Composite component

Abstract

Provided is a composite member which has excellent heat resistance and particularly excellent insulating properties, which does not require a winding operation such as a ceramic tape, does not cause winding irregularities or gaps, can easily cope with a complicated shape, and can maintain excellent insulating properties and heat resistance even when heated at a high temperature. A composite member (1) is provided with a base material (2) and an insulating film (3) that covers at least a part of the surface of the base material (2). The insulating film (3) is formed by alternately laminating a plurality of first films (11) and a plurality of second films (12) in this order from the base material (2) side. The first coating film (11) has a matrix (10) containing a compound having a siloxane bond, and an inorganic material (20) dispersed in the matrix (10). The second coating film is made of the material of the base body (10).

Description

Technical Field

[0001] This invention relates to composite components with an insulating coating on a substrate. Background Technology

[0002] To electrically connect 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 using busbars that serve as conductive members. Furthermore, lithium-ion secondary batteries, which offer higher capacity and output compared to lead-acid and nickel-metal hydride batteries, are primarily used in these battery cells.

[0003] In battery cells, overcurrent sometimes flows during charging and discharging, causing the busbars to heat up and, depending on the situation, sometimes even generate flames. Therefore, the busbars are required to have insulation and heat resistance. For example, Patent Document 1 describes a busbar with a ceramic strip, such as mica tape, wound around a copper busbar body as a fire-resistant layer.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Chinese Utility Model No. 216902355 Specification Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, Patent Document 1 requires the operation of winding the ceramic strip around the busbar body. Due to space constraints in the battery cell mounting area, the busbar sometimes has a complex shape. If 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, the possibility of the adhesive surface of the ceramic strip peeling off is also considered. Furthermore, a nylon strip is wound around the outside of the mica strip as an insulating layer, but the nylon strip has problems with heat resistance and will therefore break due to heat, failing to maintain the desired insulation.

[0009] Therefore, the object of the present invention is to provide a composite component that has excellent heat resistance and, in particular, excellent insulation, does not require the winding operation of ceramic tape, does not produce uneven winding or gaps, can easily handle complex shapes, and can maintain excellent insulation and heat resistance even when heated at high temperatures.

[0010] Methods for solving problems

[0011] The above-mentioned objective of the present invention is achieved by the following [1] configuration relating to the composite component.

[0012] [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 has the following characteristics: A first coating having a matrix comprising a compound having siloxane bonds and an inorganic material dispersed in said matrix; and The second coating is made of the material of the substrate. Multiple copies of the first coating and the second coating are alternately layered from the substrate side.

[0013] Furthermore, preferred embodiments of the present invention relating to composite components include the following [2] to

[14] .

[0014] [2] According to the composite component described in [1], the insulating coating has a thickness of 150 μm or more.

[0015] [3] The composite component according to [1] or [2] is characterized in that, When observing a cross-section of the insulating film in a direction parallel to the film thickness, Within any range of the first coating, the porosity P1 in a rectangular region R1 with the edge of the insulating coating in the film thickness direction set to 50 μm and the edge in the direction orthogonal to the film thickness direction set to 300 μm is less than 10%.

[0016] [4] The composite component according to any one of [1] to [3] is characterized in that at least a portion of the surface of the insulating coating has the second coating.

[0017] [5] The composite component according to [4] is characterized in that the thickness of the second coating, which exists in at least a portion of the surface of the insulating film, is more than 10 μm and less than 100 μm.

[0018] [6] The composite component according to any one of [1] to [5] is characterized in that at least a portion of the surface of the insulating coating has a resin layer comprising a resin different from the material of the substrate.

[0019] [7] The composite component according to [6] is characterized in that the thickness of the resin layer is more than 100 μm and less than 600 μm.

[0020] [8] The composite component according to any one of [1] to [7] is characterized in that the compound having siloxane bonds is at least one of organosilicon and silica sol.

[0021] [9] The composite component according to any one of [1] to [8] is characterized in that the inorganic material comprises at least one selected from silicon dioxide, alumina, mullite and zirconium oxide.

