Photo-crosslinking rapidly-curable battery binder and preparation method thereof

Abstract

The invention provides a photo-crosslinking type battery binder capable of being rapidly cured and a preparation method of the photo-crosslinking type battery binder. The method comprises the following steps: (1) dissolving hydroxyl-terminated hydrogenated butyronitrile in an organic solvent to obtain a solution A; (2) adding diisocyanate and a catalyst into the solution A for reaction to obtain a solution B; (3) adding polyol into the solution B for reaction to obtain a solution C; and (4) adding an acrylic acid compound into the solution C for reaction to obtain a product precursor D, and illuminating the product precursor D for 4-6 minutes to obtain the photo-crosslinking type battery binder capable of being quickly cured. According to the invention, a stable cross-linking system which can be rapidly cured under the illumination condition is constructed, excellent bonding strength and good polarity are retained, and meanwhile, the adhesive also has good mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of battery materials technology, and in particular to a photocrosslinking type rapidly curable battery binder and its preparation method. Background Technology

[0002] In recent years, high-nickel ternary lithium batteries have become a research hotspot due to their high theoretical specific capacity (275 mAh / g), high operating potential, and low cost, and are considered one of the most promising lithium-ion power batteries. Although LiNi, a ternary oxide material with a layered structure... x Co y Mn z O2 (NCM) materials offer advantages such as high specific capacity and low cost, but they still suffer from drawbacks such as low capacity retention and poor thermal stability. During charge and discharge, NCM materials undergo a crystal phase transformation (layered → spinel → rock salt phase) at voltages of 3.7V, 4.0V, and 4.2V. This transformation from layered to spinel phase is often accompanied by the release of lattice oxygen, leading to shrinkage of the cell volume and interlayer spacing, disrupting the material lattice, and reducing structural stability. Furthermore, with the extraction and insertion of lithium ions, NCM materials experience a 3.9% volume change, forming propagating cracks within the particles. This increases the battery's polarization, and as charge and discharge continue, the internal polarization intensifies, crack propagation accelerates, and ultimately, material breakage or even detachment occurs, exacerbating interfacial side reactions and accelerating capacity decay. Using high-performance binders is the simplest method to improve battery structural stability and electrochemical performance.

[0003] Commonly used binders on the market include polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), and carboxymethyl cellulose (CMC) / styrene-butadiene emulsion (SBRL) blends. While PVDF exhibits relatively stable electrochemical performance in lithium cobalt oxide and lithium iron phosphate materials, its weak van der Waals forces bind electrode components together, and its high swelling ratio in the electrolyte leads to degradation under high temperature and pressure, making it insufficient for high-energy-density applications. As a representative of water-soluble binders, CMC improves bonding strength by forming hydrogen bonds, chemical bonds, and ion-dipole bonds with the electrode material. SBRL provides good mechanical properties to the binder system; however, water as a solvent is difficult to dry, and residual moisture easily reacts with NCM materials and the electrolyte, affecting the material's morphology and surface composition, and increasing irreversible capacity loss.

[0004] Therefore, the development of efficient binders with both bonding strength and mechanical strength has become a current research hotspot. Although a lot of research has been done on the above issues, some problems still exist: (1) Some binders are mainly crosslinked by hydrogen bonds, and the binders have weak high temperature and high pressure resistance. They are easily degraded under extreme conditions such as high temperature and high pressure, resulting in side reactions of the electrode; (2) Traditional thermal crosslinking and other crosslinking methods are difficult to react, consume a lot of energy, and the crosslinked structure is unstable; (3) The solvents of binders are usually N-methylpyrrolidone (NMP), chlorobenzene, xylene, etc. These solvents have high boiling points, and a long time and high temperature drying process is required in the preparation of the electrode, which greatly increases the cost of electrode preparation and the pollution to the environment; (4) The residual solvent of water-soluble binders will accelerate the precipitation of transition metals, causing irreversible capacity loss of the battery; (5) The mechanical strength of the binder is not enough to relieve the stress generated by the expansion of the electrode material. Summary of the Invention

[0005] This invention aims to at least partially address one of the technical problems in the prior art. Therefore, one objective of this invention is to provide a photocrosslinking, rapidly curable battery binder and its preparation method, to solve the problems existing in batteries using commercial binders such as PVDF, including complex crosslinking methods, low strength, insufficient mechanical strength, poor high-pressure resistance, and long drying times and high temperatures.

