Wear-resistant composite mica tape and preparation method and application thereof

Abstract

The present application relates to a kind of wear-resistant composite mica tape and its preparation method and application, the wear-resistant composite mica tape includes the first reinforcing layer, first adhesive layer, mica layer, second adhesive layer and second reinforcing layer arranged in sequence;The first reinforcing layer includes glass fiber cloth, and the second reinforcing layer includes wear-resistant fiber cloth.The present application solves the problems of insufficient wear resistance, poor flexibility, pollution and other problems existing in the application of existing mica tape in new energy battery pack thermal runaway protection, and simultaneously realizes the differentiated customization of product performance through the replaceable design of various wear-resistant fiber cloth substrates.

Description

Technical Field

[0001] This invention relates to the field of electrical insulation and thermal protection materials, and in particular to a wear-resistant composite mica tape, its preparation method, and its application. Background Technology

[0002] The rapid development of new energy vehicles has placed higher demands on the safety performance of power batteries. When a battery pack experiences thermal runaway, high temperatures (>800°C), high-pressure airflow, and splashing molten material are instantly generated inside the cells, triggering a chain reaction of combustion and seriously threatening the safety of occupants.

[0003] Due to its excellent high-temperature resistance and insulation properties, mica can significantly suppress heat diffusion during thermal runaway events in battery packs and has been successfully applied in electric vehicle power batteries and energy storage battery systems. Mica tape is widely used in the high-temperature insulation protection of wire harnesses and copper busbars. Traditional fire-resistant mica tape typically uses a double-sided fiberglass structure of "fiberglass cloth / mica paper" or "fiberglass cloth / mica paper / fiberglass cloth" (such as "three-in-one mica tape"). This mica tape can be attached to components by wrapping or applying adhesive backing. The following shortcomings exist in this type of structure: (1) Poor abrasion resistance: The surface hardness of the fiberglass cloth is high but its abrasion resistance is insufficient. During the wrapping operation and under the long-term vibration environment of automobiles, the yarn is prone to slippage, fuzzing and wear, which leads to a weakening or even failure of the overall protective layer effect; it cannot meet the automotive grade requirements of D or more than 1000 abrasion resistance in ISO 6722 "Dimensions, test methods and requirements for 60V and 600V single core wires for road vehicles" and AK LV 312 "Technical Specifications and Test Methods for Adhesive Tapes for Automotive Wiring Harnesses"; (2) Insufficient flexibility: Pure fiberglass cloth has low elongation. When wrapping the battery harness or busbar curved or sharp corner structure area, mica paper is prone to cracking and glass fiber is prone to breakage, resulting in poor operability. (3) Weak adaptability to working conditions: The installation space inside the battery pack is limited. During assembly, conventional mica tape is prone to mica layer shedding or glass fiber flying, which affects the assembly environment in the workshop and the cleanliness inside the battery, causing certain health hazards to operators. In addition, it will continue to wear out during long-term operation, and the pollutants generated may lead to battery safety risks.

[0004] Existing polyester film-reinforced mica tape is also used, which can effectively solve the problem of surface cleanliness. However, its high rigidity cannot meet the operational requirements of wrapping wire harnesses, resulting in many limitations in its application.

[0005] Therefore, there is an urgent need to provide a composite mica tape that combines high temperature resistance, wear resistance, lightweight and good flexibility to meet the engineering requirements for thermal runaway safety protection of new energy battery packs. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a wear-resistant composite mica tape, comprising a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer comprises glass fiber cloth, and the second reinforcing layer comprises wear-resistant fiber cloth. This invention solves the problems of insufficient wear resistance, poor flexibility, and contamination in existing mica tapes used for thermal runaway protection in new energy battery packs. Furthermore, through a replaceable design of various wear-resistant fiber cloth substrates, a composite mica tape that balances high-temperature resistance, wear resistance, lightweight, and good flexibility is obtained.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a wear-resistant composite mica tape, the wear-resistant composite mica tape comprising a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer and a second reinforcing layer stacked sequentially. The first reinforcing layer comprises glass fiber cloth, and the second reinforcing layer comprises abrasion-resistant fiber cloth.