[0022]

[10] The composite component according to any one of [1] to [8] 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.

[0023]

[11] The composite component according to any one of [1] to [8] is characterized in that the inorganic material comprises at least one selected from flakes, fibers and granules.

[0024]

[12] The composite component according to any one of [1] to [8] is characterized in that the inorganic material comprises at least one of a sheet-like glassy material and mica.

[0025]

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

[12] is characterized in that it is applied to a busbar connecting a plurality of battery cells or battery modules.

[0026]

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

[12] is characterized in that it is applied to a connector, a protective component of a battery module, a housing of an electronic component, a battery cell, a battery module, a battery pack, or a coil of a motor.

[0027] Invention Effects

[0028] The composite component of the present invention exhibits excellent heat resistance and insulation properties because the insulating coating covering at least a portion of the substrate has a first coating, which comprises a matrix containing a compound having siloxane bonds and an inorganic material. Furthermore, since a plurality of the first coating and a second coating composed of the matrix material are alternately layered, the insulation properties are further improved, maintaining excellent insulation and heat resistance even when heated at high temperatures. Attached Figure Description

[0029] Figure 1 The accompanying drawing is a photograph showing a cross-section of the composite component according to this embodiment.

[0030] Figure 2 This is a perspective view showing the busbar of the composite component to which this embodiment is applied.

[0031] Figure 3A The diagram shows the manufacturing method of the composite component according to the process sequence, and the schematic diagram shows the situation after the first coating material curing process.

[0032] Figure 3B The diagram shows the manufacturing method of the composite component according to the process sequence, and the schematic diagram shows the situation after the first impregnation process.

[0033] Figure 3C The diagram shows the manufacturing method of the composite component according to the process sequence, and the schematic diagram shows the situation after the second curing process of the first coating material.

[0034] Figure 3D The diagram shows the manufacturing method of the composite component according to the process sequence, and the schematic diagram shows the situation after the resin layer formation process. Detailed Implementation

[0035] In order to obtain a composite component that solves the above-mentioned problems without using an insulating tape such as a ceramic tape, the inventors conducted in-depth research. As a result, they discovered that by coating the surface of a substrate with an insulating film, forming an insulating film covering the surface of the substrate, complex shapes can be easily accommodated.

[0036] Furthermore, the inventors conducted in-depth research to further improve the insulation properties of the insulating coating and found that alternatingly stacking multiple first and second coatings is effective. The first coating has a matrix containing a compound with siloxane bonds and an inorganic material, and the second coating is composed of the matrix material.

[0037] Hereinafter, embodiments of the present invention 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.

[0038] [Composite Components]

[0039] Figure 1 This is a photographic representation of a cross-section of the composite member according to this embodiment. The composite member 1 has a substrate 2 and an insulating film 3 covering at least a portion of the surface of the substrate 2. The insulating film 3 is formed by sequentially and alternately layering a plurality of first films 11 and second films 12 from the substrate 2 side. The first films 11 and second films 12 constituting the insulating film 3 of the composite member 1 of this embodiment, as well as the substrate 2, will be described in detail below.

[0040] <Insulating Coating>

[0041] like Figure 1 As shown, the insulating film 3 of the composite component 1 in this embodiment is alternately stacked with three layers each of the first film 11 and the second film 12 from the substrate 2 side.

[0042] (First coating)

[0043] The first coating 11 comprises a matrix 10 containing a compound having siloxane bonds and an inorganic material 20 dispersed in the matrix 10. Since both the compound having siloxane bonds and the inorganic material 20 are materials with excellent heat resistance and insulation, excellent heat resistance and insulation can be obtained when the first coating 11, constituting the insulating coating 3, includes both the compound having siloxane bonds and the inorganic material 20 as constituent components. Furthermore, a plurality of pores 30 are formed inside the first coating 11.

[0044] It should be noted that, as compounds containing siloxane bonds (Si-O-Si bonds), examples include organosilicon and silica sol (silicon dioxide: SiO2). Furthermore, from the viewpoint of excellent heat resistance and insulation, the compound containing siloxane bonds in the matrix 10 is preferably at least one of organosilicon and silica sol, more preferably organosilicon. Additionally, it is also preferred that the matrix 10 contains both organosilicon and silica sol.

