An acrylate UV pressure-sensitive adhesive for battery cell film and a preparation method thereof

Abstract

This invention belongs to the field of adhesive technology, specifically an acrylic UV pressure-sensitive adhesive for battery cell bonding films and its preparation method. The pressure-sensitive adhesive, by weight, comprises: 10-30 parts of polyurethane acrylate prepolymer, 60-140 parts of acrylate diluent monomer, 1-5 parts of photoinitiator, 0.5-3 parts of adhesion promoter, 0.05-0.5 parts of chain transfer agent, and 2-10 parts of tackifying resin; wherein the diluent monomer contains specific proportions of monofunctional, bifunctional, and phosphorus / carboxyl functional monomers. The preparation method involves mixing the components uniformly in a specific order. Through the synergistic effect of the above components, this invention achieves solvent-free UV rapid curing. The resulting adhesive layer possesses excellent initial tack, high peel strength, and significantly improved high-temperature shear strength and environmental aging resistance, making it perfectly suitable for insulating films for power battery cells with extremely high reliability requirements. It effectively replaces traditional, environmentally unfriendly, and high-temperature-prone solvent-based pressure-sensitive adhesives.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, and more particularly to an acrylic UV pressure-sensitive adhesive for battery cell bonding and its preparation method. Background Technology

[0002] In the fields of new energy vehicles and energy storage, the outer surface of square lithium-ion battery cells typically needs to be covered with an insulating film (such as blue PET film) to provide insulation protection, prevent short circuits, and serve as an identification feature. Currently, this insulating film is mostly applied using solvent-based acrylic pressure-sensitive adhesive. However, this technical approach has significant drawbacks: First, the production process requires a large amount of organic solvents (such as ethyl acetate), and the solvents need to be removed through a high-temperature drying tunnel after coating, resulting in high emissions of volatile organic compounds and high energy consumption, which is inconsistent with the trend of green manufacturing. Second, solvent-based adhesives usually have low molecular weight and limited cross-linking density. Under the high-temperature environment (such as above 60°C) that the battery cell may experience during operation or storage, its shear strength decreases significantly, posing a risk of adhesive layer creep, insulating film lifting, or even detachment, seriously affecting the long-term safety and reliability of the battery.

[0003] Ultraviolet (UV) curing technology is widely used in the adhesive field due to its advantages of high efficiency, environmental friendliness, and energy saving. Several UV-curable adhesives for battery applications already exist in the prior art. For example, Chinese patent application CN120209632A discloses a UV inkjet adhesive containing specific proportions of acrylate monomers, hydrogenated polybutadiene-modified acrylate oligomers, and anhydride-modified acrylate oligomers, designed to provide excellent resistance to environmental aging for insulation protection of battery cell casings. This technology focuses on forming a hard, dense "structural adhesive" or "protective coating," which has a high modulus after curing but lacks the room-temperature tack and reusable properties required by pressure-sensitive adhesives.

[0004] For example, Chinese patent application CN117229744A discloses a fast-curing UV adhesive for the outer layer protection of power batteries. It employs a composite oligomer system of bisphenol A epoxy acrylate modified with a dibasic acid, tetrafunctional branched polyester acrylate, and polyurethane acrylate, aiming for high insulation, salt spray resistance, and rapid curing. The cured product of this solution also exhibits high crosslinking density and high hardness. Its technical objective is to replace PET blue film as a directly coated insulating "coating," rather than a "pressure-sensitive adhesive" used for bonding insulating films.

[0005] Therefore, applying UV curing technology to the field of battery cell film bonding is not a simple replacement. The core challenge lies in designing a UV curing system that, after curing, exhibits the high initial tack, suitable peel strength, and holding power required of pressure-sensitive adhesives, while also meeting the specific requirements of battery cell applications for high temperature resistance and aging resistance. Existing UV adhesive formulations, which focus on insulation protection, cannot simultaneously meet these conflicting performance requirements due to their pursuit of high hardness and high crosslinking density. Summary of the Invention

[0006] This invention proposes an acrylic UV pressure-sensitive adhesive for battery cell bonding and its preparation method, aiming to solve the technical problems of solvent-based adhesives for battery cell bonding being environmentally unfriendly and prone to failure at high temperatures, as well as the technical problems of existing UV adhesives being unable to have excellent pressure-sensitive bonding performance due to the pursuit of high hardness.

