating the first coating material.

[0062] Hereinafter, embodiments of the present invention (hereinafter referred to as "this embodiment") will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited to the embodiments described below, and can be implemented in any way without departing from the spirit of the present invention.

[0063] [Composite Components]

[0064] Figure 1 and Figure 2 This is a photographic representation of the composite member 1 of this embodiment, shown along the thickness direction of the substrate 2. An insulating film 3 is formed on at least a portion of the substrate 2. The insulating film 3 is composed of an inner layer 4 and an outer layer 5, sequentially arranged from the side closest to the substrate 2. Figure 1 This shows the state in which the inner layer 4 is formed. Figure 2 This shows the state where the outer layer 5 is formed on the inner layer 4.

[0065] The substrate 2 has a pair of opposing main faces 2a, 2a; a plurality of end faces 2b connecting the main faces 2a to each other; and a corner 2c between the main faces 2a and the end faces 2b, as shown in the figure. The cross-section of the corner 2c can be R-shaped. That is, the outer surface of the insulating film 3 formed on the corner 2c of the substrate 2 has an R-shape along the cross-sectional shape of the corner 2c of the substrate 2.

[0066] Furthermore, to improve the adhesion with the inner layer 4, the substrate 2 can be roughened by sandblasting or other methods. The degree of roughening is preferably 1 μm or more, more preferably 2 μm or more, as specified in JIS B 0031. It should be noted that the surface roughness Ra represents the average value of the surface roughness measured at any three points on the surface of the substrate 2.

[0067] Furthermore, in this embodiment, the inner layer 4 is formed on the main face 2a, the end face 2b, and the corner 2c of the substrate 2.

[0068] The inner layer 4 is a layer containing a matrix 8 comprising a compound having siloxane bonds (preferably organosilicon) and an inorganic material 9 dispersed in the matrix 8 in the form of flakes, plates, sheets, or fibers. Furthermore, as described later, the inner layer 4 is a layer obtained by coating and curing a first coating material containing a matrix material comprising a compound having siloxane bonds (preferably organosilicon) and the inorganic material 9 in the form of flakes, plates, sheets, or fibers.

[0069] However, the film thickness of the inner layer 4 of the end portion 2b and corner portion 2c of the substrate 2, especially the corner portion 2c, is thinner than that of the inner layer 4 of the main portion 2a, which may result in insufficient insulation and heat resistance. Therefore, as Figure 2 As shown, the outer layer 5 is formed in such a way that the inner layer 4 surrounds the end portion 2b and corner portion 2c of the substrate 2.

[0070] The outer layer 5 is a layer containing a matrix 8 comprising a compound having siloxane bonds (preferably organosilicon) and an inorganic material 9 dispersed in the matrix 8 in the form of flakes, plates, sheets, or fibers. Furthermore, as described later, the outer layer 5 is a layer obtained by coating a second coating material containing a matrix material having siloxane bonds (preferably organosilicon) and the inorganic material 9 in the form of flakes, plates, sheets, or fibers, and then curing it.

[0071] It should be noted that both the compounds with siloxane bonds and the inorganic material 9 are materials with excellent heat resistance and insulation. Therefore, if the compounds with siloxane bonds and the inorganic material 9 are included as components of the matrix 8 in the inner layer 4 or the outer layer 5, an insulating coating (inner layer 4 or outer layer 5) with excellent heat resistance and insulation can be made.

[0072] Furthermore, examples of compounds containing siloxane bonds (Si-O-Si bonds) include organosilicon and silica sol (silicon dioxide: SiO2). From the viewpoint of excellent heat resistance and insulation, the compound containing siloxane bonds in the matrix 8 of the inner layer 4 (first coating material) or the outer layer 5 (second coating material) is preferably at least one of organosilicon and silica sol, more preferably organosilicon. Additionally, it is also preferable to include both organosilicon and silica sol in the matrix 8 of the inner layer 4 (first coating material) or the outer layer 5 (second coating material).