[0045] (Thickness of the first coating)

[0046] The thickness of each of the first coatings 11 is not particularly limited. As shown in the manufacturing process described later, it is preferably a thickness that can be easily formed in a single coating when the coating liquid is applied to the substrate surface. The thickness of each of the first coatings 11 is preferably 50 μm or more, and more preferably 100 μm or more. On the other hand, if the thickness of the first coating 11 is too thick, it will be difficult to fill part of the pores formed in the manufacturing process with the second coating 12 during the process of forming the second coating 12, and the porosity described later may increase. Therefore, the thickness of each of the first coatings 11 is preferably 400 μm or less, and more preferably 300 μm or less.

[0047] (Porosity of the first coating)

[0048] like Figure 1As shown, pores 30 are formed in the first coating 11. However, according to the manufacturing method of the insulating coating 3, a large number of pores 30 may be generated inside the first coating 11, reducing the strength of the insulating coating 3. In this embodiment, it is preferable to control the porosity in any region R1 of the first coating 11 when observing a cross-section of the insulating coating 3 in the direction parallel to the film thickness. It should be noted that region R1 refers to a rectangular region in any region of the first coating 11, with the edge in the film thickness direction set to 50 μm and the edge in the direction orthogonal to the film thickness direction set to 300 μm. If the porosity P1 in region R1 is 10% or less, the overall number of pores 30 in the insulating coating 3 is reduced. As a result, the inorganic material 20 in the first coating 11 is almost filled with the substrate 10, and the first coating 11 becomes a dense structure, thus ensuring sufficient overall strength of the insulating coating 3. Therefore, the porosity P1 is preferably 10% or less, more preferably 8% or less, and even more preferably 6% or less.

[0049] In this embodiment, the porosity P1 is calculated using the method described below. First, a microscopic photograph is taken of a cross-section of the composite component 1 with the insulating coating 3 formed thereon, in a direction parallel to the thickness direction. Next, an arbitrary region R1 is selected from the obtained photograph, and the pores 30 present in region R1 are extracted, and the total area of ​​the pores 30 in region R1 is calculated. Then, the porosity P1 in region R1 can be calculated by dividing the total area of ​​the pores 30 by the area of ​​region R1. Regarding the porosity P1, it is preferable to obtain the average porosity by collecting samples from region R1 at three locations within the aforementioned range, and more preferably by calculating the average porosity from five locations within the aforementioned range.

[0050] (Second coating)

[0051] Unlike the first coating 11, the second coating 12 does not contain inorganic material 20, but is composed of the material of the substrate 10. Therefore, a high degree of adhesion is achieved between the first coating 11 and the second coating 12. Furthermore, the second coating 12 is a hard and dense layer, and the material containing the substrate of a compound with siloxane bonds exhibits excellent insulation properties; therefore, by stacking multiple second coatings 12, the insulation properties can be further improved. In this embodiment, it is preferable that the second coating 12 is present on at least a portion of the surface of the insulating coating 3. If the second coating 12 is present on the surface of the insulating coating 3, damage to the surface of the composite member 1 can be suppressed, or the impact of colliding objects can be mitigated. Additionally, by having the second coating 12 on the surface of the insulating coating 3, the effect of preventing the inorganic material 20 contained in the first coating 11 from detaching can also be achieved.

[0052] (Thickness of the second coating)

[0053] If the thickness of the second coating 12 existing on the surface of the insulating coating 3 is 10 μm or more, the second coating 12 can protect the composite member 1 and prevent the inorganic material 20 and the like from falling off within the first coating 11. Therefore, the thickness of the second coating 12 is preferably 10 μm or more. Furthermore, if the thickness of the second coating 12 is 100 μm or less, peeling can be suppressed. Therefore, the thickness of the second coating 12 is preferably 100 μm or less. It should be noted that, among the multiple stacked layers, if the thickness of the second coating other than the surface is 10 μm or more, the effect of improving insulation can be sufficiently obtained; if it is 100 μm or less, peeling can be suppressed. Therefore, the thickness of the second coating other than the surface is also preferably 10 μm or more. Furthermore, the thickness of the second coating other than the surface is preferably 100 μm or less.

