Insulating layer, insulating film, curing and bonding method, battery pack and electric equipment

Abstract

The invention discloses an insulating layer, an insulating film, a curing and bonding method, a battery pack and electric equipment. The insulating layer comprises an insulating base film layer; the curing layer is arranged on at least part of the surface of the insulating base film layer, the curing layer comprises a binding material, and the binding material comprises at least one of a compound shown in a formula I and a compound shown in a formula II; wherein R1 and R2 are respectively a group formed by reacting a curing agent to the compound shown in the formula I, a group formed by reacting a first active monomer to the compound shown in the formula I, a group formed by reacting a second active monomer to the compound shown in the formula II, and a group formed by reacting a third active monomer to the compound shown in the formula II. The insulating layer provided by the invention can provide reliable high-temperature (500 DEG C) insulation protection for metal parts of the battery pack. In addition, the insulating layer provided by the invention has excellent bonding performance on a metal part of the battery pack.

Description

Technical Field

[0001] This application belongs to the field of battery pack technology, specifically relating to an insulating layer, an insulating film, a curing and bonding method, a battery pack, and electrical equipment. Background Technology

[0002] Traditional battery packs typically require PET blue film and polyurethane structural adhesive for insulation between the metal components and the battery cells. However, polyurethane adhesive and PET have poor temperature resistance and will thermally decompose when the battery fails (at a high temperature of 500℃), thus failing to provide effective insulation protection. Therefore, battery packs are at risk of arcing and ignition. Summary of the Invention

[0003] This application aims to at least partially address one of the technical problems in the related art. Therefore, the purpose of this application is to provide an insulating layer, an insulating film, a curing and bonding method, a battery pack, and an electrical device. The insulating layer provided by this application can provide reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. Furthermore, the insulating layer of this application has excellent adhesion properties to the metal components of the battery pack.

[0004] In one aspect of this application, an insulating layer is provided. According to an embodiment of this application, the insulating layer comprises:

[0005] Insulating base film layer;

[0006] A curing layer disposed on at least a portion of the surface of the insulating base film layer, the curing layer comprising an adhesive material, the adhesive material comprising at least one of a compound of Formula I and a compound of Formula II;

[0007]

[0008] Where R1 and R2 are respectively

[0009] M is the group formed by the reaction of the curing agent with the compound shown in Formula I, Q1 is the group formed by the reaction of the first active monomer with the compound shown in Formula I, Q2 is the group formed by the reaction of the second active monomer with the compound shown in Formula II, Q3 is the group formed by the reaction of the third active monomer with the compound shown in Formula II, and n1, n2, n3, n4, n5, and n6 are positive integers in the range of 1 to 2000.

[0010] The insulating layer according to embodiments of this application provides reliable high-temperature (500°C) insulation and corrosion protection for the metal components of the battery pack. Using the insulating layer of this application instead of applying adhesive to insulate the metal components effectively solves the problem that traditional polyurethane adhesives cannot provide effective insulation protection at high temperatures. Furthermore, the insulating layer of this application exhibits excellent adhesion to the metal components of the battery pack.

[0011] In addition, the insulating layer according to the above embodiments of this application may also have the following additional technical features:

[0012] In some embodiments of this application, the mass of the adhesive material accounts for 90% to 98% of the total mass of the cured layer.

[0013] In some embodiments of this application, the cured layer further includes an antioxidant, the antioxidant accounting for 0.5% to 4% of the total mass of the cured layer.

[0014] In some embodiments of this application, the curing agent includes at least one of linear aliphatic polyamines, polyamides, polythiols, acid anhydrides, imidazole compounds, BF3 complexes, and aromatic polyamines.

[0015] In some embodiments of this application, the first active monomer, the second active monomer, and the third active monomer respectively include at least one of diethylene glycol diacrylate, isobornyl methacrylate, glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate, and bisphenol A dimethacrylate.

[0016] In some embodiments of this application, the antioxidant includes at least one of sterically hindered phenolic binary antioxidants, bisphenol-type hindered phenolic antioxidants, polyphenol-type hindered phenolic antioxidants, and monophenol-type hindered phenolic antioxidants.

[0017] In some embodiments of this application, the cured layer further includes an additive, wherein the mass of the additive accounts for 1% to 5% of the total mass of the cured layer.

[0018] In some embodiments of this application, the additives include at least one of leveling agents, plasticizers, defoamers, wetting agents, dispersants, heat stabilizers, light stabilizers, anti-settling agents, ultraviolet absorbers, and anti-skinning agents.

[0019] In some embodiments of this application, the leveling agent accounts for 0.02% to 1% of the total mass of the cured layer; and / or, the defoamer accounts for 0.1% to 1% of the total mass of the cured layer; and / or, the plasticizer accounts for 0.5% to 3% of the total mass of the cured layer.

[0020] In some embodiments of this application, the insulating base film layer includes at least one of a polyimide film layer and a ceramicized modified polyimide film layer; and / or, the thickness of the insulating base film layer is 20 μm to 300 μm.

[0021] In a second aspect, this application provides an insulating film. According to an embodiment of this application, the insulating film comprises:

[0022] Insulating base film layer;

[0023] An adhesive layer is disposed on at least a portion of the surface of the insulating base film layer. The adhesive layer comprises a polyolefin-modified acrylic resin, a photoinitiator, an active monomer, and a curing agent, with the total mass of the adhesive layer being 100%. The content of the polyolefin-modified acrylic resin is 60% to 85%, the content of the photoinitiator is 1% to 5%, the content of the active monomer is 10% to 30%, and the content of the curing agent is 0.5% to 5%.

[0024] According to the embodiments of this application, the insulating film can be applied to the object using only an LED light source device, eliminating the need for a hot-pressing process. This offers advantages such as low equipment cost, low energy consumption, high production efficiency, and ease of use. It also avoids the problem of excessive hot-pressing pressure deforming weaker metal components. Furthermore, after curing, the insulating film is free of defects such as wrinkles, bubbles, scratches, ripples, foreign matter, and damage. Simultaneously, the insulating film of this application provides reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. In addition, the insulating film of this application exhibits excellent adhesion to the metal components of the battery pack.