[0073] Figure 3A This is an SEM image obtained by photographing a cross-section of the insulating film 3 on the end face 2b of the substrate 2. The end face 2b of the substrate 2 is located at the bottom of the image, and an inner layer 4 and an outer layer 5 are formed on it. Additionally, the whitish lines in the image represent inorganic material 9. Since inorganic material 9 is flaky, plate-like, sheet-like, or fibrous, its cross-sectional shape appears as lines. The gray areas in the image represent the matrix 8, which surrounds the inorganic material 9. The black areas in the image represent pores 10.

[0074] in addition, Figure 3B yes Figure 3A An enlarged view of section A of inner layer 4. Figure 3C yes Figure 3A An enlarged view of part B of the outer layer 5. (See image below.) Figure 3B As shown, in the inner layer 4, the inorganic material 9 is generally arranged in a neat and parallel manner relative to the surface of the substrate 2 (here, end face 2b), exhibiting a "high orientation" state. In contrast, in the outer layer 5, as... Figure 3C As shown, the tilt angles of the inorganic material 9 relative to the surface of the substrate 2 are different, and the inorganic material 9 is in a state of "low orientation".

[0075] Thus, the composite component 1 of this embodiment is characterized in that the insulating film 3 is composed of an inner layer 4 and an outer layer 5, in which the orientation of the inorganic material 9 is different from that of the inner layer 4 and the outer layer 5. This is because, as will be explained in the manufacturing method described later, the coating method of the first film material used to form the inner layer 4 is different from that of the second film material used to form the outer layer 5.

[0076] It should be noted that, as long as the orientation of the inorganic materials 9 is different, the orientation in the inner layer 4 can be low and the orientation in the outer layer 5 can be high, contrary to the above. However, when the orientation of the inorganic materials 9 is consistent, the insulation performance is higher; on the other hand, when the orientation of the inorganic materials 9 is inconsistent, the strength against external impacts is increased. Therefore, as described above, by making the orientation of the inorganic materials 9 high in the inner layer 4 and the orientation of the inorganic materials 9 low in the outer layer 5, the electrical properties are high, and damage to the insulating film 3 and peeling from the substrate 2 can be suppressed when the composite components 1 are in contact with each other or with other components.

[0077] Furthermore, as described above, when the orientation of the inorganic material 9 in the inner layer 4 is higher than that of the inorganic material 9 in the outer layer 5, the inner layer 4 contains 60 to 100% of the inorganic material 9 with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate 2, and the outer layer 5 contains 10 to 80% of the inorganic material 9 with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate 2. This results in high electrical properties, and more effectively suppresses damage to the insulating film 3 and peeling from the substrate 2 when the composite components 1 come into contact with each other or with other components. From this perspective, it is particularly preferred.

[0078] It should be noted that there are no restrictions on the film thickness of the inner layer 4 and the outer layer 5. For the inner layer 4, a thickness of 100–800 μm at the main surface area 2a of the substrate 2 and 30–400 μm at the end surface area 2b and corner area 2c of the substrate 2 is appropriate. Similarly, for the outer layer 5, a thickness of 0–400 μm at the main surface area 2a of the substrate 2 and 50–800 μm at the end surface area 2b and corner area 2c of the substrate 2 is appropriate.

[0079] In addition, such as Figures 3A-3C As shown, the insulating film 3 contains scattered pores 10, which may reduce insulation, heat resistance, and film strength. Therefore, the inner layer 4 and outer layer 5 are further impregnated with a matrix material containing a compound with siloxane bonds (preferably organosilicon). Compounds with siloxane bonds, especially organosilicon, have excellent insulation and heat resistance. By allowing these substances to flow into and fill the pores 10, insulation and heat resistance are improved, and the insulating film becomes denser, thus increasing film strength. It should be noted that the impregnation can be performed only on the inner layer 4 or only on the outer layer 5; preferably, both the inner layer 4 and the outer layer 5 are impregnated.