[0054] (Thickness of the insulating coating)

[0055] If the thickness of the insulating film 3 is less than 150 μm, the strength of the insulating film 3 is insufficient, and peeling may occur, making it difficult to ensure insulation. Therefore, the thickness of the insulating film 3 is 150 μm or more, preferably 200 μm or more. On the other hand, since the strength of the insulating film 3 increases with the thickness of the insulating film 3 having the porosity described later, there is no particular upper limit on the film thickness. However, if the film thickness is too thick, it becomes difficult to control the dimensions of the composite component 1, and the manufacturing cost also increases. In addition, peeling is more likely to occur. Therefore, the thickness of the insulating film 3 is preferably 800 μm or less, more preferably 600 μm or less.

[0056] In the composite component 1 constructed as described above, instead of winding insulation onto the substrate 2, an insulating film 3 is formed by coating the surface of the substrate 2 with an insulating film that adheres tightly to the substrate 2. Therefore, when manufacturing the composite component 1 of this embodiment, no winding operation is required, and there are no problems such as uneven winding, gaps, or peeling, and complex shapes can be easily handled. In addition, since the first film 11 constituting the insulating film 3 has a matrix 10 containing a compound with siloxane bonds (Si-O-Si bonds) such as organosilicon or silica sol (silicon dioxide: SiO2) and an inorganic material 20, it is not prone to deterioration even when the composite component 1 is exposed to high temperatures, and can maintain excellent heat resistance and insulation. Furthermore, since a second film 12 with a dense structure composed of the material of the matrix 10 is repeatedly laminated, even better insulation can be obtained.

[0057] Hereinafter, the materials contained in the first film 11 and the second film 12 constituting the insulating film 3 in the composite component 1 of this embodiment will be described in further detail.

[0058] (Compounds containing siloxane bonds: organosilicon)

[0059] As a preferred example of a compound containing siloxane bonds in the substrate 10 of the insulating coating 3, the organosilicon is heated during the curing process of the coating material in the manufacturing method described later, thereby causing the functional groups to disappear and generating SiO bonds. Furthermore, if a fire or similar event occurs near the composite component and the insulating coating is heated to a temperature of, for example, 700°C or higher, SiO2 is generated through thermal decomposition. Since this SiO2 will not burn even when exposed to flame, the insulating coating 3 containing organosilicon can achieve excellent heat resistance. That is, even when the composite component 1 of this embodiment is heated at high temperatures, the insulating coating 3 will not peel off and will remain tightly bonded to the substrate 2, thereby maintaining excellent insulation and heat resistance. It should be noted that organosilicon can be either organosilicon resin or organosilicon rubber; however, from the viewpoint of achieving a high density of formed SiO2, organosilicon resin is preferred.

[0060] (Inorganic materials)

[0061] Because inorganic material 20 has a high melting point and excellent heat resistance, the overall heat resistance of the insulating film 3 can be improved by including inorganic material 20 in the first film 11 constituting the insulating film 3. In addition, inorganic material 20 can also act as a skeleton in the first film 11, thus improving the strength of the insulating film 3.

[0062] As the inorganic material 20, it preferably comprises a silicate compound. As described above, organosilicon, as an example of a compound having siloxane bonds, can be transformed into SiO2 through thermal decomposition, but the silicate compound has the same composition as the SiO2 formed by organosilicon, thus improving the bonding strength between the organosilicon-containing matrix 10 and the inorganic material 20. It should be noted that the silicate compound preferably comprises at least one selected from glassy materials, mica, kaolin, talc, clay, pyrophyllite, montmorillonite, bentonite, wollastonite, calcareous silica, zeolite, diatomaceous earth, and halloysite.