[0007] In a first aspect, the present invention provides an acrylic UV pressure-sensitive adhesive for battery cell bonding films, which, by weight, comprises the following components: 10 to 30 parts of polyurethane acrylate prepolymer, 60 to 140 parts of acrylate diluent monomer, 1 to 5 parts of photoinitiator, 0.5 to 3 parts of adhesion promoter, 0.05 to 0.5 parts of chain transfer agent, 2 to 10 parts of tackifying resin, and 0 to 5 parts of additives. The acrylate diluent monomers include monofunctional acrylate monomers, difunctional acrylate monomers, and phosphorus- or carboxyl-containing acrylate functional monomers; based on the total mass of the acrylate diluent monomers as 100%, the content of the monofunctional acrylate monomers is 70% to 95%, the content of the difunctional acrylate monomers is 5% to 25%, and the content of the phosphorus- or carboxyl-containing acrylate functional monomers is 0.5% to 5%.

[0008] The technical advantages of the acrylic UV pressure-sensitive adhesive for battery cell bonding disclosed in this invention are: it provides a solvent-free UV pressure-sensitive adhesive that has both high peel strength and high heat shear strength after curing, achieving a balance between environmental friendliness, adhesion and high-temperature reliability in its formulation.

[0009] Further, the polyurethane acrylate prepolymer is prepared by a method comprising the following steps: reacting a polyether diol or polyester diol with a number-average molecular weight of 400 to 2000 with a diisocyanate under the action of a catalyst to obtain an isocyanate-terminated prepolymer, which is then reacted with a hydroxy acrylate monomer to end-cap the prepolymer; the number-average molecular weight of the polyurethane acrylate prepolymer is 5000 to 20000.

[0010] Further, the monofunctional acrylate monomer is selected from at least one of isooctyl acrylate, isobornyl acrylate, lauryl acrylate, and benzyl acrylate; the difunctional acrylate monomer is selected from at least one of 1,6-hexanediol diacrylate, dipropylene glycol diacrylate, and tricyclodecanediethanol diacrylate; the phosphorus-containing or carboxyl-containing acrylate functional monomer is selected from at least one of hydroxyethyl acrylate phosphate, hydroxyethyl methacrylate phosphate, and acrylic acid.

[0011] Furthermore, the photoinitiator is a mixture of 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-isopropylthioxanthone, and 1-hydroxycyclohexylphenyl ketone, and the mass ratio of the three is 1:1:1, 2:1:1, 3:1:1, 1.5:1:1, or 2:1:1.5.

[0012] Further, the chain transfer agent is at least one of isooctyl mercaptoacetate, dodecyl mercaptoethanol, or isooctyl 3-mercaptopropionate.

[0013] Secondly, the present invention provides a method for preparing an acrylic UV pressure-sensitive adhesive for battery cell bonding films, the method comprising the following steps: S1, mix the acrylate diluent monomer, adhesion promoter, chain transfer agent, tackifying resin and optional additives according to the formula, stir and disperse evenly to obtain the first mixture; S2, add photoinitiator to the first mixture and stir until completely dissolved to obtain the second mixture; S3, add polyurethane acrylate prepolymer to the second mixture, stir and mix evenly, filter, and the acrylate UV pressure-sensitive adhesive is obtained.

[0014] The technical advantage of the method for preparing acrylate UV pressure-sensitive adhesive for battery cell bonding disclosed in this invention is that it provides a simple process suitable for large-scale continuous production of solvent-free UV pressure-sensitive adhesive, and ensures the uniformity and stability of the adhesive solution through a specific feeding and mixing sequence.