[0025] In addition, the insulating film according to the above embodiments of this application may also have the following additional technical features:

[0026] In some embodiments of this application, the polyolefin-modified acrylic resin comprises at least one of the compounds shown in Formula III and Formula IV:

[0027]

[0028] Among them, R3 and R4 are respectively

[0029] n4, n5, and n6 are positive integers in the range of 1 to 2000.

[0030] In some embodiments of this application, the photoinitiator comprises at least one selected from 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,1'-diimidazole, 2,5-bis(o-chlorophenyl)-4,4'-dimethylphenyl-1H-imidazolium, 9,10-anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, α-methylbenzoin, and α-phenylbenzoin; and / or, the active monomer comprises diethylene glycol diacrylate, isobornyl methacrylate, etc. The curing agent comprises at least one of the following: glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate, and bisphenol A dimethacrylate; and / or the curing agent comprises at least one of a linear aliphatic polyamine, polyamide, polythiol, acid anhydride, imidazole compound, BF3 complex, and aromatic polyamine; and / or the antioxidant comprises a sterically hindered phenolic binary antioxidant.

[0031] In some embodiments of this application, the adhesive layer further includes an antioxidant, wherein the antioxidant accounts for 1% to 3% of the total mass of the adhesive layer.

[0032] In some embodiments of this application, the adhesive layer further includes an additive, wherein the mass of the additive accounts for 1% to 5% of the total mass of the adhesive layer.

[0033] In some embodiments of this application, the additives include at least one of leveling agents, plasticizers, defoamers, wetting agents, dispersants, heat stabilizers, light stabilizers, anti-settling agents, ultraviolet absorbers, and anti-skinning agents.

[0034] In some embodiments of this application, the insulating base film layer includes at least one of a polyimide film layer and a ceramicized modified polyimide film layer; and / or, the thickness of the insulating base film layer is 20 μm to 300 μm.

[0035] In some embodiments of this application, the insulating film further includes a protective film layer disposed on at least a portion of the surface of the adhesive layer away from the insulating base film layer.

[0036] In some embodiments of this application, the protective film layer includes at least one of PET film layer, PP film layer, PE film layer, polyolefin film layer, polyester PS film layer, PVC film layer, and BOPP film layer; and / or, the thickness of the protective film layer is 10μm to 40μm.

[0037] In a third aspect, this application proposes a method for curing and bonding using the insulating film described in the above embodiments. According to an embodiment of this application, the method includes:

[0038] The adhesive layer of the insulating film is activated using a UV light source;

[0039] The activated insulating film is adhered to the object to be bonded and cured to form an insulating layer.

[0040] According to the method of this application embodiment, only an LED light source device is needed to apply the insulating film to the object, eliminating the need for a hot pressing process. This method offers advantages such as low equipment cost, low energy consumption, and high production efficiency. It also avoids the problem of excessive hot pressing pressure deforming weaker metal parts. Furthermore, after curing, the insulating film is free of defects such as wrinkles, bubbles, scratches, wavy lines, foreign matter, and damage.

[0041] In addition, the method according to the above embodiments of this application may also have the following additional technical features:

[0042] In some embodiments of this application, the energy irradiated onto the adhesive layer is 2000 mJ / cm². 2 ~5000mJ / cm 2 .

[0043] In a fourth aspect, this application proposes a battery pack. According to embodiments of this application, the battery pack has an insulating layer as described above, an insulating layer obtained using the insulating film described above, or an insulating layer obtained by the method described above. This effectively improves the high-temperature resistance and corrosion resistance of the battery pack.

[0044] In some embodiments of this application, the battery pack includes a battery cell and a metal component, the insulating layer is disposed on the metal component, and the insulating layer is disposed between the metal component and the battery cell.

[0045] In a fifth aspect, this application proposes an electrical appliance. According to an embodiment of this application, the electrical appliance has a battery pack as described above. Therefore, the electrical appliance possesses all the advantages of a battery pack, which will not be elaborated further here.

[0046] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0047] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0048] Figure 1This is a schematic diagram of the insulating layer structure according to an embodiment of this application;

[0049] Figure 2 This is a schematic diagram of the structure of the insulating film according to an embodiment of this application;

[0050] Figure 3 The images show the infrared spectra of the unactivated film, partially activated film, and fully activated film of Example 1 of this application.

[0051] Figure label:

[0052] 100 - Insulating base film layer, 200 - Curing layer, 300 - Adhesive layer, 400 - Protective film layer. Detailed Implementation

[0053] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0054] In one aspect of this application, an insulating layer is provided. According to an embodiment of this application, refer to the appendix... Figure 1 The insulating layer includes: an insulating base film layer 100; and a curing layer 200, wherein the curing layer 200 is disposed on at least a portion of the surface of the insulating base film layer 100, and the curing layer 200 includes an adhesive material, wherein the adhesive material includes at least one of the compounds shown in Formula I and Formula II.

[0055]

[0056]

[0057] Where R1 and R2 are respectively M is a group formed by the reaction of a curing agent (e.g., crosslinking) to the compound shown in Formula I; Q1 is a group formed by the reaction of a first active monomer (e.g., grafting) to the compound shown in Formula I; Q2 is a group formed by the reaction of a second active monomer (e.g., grafting) to the compound shown in Formula II; Q3 is a group formed by the reaction of a third active monomer (e.g., grafting) to the compound shown in Formula II; and n1, n2, n3, n4, n5, and n6 are positive integers in the range of 1 to 2000. n1, n2, n3, n4, n5, and n6 all represent the degree of polymerization. Therefore, the insulating layer provided by this application can provide reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. Using the insulating layer of this application to replace the application of adhesive for insulating metal components effectively solves the problem that traditional polyurethane adhesives cannot provide effective insulation protection at high temperatures. Furthermore, the insulating layer of this application has excellent adhesion properties to the metal components of the battery pack.

[0058] It should be noted that the curing agent reacts with the epoxy group in Formula IV to form an M group, and the active monomer reacts with the double bond in Formula IV to form a Q group. The first active monomer, the second active monomer, and the third active monomer may be the same or different.