[0063] It should be noted that, as another preferred example of a compound having 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 10 having silica sol (silica) and the inorganic material 20.

[0064] Furthermore, the inorganic material 20 preferably includes at least one selected from silica, alumina, mullite, and zirconium oxide. Since these materials have high melting points and high insulation properties, including them in the first coating 11 further improves the heat resistance and insulation of the insulating coating 3 as a whole. It should be noted that, as an example of the composite component of the present invention, in the case of a busbar, the envisioned heat exposure temperature for the busbar is above the melting point of the metal material typically used in the busbar body. In this embodiment, if silica, alumina, mullite, zirconium oxide, etc., are included as the inorganic material 20, these materials have melting points above the aforementioned heat exposure temperature, thus preventing the busbar body from being exposed to high heat. Therefore, the above materials are suitable for use as materials for the insulating coating 3 in the busbar.

[0065] Furthermore, the inorganic material 20 preferably comprises at least one shape selected from flakes, fibers, and granules. If the inorganic material 20 has such a shape, the adhesion between the inorganic material 20 and the substrate 10 is increased when the inorganic material 20 is dispersed in the substrate 10, thereby improving the strength of the insulating coating 3.

[0066] Furthermore, when the inorganic material 20 includes a glass-based material, at least one selected from flake-shaped glass-based materials, glass particles, and glass fibers is preferably used as the glass-based material. The flake-shaped glass-based material exhibits excellent insulation and heat resistance due to its planar orientation within the insulating coating 3. Therefore, it is particularly preferred to include a flake-shaped glass-based material as the glass-based material. Additionally, for the same reasons as with flake-shaped glass-based materials, mica is particularly preferred as the inorganic material 20.

[0067] The content of inorganic material 20 in the first coating 11 relative to the total components 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 20 is less than 3% by volume, it may not be possible to obtain sufficient insulation and heat resistance. On the other hand, if it exceeds 70% by volume, the viscosity of the coating liquid used for impregnation coating becomes too high, resulting in poor film formation.

[0068] The content of inorganic material 20 in the first coating 11 can be determined, for example, by the same method as the porosity determination method described above. That is, a cross-section of the insulating coating 3 parallel to its thickness direction is photographed using an electron microscope. A predetermined area is selected from the obtained photograph, and the portion within that area that can be identified as inorganic material is colored. Then, the content (volume %) of inorganic material 20 can be calculated by dividing the total area of ​​the colored portion (inorganic material) by the area of ​​the selected area. A larger measurement area results in a smaller error. For example, similar to the porosity measurement area described above, a rectangular area can be selected with the thickness side of the first coating 11 set to 50 μm and the side perpendicular to the thickness direction set to 300 μm. Regarding the content of inorganic material 20 in the first coating 11, it is preferable to collect samples of the above-mentioned size from three different locations in the first coating 11 and calculate the average content. More preferably, the average content can be calculated from five different locations.

[0069] It should be noted that, in addition to the substrate 10 and inorganic material 20 described above, the first coating 11 constituting the insulating coating 3 may also contain other materials such as flame retardants, dispersants, and pigments, without affecting the insulation and heat resistance. Furthermore, as described later, the first coating 11 is formed by coating the surface of the substrate with a coating material (liquid coating), which serves as the first coating material. However, to improve the coating performance of the liquid coating containing the substrate 10 and inorganic material 20, it is preferable to include a thixotropic agent.

[0070] Similar to the first coating 11, the second coating 12 may also contain other materials such as flame retardants, dispersants, and pigments, without affecting the insulation and heat resistance.

[0071] <Resin Layer>

[0072] The composite component 1 may have a resin layer (not shown) on at least a portion of its surface, comprising a resin different from that of the matrix. Insulating resins can be used as the material for the resin layer, such as epoxy resin, nylon resin, SBR (styrene-butadiene rubber), silicone rubber, etc. Having a resin layer further improves the insulation and heat resistance of the composite component 1.

[0073] (Thickness of the resin layer)

[0074] When the composite component 1 has a resin layer, if the thickness of the resin layer is 100 μm or more, the effect of improving insulation and heat resistance can be sufficiently obtained. Therefore, 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 the increase in manufacturing cost can be suppressed. 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.