[0080] Figures 4A to 4D All are SEM images showing the cross-section of the insulating film 3 on the end face 2b of the substrate 2. Figure 4A The cross-section of the insulating film 3 before impregnation treatment is shown. Both the inner layer 4 and the outer layer 5 are scattered with numerous black pores 10. In contrast, as shown... Figure 4BAs shown, after the formation of the inner layer 4 and the outer layer 5, when impregnating a matrix material containing organosilicon (a compound with siloxane bonds), the pores 10 of the outer layer 5 are mainly filled by the organosilicon-containing matrix material, thus reducing the number of pores 10. Additionally, as... Figure 4C As shown, if a matrix material containing organosilicon is impregnated after the formation of the inner layer 4, the number of pores 10 in the inner layer 4 decreases. Furthermore, as... Figure 4D As shown, if an outer layer 5 is formed on an inner layer 4 after impregnation with a matrix material containing organosilicon, and an outer layer 5 is also impregnated with a matrix material containing organosilicon, then the number of pores 10 in both the inner layer 4 and the outer layer 5 will decrease.

[0081] In addition, the cross-section of the insulating film 3 at corner 2c is also the same. Figure 5A The cross-section of the insulating film 3 before impregnation treatment is shown, with numerous pores 10 scattered throughout both the inner layer 4 and the outer layer 5. In contrast, as... Figure 5B As shown, during the impregnation of a silicone-containing matrix material after the formation of the inner layer 4 and the outer layer 5, the pores 10 of the outer layer 5 are mainly filled by the silicone-containing matrix material, thus reducing the number of pores 10. Additionally, as... Figure 5C As shown, if a matrix material containing organosilicon is impregnated after the formation of the inner layer 4, the number of pores 10 in the inner layer 4 decreases. Furthermore, as... Figure 5D As shown, if an outer layer 5 is formed on an inner layer 4 after impregnation with a matrix material containing organosilicon, and an outer layer 5 is also impregnated with a matrix material containing organosilicon, then the number of pores 10 in both the inner layer 4 and the outer layer 5 will decrease.

[0082] Although the illustration is omitted, the inner layer 4 and outer layer 5 can be surrounded by a resin layer as needed. This resin layer is composed of a resin different from the resin contained in the inner layer 4 and outer layer 5, further improving the insulation, heat resistance, and impact resistance of the insulating coating 3. To achieve these effects, the thickness of the resin layer is preferably 100 μm or more, more preferably 120 μm or more, and even more preferably 150 μm or more. Furthermore, if the thickness of the resin layer is 600 μm or less, it will not affect the dimensions of the composite component 1, and it can also suppress the increase in manufacturing costs. Therefore, the thickness of the resin layer is preferably 600 μm or less, more preferably 550 μm or less, and even more preferably 500 μm or less.

[0083] The composite component 1 is constructed as described above. The preferred materials for the substrate 2, inner layer 4, outer layer 5 and resin layer are illustrated below.

[0084] (Substrate 2)

[0085] The main body of various products using composite component 1 can be used as substrate 2. For example, when composite component 1 is applied to a busbar, a conductive busbar body can be used as substrate 2. It should be noted that although the busbar body is conductive and the substrate itself is energized, the substrate 2 covered by the insulating film 3 is not limited to a conductive substrate. For example, a substrate made of a non-energized material can also be used.

[0086] (Inner layer 4)

[0087] The inner layer 4 is composed of a first coating material containing a matrix 8 comprising a compound having siloxane bonds and an inorganic material 9 in the form of flakes, plates, sheets, or fibers. As a preferred example of a compound having siloxane bonds, organosilicon is heated during the curing of the first coating material in the manufacturing method described later. Through heating, the functional groups disappear, and SiO bonds are generated. Furthermore, when a fire occurs near the composite component 1, or when the insulating coating 3 is heated to a temperature of, for example, 700°C or higher, SiO2 is generated through thermal decomposition. The generated SiO2 will not burn off even when exposed to flame; therefore, the inner layer 4 containing organosilicon can obtain excellent heat resistance and will not peel off from the substrate 2. It should be noted that organosilicon includes organosilicon resin and silicone rubber; both are acceptable, but from the viewpoint of achieving a high density of the formed SiO2, organosilicon resin is preferred.