[0059] The principle by which the insulating layer proposed in this application achieves the above-mentioned beneficial effects will be explained in detail below:

[0060] The insulating layer provided in this application includes an insulating base film layer and a cured layer. The insulating base film layer provides reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. Using this insulating layer instead of applying adhesive to insulate the metal components effectively solves the problem that traditional polyurethane adhesives cannot provide effective insulation protection at high temperatures. Specifically, after baking in a muffle furnace at 500±2°C for 0.5 hours, the insulating layer does not spontaneously combust. After baking in a muffle furnace at 500±2°C for 0.5 hours, the insulating layer is removed, and a voltage of 1000V is applied to both surfaces of the insulating layer for 60 seconds; the insulating layer does not break down.

[0061] The aforementioned cured layer includes at least one of the compounds shown in Formula I and Formula II, which enables the insulating layer of this application to have excellent adhesion to the metal components of the battery pack. Specifically, the tensile shear strength of the aforementioned cured layer to the aluminum plate is greater than 7 MPa, and the pull-out strength of the aforementioned cured layer to the aluminum plate is greater than 7 MPa.

[0062] According to some specific embodiments of this application, the mass of the above-mentioned adhesive material accounts for 90% to 98% of the total mass of the cured layer. Examples include 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, etc., which can further ensure that the insulating layer has excellent adhesion performance to the metal parts of the battery pack.

[0063] The insulating layer in related technologies lacks corrosion resistance, necessitating additional corrosion protection treatment for some metal components in the battery pack. Therefore, the curing layer in this application also includes an antioxidant, which effectively enhances the corrosion resistance of the insulating layer, thereby providing excellent corrosion protection and eliminating the need for additional corrosion protection treatment of the metal components.

[0064] Meanwhile, the antioxidants mentioned above delay or inhibit the oxidation process of the polymer, thereby preventing material aging and extending its service life. Furthermore, by adding antioxidants, the heat resistance and processing stability of the material can be improved. According to some specific embodiments of this application, the antioxidant accounts for 0.5% to 4% of the total mass of the cured layer; examples include 0.5%, 1%, 2%, 3%, and 4%, etc., which further improves the corrosion resistance, aging resistance, and heat resistance of the insulation layer.

[0065] In the embodiments of this application, the specific types of antioxidants are not particularly limited. Those skilled in the art can select them according to actual needs. As some specific embodiments, the antioxidants include at least one of the following: hindered phenolic binary antioxidants, bisphenol-type hindered phenolic antioxidants, polyphenol-type hindered phenolic antioxidants, and monophenol-type hindered phenolic antioxidants, preferably 2,6-di-tert-butyl-4-methylphenol.

[0066] In the embodiments of this application, the curing agent is crosslinked to the compound shown in Formula I via a crosslinking reaction. The specific type of curing agent is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific embodiments, the curing agent includes at least one of linear aliphatic polyamines, polyamides, polythiols, acid anhydrides, imidazole compounds, BF3 complexes, and aromatic polyamines, preferably p-phenylenediamine or m-phenylenediamine.

[0067] In the embodiments of this application, the above-mentioned active monomers are grafted onto the compound shown in Formula I or Formula II via a grafting reaction. The specific types of the above-mentioned active monomers are not particularly limited, and those skilled in the art can select them according to actual needs. As some specific embodiments, the first active monomer, the second active monomer, and the third active monomer respectively include at least one of diethylene glycol diacrylate, isobornyl methacrylate, glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate, and bisphenol A dimethacrylate. Diethylene glycol diacrylate is preferred.

[0068] According to some specific embodiments of this application, the cured layer further includes: additives, including at least one of leveling agents, plasticizers, defoamers, wetting agents, dispersants, heat stabilizers, light stabilizers, anti-settling agents, ultraviolet absorbers, and anti-skinning agents. The leveling agent improves the leveling and uniformity of the cured layer; the plasticizer improves the flexibility and extensibility of the cured layer; the defoamer reduces the generation of bubbles during the preparation of the cured layer, ensuring its uniformity and aesthetics; the wetting agent improves the wetting performance of the cured layer on the substrate, increasing its adhesion; the dispersant helps stabilize pigments and fillers in the cured layer, preventing sedimentation and aggregation, and maintaining the uniformity and stability of the cured layer; the heat stabilizer improves the stability of the cured layer at high temperatures, preventing thermal degradation; and the light stabilizer protects the cured layer from damage by ultraviolet light sources, extending its service life. The anti-settling agent prevents solid particles in the coating from settling during storage, maintaining the uniformity of the cured layer. UV absorbers absorb ultraviolet rays, protecting the cured layer from direct UV damage; they also act as light stabilizers. Anti-skinning agents prevent the formation of a hard skin on the coating surface during storage or drying, maintaining the application properties of the cured layer. These additives, through their unique functions, work together to enhance the performance and application effect of the cured layer.

[0069] According to some specific embodiments of this application, the total mass of the above-mentioned additives accounts for 1% to 5% of the total mass of the cured layer, and examples include 1%, 2%, 3%, 4%, 5%, etc. Specifically, the mass of the leveling agent accounts for 0.02% to 1% of the total mass of the cured layer, and examples include 0.02%, 0.05%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc. The mass of the defoamer accounts for 0.1% to 1% of the total mass of the cured layer, and examples include 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc. The mass of the plasticizer accounts for 0.5% to 3% of the total mass of the cured layer, and examples include 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, etc.

[0070] In the embodiments of this application, the above-mentioned insulating base film layer can provide reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. The specific type is not particularly limited, and those skilled in the art can choose according to actual needs. As some specific embodiments, the insulating base film layer includes at least one of polyimide film layer and ceramic-modified polyimide film layer.

[0071] In some specific embodiments, the thickness of the insulating base film layer is 20μm to 300μm, and examples include 20μm, 50μm, 100μm, 150μm, 200μm, 250μm, and 300μm. This further ensures that the insulating base film layer has reliable high-temperature (500℃) insulation protection performance.