[0075] <Substrate>

[0076] In this embodiment, the substrate 2 is not particularly limited, and the main body portion of various articles of the composite component 1 applied in this embodiment can be used as the substrate 2. For example, when using the busbar described later as the composite component 1, a conductive busbar body can be used as the substrate 2. It should be noted that the busbar body is conductive, and the substrate itself is energized, but in this embodiment, 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.

[0077] [Specific Application Examples of Composite Components]

[0078] There are no particular limitations on the products using composite component 1; for example, it can be used in busbars in energy storage devices for connecting multiple battery cells or battery modules. The structure of composite component 1 will be described below using a busbar as an example.

[0079] Figure 2 This is a perspective view showing the generatrix of the composite component using this embodiment. It should be noted that... Figure 2 The diagram shows the busbar (composite component) 100 before it is installed on the battery cell 130. The busbar body (substrate) 110 is, for example, a Z-shaped metal plate component, fixed by inserting the electrode 135 of the battery cell 130 into a connection hole 115a at one end and covering it with a terminal cap 136. Additionally, a battery cell (not shown) and an external device (not shown) are connected to a connection hole 115b at the other end of the busbar body 110. Furthermore, the area of ​​the busbar body 110 other than the connection holes 115a and 115b is covered with an insulating film 3. This constitutes the busbar 100.

[0080] It should be noted that, although the illustration is omitted, the main body 110 of the busbar may be in the shape of an I-shape or have an irregular shape such as a bend, and can be made into various shapes depending on the location of the battery unit 130.

[0081] If the main body 110 of the busbar is shaped like a Z-shape with a bend 110a and a curved portion (not shown), the following problems arise. For example, as with the busbar shown in Patent Document 1 above, in the process of winding the ceramic strip around the main body, the winding operation is time-consuming in order to avoid uneven winding and gaps at the bend 110a and the curved portion. In addition, it is also conceivable that gaps may occur between the ceramic strips due to vibration or the adhesive between the ceramic strip and the main body may peel off.

[0082] In contrast, in the busbar 100 constructed as described above, instead of winding a strip onto the busbar body 110 to impart insulation, the surface of the busbar body 110 is alternately coated with the material of the first film 11 (first film material) and the material of the second film 12 (second film material) forming the insulating film 3 several times, forming an insulating film 3 that is tightly adhered to the busbar body 110. Therefore, when manufacturing the busbar 100, there is no need for winding operations, and there are no problems such as uneven winding, gaps, or peeling, and complex shapes can be easily handled.

[0083] It should be noted that, as a method for applying the first coating 11 to the surface of the busbar body 110 with the coating material, "immersion coating" in which the busbar body 110 is immersed in the coating liquid, or coating using a brush or spray can be used. In the case of immersion coating, since the insulating coating 3 is not formed in the connection holes 115a and 115b, the area is masked before immersion in the coating liquid. Furthermore, as a method for applying the coating liquid for the second coating 12 to the surface of the first coating 11, it is preferable to immerse the busbar body 110 with the first coating 11 in the coating liquid for the second coating 12 after masking the areas where the insulating coating 3 is not formed. By repeating this process multiple times, an insulating coating 3 covering at least a portion of the surface of the busbar body 110 can be formed.

[0084] In addition to the busbar described above, the composite component of this embodiment can also be applied to connectors, protective components of battery modules, housings of electronic components, battery cells, battery modules, battery packs, or motor coils.

[0085] [Manufacturing Method of Composite Components]

[0086] The composite component of this embodiment can be manufactured, for example, by the manufacturing method shown below. Figures 3A to 3D This is a schematic diagram illustrating the manufacturing method of the composite component according to the sequence of processes described in this embodiment. Figures 3A to 3D In the middle, regarding the above Figure 1 The same parts shown are marked with the same symbols, and their detailed descriptions are omitted or simplified. However, in Figures 3A to 3DFor ease of explanation, the symbols for the first coating of the first layer and the first coating of the third layer are distinguished by counting the layers in the order of stacking from the substrate 2. Similarly, the symbols for the second coating of the second layer and the second coating of the fourth layer are also distinguished. It should be noted that in the following manufacturing method, the case where the compound containing siloxane bonds in the substrate 10 is organosilicon is described, but the case where the compound containing siloxane bonds is silica sol (silica) can also be applied.