[0008] The wear-resistant composite mica tape of this invention uses fiberglass cloth as the inner reinforcing layer, which is the skeleton layer and provides high-temperature structural support. The open structure gives the mica layer sufficient air permeability and resin penetration channels, while reducing the mass per unit area. The mica layer, as the core fireproof and heat-insulating layer, has excellent high-temperature resistance and heat insulation performance. The wear-resistant fiber cloth, as the outer functional layer, can be flexibly selected according to the actual use scenario, achieving a flexible balance between flame retardancy, temperature resistance, flexibility and cost, and is suitable for customized needs of differentiated products.

[0009] As a preferred technical solution of the present invention, the mica layer includes any one of natural white mica paper, natural phlogopite paper, or synthetic mica paper.

[0010] Preferably, the wear-resistant fiber cloth includes any one of PET fiber cloth, PA fiber cloth, aramid fiber cloth, or blended fiber cloth.

[0011] Preferably, the blended fiber fabric comprises a combination of at least two of PET fiber fabric, PA fiber fabric, aramid fiber fabric, or chopped glass fiber, wherein typical but non-limiting combinations include: a combination of PET fiber fabric and PA fiber fabric, a combination of PET fiber fabric and aramid fiber fabric, a combination of PET fiber fabric and chopped glass fiber, a combination of PA fiber fabric and aramid fiber fabric, a combination of PA fiber fabric and chopped glass fiber, and a combination of aramid fiber fabric and chopped glass fiber.

[0012] Abrasion-resistant fiber cloths can be flexibly selected according to actual application scenarios. Among them, PET fiber cloth: high cost performance, abrasion resistance level up to D, suitable for cost-sensitive battery pack solutions; PA fiber cloth (nylon PA6 / PA66): abrasion resistance level up to D, better than PET, excellent flexibility, suitable for scenarios with complex curved surfaces and frequent friction during installation and operation; aramid fiber cloth (meta- / para-Aramid): naturally flame retardant (LOI≥28%), high heat resistance, suitable for scenarios with high heat flux density or strict flame retardancy requirements; blended fiber cloth (two or more combinations of PET / PA / aramid / glass fiber chopped strands): by adjusting the blending ratio, a flexible balance can be achieved between abrasion resistance, flame retardancy, temperature resistance, flexibility and cost, suitable for customized needs of differentiated products.

[0013] As a preferred technical solution of the present invention, the materials of the first adhesive layer and the second adhesive layer each independently include any one of high-temperature modified silicone resin adhesive, acrylic adhesive or double-sided tape.

[0014] Preferably, the high-temperature resistant modified silicone resin adhesive has a temperature resistance of ≥200℃, such as 200℃, 210℃, 220℃, 230℃, 240℃ or 250℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0015] In this invention, the silicone resin adhesive is a high-temperature resistant modified silicone resin adhesive.

[0016] Preferably, the acrylic adhesive has a temperature resistance of ≥100℃, such as 100℃, 110℃, 120℃, 130℃, or 140℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0017] In this invention, the acrylate adhesive includes (meth)acrylate polymer adhesives, which are prepared by copolymerization of one or more of acrylate monomers and methacrylate monomers; wherein the methacrylate monomers include methyl methacrylate and alkyl methacrylate homologues.

[0018] As a preferred technical solution of the present invention, the thickness of the mica layer is 0.15-0.25mm, for example, it can be 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.2mm, 0.21mm, 0.22mm, 0.23mm, 0.24mm or 0.25mm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0019] Preferably, the thickness of the first reinforcing layer is 0.02-0.06 mm, for example, it can be 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, 0.05 mm, 0.055 mm or 0.06 mm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0020] Preferably, the thickness of the second reinforcing layer is 0.13-0.25 mm, for example, it can be 0.13 mm, 0.15 mm, 0.18 mm, 0.20 mm, 0.22 mm or 0.25 mm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] Preferably, the areal density of the mica layer is 150-200 g / m³. 2 For example, it could be 150g / m 2 160g / m 2 170g / m 2 180g / m 2 190g / m 2 Or 200g / m 2 However, this does not limit the listed values; other unlisted values ​​within this range also apply.