[0088] The matrix 8 can be a single organosilicon, or it can contain other materials such as flame retardants, dispersants, and pigments, within a range that does not affect the insulation and heat resistance. Furthermore, to improve the coating performance of the first coating material, a thixotropic agent is preferably included.

[0089] (Inorganic Materials 9)

[0090] The inorganic material 9 contained in the first coating material has an aspect ratio of 10 or more, thus exhibiting an appearance such as flakes, flat sheets, thin sheets, or fibers, and requires a high melting point and excellent heat resistance. In addition, it also helps to serve as the skeleton of the inner layer 4 (and also helps to serve as the skeleton of the outer layer 5, which will be described later).

[0091] It should be noted that in this embodiment, "aspect ratio" refers to the ratio of the major diameter b to the minor diameter a (b / a) of the material, representing the average value of a large number of inorganic materials (particles) present in the inner layer 4 or the outer layer 5. Furthermore, to further enhance the effects of the present invention, the aforementioned aspect ratio is preferably 15 or more, and more preferably 20 or more.

[0092] As a specific material name, a silicate compound is preferred. As described above, organosilicon, as an example of a compound containing siloxane bonds, can be thermally decomposed into SiO2, and the silicate compound has the same composition as the SiO2 formed by organosilicon, thus improving the bonding strength between the organosilicon-containing matrix 8 and the inorganic material 9. It should be noted that the silicate compound is preferably selected from at least one of glassy materials, mica, kaolin, talc, clay, pyrophyllite, montmorillonite, bentonite, wollastonite, calcareous silica, zeolite, diatomaceous earth, and halloysite.

[0093] It should be noted that, as another preferred example of a compound with siloxane bonds, the main component of silica sol (silica) is SiO2. Since silicate compounds have the same composition as silica sol (SiO2), they can also improve the bonding force between the matrix 8 containing silica sol (silica) and the inorganic material 9.

[0094] Furthermore, the inorganic material 9 preferably includes at least one selected from silicon dioxide, alumina, mullite, zirconium oxide, and calcium carbonate. These materials have high melting points and high insulation properties. In the case of a busbar as an example of the composite component 1, the envisioned heat exposure temperature of the busbar is above the melting point of the metallic material typically used in the busbar body. Since these materials have melting points above the heat exposure temperature, it is preferable to suppress the exposure of the busbar body to high heat.

[0095] The content of inorganic material 9 relative to the total components of the first coating material is preferably 3 to 70% by volume, more preferably 10 to 50% by volume, and even more preferably 20 to 40% by volume. When the content of inorganic material 9 is less than 3% by volume, it may be impossible to obtain sufficient insulation and heat resistance. On the other hand, when it exceeds 70% by volume, the viscosity of the coating liquid becomes too high, resulting in poor film formation.

[0096] (Outer layer 5)

[0097] The outer layer 5 is composed of a second coating material containing a matrix 8 comprising organosilicon and an inorganic material 9 in the form of flakes, plates, sheets, or fibers. The second coating material may have the same composition as the first coating material described above; therefore, the preferred material names and the content of the inorganic material 9 are omitted here. Alternatively, the second coating material may have a different composition from the first coating material. This can be achieved by selecting a material different from the preferred materials listed above, or by changing the content of the inorganic material 9, etc.

[0098] (Resin layer)

[0099] The resin forming the resin layer only needs to be different from the resin contained in the inner layer 4 and the outer layer 5. It is preferred to use a heat-resistant resin, such as epoxy resin, nylon resin, SBR (styrene-butadiene rubber), silicone rubber, PVC (polyvinyl chloride), etc.