[0087] <The Formation of the First Layer>

[0088] (Coating process: First time)

[0089] like Figure 3A As shown, firstly, a material for the first coating 11a (first coating material) is coated onto at least a portion of the surface of the substrate 2. The first coating material is, for example, a material containing an organosilicon matrix 10 and an inorganic material 20 added to an organic solvent.

[0090] (First drying process for coating material: first step)

[0091] After the above coating process, the first coating material is dried, for example, at a temperature of 50°C. During the drying process of the first coating material, the organic solvent is evaporated.

[0092] (First curing process for the coating material: First step)

[0093] Then, the dried first coating material is heated at a temperature of, for example, 200°C, to cure it. Through this curing process of the first coating material, the organosilicon undergoes dehydration and condensation to form a first coating 11a with a three-dimensional network structure. At this time, a plurality of pores 30 are formed in the first coating 11a.

[0094] <The Formation of the Second Layer>

[0095] (Immersion process: First time)

[0096] Then, the substrate 2 with the first coating 11a is immersed in a material for the second coating 12a (the second coating material). The second coating material does not contain inorganic material 20 and is formed by adding a material containing organosilicon matrix 10 to an organic solvent. Figure 3B As shown, through this impregnation process, a portion of the plurality of pores 30 formed in the first coating 11a is filled with the second coating material, thereby reducing the porosity of the first coating 11a. Additionally, the remaining second coating material not absorbed by the pores 30 remains on the surface of the first coating 11a. Then, the second coating material is dried at, for example, a temperature of 50°C, and then heated at, for example, a temperature of 200°C to cure it. Thus, a second coating 12a composed of a material containing a silicone matrix 10 is formed on the surface of the first coating 11a.

[0097] <The Formation of the Third Layer>

[0098] (Coating process: Second time)

[0099] Then, as Figure 3C As shown, the first coating material is laminated again on the surface of the second coating 12a. This first coating material is the same material used in the first coating process described above.

[0100] (First coating material drying process: Second time)

[0101] After the second coating process described above, the first coating material is dried, for example, at a temperature of 50°C. This second drying process of the first coating material causes the organic solvents in the first coating material applied in the second coating process to evaporate.

[0102] (First coating material curing process: Second time)

[0103] Then, the dried first coating material is heated at a temperature of, for example, 200°C to cure it. Through this second curing process of the first coating material, the organosilicon undergoes dehydration and condensation, forming a three-dimensional network structure of the first coating 11b. At this time, a plurality of pores 30 are formed in the first coating 11b.

[0104] <The Formation of the Fourth Layer>

[0105] (Immersion process: Second time)

[0106] Then, as Figure 3D As shown, a substrate 2 with a first coating 11b is immersed in a second coating material. The second coating material is the same material used in the first immersion process described above. Through this second immersion process, the second coating material fills a portion of the plurality of pores 30 formed in the first coating 11b, reducing the porosity of the first coating 11b. Additionally, the second coating material not absorbed by the pores 30 remains on the surface of the first coating 11b. Then, the second coating material is dried at, for example, a temperature of 50°C, and then heated at, for example, a temperature of 200°C to cure it. Thus, a second coating 12b composed of a material containing a silicone matrix 10 is formed on the surface of the first coating 11b.

[0107] It should be noted that the impregnation time in the first and second impregnation processes is not particularly limited, as long as the impregnation time is chosen such that the remaining second coating material remains on the surface of the first coatings 11a and 11b, forming the second coatings 12a and 12b. These second coatings 12a and 12b are composed of the remaining second coating material on the surface, and therefore have a dense structure that does not contain inorganic material 20.