[0022] Preferably, the areal density of the first reinforcing layer is 10-50 g / m³. 2 For example, it could be 10g / m 2 15g / m 2 20g / m 2 24g / m 2 25g / m 2 30g / m 2 35g / m 2 40g / m 2 45g / m 2 Or 50g / m 2 However, this does not limit the listed values; other unlisted values ​​within this range also apply.

[0023] Preferably, the areal density of the second reinforcing layer is 100-150 g / m³. 2 For example, it could be 100g / m 2 110g / m 2 120g / m 2 130g / m 2 140g / m 2 Or 150g / m 2 However, this does not limit the listed values; other unlisted values ​​within this range also apply.

[0024] In a second aspect, the present invention provides a method for preparing the wear-resistant composite mica tape described in the first aspect, the method comprising the following steps: (1) The first reinforcing layer is bonded to the mica layer through the first adhesive layer, and then subjected to the first rolling and first curing processes in sequence to obtain the composite mica tape semi-finished product; (2) The side of the mica layer away from the first adhesive layer is bonded to the second reinforcing layer through the second adhesive layer, and then subjected to the second rolling and second curing treatments in sequence to obtain the wear-resistant composite mica tape.

[0025] In this invention, a two-step wet roll forming composite process of "glass fiber first, then wear-resistant layer" is used to prepare wear-resistant composite mica tape.

[0026] In this invention, the wear-resistant composite mica tape is wound onto a paper core to obtain a finished product of core-wound composite mica tape, wherein the inner diameter of the paper core is 76mm.

[0027] As a preferred embodiment of the present invention, the coating amount of the first adhesive layer is 50-70 g / m². 2 For example, it could be 50g / m 2 55g / m 2 60g / m 2 65g / m 2 Or 70g / m 2 However, this does not limit the listed values; other unlisted values ​​within this range also apply.

[0028] Preferably, the coating amount of the second adhesive layer is 50-70 g / m². 2 For example, it could be 50g / m 2 55g / m 2 60g / m 2 65g / m 2 Or 70g / m 2 However, this does not limit the listed values; other unlisted values ​​within this range also apply.

[0029] As a preferred technical solution of the present invention, the linear pressure of the first roller is 3-10 N / mm, for example, it can be 3 N / mm, 4 N / mm, 5 N / mm, 6 N / mm, 7 N / mm, 8 N / mm, 9 N / mm or 10 N / mm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0030] Preferably, the linear pressure of the second roller is 3-10 N / mm, for example, it can be 3 N / mm, 4 N / mm, 5 N / mm, 6 N / mm, 7 N / mm, 8 N / mm, 9 N / mm or 10 N / mm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] As a preferred technical solution of the present invention, the temperature of the first curing treatment is 110-150℃, for example, it can be 110℃, 120℃, 130℃, 140℃ or 150℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0032] Preferably, the curing time of the first curing process is 2-5 minutes, for example, 2 minutes, 3 minutes, 4 minutes or 5 minutes, but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0033] As a preferred technical solution of the present invention, the temperature of the second curing treatment is 110-150℃, for example, it can be 110℃, 120℃, 130℃, 140℃ or 150℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0034] Preferably, the curing time for the second curing process is 3-8 minutes, for example, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes or 8 minutes, but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0035] In this invention, uniform bonding between layers is achieved by controlling the amount of adhesive applied and the curing temperature.

[0036] Thirdly, the present invention provides an application of the composite mica strip described in the first aspect in passive protection against thermal runaway in new energy battery packs.

[0037] The wear-resistant composite mica tape of the present invention is wrapped with wear-resistant fiber cloth outwards around the battery busbar, wire harness or backing adhesive and then attached to the surface of the module and top cover to achieve a synergistic effect of wear resistance, high temperature resistance and flame retardancy.