[0015] Furthermore, the polyurethane acrylate prepolymer is prepared by the following steps: S31, dehydrate polyether diol or polyester diol at 110°C to 130°C under vacuum for 1 to 3 hours; S32, the dehydrated diol is cooled to 60 to 70 degrees Celsius, diisocyanate and catalyst are added, and the reaction is carried out at 70 to 80 degrees Celsius until the NCO content of the system reaches the theoretical value, to obtain the terminal isocyanate group prepolymer; S33, add hydroxy acrylate monomer and polymerization inhibitor to the terminal isocyanate prepolymer, and react at 75°C to 85°C until the NCO characteristic peak disappears to obtain the polyurethane acrylate prepolymer.

[0016] Furthermore, in step S3, the stirring and mixing are carried out under light-protected conditions, the mixing temperature is 25 degrees Celsius to 40 degrees Celsius, and the mixing time is 1 hour to 3 hours.

[0017] Thirdly, the present invention provides a battery cell adhesive tape, comprising a substrate layer and the pressure-sensitive adhesive coated on at least one side of the substrate layer.

[0018] The technical effect of the battery cell bonding tape disclosed in this invention is that it provides a battery cell bonding tape using the above-mentioned UV pressure-sensitive adhesive, which has a firm bonding of the insulating film, and its reliability is significantly improved, especially in high-temperature environments, thus ensuring battery safety.

[0019] Furthermore, the substrate layer is a polyethylene terephthalate film, a polyimide film, or a polyolefin film, with a thickness of 10 micrometers to 50 micrometers; the thickness of the pressure-sensitive adhesive layer is 10 micrometers to 30 micrometers. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart illustrating a method for preparing an acrylic UV pressure-sensitive adhesive for battery cell bonding, as proposed in an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used, unless otherwise specified, are all conventional products that can be purchased through legitimate channels.

[0023] like Figure 1 As shown, the preparation process of the pressure-sensitive adhesive of this invention mainly includes: synthesis of polyurethane acrylate prepolymer → metering and mixing of each component of the pressure-sensitive adhesive → filtration of adhesive solution → coating onto substrate → UV curing → winding / slitting. This process is efficient, continuous, and solvent-free.

[0024] (1) Preparation of polyurethane acrylate prepolymer: By controlling the types, proportions and process parameters of raw materials, a prepolymer with a number average molecular weight (Mn) between 5000 and 20000 and suitable performance is obtained.

[0025] Preparation Example 1 (corresponding to PUA-1): In a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen inlet, 200.0 g (0.20 mol) of polypropylene glycol (PPG, Mn=1000, water content <200 ppm) that had been dehydrated under vacuum at 120 °C and -0.095 MPa for 2 hours was added. The temperature was lowered to 65 °C, and 49.2 g of 0.22 mol of isophorone diisocyanate (IPDI) and 0.05 g of dibutyltin dilaurate (DBTDL) were added. The temperature was slowly raised to 75 ± 2 °C, and the reaction was maintained at this temperature. Samples were taken every hour, and the NCO value of the system was determined by titration using the di-n-butylamine method. After approximately 3 hours, the NCO value reached the theoretical value (approximately 4.5%). Subsequently, a mixture of 11.6 g, 0.1 mol hydroxyethyl acrylate (HEA), and 0.1 g p-methoxyphenol (MEHQ) was added dropwise at a uniform rate over 2 hours at 80 °C. After the addition was complete, the reaction was continued at 80 ± 2 °C, and the characteristic absorption peak of NCO at 2270 cm⁻¹ was monitored by Fourier transform infrared spectroscopy (FT-IR). When this peak essentially disappeared, the reaction was stopped, and the mixture was cooled to room temperature and discharged, yielding a light yellow, transparent, viscous liquid, designated PUA-1. Gel permeation chromatography (GPC) determined its number-average molecular weight (Mn) to be approximately 11,500 and its molecular weight distribution (PDI) to be 1.8.

[0026] Preparation Example 2 (corresponding to PUA-2, with a higher Mn): The procedure was the same as in Preparation Example 1, except that PPG was replaced with poly(1,4-butanediol adipate) (PBA, 200.0 g, 0.10 mol) with Mn = 2000, the IPDI dosage was adjusted to 26.7 g, 0.12 mol, and the HEA dosage was adjusted to 11.6 g, 0.1 mol. The final product PUA-2 had an Mn of approximately 18,500 and a significantly higher viscosity than PUA-1.