[0072] In a second aspect, this application proposes an insulating film. According to an embodiment of this application, refer to the appendix... Figure 2 The insulating film comprises: an insulating base film layer 100; and an adhesive layer 300 disposed on at least a portion of the surface of the insulating base film layer 100. The adhesive layer 300 comprises polyolefin-modified acrylic resin, a photoinitiator, an active monomer, a curing agent, and an antioxidant. Based on the total mass of the adhesive layer (100%), the content of the polyolefin-modified acrylic resin is 60%–85%, the content of the photoinitiator is 1%–5%, the content of the active monomer is 10%–30%, and the content of the curing agent is 0.5%–5%. Therefore, this application only requires LED light source equipment to apply the insulating film to the object, eliminating the need for a hot-pressing process. This offers advantages such as low equipment cost, low energy consumption, high production efficiency, and ease of use. It also avoids the problem of excessive hot-pressing pressure deforming weaker metal parts. Furthermore, after curing, the surface of the insulating film is free of defects such as wrinkles, bubbles, scratches, ripples, foreign matter, and damage. Meanwhile, the insulating film of this application can provide reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. Furthermore, the insulating film of this application exhibits excellent adhesion to the metal components of the battery pack.

[0073] The principle by which the insulating film proposed in this application achieves the above-mentioned beneficial effects will be explained in detail below:

[0074] The metal components in the battery pack have a large area (more than 2 square meters). The traditional hot-press bonding process (bonding the insulating protective film) has the following drawbacks: the required hot-pressing equipment is expensive, the production efficiency is low, large-area hot-pressing is prone to producing air bubble defects, excessive hot-pressing pressure can deform metal components with low strength, and some metal components need to be treated with anti-corrosion treatment (spraying, electrophoretic anti-corrosion coating), etc.

[0075] In view of this, this application provides a UV-activated high-temperature electrolyte-resistant insulating film. The insulating film includes an insulating base film layer and an adhesive layer. The adhesive layer includes a polyolefin-modified acrylic resin, a photoinitiator, an active monomer, a curing agent, and an antioxidant. Under UV radiation, the photoinitiator absorbs energy to activate the coating, enabling the adhesive layer to undergo a polymerization reaction. The active monomer grafts onto the polyolefin-modified acrylic resin, gradually generating heat, which in turn activates the curing agent, causing the epoxy resin to undergo a ring-opening reaction. This results in the curing agent crosslinking onto the polyolefin-modified acrylic resin, ultimately forming the compound shown in Formula I, thus obtaining the cured layer of the first aspect. After curing, the surface of the insulating film is free of defects such as wrinkles, bubbles, scratches, ripples, foreign matter, and damage. Furthermore, the UV-activated insulating film can be applied to the object using a rubber roller or a manual scraper, eliminating the need for a hot-pressing process compared to existing technologies, making it convenient to use. The existing hot-pressing process requires hot-pressing equipment costing approximately 4 million RMB per unit, while this application only requires LED light source equipment, which costs approximately 20,000 RMB per unit, significantly reducing equipment costs. Existing hot-pressing processes typically require holding at 150°C for 10 minutes; however, the LED light source required for UV activation in this application is a cold light source, resulting in a substantial reduction in production energy consumption. Furthermore, this application can employ a roll-to-roll bonding process to adhere the UV-activated insulating film to the substrate, effectively improving production efficiency and eliminating bubble defects.

[0076] Meanwhile, the cured insulating film provides reliable high-temperature (500℃) insulation protection for the metal components of the battery pack. Using the insulating film of this application instead of applying adhesive to insulate the metal components effectively solves the problem that traditional polyurethane adhesives cannot provide effective insulation protection at high temperatures. Specifically, after baking in a muffle furnace at 500±2℃ for 0.5 hours, the cured insulating film does not spontaneously combust. After baking in a muffle furnace at 500±2℃ for 0.5 hours, the cured insulating film is removed, and a voltage of 1000V is applied to both surfaces of the cured insulating film for 60 seconds; the cured insulating film does not break down. Furthermore, the cured insulating film exhibits excellent adhesion to the metal components of the battery pack. Specifically, the tensile shear strength of the cured insulating film to the aluminum plate is greater than 7MPa, and the pull-out strength of the cured insulating film to the aluminum plate is greater than 7MPa.

[0077] In the embodiments of this application, the adhesive layer comprises polyolefin-modified acrylic resin, photoinitiator, active monomer, curing agent, and antioxidant. With the total mass of the adhesive layer as 100%, the content of the polyolefin-modified acrylic resin is 60%–85% (examples include 60%, 65%, 70%, 75%, 80%, 85%, etc.), and the content of the photoinitiator is 1%–5% (examples include 1%, 2%, 3%, 4%, 5%, etc., preferably 2%). The adhesive layer contains 5% to 4% active monomers, 10% to 30% (examples include 10%, 15%, 20%, 25%, 30%, etc., preferably 15% to 25%), 0.5% to 5% curing agent (examples include 0.5%, 1%, 2%, 3%, 4%, 5%, etc., preferably 2% to 4%), and 1% to 3% antioxidant (examples include 1%, 1.5%, 2%, 2.5%, 3%). By limiting the content of each component in the adhesive layer to the above ranges, it is possible to effectively ensure that the insulating film of this application can provide reliable high-temperature (500°C) insulation and corrosion protection for the metal components of the battery pack, while ensuring that the insulating film of this application has excellent adhesion to the metal components of the battery pack.

[0078] According to some specific embodiments of this application, the above-mentioned polyolefin modified acrylic resin includes at least one of the compounds shown in Formula III and Formula IV:

[0079]

[0080] Among them, R3 and R4 are respectively

[0081] n4, n5, and n6 are positive integers in the range of 1 to 2000, and n4, n5, and n6 all represent the degree of aggregation.

[0082] The formation process of the above-mentioned polyolefin-modified acrylic resin is as follows:

[0083]

[0084] In the embodiments of this application, the specific type of photoinitiator is not particularly limited, and those skilled in the art can select one according to actual needs. As some specific embodiments, the photoinitiator includes at least one selected from 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,1'-diimidazole, 2,5-bis(o-chlorophenyl)-4,4'-dimethylphenyl-1H-imidazole, 9,10-anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, α-methylbenzoin, and α-phenylbenzoin. Preferably, 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole is used.