[0038] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The wear resistance of the wear-resistant composite mica tape described in this invention is significantly improved: the wear resistance test of the AK LV 312 automotive wiring harness tape with the outer wear-resistant fiber cloth (PET / PA / aramid / blended) is ≥1000 times, which is more than 10 times higher than that of pure glass fiber cloth. (2) Excellent flexibility: The pore structure of the fiberglass cloth and the elastic elongation of the wear-resistant fiber cloth work together to allow the composite mica tape to be tightly attached to irregular busbars or wire harnesses. (3) The wear-resistant composite mica tape of the present invention retains heat insulation and flame retardant properties, the mica layer continues to perform the function of high-temperature insulation and barrier, and the aramid fiber cloth does not need additional flame retardant finishing to meet UL94 V-0. Preferably, the PET / PA type achieves LOI (Limited Oxygen Index) ≥25% through flame retardant post-treatment; (4) The wear-resistant composite mica tape of the present invention has a variety of substrate options to suit different scenarios: PET fiber cloth has a wear resistance of ≥1100 times, PA fiber cloth has a wear resistance of ≥1800 times; aramid fiber cloth has natural flame retardancy (LOI≥28%) and excellent high temperature resistance; blended fabrics can be customized according to proportions. (5) The wear-resistant composite mica tape of the present invention has a functional zoning design: the inner skeleton of the glass fiber cloth is supported and the outer side of the wear-resistant fiber cloth is protected. The two materials complement each other and there is no risk of contamination by glass fiber and mica debris. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the cross-sectional structure of the composite mica tape of the present invention; Figure 2 This is a schematic diagram of the winding shape of the composite mica tape of the present invention; Wherein, 1-first reinforcing layer; 2-first adhesive layer; 3-mica layer; 4-second adhesive layer; 5-second reinforcing layer; 6-composite mica tape; 7-busbar or test steel bar. Detailed Implementation

[0040] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0041] Please see Figure 1 This invention provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially.

[0042] Table 1 shows the procurement information of the raw materials involved in the specific implementation method.

[0043] Table 1 Example 1 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural phlogopite paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2 The second reinforcing layer is PET plain weave fabric: 0.18mm thick, with a surface density of 120g / m³. 2The first adhesive layer and the second adhesive layer are each independently a high-temperature resistant modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above wear-resistant composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the natural phlogopite paper with silicone resin solution, and the coating amount is 60g / m. 2 The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the surface of the natural phlogopite paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with PET plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ drying tunnel for 5 minutes to obtain wear-resistant composite mica tape.

[0044] Example 2 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW40 plain weave fabric with a thickness of 0.04 mm and an areal density of approximately 32 g / m³. 2 The mica layer is a synthetic mica paper: fluorophlogopite, with a thickness of 0.18 mm and an areal density of 160 g / m³. 2 The second reinforcing layer is PET plain weave fabric: 0.18mm thick, with a surface density of 120g / m³. 2 The first adhesive layer and the second adhesive layer are each independently a high-temperature resistant modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above wear-resistant composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the synthetic mica paper with silicone resin solution, and the coating amount is 60g / m. 2 The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the other surface of the synthetic mica paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with PET plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ drying tunnel for 5 minutes to obtain wear-resistant composite mica tape.

[0045] Example 3 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural white mica paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2 The second reinforcing layer is PET plain weave fabric: 0.22mm thick, with a surface density of 135g / m³. 2 The first adhesive layer and the second adhesive layer are each independently a high-temperature resistant modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the natural mica paper with silicone resin solution, and the coating amount is 60g / m. 2 The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the surface of the natural mica paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with PET plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ drying tunnel for 5 minutes to obtain wear-resistant composite mica tape.

[0046] Example 4 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural phlogopite paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2 The second reinforcing layer is PA66 plain weave fabric: 0.2mm thick, with a surface density of 130g / m². 2 The first adhesive layer and the second adhesive layer are each independently a high-temperature resistant modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above wear-resistant composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the natural phlogopite paper with silicone resin solution, and the coating amount is 60g / m. 2The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the surface of the natural phlogopite paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with PA66 plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ oven for 5 minutes to obtain wear-resistant composite mica tape.