[0108] (Resin layer formation process)

[0109] Then, an epoxy resin coating is applied to the second coating 12b, for example, by electrostatic powder coating or flow impregnation coating, to form a resin layer 7. In the case of forming the resin layer 7, a portion of the material constituting the resin layer 7 can penetrate into the interior of the underlying layer.

[0110] As described above, the second coating material used in the impregnation process is an inorganic material 20 that does not contain the first coating material used in the impregnation process. In addition, since the material of the substrate 10 is silicone, by including silicone in the second coating material, the silicone content is increased, and the SiO2 content is also increased, so the insulating coating 3 can be maintained more effectively even when exposed to flame.

[0111] It should be noted that in the above manufacturing method, the series of steps from coating to impregnation is repeated twice, but it can also be repeated multiple times until the desired film thickness is achieved. Even when the series of steps is repeated more than three times, since the impregnation step of impregnating the second coating material is included after the formation of the first coating, the first coating and the second coating are repeatedly stacked, and an insulating coating 3 with high insulation properties can be formed.

[0112] 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 readily occur to those skilled in the art within the scope of the claims, and these modifications naturally 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 present invention.

[0113] It should be noted that this application is based on Japanese patent application filed on September 29, 2023 (Japanese Patent Application No. 2023-170683), the contents of which are incorporated herein by reference.

[0114] Symbol Explanation

[0115] 1. Composite components

[0116] 2. Substrate

[0117] 3. Insulating film

[0118] 7 Resin Layer

[0119] 10 Matrix

[0120] 11,11a,11b First coating

[0121] 12, 12a, 12b Second coating

[0122] 20 Inorganic Materials

[0123] 30 pores

[0124] 100 busbar

[0125] 110 Busbar Main Body

[0126] 115a and 115b connecting holes

[0127] 130 battery cells

[0128] 135 electrode

[0129] 136 terminal cap

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 has the following characteristics: The first coating has a matrix comprising a compound having siloxane bonds and an inorganic material dispersed in the matrix; and The second coating is made of the material of the substrate. Multiple copies of the first coating and the second coating are alternately layered from the substrate side.

2. The composite component according to claim 1, characterized in that, The thickness of the insulating coating is 150 μm or more.

3. The composite component according to claim 1, characterized in that, When observing a cross-section of the insulating film in a direction parallel to the film thickness, Within any range of the first coating, the porosity P1 in a rectangular region R1 with the edge of the insulating coating in the film thickness direction set to 50 μm and the edge in the direction orthogonal to the film thickness direction set to 300 μm is less than 10%.

4. The composite component according to claim 1, characterized in that, The second coating is present on at least a portion of the surface of the insulating coating.

5. The composite component according to claim 4, characterized in that, The thickness of the second coating, which exists on at least a portion of the surface of the insulating film, is more than 10 μm and less than 100 μm.

6. The composite component according to any one of claims 1 to 5, characterized in that, At least a portion of the surface of the insulating coating has a resin layer comprising a resin different from that of the substrate.

7. The composite component according to claim 6, characterized in that, The thickness of the resin layer is between 100 μm and 600 μm.

8. The composite component according to any one of claims 1 to 5, characterized in that, The compound having siloxane bonds is at least one of organosilicon and silica sol.

9. The composite component according to any one of claims 1 to 5, characterized in that, The inorganic material comprises at least one selected from silicon dioxide, alumina, mullite, and zirconium oxide.

10. The composite component according to any one of claims 1 to 5, 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.

11. The composite component according to any one of claims 1 to 5, characterized in that, The inorganic material comprises at least one selected from flakes, fibers, and granules.

12. The composite component according to any one of claims 1 to 5, characterized in that, The inorganic material comprises at least one of a sheet-like glassy material and mica.

13. The composite component according to any one of claims 1 to 5, characterized in that, Used for busbars that connect multiple battery cells or battery modules.

14. The composite component according to any one of claims 1 to 5, characterized in that, Used in connectors, protective components for battery modules, housings for electronic components, battery cells, battery modules, battery packs, or motor coils.

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