[0006] In a first aspect, the present invention provides a method for preparing a photocrosslinking, rapidly curable battery adhesive, comprising: (1) Hydroxyl-terminated hydrogenated butyronitrile is dissolved in an organic solvent to obtain solution A.

[0007] (2) Add diisocyanate and catalyst to solution A to react and obtain solution B.

[0008] (3) Add a polyol to the solution B to react and obtain solution C.

[0009] (4) Add acrylic compounds to the solution C to react, and irradiate the resulting product precursor D with light for 4-6 minutes to obtain a photocrosslinked battery adhesive that can be cured quickly.

[0010] The method for preparing the photocrosslinked, rapidly curable battery adhesive provided by this invention utilizes hydroxyl-terminated hydrogenated butadiene-acrylonitrile liquid rubber with excellent adhesive properties and containing polar groups such as cyano groups as the soft segment and diisocyanate as the hard segment. This constructs a stable crosslinking system capable of curing under ultraviolet light, retaining excellent adhesive strength and good polarity while also exhibiting good mechanical properties. Under photocuring crosslinking conditions, using anhydrous tetrahydrofuran or similar solvents significantly reduces the drying time and temperature during the application of the adhesive in electrode manufacturing, improving production efficiency and reducing energy consumption.

[0011] In some embodiments of the present invention, in step (1), the number average molecular weight of the hydroxyl-terminated hydrogenated butyronitrile is 5000-50000. By controlling the number average molecular weight of the hydroxyl-terminated hydrogenated butyronitrile within the above range, the viscosity of the prepared binder can be controlled, thereby giving it optimal dispersion performance.

[0012] In some embodiments of the present invention, the organic solvent includes at least one of tetrahydrofuran (THF), chlorobenzene, xylene, dichloromethane, and N,N-dimethylformamide, preferably tetrahydrofuran.

[0013] In some embodiments of the present invention, the mass fraction of the hydroxyl-terminated hydrogenated butyronitrile in solution A is 1%-40%.

[0014] In some embodiments of the present invention, the molar ratio of -NCO in the diisocyanate to -OH in the hydroxyl-terminated hydrogenated butyronitrile is (0.1-20):1. A molar ratio of -NCO in the diisocyanate to -OH in the hydroxyl-terminated hydrogenated butyronitrile within the above range ensures the smooth progress of the reaction and controls the degree of crosslinking of the subsequent products.

[0015] In some embodiments of the present invention, the catalyst is selected from dibutyltin dilaurate, and the amount of the catalyst added is 0.02-5.0% of the mass of the hydroxyl-terminated hydrogenated butyronitrile.

[0016] In some embodiments of the present invention, the reaction in step (2) is carried out under an inert atmosphere, the temperature of the reaction is 50-70°C, and the reaction time is 2h-12h.

[0017] In some embodiments of the present invention, the molar ratio of the polyol added in step (3) to the diisocyanate in step (2) is (0.1-20):1. Maintaining the molar ratio of the polyol to the diisocyanate within the above range ensures the smooth progress of the reaction and controls the degree of crosslinking of the subsequent products.

[0018] In some embodiments of the present invention, in step (3), the temperature of the reaction is 40-60°C and the reaction time is 1.5h-6h.

[0019] In some embodiments of the present invention, the polyol includes one or more of ethylene glycol, propylene glycol, 1,4-butanediol, 2,2-dimethylolbutanol, and neopentyl glycol.

[0020] In some embodiments of the present invention, the molar ratio of the acrylic compound added in step (3) to the diisocyanate in step (2) is (0.1-20):1. Maintaining the molar ratio of the acrylic compound to the diisocyanate within the above range ensures the smooth progress of the reaction and controls the degree of crosslinking of the subsequent products.

[0021] In some embodiments of the present invention, in step (4), the temperature of the reaction is 40-60°C and the reaction time is 1.5h-6h.

[0022] In some embodiments of the present invention, the acrylic compound includes one or more of methyl methacrylate, aminoacrylic acid, epoxy acrylate, and isooctyl acrylate, preferably aminoacrylic acid.

[0023] In a second aspect, this invention provides a photocrosslinking, rapidly curable battery binder prepared using the method described above. This photocrosslinking, rapidly curable battery binder can significantly improve the strength of battery electrodes, extend their service life, and reduce their production costs.