[0085] In the embodiments of this application, the specific types of the active monomers are not particularly limited, and those skilled in the art can select them according to actual needs. As some specific embodiments, the active monomers include at least one selected from diethylene glycol diacrylate, isobornyl methacrylate, glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate, and bisphenol A dimethacrylate. Diethylene glycol diacrylate is preferred.

[0086] In the embodiments of this application, the specific type of curing agent is not particularly limited. Those skilled in the art can select according to actual needs. As some specific embodiments, the curing agent includes at least one of linear aliphatic polyamines, polyamides, polythiols, acid anhydrides, imidazole compounds, BF3 complexes, and aromatic polyamines, preferably p-phenylenediamine and m-phenylenediamine.

[0087] The insulating layer in related technologies lacks corrosion resistance, necessitating additional corrosion protection treatment for some metal components in the battery pack. Therefore, the adhesive layer in this application also includes an antioxidant, which effectively enhances the corrosion resistance of the cured insulating film. This results in the cured insulating film possessing excellent corrosion resistance, eliminating the need for additional corrosion protection treatment for the metal components.

[0088] In the embodiments of this application, the specific types of antioxidants are not particularly limited, and those skilled in the art can select them according to actual needs. As some specific embodiments, antioxidants include sterically hindered phenolic binary antioxidants, preferably 2,6-di-tert-butyl-4-methylphenol.

[0089] According to some specific embodiments of this application, the adhesive layer further includes: additives, including at least one of leveling agents, plasticizers, defoamers, wetting agents, dispersants, heat stabilizers, light stabilizers, anti-settling agents, UV absorbers, and anti-skinning agents. The leveling agent helps the coating form a smooth, uniform film during the drying process by reducing the surface tension of the film, thereby improving its leveling and uniformity. The plasticizer increases the flexibility and extensibility of the coating, making it easier to apply and reducing brittleness. The defoamer reduces air bubbles generated during the manufacturing and application process, ensuring the uniformity and aesthetics of the coating. The wetting agent improves the wetting properties of the coating on the substrate, enhancing its adhesion, particularly for improving the adhesion of primers to substrates. The dispersant helps stabilize pigments and fillers in the coating, preventing sedimentation and aggregation, and maintaining the uniformity and stability of the coating. The heat stabilizer improves the stability of the coating during high-temperature processing and prevents thermal degradation. Light stabilizers protect coatings from damage caused by ultraviolet (UV) light sources, extending their lifespan. Anti-settling agents prevent solid particles in the coating from settling during storage, maintaining the coating's uniformity. UV absorbers absorb UV rays, protecting the coating from direct UV damage and also function as light stabilizers. Anti-skinning agents prevent the formation of a hard skin on the coating surface during storage or drying, maintaining the coating's workability. These additives, through their unique functions, work together to enhance the coating system, improving its performance and application results.

[0090] According to further specific embodiments of this application, the total mass of the above-mentioned additives accounts for 1% to 5% of the total mass of the adhesive layer, and examples include 1%, 2%, 3%, 4%, 5%, etc. Specifically, the mass of the leveling agent accounts for 0.02% to 1% of the total mass of the adhesive layer, and examples include 0.02%, 0.05%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc., preferably 0.05% to 0.5%. The mass of the defoamer accounts for 0.1% to 1% of the total mass of the adhesive layer, and examples include 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc., preferably 0.3% to 0.5%. The mass of the plasticizer accounts for 0.5% to 3% of the total mass of the adhesive layer, and examples include 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, etc., preferably 0.8% to 2%.

[0091] As some specific embodiments, the leveling agent mentioned above includes at least one of silicone, polyacrylate, and nitrocellulose, preferably nitrocellulose.

[0092] As some specific embodiments, the above-mentioned defoamer can be a polyether-based defoamer.

[0093] As some specific embodiments, the plasticizers mentioned above can be aliphatic diester plasticizers, polyester plasticizers, fatty acid ester plasticizers, epoxy plasticizers, etc., with isooctyl palmitate being preferred.

[0094] In the embodiments of this application, the above-mentioned insulating base film layer can provide reliable high-temperature (500°C) insulation protection for the metal components of the battery pack. The specific type is not particularly limited, and those skilled in the art can choose according to actual needs. As some specific embodiments, the insulating base film layer includes at least one of polyimide film layer and ceramic-modified polyimide film layer.

[0095] In some specific embodiments, the thickness of the insulating base film layer is 20μm to 300μm, and examples include 20μm, 50μm, 100μm, 150μm, 200μm, 250μm, and 300μm. This further ensures that the insulating base film layer has reliable high-temperature (500℃) insulation protection performance.

[0096] According to some further specific embodiments of this application, refer to the appendix. Figure 2 The insulating film further includes a protective film layer 400, which is disposed on at least a portion of the surface of the adhesive layer 300 away from the insulating base film layer 100, for protecting the adhesive layer 300 and preventing the adhesive layer 300 from being activated when not in use.

[0097] In the embodiments of this application, the specific type of the protective film layer is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific embodiments, the protective film layer includes at least one of black PET film, PP film, PE film, polyolefin film, polyester PS film, PVC film, and BOPP film. PET film is preferred.

[0098] As some specific embodiments, the thickness of the above-mentioned protective film layer can be 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, etc. Preferably, it is 15μm to 35μm.

[0099] In the embodiments of this application, the method for preparing the above-mentioned insulating film is as follows:

[0100] Polyolefin-modified acrylic resin, photoinitiator, active monomer, curing agent, additives, and antioxidant are mixed to prepare polyolefin-modified acrylic resin adhesive coating.

[0101] The above-mentioned polyolefin-modified acrylic resin adhesive coating is applied to the insulating film base film and dried to form an adhesive layer;

[0102] A protective film layer is rolled onto the surface of the adhesive layer to obtain an insulating film.