[0027] Preparation Example 3 (corresponding to PUA-3, with lower Mn): The procedure was the same as in Preparation Example 1, except that PPG was replaced with polytetrahydrofuran (PTMG, 200.0 g, 0.50 mol) with Mn=400, the amount of IPDI was adjusted to 122.4 g and 0.55 mol, and the amount of HEA was adjusted to 16.24 g and 0.14 mol. The final product PUA-3 had an Mn of approximately 6,800.

[0028] Preparation Examples 1-3 show that by selecting diols with different molecular weights and adjusting the feed ratio of isocyanate to hydroxy acrylate, polyurethane acrylate prepolymers with Mn in the range of 6,800 to 18,500 can be stably obtained. Their flexible main chain structure is the basis for imparting good elasticity and initial tack to the final pressure-sensitive adhesive layer, which is fundamentally different from the rigid epoxy or polyester acrylate oligomers used for insulating coatings in the prior art.

[0029] (2) Preparation and performance verification of acrylate UV pressure-sensitive adhesive.

[0030] First, the general method for preparing the adhesive solution is as follows: Under a light-protected environment, according to the formula in Table 1, add the weighed acrylate diluent monomer, adhesion promoter (P-1M), chain transfer agent, tackifying resin (pre-dissolved in part of the monomer), and leveling agent to a mixing tank in sequence, and stir at 500 rpm for 30 minutes to ensure thorough and uniform dispersion, obtaining the first mixture. Then, add the photoinitiator (TPO, ITX, 184), and continue stirring until completely dissolved (approximately 15-30 minutes), obtaining a clear or uniformly dispersed second mixture. Finally, slowly add the polyurethane acrylate prepolymer (PUA), increase the stirring speed to 800-1000 rpm, and continue stirring at 30±2℃ for 2 hours to ensure uniform mixing. Filter through a 400-mesh filter to obtain the UV pressure-sensitive adhesive solution. Temperature control and light protection are crucial throughout the entire process.

[0031] Secondly, the tape preparation and testing method: The above-mentioned adhesive solution was applied to a 50µm thick blue PET film with a wet adhesive thickness of 30µm using a precision coating machine. A 25µm thick release film was then applied, or a 25µm blue PET film with 33µm wet adhesive applied to both sides, with a 25µm transparent PET corona-treated side applied to one side and a 25µm PET silicone release film applied to the other side. Subsequently, under a nitrogen protective atmosphere (oxygen concentration <500ppm), the coated film was passed through a UV curing device at a speed of 3m / min. The device was equipped with a 395nm LED surface light source with an irradiation intensity of 100mW / cm² and an exposure time of 3 seconds (cumulative energy 300mJ / cm²). After curing, the release film was removed, yielding the battery cell adhesive tape sample.

[0032] The main performance testing standards are as follows: Initial tack: GB / T4852-2002, inclined plane rolling ball method.

[0033] 180° peel strength: GB / T2792-2014, peel speed 300mm / min.

[0034] Test dynamic shear strength: GB / T7124-2008, test temperatures are 25℃ and 60℃ respectively, load is 500g, record failure time or calculate strength.

[0035] Adhesion after humid heat aging: After placing the sample in a constant temperature and humidity chamber at 85℃ and 85% relative humidity for 168 hours, remove it and allow it to return to room temperature. Perform a cross-cut test (1mm spacing) according to GB / T9286-1998 to evaluate the adhesion grade (0B-5B, 5B is the best).

[0036] The formulations and performance data of the examples and comparative examples are shown in Table 1 below.

[0037] Table 1: Formulations and Key Parameters of Examples and Comparative Examples (Unit: Parts by Weight) Table 2: Test Results of Adhesive Tape Performance Examples 2 (10 parts, lower limit) and 3 (30 parts, upper limit) show that within this prepolymer content range, the tapes maintain excellent pressure-sensitive adhesion (peel force >13N / 25mm) and significantly better heat resistance than Comparative Example 4 (60℃ shear strength >3.5MPa vs. 1.7MPa). Below this range (experiments not listed), insufficient cohesive strength and deteriorated high-temperature performance occur; above this range, excessive viscosity affects the coating process.