[0024] In a third aspect, the present invention provides a method for preparing an electrode sheet, comprising: mixing the battery binder precursor, active material, and conductive agent as described in the above-mentioned method for preparing a photocrosslinkable and rapidly curable battery binder, applying the mixture to a current collector, and then curing it by light and drying it.

[0025] In some embodiments of the present invention, the mass ratio of the active material, the battery binder precursor, and the conductive agent is 90:(1-7):(1-7).

[0026] In some embodiments of the present invention, the power of the illumination is 50W-200W, and the illumination time is 1min-60min.

[0027] In some embodiments of the present invention, the illumination is selected from ultraviolet irradiation.

[0028] In some embodiments of the present invention, when the electrode is a positive electrode, the active material used is a positive electrode active material, such as lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, high-nickel ternary materials, etc.

[0029] In a fourth aspect, the present invention provides an electrode sheet prepared by the above-described method. This electrode sheet exhibits excellent mechanical strength, a long service life, and superior electrical properties.

[0030] Preferably, the electrode is a positive electrode.

[0031] In a fifth aspect, the present invention provides a battery comprising the aforementioned electrodes. This battery exhibits excellent rate performance and cycle performance.

[0032] The present invention has at least the following beneficial effects: (1) The photocrosslinking type fast-curing battery binder prepared by the present invention has a green and short crosslinking method and a stable crosslinking structure. This crosslinking structure gives it excellent adhesion and mechanical properties. The binder is used to prepare positive electrode sheets such as NCM811, which greatly shortens the drying time and temperature required in the preparation process.

[0033] (2) The binder prepared in this invention, when used as a binder for the positive electrode of a lithium-ion battery to assemble a lithium-ion secondary battery, exhibits high cycle stability and good electrochemical performance, enabling positive electrodes such as NCM811 to achieve long cycle life and excellent rate performance (100 cycles, 0.2C, 2.5V-4.7V) under high voltage. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0035] Figure 1 These are the peel strength results of the positive electrode sheets of Groups 1-4 of this invention.

[0036] Figure 2 These are the infrared spectra of HHTBN, BPC-HHTBN, and PC-HHTBN from Embodiment 1 of the present invention.

[0037] Figure 3 This is a graph showing the linear relationship between the battery peak current and the scan rate in Comparative Example 2 of this invention.

[0038] Figure 4 This is a linear relationship graph between the battery peak current and the scan rate in Embodiment 2 of the present invention.

[0039] Figure 5 The graph shows the number of cycles and rate of the button cells of Example 2 and Comparative Example 4 after 500 cycles at 2.5-4.0V and 1C.

[0040] Figure 6 This is a graph showing the number of cycles and rate of operation of the button cells of Examples 2, 2, 3 and 4 after 100 cycles at 2.5-4.3V and 0.2C.

[0041] Figure 7 This is a graph showing the number of cycles and rate of operation of the button cells of Example 2, Comparative Example 2, and Comparative Example 4 after 100 cycles at 2.5-4.7V and 0.2C. Detailed Implementation

[0042] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. The invention will now be described with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the invention in any way.

[0043] Example 1 (1) This embodiment provides a photocrosslinking type battery adhesive that can be cured quickly, and its specific preparation process is as follows: a. Dissolve 0.5 mmol of hydroxyl-terminated hydrogenated butadiene-acrylonitrile liquid rubber with a number average molecular weight of 10000 in anhydrous THF to obtain a solution A with a hydroxyl-terminated hydrogenated butadiene-acrylonitrile concentration of 10 wt%. Solution A is named HHTBN.

[0044] b. Add 2 mmol of diisocyanate and 10 mg of catalyst dibutyltin dilaurate to solution A, and react for 6 h at 60 °C under a nitrogen atmosphere to obtain solution B.

[0045] c. Add 0.5 mmol of 2,2-dihydroxymethylbutanol to solution B and react at 50°C for 2 h to obtain solution C.

[0046] d. Add 5 mmol of aminoacrylic acid to solution C and react at 50 °C for 2 h to prepare product precursor D (BPC-HHTBN).

[0047] BPC-HHTBN was irradiated with 100W ultraviolet light for 5 minutes to obtain a photocrosslinking type fast-curing lithium-ion battery adhesive (PC-HHTBN).