[0103] In a third aspect, this application proposes a method for curing and bonding using the insulating film described in the above embodiments. According to an embodiment of this application, the method includes:

[0104] S100: The adhesive layer of the insulating film is activated using a UV light source.

[0105] In this step, a UV light source is used to activate the adhesive layer of the insulating film. Under UV radiation, the photoinitiator absorbs energy, activating the coating and enabling the adhesive layer to undergo a polymerization reaction. Active monomers are grafted onto the polyolefin-modified acrylic resin (compounds shown in Formula III and / or Formula IV), gradually generating heat to activate the curing agent. This causes the epoxy resin (compound shown in Formula IV) to undergo a ring-opening reaction, resulting in the curing agent crosslinking onto the polyolefin-modified acrylic resin, ultimately forming compounds shown in Formula I and / or Formula II. It should be noted that only the compound shown in Formula IV undergoes a ring-opening reaction, resulting in the curing agent crosslinking onto the compound shown in Formula IV to obtain the compound shown in Formula I; the compound shown in Formula III only undergoes an active monomer grafting reaction, resulting in the compound shown in Formula II.

[0106] Taking diethylene glycol diacrylate as an example of the reactive monomer and p-phenylenediamine as an example of the curing agent, the above reaction process is as follows:

[0107]

[0108] Among them, R4 is n4, n5, and n6 are positive integers in the range of 1 to 2000, and each represents the degree of polymerization. R5 is R5=CH2CH2O.

[0109] As some specific embodiments, a 365nm LED light source can be used to activate the adhesive layer of the insulating film.

[0110] According to some specific embodiments of this application, the energy irradiated onto the adhesive layer is 2000 mJ / cm². 2 ~5000mJ / cm 2 .

[0111] According to some specific embodiments of this application, when the insulating film also includes a protective film layer, the protective film layer can be peeled off first, and then the adhesive layer can be activated.

[0112] S200: Apply the activated insulating film to the object to be bonded and allow it to cure.

[0113] In this step, the activated insulating film is adhered to the object to be bonded within 30 minutes of light exposure, and then cured to form an insulating layer.

[0114] In the embodiments of this application, the UV-activated insulating film can be applied to the object using rubber roller pressing or manual scraping, eliminating the need for a hot-pressing process compared to existing technologies. The hot-pressing equipment required by existing technologies costs approximately 4 million RMB per unit, while this application only requires LED light source equipment, which costs approximately 20,000 RMB per unit, significantly reducing equipment costs. Existing hot-pressing processes typically require holding at 150°C for 10 minutes; however, the LED light source required for UV activation in this application is a cold light source, resulting in a substantial reduction in production energy consumption. Furthermore, this application can also employ a roll-to-plate bonding process to apply the UV-activated insulating film to the object, effectively improving production efficiency and eliminating bubble defects.

[0115] According to the method of this application embodiment, only an LED light source device is needed to apply the insulating film to the object, eliminating the need for a hot pressing process. This method offers advantages such as low equipment cost, low energy consumption, and high production efficiency. It also avoids the problem of excessive hot pressing pressure deforming weaker metal parts. Furthermore, after curing, the insulating film is free of defects such as wrinkles, bubbles, scratches, wavy lines, foreign matter, and damage.

[0116] In a fourth aspect, this application proposes a battery pack. According to embodiments of this application, the battery pack has an insulating layer as described in the above embodiments, an insulating layer obtained using the insulating film of the above embodiments, or an insulating layer obtained by the method of the above embodiments. The insulating layer is disposed on the metal components of the battery pack and located between the metal components and the battery cells, serving as insulation protection. This effectively improves the high-temperature resistance and corrosion resistance of the battery pack.

[0117] In a fifth aspect, this application proposes an electrical appliance. According to an embodiment of this application, the electrical appliance has a battery pack as described above. Therefore, the electrical appliance possesses all the advantages of a battery pack, which will not be elaborated further here.

[0118] Specifically, the aforementioned electrical equipment can include, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0119] It should be noted that the features and advantages described above for the battery pack also apply to this electrical device, and will not be repeated here.

[0120] The embodiments of this application are described in detail below. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. In addition, unless otherwise specified, all reagents used in the following embodiments are commercially available or can be synthesized according to the methods described herein or known methods. For reaction conditions not listed, they are also readily available to those skilled in the art.

[0121] Example 1

[0122] This embodiment provides an insulating layer, the preparation method of which includes:

[0123] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 72 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of reactive monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol. The polyolefin-modified acrylic resin was purchased from Foshan Huifengsheng Trading Co., Ltd. The additives included 0.3 wt% of leveling agent nitrocellulose, 0.4 wt% of polyether defoamer, and 1.3 wt% of plasticizer isooctyl palmitate.

[0124] 2) The above-mentioned polyolefin modified acrylic resin adhesive coating is applied to an insulating film base film (commercially available biaxially oriented polyimide film) with a thickness of 100μm, and after drying, an adhesive layer is formed.

[0125] 3) Roll-press a 25μm thick black PET film onto the surface of the adhesive layer to obtain an insulating film.

[0126] 4) Peel off the black PET film and activate the adhesive layer using a 365nm LED light source with an energy of 3000mJ / cm². 2 After exposure to light, within 30 minutes, the UV-activated adhesive layer is applied to the aluminum plate using a roller press. After curing, an insulating layer is formed.

[0127] Example 2

[0128] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0129] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 65 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 27 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0130] Example 3

[0131] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0132] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 80 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 12 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0133] Example 4

[0134] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0135] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 73 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 1 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0136] Example 5

[0137] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0138] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 69 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 5 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0139] Example 6

[0140] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0141] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 73 wt% of polyolefin-modified acrylic resin, 1 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0142] Example 7

[0143] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0144] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 70 wt% of polyolefin-modified acrylic resin, 4 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 2 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0145] Example 8

[0146] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0147] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 73 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 1 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0148] Example 9

[0149] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0150] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 71 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 20 wt% of active monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, 2 wt% of additives, and 3 wt% of antioxidant 2,6-di-tert-butyl-4-methylphenol.