[0038] Verification of endpoints and key components regarding the composition ratio of acrylate dilution monomers: Endpoints for bifunctional monomer content: Example 4 (HDDA approximately 3% of the diluted monomer, close to the 5% lower limit) showed a decrease in 60°C shear strength (2.9 MPa), demonstrating that 5% is the critical point for maintaining basic heat resistance. Example 5 (HDDA 12%, close to the 25% upper limit) exhibited the best heat resistance (5.6 MPa), but initial tack was sacrificed (ball size 10), indicating that this upper limit is reasonable in balancing adhesion and heat resistance.

[0039] Necessity of functional monomers: Comparative Example 1 (without P-1M) had acceptable initial peel strength, but its adhesion (1B) completely failed after aging in damp heat. This strongly demonstrates that even a small amount (0.5-5%) of phosphorus / carboxyl functional monomers is essential for maintaining durable metal adhesion in the harsh environment of batteries.

[0040] Necessity of bifunctional monomers: The adhesive layer of Comparative Example 3 (without HDDA) failed rapidly at 60°C (0.9MPa), which could not meet the requirements of the battery cell application scenario. This proves that 5-25% bifunctional monomers are crucial for building a moderate crosslinking network and obtaining high temperature creep resistance.

[0041] Regarding the verification of the specific ratio of photoinitiator: Examples 1 (2:1:1) and 7 (1:1:2) both exhibited excellent overall performance within the ratio range listed in claim 4. However, Comparative Example 5 (using only TPO), even with increased dosage, still showed problems of incomplete curing (sticky surface) and poor durability. This confirms that the combination of TPO, ITX, and 184 produces a synergistic effect, which is key to achieving rapid, uniform, and thorough curing, thereby obtaining stable performance.

[0042] Effect of chain transfer agent: Compared with Example 1, Example 6 (without C12-SH) showed an observable decrease in heat resistance, demonstrating the positive effect of chain transfer agent on improving the toughness, uniformity and environmental resistance of the adhesive layer.

[0043] The prepolymer is irreplaceable: The tape of Comparative Example 2 (which completely replaced PUA-1 with rigid epoxy acrylate oligomer A) almost lost its pressure sensitivity (peel force was only 6.0 N / 25 mm). This is consistent with the goal of pursuing a high-hardness insulating coating in the background technology CN117229744A, but it completely deviates from the application purpose of the "pressure-sensitive adhesive" of this invention, thus forming a clear distinction from this invention in terms of use and effect.

[0044] Therefore, Comparative Example 4 (commercially available solvent-based adhesive) represents the current state of the technology that needs improvement. All embodiments of this invention have achieved more than double the improvement in the core high-temperature reliability indicator (60°C shear strength), while completely eliminating VOC emissions, representing significant technological progress.

[0045] Based on the same inventive concept, this embodiment of the invention also provides a battery cell bonding tape. The UV pressure-sensitive adhesive prepared in Example 1 is coated and cured onto a 25μm thick blue polyethylene terephthalate (PET) film using the aforementioned method, forming a pressure-sensitive adhesive layer with a thickness of approximately 20μm, thus preparing the battery cell bonding tape. This tape can firmly adhere to the surface of the battery cell's aluminum shell at room temperature, and its peel strength is tested to reach 15.5N / 25mm. Even after long-term storage at a high temperature of 60℃, the tape did not exhibit any curling or detachment. Its adhesion performance is far superior to the commercially available product in Comparative Example 4, significantly improving the long-term safety and reliability of the battery cell.

[0046] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. An acrylic UV pressure-sensitive adhesive for bonding films to battery cells, characterized in that, It consists of the following components in parts by weight: 10 to 30 parts of polyurethane acrylate prepolymer, 60 to 140 parts of acrylate diluent monomer, 1 to 5 parts of photoinitiator, 0.5 to 3 parts of adhesion promoter, 0.05 to 0.5 parts of chain transfer agent, 2 to 10 parts of tackifying resin, and 0 to 5 parts of additives. The acrylate diluent monomers include monofunctional acrylate monomers, difunctional acrylate monomers, and phosphorus- or carboxyl-containing acrylate functional monomers; based on the total mass of the acrylate diluent monomers as 100%, the content of the monofunctional acrylate monomers is 70% to 95%, the content of the difunctional acrylate monomers is 5% to 25%, and the content of the phosphorus- or carboxyl-containing acrylate functional monomers is 0.5% to 5%.