[0047] Example 5 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is a synthetic mica paper with a thickness of 0.18 mm and a surface density of 160 g / m³. 2 The second reinforcing layer is a meta-aramid plain weave fabric with a thickness of 0.18 mm and an areal density of 115 g / m³. 2 The first adhesive layer and the second adhesive layer are each independently a high-temperature resistant modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above wear-resistant composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the synthetic mica paper with silicone resin solution, and the coating amount is 60g / m. 2 The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the other surface of the synthetic mica paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with meta-aramid plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ drying tunnel for 5 minutes to obtain wear-resistant composite mica tape.

[0048] Example 6 This embodiment provides a composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural phlogopite paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2The second reinforcing layer is a PET / PA66 blended plain weave fabric (mass ratio 60 / 40, thickness 0.20mm, areal density 125g / m³). 2 The first adhesive layer and the second adhesive layer are each independently a high-temperature modified silicone resin liquid with a solid content of 35% and a temperature resistance rating of 220℃. The preparation method of the above composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the natural phlogopite paper with silicone resin solution, and the coating amount is 60g / m. 2 The first roll pressing is carried out with a linear pressure of 5 N / mm, and the first curing treatment is carried out in a 130℃ drying tunnel for 3 minutes to obtain glass fiber / mica semi-finished product. (2) Coat the surface of the natural phlogopite paper away from the glass fiber cloth and silicone resin solution with silicone resin solution evenly, with a coating amount of 60g / m². 2 It is combined with PET / PA66 blended plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 130℃ drying tunnel for 5 minutes to obtain composite mica tape.

[0049] Example 7 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural white mica paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2 The second reinforcing layer is PET plain weave fabric: 0.22mm thick, with a surface density of 135g / m³. 2 The first adhesive layer and the second adhesive layer are each independently KL-480 acrylic pressure-sensitive adhesive with a temperature resistance rating of 120℃. The preparation method of the above composite mica tape includes the following steps: (1) The glass fiber cloth is bonded to one side of the natural mica paper with an acrylic adhesive, and the coating amount is 50g / m. 2 The first roll pressing is carried out with a linear pressure of 3 N / mm, and the first curing treatment is carried out in a 150℃ drying tunnel for 2 minutes to obtain glass fiber / mica semi-finished product. (2) Apply acrylic adhesive evenly to the surface of the natural mica paper away from the fiberglass cloth, with a coating amount of 70 g / m². 2 It is combined with PET plain weave fabric, subjected to a second roll pressing, and then subjected to a second curing treatment in a 110℃ drying tunnel for 8 minutes to obtain wear-resistant composite mica tape.

[0050] Example 8 This embodiment provides a wear-resistant composite mica tape, which includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer is made of EW30 plain weave fabric with a thickness of 0.03 mm and an areal density of approximately 24 g / m³. 2 The mica layer is natural white mica paper: 0.20 mm thick, with a surface density of approximately 180 g / m³. 2 The second reinforcing layer is PET plain weave fabric: 0.22mm thick, with a surface density of 135g / m³. 2 The first and second adhesive layers are each independently double-sided adhesive tape 3M9448A, with a thickness of 50μm and a strength of 62g / m³. 2 Its temperature resistance rating is 100℃; The preparation method of the above composite mica tape includes the following steps: (1) The glass fiber cloth and natural white mica paper are bonded together with 3M 9448A double-sided tape and subjected to the first roll pressing. The linear pressure of the first roll pressing is 10N / mm to obtain the glass fiber / mica semi-finished product. (2) The other side of the natural white mica paper away from the glass fiber cloth is bonded to the PET plain weave cloth with 3M 9448A double-sided tape and then rolled for a second time to obtain wear-resistant composite mica tape.

[0051] Example 9 This embodiment provides a composite mica tape and its preparation method. The difference between this embodiment and Embodiment 1 is that, except that the second curing temperature is 90°C, everything else is the same as in Embodiment 1.