[0100] [Manufacturing Method of Composite Components]

[0101] The manufacturing method of the composite component 1 according to this embodiment will be described below, for example, as shown in <Manufacturing Method 1> and <Manufacturing Method 2>. In order to make the orientation of the inorganic material 9 different in the inner layer 4 and the outer layer 5 as described above, it is only necessary to change the coating method of the first coating material forming the inner layer 4 and the second coating material forming the outer layer 5. It should be noted that the manufacturing method described below applies to the case where the compound containing siloxane bonds in the matrix is ​​organosilicon, but it is also applicable when the compound containing siloxane bonds is silica sol (silica).

[0102] <Manufacturing Method 1>

[0103] (Inner layer formation process)

[0104] A first coating material is applied to the substrate 2. The coating method can include dip coating, brush coating, spray coating, or dispensing coating. Next, the coating of the first coating material is dried at a temperature of, for example, 50°C, to allow the organic solvents in the first coating material to evaporate. This forms the first layer, which serves as the inner layer 4.

[0105] (Outer layer formation process)

[0106] Next, a second coating material is applied to the first layer. As a coating method, localized dipping, brushing, or dispensing can be used to apply the second coating material locally to areas where the first layer is thinner, such as the end face 2b and corners 2c. The coating is performed using a different method than that used for the first layer. After coating, the second coating material is dried, for example, at a temperature of 50°C, to allow the organic solvents in the second coating material to evaporate. This forms the second layer, which is the outer layer 5.

[0107] Then, after the first and second layers are formed, they are heated, for example, at a temperature of 200°C, to cure both layers. Through this heating, the organosilicon (a compound with siloxane bonds) undergoes dehydration and condensation, forming a three-dimensional network structure and generating pores 10. Therefore, a matrix material containing organosilicon is impregnated into the first and second layers. To achieve this impregnation, after drying, an impregnation process is performed, such as immersion in a solution containing the organosilicon-containing matrix material. It should be noted that, to further reduce the pores 10, the impregnation process can be repeated multiple times.

[0108] In this way, a composite component 1 is manufactured having an insulating film 3 consisting of an inner layer 4 and an outer layer 5.

[0109] Alternatively, the insulating film 3 can be surrounded by a resin layer if needed. To form the resin layer, for example, an epoxy resin coating is applied to the insulating film 3 and allowed to dry and cure. It should be noted that, in the case of forming a resin layer, a portion of the material constituting the resin layer can also permeate into the first and second layers.

[0110] <Manufacturing Method 2>

[0111] In the manufacturing method 1 described above, after forming the first layer and the second layer, both layers are cured. Here, the first layer is cured, an impregnation process is performed to form the inner layer 4, a second layer is formed on the inner layer 4 and cured, and an impregnation process is performed to form the outer layer 5.

[0112] Alternatively, the insulating film 3 can also be surrounded by a resin layer.

[0113] It should be noted that the coating amount of the first coating material and the second coating material is adjusted so that the cured film thickness is the preferred film thickness mentioned above.

[0114] Alternatively, the substrate 2 can be roughened, or sandblasting can be applied.

[0115] It should be noted that in the above manufacturing method, the first coating material (coating solution) is obtained by adding a material containing an organosilicon matrix and an inorganic material to an organic solvent. In addition, the second coating material (coating solution) is obtained by adding a material containing an organosilicon matrix to an organic solvent without inorganic material. However, in the case of silica sol (silica), the composite component of the present invention can be obtained even without performing the above impregnation process, depending on the type of the first coating material and the second coating material.

[0116] [Specific application example of composite component 1]

[0117] Products using composite component 1 can be applied to busbars, connectors, battery modules, battery packs and other energy storage devices, housings of electronic components, and coils of electric motors. The following is an example of a busbar.