2. The pressure-sensitive adhesive according to claim 1, characterized in that, The polyurethane acrylate prepolymer is prepared by a method comprising the following steps: reacting a polyether diol or polyester diol with a number-average molecular weight of 400 to 2000 with a diisocyanate under the action of a catalyst to obtain an isocyanate-terminated prepolymer, which is then reacted with a hydroxy acrylate monomer to end-cap the prepolymer; the number-average molecular weight of the polyurethane acrylate prepolymer is 5000 to 20000.

3. The pressure-sensitive adhesive according to claim 1, characterized in that, The monofunctional acrylate monomer is selected from at least one of isooctyl acrylate, isobornyl acrylate, lauryl acrylate, and benzyl acrylate; the difunctional acrylate monomer is selected from at least one of 1,6-hexanediol diacrylate, dipropylene glycol diacrylate, and tricyclodecanediethanol diacrylate; the phosphorus- or carboxyl-containing acrylate functional monomer is selected from at least one of hydroxyethyl acrylate phosphate, hydroxyethyl methacrylate phosphate, and acrylic acid.

4. The pressure-sensitive adhesive according to claim 1, characterized in that, The photoinitiator is a mixture of 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 2-isopropylthioxanthone, and 1-hydroxycyclohexylphenyl ketone, and the mass ratio of the three is 1:1:1, 2:1:1, 3:1:1, 1.5:1:1, or 2:1:1.

5.

5. The pressure-sensitive adhesive according to claim 1, characterized in that, The chain transfer agent is at least one of isooctyl mercaptoacetate, dodecyl mercaptoethanol, or isooctyl 3-mercaptopropionate.

6. A method for preparing an acrylic UV pressure-sensitive adhesive for battery cell bonding, the method being used to prepare the pressure-sensitive adhesive according to any one of claims 1 to 5, characterized in that, The preparation method includes the following steps: S1, mix the acrylate diluent monomer, adhesion promoter, chain transfer agent, tackifying resin and optional additives according to the formula, stir and disperse evenly to obtain the first mixture; S2, add photoinitiator to the first mixture and stir until completely dissolved to obtain the second mixture; S3, add polyurethane acrylate prepolymer to the second mixture, stir and mix evenly, filter, and the acrylate UV pressure-sensitive adhesive is obtained.

7. The preparation method according to claim 6, characterized in that, The polyurethane acrylate prepolymer is prepared by the following steps: S31, dehydrate polyether diol or polyester diol at 110°C to 130°C under vacuum for 1 to 3 hours; S32, the dehydrated diol is cooled to 60 to 70 degrees Celsius, diisocyanate and catalyst are added, and the reaction is carried out at 70 to 80 degrees Celsius until the NCO content of the system reaches the theoretical value, to obtain the terminal isocyanate group prepolymer; S33, add hydroxy acrylate monomer and polymerization inhibitor to the terminal isocyanate prepolymer, and react at 75°C to 85°C until the NCO characteristic peak disappears to obtain the polyurethane acrylate prepolymer.

8. The preparation method according to claim 6, characterized in that, In step S3, the stirring and mixing are carried out under light-protected conditions, with a mixing temperature of 25 degrees Celsius to 40 degrees Celsius and a mixing time of 1 hour to 3 hours.

9. A battery cell bonding tape, characterized in that, It includes a substrate layer and a pressure-sensitive adhesive as described in any one of claims 1 to 5 coated on at least one side of the substrate layer.

10. The cell-mounting tape according to claim 9, characterized in that, The substrate layer is a polyethylene terephthalate film, a polyimide film, or a polyolefin film, with a thickness of 10 micrometers to 50 micrometers; the pressure-sensitive adhesive layer has a thickness of 10 micrometers to 30 micrometers.

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