[0048] (2) This embodiment provides a positive electrode sheet, and the specific preparation process is as follows: Weigh 2.4g LiFePO4 and 0.3g conductive carbon black and mix them evenly. Add 3g of the precursor product BPC-HHTBN prepared in step (1) to the mixture and stir in an emulsifier for 40min to form a uniform positive electrode slurry for later use. Coat the slurry evenly on carbon-coated aluminum foil using a coating machine. Irradiate the electrode under ultraviolet light for 5min. Transfer the electrode to a vacuum oven at 50℃ and bake for 3h. Roll press and punch to obtain a circular positive electrode.

[0049] (3) This embodiment provides a battery, and the specific preparation process is as follows: After the electrodes were dried in a vacuum oven at 50°C for 30 min, they were paired with lithium metal and assembled into coin cells in a glove box under a dry argon atmosphere (oxygen value < 0.1 ppm). The electrolyte was 1.2 M LiPF6 dissolved in a mixed solvent of EC:DMC:EMC = 1:1:1 %vol, and then mixed with FEC at a ratio of 9:1. The separator was Celgard 2500 PP membrane.

[0050] Example 2 (1) This embodiment provides a photocrosslinking type fast-curing battery adhesive, which is the same as that in Example 1.

[0051] (2) This embodiment provides a positive electrode sheet, and the specific preparation process is as follows: Weigh 1.8g of NCM811 positive electrode active material and 0.1g of conductive carbon black and mix them evenly. Add 1g of BPC-HHTBN binder prepared in step (1) to the mixture and stir in an emulsifier for 40min to form a uniform positive electrode slurry for later use. Coat the slurry evenly on carbon-coated aluminum foil using a coating machine. Irradiate the electrode sheet under ultraviolet light for 5min and transfer the electrode sheet to a vacuum oven at 50℃ for 3h to obtain the positive electrode sheet.

[0052] (3) This embodiment provides a battery, and the specific preparation process is the same as that in Embodiment 1.

[0053] Comparative Example 1 (1) This comparative example provides a PVDF adhesive, and the specific preparation process is as follows: Weigh 5g of PVDF powder into a 200ml beaker, add 100g of N-methylpyrrolidone (NMP) solution to form a 5wt% binder solution.

[0054] (2) This comparative example provides a positive electrode sheet, and the specific preparation process is as follows: Weigh 2.4g LiFePO4 and 0.3g conductive carbon black and mix them evenly. Add 6g of the PVDF binder prepared in step (1) to the mixture and stir in an emulsifier for 40min to form a uniform positive electrode slurry for later use. Coat the slurry evenly on carbon-coated aluminum foil using a coating machine and transfer the electrode to an 80℃ vacuum oven to dry for 12h.

[0055] (3) This comparative example provides a battery, and the specific preparation process is the same as that in Example 1.

[0056] Comparative Example 2 (1) This comparative example provides a PVDF adhesive, and the specific preparation process is the same as that of comparative example 2.

[0057] (2) This comparative example provides a positive electrode sheet, and the specific preparation process is as follows: Weigh 1.8g of NCM811 positive electrode material and 0.1g of conductive carbon black and mix them evenly. Add 2g of the PVDF binder prepared in step (1) to the mixture and stir in an emulsifier for 40min to form a uniform positive electrode slurry for later use. Coat the slurry evenly on carbon-coated aluminum foil using a coating machine. Transfer the electrode to an 80℃ vacuum oven and bake for 12h to obtain the positive electrode. Roll press and punch to obtain a circular positive electrode.

[0058] (3) This comparative example provides a battery, and the specific preparation process is the same as that in Example 1.

[0059] Comparative Example 3 (1) The adhesive used in Comparative Example 3 was Solution A (HHTBN) of Example 1.

[0060] (2) This comparative example provides a positive electrode sheet, and the specific preparation process is the same as that in Example 1.

[0061] (3) This comparative example provides a battery, and the specific preparation process is the same as that in Example 1.

[0062] Comparative Example 4 (1) The binder used in Comparative Example 4 was the precursor product (BPC-HHTBN) obtained in step d of Example 1.

[0063] (2) This comparative example provides a positive electrode sheet, and the specific preparation process is as follows: Weigh 1.8g of NCM811 positive electrode active material and 0.1g of conductive carbon black and mix them evenly. Add 1g of BPC-HHTBN binder prepared in step (1) to the mixture and stir in an emulsifier for 40min to form a uniform positive electrode slurry for later use. Coat the slurry evenly on carbon-coated aluminum foil using a coating machine. Transfer the electrode to a vacuum oven at 50℃ and bake for 3h to obtain the positive electrode.