[0118] Figure 6The diagram shows the busbar 100 before it is installed on the battery cell 130. The busbar body 110, which serves as the substrate 2, is, for example, a Z-shaped metal plate component. It is secured by inserting the electrode 135 of the battery cell 130 into a connection hole 115a at one end and then fitting a terminal cap 136. Additionally, an adjacent battery cell (not shown) and an external device (not shown) are connected to another connection hole 115b at the other end of the busbar body 110. Furthermore, the area of ​​the busbar body 110, excluding the connection holes 115a and 115b, is covered by the aforementioned insulating film 3. This constitutes the busbar 100.

[0119] When the busbar body 110 has a shape with a Z-shaped bend 110a or a curved portion (not shown), as illustrated, the following problems arise. For example, in the manner shown in Patent Document 1, where the ceramic tape is wound around the busbar body 110, the winding operation is time-consuming in order to prevent uneven winding or gaps from occurring at the bend 110a or curved portion. Furthermore, it is conceivable that gaps may occur between the ceramic tapes due to vibration or the adhesive between the ceramic tapes and the busbar body 110 may peel off.

[0120] In contrast, in the busbar 100 of this embodiment, there is no need to wind the tape onto the busbar body 110; an insulating film 3 with insulation, heat resistance, and high strength can be formed on the surface of the busbar body 110. Furthermore, since there is no need to wind the tape onto the busbar body 110, there are no problems such as uneven winding, gaps, or peeling, and complex shapes can be easily handled.

[0121] [Electronic Storage Device]

[0122] This embodiment also relates to an energy storage device. Figure 7 Through Figure 6 The diagram shows a power storage device 200 in which a busbar 100 connects multiple battery cells 130, 130 and houses them within a housing 210. It should be noted that the power storage device 200 can be... Figure 7 As shown, multiple battery cells 130, 130 are connected via... Figure 6 The configuration shown, where the busbar 100 is connected and housed in the housing 210, can also be used to connect multiple battery modules (not shown). Figure 6 The busbar 100 shown is connected to and housed in the housing 210.

[0123] Busbar 100 is covered by the insulating film 3 of this embodiment described above. Therefore, even if a battery cell 130 experiences thermal runaway, it can protect adjacent battery cells 130, resulting in excellent safety.

[0124] Various embodiments have been described above with reference to the accompanying drawings, but the present invention is not limited to these examples. It should be understood that various modifications or alterations will be readily apparent to those skilled in the art within the scope of the claims, and these modifications also fall within the technical scope of the present invention. Furthermore, the constituent elements of the above embodiments can be combined arbitrarily without departing from the spirit of the invention.

[0125] Furthermore, this application is based on Japanese Patent Application No. 2024-056201, filed on March 29, 2024, the contents of which are incorporated herein by reference.

[0126] Explanation of reference numerals in the attached figures

[0127] 1 Composite Components

[0128] 2. Substrate

[0129] 3. Insulating film

[0130] 4 Inner layer

[0131] 5 Outer layer

[0132] 8. Matrix

[0133] 9 Inorganic Materials

[0134] 10 pores

[0135] 100 bus

[0136] 110 Busbar Main Body

[0137] 110a flexion

[0138] 130 battery cell

[0139] 135 electrode

[0140] 200 energy storage device

[0141] 210. Shell.

Claims

1. A composite component having a substrate and an insulating film covering at least a portion of the surface of the substrate, characterized in that, The insulating coating comprises: an inner layer made of a first coating material and an outer layer made of a second coating material, wherein the first coating material contains a matrix comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, flakes, or fibers dispersed in the matrix; and the second coating material contains a matrix comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, flakes, or fibers dispersed in the matrix. In the inner layer and the outer layer, the orientation of the inorganic material relative to the surface of the substrate is different.

2. The composite component according to claim 1, characterized in that, The orientation of the inorganic material in the inner layer is higher than that of the inorganic material in the outer layer.

3. The composite component according to claim 2, characterized in that, The inner layer contains 60% to 100% inorganic material with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate, and the outer layer contains 10% to 80% inorganic material with an orientation direction of 0 to 10 degrees relative to the direction parallel to the surface of the substrate.