[0052] Example 10 This embodiment provides a composite mica tape and its preparation method. The difference between this embodiment and Embodiment 1 is that, except that the second curing temperature is 170°C, everything else is the same as in Embodiment 1.

[0053] Example 11 This embodiment provides a composite mica tape and its preparation method. The difference from Embodiment 1 is that, except that the coating amount of the second adhesive layer is 40 g / m², the composite mica tape is prepared using this method. 2 Except for the above, everything else is the same as in Example 1.

[0054] Example 12 This embodiment provides a composite mica tape and its preparation method. The difference from Embodiment 1 is that, except that the coating amount of the second adhesive layer is 80 g / m², the composite mica tape is prepared using this method. 2 Except for the above, everything else is the same as in Example 1.

[0055] Comparative Example 1 This comparative example provides a traditional three-in-one structure of "glass fiber cloth / phlogopite paper / glass fiber cloth". The specifications of each layer are the same as those of Example 1 in terms of areal density and thickness. The difference from Example 1 is that the second reinforcing layer is replaced with glass fiber cloth. All other aspects are the same as those of Example 1.

[0056] Comparative Example 2 This comparative example provides a three-in-one structure of "glass fiber cloth / phlogopite paper / PET film", which differs from Example 1 in that the second reinforcing layer is replaced with a 0.2mm thick, 275g / m³ structure. 2 The PET film is the same as in Example 1.

[0057] Test methods: The composite mica tapes prepared in Examples 1-12 and Comparative Examples 1-2 were cut into 25mm wide strips for later use. The overall thickness was measured according to the test method of GB / T 1040; the mass per unit area was measured by weighing method; the abrasion resistance of the automotive wiring harness tape was measured by fixing the composite mica tape to a 5mm diameter steel rod according to AK LV 312 standard; flexibility test: the composite mica tape was wound around a steel rod or battery busbar, and the winding pattern is shown in the diagram. Figure 2 As shown, observe whether there is cracking. The diameter of the winding rod in Examples 1, 2, and 4-12 is 10mm. Example 3 is used for battery busbar winding. Flexibility considerations: The smaller the diameter of the winding rod, the greater the process difficulty. The flexibility requirements of mica tape for battery busbar winding are significantly higher. Based on the process difficulty, the flexibility is divided into "optimal", "good", "good" and "poor". "Optimal" is used for battery busbar winding, with excellent fit to curved surfaces, no curling edges after winding, and no cracking at stress concentration points; "good" is no cracking with a winding rod diameter of 10mm; "good" is no cracking with a winding rod diameter ≥15mm; "poor" is breakage of surface glass fiber yarns with a winding rod diameter ≤25mm. In this invention, when the flexibility level of the wear-resistant composite mica tape is "optimal" or "excellent", it can meet the application requirements of passive protection scenarios for thermal runaway of new energy power battery packs.

[0058] The test results are shown in Table 2.

[0059] Table 2 The test results show that: (1) As can be seen from Examples 1 to 8, the present invention obtains a composite mica tape that combines high temperature resistance, wear resistance, lightweight and good flexibility by setting glass fiber cloth, first adhesive layer, mica layer, second adhesive layer and wear-resistant fiber cloth in sequence, with a unit area mass ≤480g / m 2The automotive wiring harness tape has an abrasion resistance of ≥1200 times. When the flexibility is "optimal", it is used for battery busbar wrapping. It has excellent adhesion to curved surfaces, no curling after wrapping, and no cracking at stress concentration points. When the flexibility is "excellent", the winding rod diameter is 10mm and there is no cracking. When the flexibility is "good", the winding rod diameter is ≥15mm and there is no cracking.

[0060] (2) As can be seen from Examples 1 to 9-12, the present invention can achieve uniform bonding between layers by further controlling the coating amount and curing temperature.

[0061] (3) As can be seen from Example 1 and Comparative Example 1, when the traditional “glass fiber cloth / phlogopite paper / glass fiber cloth” three-in-one structure is adopted, the number of abrasion resistance tests of the automotive wiring harness tape is 90 (only 7.5% of that in Example 1), and the surface glass fiber yarn breaks when the diameter of the winding rod is ≤25 mm. It cannot achieve the technical effect of high temperature resistance, abrasion resistance, lightweight and good flexibility.