[0064] (3) This comparative example provides a battery, and the specific preparation process is the same as that in Example 2.

[0065] The binder and battery performance of the examples and comparative examples were measured.

[0066] 1) Testing of the peel strength of the positive electrode sheet Group 1: Using the positive electrode sheet of Comparative Example 2; Group 2: Using the positive electrode sheet of Comparative Example 3; Group 3: Using the positive electrode sheet of Comparative Example 4; Group 4: Using the positive electrode sheet of Example 2; The positive electrode sheet was fixed with tinplate as the backing plate and tightly bonded to the surface of the positive electrode sheet using 20 mm 3M tape. A 180° peel test of the tape was conducted using a ZwickRoell ZL7000 universal tensile testing machine. The peel speed was 0.5 mm / s. -1 The peel strength results for the positive electrode sheets of groups 1-4 are shown in the figure. Figure 1 .from Figure 1 It can be seen that the average peel strengths of NCM811 / HHTBN electrode sheets, BPC-HHTBN electrode sheets, and NCM811 / PC-HHTBN electrode sheets are 0.360 N / mm, 0.420 N / mm, and 0.445 N / mm, respectively, which are higher than the average peel strength of NCM811 / PVDF (0.285 N / mm). This indicates that the adhesives prepared with HHTBN as the substrate have higher adhesion than commercial adhesives.

[0067] 2) The infrared spectra of PC-HHTBN were obtained after irradiating HHTBN, BPC-HHTBN, and BPC-HHTBN with 100W ultraviolet light for 5 minutes, as shown in the figure. Figure 2 As shown, from Figure 2 It can be known that 1720cm -1 The absorption peak at 810 cm⁻¹ represents the symmetric stretching vibration peak of the C=O bond in the imide ring, proving that the polymerization reaction proceeded successfully. -1 The absorption peak at that point represents the absorption peak of the C=C bond. After illumination, the absorption peak of C=C decreases significantly, proving the successful preparation of the photocrosslinking adhesive.

[0068] 3) The wettability of the positive electrode sheets of Examples 2, 2, 3, and 4 was measured using electrolyte as the medium, and the contact process of the test droplets was recorded using a contact angle meter. The results showed that the contact angle of Comparative Example 2 was 13.3°, that of Comparative Example 3 was 13.4°, that of Comparative Example 4 was 11.5°, and that of Example 2 was 10.8°. This indicates that the binder of the present invention is beneficial for increasing electrolyte wettability and maintaining stable lithium-ion diffusion capability.

[0069] 4) The 5wt% PVDF binder solution of Comparative Example 1 was spread out and dried to form a film, which was denoted as PVDF film; the BPC-HHTBN of Example 1 was spread out and irradiated with ultraviolet light at 100W for 5 minutes to obtain PC-HHTBN film. The PVDF film and PC-HHTBN film were immersed in 15ml of electrolyte, and the changes in the mass and morphology of the film before and after immersion were observed. The test results are shown in Table 1.

[0070] Table 1

[0071] As shown in Table 1, after 7 days of soaking, the PVDF membrane exhibited significant gelation in the electrolyte solvent, with a swelling rate as high as 46.8%, while the PC-HHTBN membrane showed no significant swelling, with a swelling rate of 11.0%. This indicates that the PC-HHTBN membrane has lower electrolyte swelling, which can avoid structural damage caused by excessive swelling and effectively improve the structural stability of the positive electrode.

[0072] 5) The electrochemical activity and redox potential of the coin cells obtained in Example 2 and Comparative Example 2 were analyzed using a CHI650E electrochemical workstation. The scanning voltage range was 2.5 V–4.7 V, and the scanning rate was 0.1 mV s. -1 The test temperature was kept constant at 25℃. The cyclic voltammetry curves at different scan rates and the linear relationship between peak current and scan rate for different samples are shown in the figure. Figure 3 and Figure 4 As shown.

[0073] from Figure 3 and Figure 4 It can be seen that the slope of the square root of the scan rate (v1 / 2) versus the peak current (Ip) plot of the NCM811 / PC-HHTBN system is larger, indicating that the Li in this system... + Its diffusion ability is stronger than that of NCM / PVDF.

[0074] 6) The long-cycle performance and rate performance of the batteries of Example 2, Comparative Example 2, Comparative Example 3, and Comparative Example 4 in different systems were tested.