4. The composite component according to claim 1, characterized in that, The substrate has a pair of opposing main faces, a plurality of end faces connecting the main faces to each other, and corner portions between the main faces and the end faces. At least a portion of the insulating coating surrounds the corner of the substrate.

5. The composite component according to claim 4, characterized in that, At least a portion of the insulating coating also surrounds the end face of the substrate.

6. The composite component according to claim 4, characterized in that, The outer surface of the insulating coating formed at the corner of the substrate has an R-shape in the cross-sectional shape along the corner of the substrate.

7. The composite component according to claim 1, characterized in that, The inner layer and the outer layer have the same composition.

8. The composite component according to claim 1, characterized in that, The inner layer and the outer layer have different compositions.

9. The composite component according to claim 1, characterized in that, The compound containing the siloxane bond in the first coating material and / or the second coating material is at least one of organosilicon and silica sol.

10. The composite component according to claim 1, characterized in that, The inorganic material comprises at least one selected from silicon dioxide, alumina, mullite, zirconium oxide, and calcium carbonate.

11. The composite component according to claim 1, characterized in that, The inorganic material comprises at least one selected from glassy materials, mica, kaolin, talc, clay, pyrophyllite, montmorillonite, bentonite, wollastonite, calcareous silica, zeolite, diatomite, and halloysite.

12. The composite component according to claim 1, characterized in that, The inorganic material comprises at least one of a sheet-like glassy material and mica.

13. The composite component according to claim 1, characterized in that, At least one of the inner layer and the outer layer is impregnated with a matrix material containing the compound having siloxane bonds.

14. The composite component according to claim 1, characterized in that, At least the portion of the substrate forming the inner layer is a rough surface.

15. The composite component according to claim 1, characterized in that, The outermost surface has a resin layer, which is composed of a resin different from the resin contained in the first coating material and the second coating material.

16. A method for manufacturing a composite component, wherein the method for manufacturing a composite component according to any one of claims 1 to 15 is characterized in that, have: The inner layer forming process involves coating a coating containing a first coating material onto at least a portion of the surface of the substrate and curing it. The first coating material contains a matrix material comprising a compound having siloxane bonds and an inorganic material in the form of flakes, plates, flakes, or fibers. as well as The outer layer forming process involves applying a coating containing a second coating material to at least a portion of the surface of the inner layer using a coating method different from that used in the inner layer forming process, and then curing the coating material. The second coating material contains a matrix material comprising a compound having siloxane bonds and inorganic materials in the form of flakes, plates, sheets, or fibers.

17. The method for manufacturing the composite component according to claim 16, characterized in that, The coating method in the inner layer formation process is dip coating, brush coating, spray coating, or dispensing coating. The coating method in the outer layer forming process is dip coating, brush coating, or dispensing coating.

18. The method for manufacturing the composite component according to claim 16, characterized in that, The first coating material and the second coating material have the same composition.

19. The method for manufacturing the composite component according to claim 16, characterized in that, The first coating material and the second coating material have different compositions.

20. The method for manufacturing the composite component according to claim 16, characterized in that, The compound containing the siloxane bond in the first coating material and / or the second coating material is at least one of organosilicon and silica sol.

21. The method for manufacturing the composite component according to claim 16, characterized in that, After at least one of the inner layer forming process and the outer layer forming process, there is an impregnation process for impregnating the matrix material containing the compound having siloxane bonds.

22. The method for manufacturing the composite component according to claim 16, characterized in that, It has a roughening process that roughens the substrate.

23. The method for manufacturing the composite component according to claim 16, characterized in that, The resin layer forming process includes: coating the outermost surface with a resin material containing a resin different from the resins contained in the first coating material and the second coating material, and then curing it.

24. An energy storage device, characterized in that, Multiple battery cells or battery modules are connected by a composite component as described in any one of claims 1 to 15.

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