[0062] (4) As can be seen from Example 1 and Comparative Example 2, when the three-in-one structure of "glass fiber cloth / phlogopite paper / PET film" is adopted, the number of wear resistance increases, but the mass per unit area increases significantly. Moreover, its rigidity is too strong to meet the operation requirements of wrapping wire harness. It cannot achieve the technical effect of taking into account high temperature resistance, wear resistance, lightweight and good flexibility.

[0063] In summary, the present invention obtains a composite mica tape that combines high temperature resistance, wear resistance, lightweight and good flexibility by setting glass fiber cloth, first adhesive layer, mica layer, second adhesive layer and wear-resistant fiber cloth in sequence.

[0064] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A wear-resistant composite mica tape, characterized in that, The wear-resistant composite mica tape includes a first reinforcing layer, a first adhesive layer, a mica layer, a second adhesive layer, and a second reinforcing layer stacked sequentially. The first reinforcing layer comprises glass fiber cloth, and the second reinforcing layer comprises abrasion-resistant fiber cloth.

2. The wear-resistant composite mica tape according to claim 1, characterized in that, The mica layer includes any one of natural white mica paper, natural phlogopite paper, or synthetic mica paper. Preferably, the wear-resistant fiber cloth includes any one of PET fiber cloth, PA fiber cloth, aramid fiber cloth, or blended fiber cloth; Preferably, the blended fiber fabric includes a combination of at least two of PET fiber fabric, PA fiber fabric, aramid fiber fabric, or chopped glass fiber.

3. The wear-resistant composite mica tape according to claim 1 or 2, characterized in that, The materials of the first adhesive layer and the second adhesive layer each independently include any one of high-temperature modified silicone resin adhesive, acrylic adhesive, or double-sided adhesive tape; Preferably, the high-temperature modified silicone resin adhesive has a temperature resistance of ≥200℃; Preferably, the acrylate adhesive has a temperature resistance of ≥100℃.

4. The wear-resistant composite mica tape according to any one of claims 1-3, characterized in that, The thickness of the mica layer is 0.15-0.25 mm; Preferably, the thickness of the first reinforcing layer is 0.02-0.06 mm; Preferably, the thickness of the second reinforcing layer is 0.13-0.25 mm; Preferably, the areal density of the mica layer is 150-200 g / m³. 2 ; Preferably, the areal density of the first reinforcing layer is 10-50 g / m³. 2 ; Preferably, the areal density of the second reinforcing layer is 100-150 g / m³. 2 .

5. A method for preparing a wear-resistant composite mica tape according to any one of claims 1-4, characterized in that, The preparation method includes the following steps: (1) The first reinforcing layer is bonded to the mica layer through the first adhesive layer, and then subjected to the first rolling and first curing processes in sequence to obtain the composite mica tape semi-finished product; (2) The side of the mica layer away from the first adhesive layer is bonded to the second reinforcing layer through the second adhesive layer, and then subjected to the second rolling and second curing treatments in sequence to obtain the wear-resistant composite mica tape.

6. The preparation method according to claim 5, characterized in that, The coating amount of the first adhesive layer is 50-70 g / m 2 ; Preferably, the coating amount of the second adhesive layer is 50-70 g / m². 2 .

7. The preparation method according to claim 5 or 6, characterized in that, The linear pressure of the first roller is 3-10 N / mm; Preferably, the linear pressure of the second roller is 3-10 N / mm.

8. The preparation method according to any one of claims 5-7, characterized in that, The temperature for the first curing treatment is 110-150℃; Preferably, the curing time for the first curing process is 2-5 minutes.

9. The preparation method according to any one of claims 5-8, characterized in that, The temperature for the second curing process is 110-150℃; Preferably, the curing time for the second curing process is 3-8 minutes.

10. The application of a wear-resistant composite mica tape according to any one of claims 1-4 in passive protection against thermal runaway in new energy battery packs.

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