[0151] Example 10

[0152] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0153] 1) Replace the active monomer diethylene glycol diacrylate with isobornyl methacrylate.

[0154] Example 11

[0155] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0156] 1) Replace the active monomer diethylene glycol diacrylate with 2-phenoxyethyl methacrylate.

[0157] Example 12

[0158] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0159] 1) Replace the active monomer diethylene glycol diacrylate with 2-phenoxyethyl acrylate.

[0160] Example 13

[0161] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0162] 1) Replace the curing agent m-phenylenediamine with polyamide.

[0163] Example 14

[0164] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0165] 1) Replace the curing agent m-phenylenediamine with polythiol.

[0166] Example 15

[0167] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0168] 1) Replace the curing agent m-phenylenediamine with acid anhydride.

[0169] Example 16

[0170] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0171] 1) Replace the photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole with 9,10-anthraquinone.

[0172] Example 17

[0173] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0174] 1) Replace the photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole with α-methylbenzoin.

[0175] Example 18

[0176] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0177] 1) Replace the photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole with α-methylbenzoin.

[0178] Example 19

[0179] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0180] 4) Peel off the black PET film and activate the adhesive layer using a 365nm LED light source with an energy of 2000mJ / cm². 2 .

[0181] Example 20

[0182] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0183] 4) Peel off the black PET film and activate the adhesive layer using a 365nm LED light source with an energy of 4000mJ / cm². 2 .

[0184] Example 21

[0185] This embodiment provides an insulating layer. The preparation method of this embodiment is basically the same as that of Embodiment 1, except that:

[0186] 1) A polyolefin-modified acrylic resin adhesive coating was prepared by mixing 73 wt% of polyolefin-modified acrylic resin, 2 wt% of photoinitiator 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazolium, 21 wt% of reactive monomer diethylene glycol diacrylate, 2 wt% of curing agent m-phenylenediamine, and 2 wt% of additives. That is, Example 21 does not contain antioxidants.

[0187] Comparative Example 1

[0188] This comparative example provides a PET blue film, which is applied to an aluminum plate manually or using a laminating device (room temperature laminating device).

[0189] Comparative Example 2

[0190] This comparative example provides a polyurethane adhesive, which is applied to an aluminum plate using an adhesive applicator.

[0191] The contents of adhesive material, antioxidant and additives in the adhesive layers formed in Examples 1 to 9 were tested respectively, and the results are shown in Table 1.

[0192] Table 1

[0193]

[0194]

[0195] Figure 3 These are infrared spectrum curves of the unactivated film, partially activated film (when irradiation energy is insufficient), and fully activated film of Example 1, wherein the unactivated film has an infrared spectrum at 915 cm⁻¹. -1 There is a distinct infrared absorption peak at the C=C bond of the terminal acrylic acid, and the partially activated film shows an infrared absorption peak at 915 cm⁻¹. -1 There is a slight infrared absorption peak at the C=C bond of the terminal acrylic acid, and the fully activated film shows an infrared absorption peak at 915 cm⁻¹. -1 The absence of a peak at this location indicates that the C=C terminal of the acrylic acid in the material has fully participated in the reaction. Furthermore, in both partially and fully activated films, the peak at 1509 cm⁻¹... -1 1607cm -1 The two peaks were significantly weaker than those of the unactivated film, indicating that the overall content of C=C bonds in the activated film was reduced.

[0196] The tensile shear strength and pull-out strength of the insulating layers in Examples 1-21 and Comparative Examples 1-2 to the aluminum plates were tested, and the results are shown in Table 2. The insulating layers of Examples 1-21 and Comparative Examples 1-2, applied to the aluminum plates, were baked in a muffle furnace at 500±2℃ for 0.5 hours. After baking, the adhesive film was removed, and a voltage of 1000V was applied to both surfaces of the film for 60 seconds. The film was then observed to see if it was broken down, and the results are shown in Table 2. After 1344 hours of salt spray treatment, the tensile shear strength and pull-out strength of the insulating layers of Examples 1-21 and Comparative Examples 1-2 to the aluminum plates were tested, and the results are shown in Table 2. The presence of rust on the aluminum plates of the metal parts in Examples 1-21 and Comparative Examples 1-2 was observed, and the results are shown in Table 2.

[0197] The tensile shear strength was tested according to GB / T 7124—2008, and the pull-out strength was tested according to GB / T 6329.

[0198] Table 2

[0199]

[0200]

[0201] As can be seen from Table 2, compared with Comparative Examples 1 and 2, the insulating layer of Examples 1 to 21 was not broken down after being baked at high temperature. This shows that the insulating layer of Examples 1 to 21 can provide reliable high-temperature (500°C) insulation protection for the metal parts of the battery pack.

[0202] As can be seen from Table 2, compared with Comparative Examples 1 and 2, the tensile shear strength and pull-out strength of the insulating layer of Examples 1 to 21 on the aluminum plate are significantly improved. Furthermore, after 1344 hours of salt spray treatment, the tensile shear strength and pull-out strength of the insulating layer of Examples 1 to 21 on the aluminum plate are also significantly higher than those of Comparative Examples 1 and 2 after salt spray treatment, demonstrating that the insulating layer of this application has excellent adhesion properties to the metal components of the battery pack.

[0203] As can be seen from Table 2, Examples 1-20 exhibit superior corrosion resistance compared to Comparative Examples 1 and 2. Compared to Example 21, Examples 1-20 also demonstrate superior corrosion resistance. This indicates that adding an antioxidant to the adhesive layer effectively improves the corrosion resistance of the cured insulating film, thereby enabling the cured insulating film of this application to possess excellent corrosion resistance, eliminating the need for additional corrosion protection treatment of metal components.

[0204] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0205] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An insulating layer, characterized by, The application relates to an insulating base film layer and a curing layer. The curing layer is arranged on at least part of the surface of the insulating base film layer, and the curing layer comprises a bonding material, wherein the bonding material comprises at least one of a compound shown in formula I and a compound shown in formula II. M is a group formed by a curing agent reacting with the compound shown in formula I, Q1 is a group formed by a first active monomer reacting with the compound shown in formula I, Q2 is a group formed by a second active monomer reacting with the compound shown in formula II, Q3 is a group formed by a third active monomer reacting with the compound shown in formula II, and n1, n2, n3, n4, n5 and n6 are positive integers in the range of 1-2000. wherein R1and R2are each The mass of the bonding material accounts for 90-98% of the total mass of the curing layer.

2. The insulating layer of claim 1, wherein The curing layer further comprises an antioxidant, and the mass of the antioxidant accounts for 0.5-4% of the total mass of the curing layer.

3. The insulating layer of claim 1, wherein The curing agent comprises at least one of a linear aliphatic polyamine, a polyamide, a polythiol, an acid anhydride, an imidazole compound, a BF3 complex and an aromatic polyamine.

4. The insulation layer of claim 1, wherein The first active monomer, the second active monomer and the third active monomer each comprise at least one of diethylene glycol diacrylate, isobornyl methacrylate, glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate and ethoxylated bisphenol A dimethacrylate.

5. The insulation layer of claim 1, wherein The antioxidant comprises at least one of a steric hindering phenolic binary antioxidant, a bisphenol type hindered phenolic antioxidant, a polyphenol type hindered phenolic antioxidant and a monophenol type hindered phenolic antioxidant.

6. The insulation layer of claim 3, wherein The curing layer further comprises an auxiliary agent, and the mass of the auxiliary agent accounts for 1-5% of the total mass of the curing layer.

7. The insulation layer of claim 1, wherein The auxiliary agent comprises at least one of a leveling agent, a plasticizer, a defoaming agent, a wetting agent, a dispersing agent, a heat stabilizer, a light stabilizer, an anti-settling agent, an ultraviolet absorber and an anti-skinning agent.

8. The insulation layer of claim 7, wherein, The mass of the leveling agent accounts for 0.02-1% of the total mass of the curing layer.

9. The insulation layer of claim 8, wherein, The mass of the defoaming agent accounts for 0.1-1% of the total mass of the curing layer. The mass of the plasticizer accounts for 0.5-3% of the total mass of the curing layer. The insulating base film layer comprises at least one of a polyimide film layer and a ceramic modified polyimide film layer.

10. The insulating layer according to any one of claims 1 to 9, characterized in that, The thickness of the insulating base film layer is 20-300 microns. The application relates to an insulating base film layer and a curing layer.

11. An insulating film, characterized by The bonding layer is arranged on at least part of the surface of the insulating base film layer, and the bonding layer comprises a polyolefin modified acrylic resin, a photoinitiator, an active monomer and a curing agent. The polyolefin modified acrylic resin comprises at least one of a compound shown in formula III and a compound shown in formula IV. n4, n5 and n6 are positive integers in the range of 1-2000.

12. The insulating film according to claim 11, characterized by ​ wherein R3and R4are each independently ​ 13. The insulating film according to claim 11, characterized by The photo initiator includes at least one of 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl 1,1'-biimidazole, 2,5-bis(o-chlorophenyl)-4,4'-dimethylphenyl-1H-imidazole, 9,10-anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, α-methylbenzoin, and α-phenylbenzoin; And / or, the active monomer includes at least one of diethylene glycol diacrylate, isobornyl methacrylate, glycerol triacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 2-phenoxyethyl acrylate, 2-(p-chlorophenoxyethyl methacrylate), 2-phenoxyethyl methacrylate, tetraethylene glycol dimethacrylate, and ethoxylated bisphenol A dimethacrylate; And / or, the curing agent includes at least one of a linear aliphatic polyamine, a polyamide, a polythiol, an acid anhydride, an imidazole compound, a BF3 complex, and an aromatic polyamine.

14. The insulating film according to claim 11, characterized by The adhesive layer further includes an antioxidant, and a mass of the antioxidant accounts for 1% to 3% of a total mass of the adhesive layer.

15. The insulating film according to claim 14, characterized in that, The adhesive layer further includes an auxiliary agent, and a mass of the auxiliary agent accounts for 1% to 5% of the total mass of the adhesive layer.

16. The insulating film according to claim 15, characterized by The auxiliary agent includes at least one of a leveling agent, a plasticizer, a defoaming agent, a wetting agent, a dispersant, a heat stabilizer, a light stabilizer, an anti-settling agent, an ultraviolet absorber, and a skinning prevention agent. And / or, the antioxidant includes at least one of a steric hindering phenolic binary antioxidant, a bisphenol type hindered phenolic antioxidant, a polyphenol type hindered phenolic antioxidant, and a monophenol type hindered phenolic antioxidant.

17. The insulating film according to any one of claims 11 to 16, characterized by The insulating base film layer includes at least one of a polyimide film layer and a ceramic modified polyimide film layer. And / or, a thickness of the insulating base film layer is 20 μm to 300 μm.

18. The insulating film according to any one of claims 11 to 16, characterized by Further including: A protective film layer disposed on at least a portion of a surface of the adhesive layer away from the insulating base film layer.

19. The insulating film according to claim 18, wherein The protective film layer includes at least one of a PET film layer, a PP film layer, a PE film layer, a polyolefin film layer, a polyester PS film layer, a PVC film layer, and a BOPP film layer. And / or, a thickness of the protective film layer is 10 μm to 40 μm.

20. A method for curing adhesion using the insulating film according to any one of claims 11 to 19, characterized by, Including: Activating an adhesive layer of an insulating film by using a UV light source; Pasting the activated insulating film on a pasting object, curing, and forming an insulating layer.

21. The method of claim 20, wherein, The energy irradiated onto the adhesive layer is 2000 mJ / cm 2 ~ 5000 mJ / cm 2 .

22. A battery pack, characterized by The insulating layer of any one of claims 1 to 10, the insulating layer obtained by using the insulating film of any one of claims 11 to 19, or the insulating layer obtained by the method of claim 20 or 21.

23. The battery pack of claim 22, wherein, The battery pack includes a cell and a metal component, and the insulating layer is disposed on the metal component and between the metal component and the cell.

24. An electrical device, comprising: The battery pack of claim 23.

Images