[0075] The constant current charge-discharge performance of the battery was tested using the LAND CT3002A battery testing system at a constant temperature of 25℃.

[0076] The coin cells of Example 2 and Comparative Example 4 were cycled 500 times in an LFP system at 2.5-4.0V and 1C, and their rate performance was tested, yielding charge-discharge curves and rate curves. Figure 5 As shown.

[0077] In Example 2, Comparative Examples 2, 3, and 4, the coin cells were cycled 100 times at 2.5-4.3V and 0.2C in an NCM811 system, and their rate performance was tested, yielding charge-discharge curves and rate curves. Figure 6 As shown.

[0078] The coin cells of Examples 2, 2, 3, and 4 were cycled 100 times at 2.5-4.7V and 0.2C, and their rate performance was tested, yielding charge-discharge curves and rate curves. Figure 7 As shown.

[0079] Specific test results are shown in Table 2 and... Figures 5-7 .

[0080] Table 2

[0081] From Table 2 and Figure 5-7 The initial discharge specific capacities of the NCM811 / PVDF, NCM811 / HHTBN, NCM811 / BPC-HHTBN, and NCM811 / PC-HHTBN half-cells are 181.2 mAh / g, 190 mAh / g, 190.8 mAh / g, and 182.2 mAh / g, respectively. After 100 cycles, the capacity retention rates of the NCM811 / PVDF, NCM811 / HHTBN, NCM811 / BPC-HHTBN, and NCM811 / PC-HHTBN half-cells are 82.4%, 85.2%, 88.8%, and 91.9%, respectively. Compared to the NCM811 / PVDF, NCM811 / HHTBN, and NCM811 / BPC-HHTBN half-cells, the NCM811 / PC-HHTBN half-cell exhibits better discharge specific capacity and capacity retention. After increasing the cutoff voltage to 4.7V, the NCM811 / PC-HHTBN half-cell also exhibited superior cycle performance.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a photocrosslinking, rapidly curable battery adhesive, characterized in that, include: (1) Hydroxyl-terminated hydrogenated butyronitrile is dissolved in an organic solvent to obtain solution A; (2) Add diisocyanate and catalyst to solution A to react and obtain solution B; (3) Add a polyol to the solution B to react and obtain solution C; (4) Add acrylic compounds to the solution C to react, and irradiate the resulting product precursor D with light for 4-6 minutes to obtain a photocrosslinked battery adhesive that can be cured quickly.

2. The method according to claim 1, characterized in that, In step (1), the number average molecular weight of the hydroxyl-terminated hydrogenated butyronitrile is 5000-50000; And / or, the organic solvent includes at least one of tetrahydrofuran, chlorobenzene, xylene, dichloromethane, and N,N-dimethylformamide, preferably tetrahydrofuran; And / or, the mass fraction of the hydroxyl-terminated hydrogenated butyronitrile in solution A is 1%-40%.

3. The method according to claim 1, characterized in that, The molar ratio of -NCO in the diisocyanate to -OH in the hydroxyl-terminated hydrogenated butyronitrile is (0.1-20):1; And / or, the catalyst is selected from dibutyltin dilaurate, and the amount of the catalyst added is 0.02-5.0% of the mass of the hydroxyl-terminated hydrogenated butyronitrile; And / or, the reaction in step (2) is carried out under an inert atmosphere, the temperature of the reaction is 50-70°C, and the reaction time is 2h-12h.

4. The method according to claim 1, characterized in that, The molar ratio of the polyol added in step (3) to the diisocyanate in step (2) is (0.1-20):1; And / or, in step (3), the reaction temperature is 40-60℃ and the reaction time is 1.5h-6h; And / or, the polyol includes one or more of ethylene glycol, propylene glycol, 1,4-butanediol, 2,2-dimethylolbutanol, and neopentyl glycol.

5. The method according to claim 1, characterized in that, The molar ratio of the acrylic compound added in step (3) to the diisocyanate in step (2) is (0.1-20):1; And / or, in step (4), the temperature of the reaction is 40-60°C and the reaction time is 1.5h-6h; And / or, the acrylic compounds include one or more of methyl methacrylate, aminoacrylic acid, epoxy acrylate, and isooctyl acrylate.

6. A photocrosslinking, rapidly curing battery adhesive, characterized in that, It is prepared by any one of the methods described in claims 1-5.

7. A method for preparing an electrode sheet, characterized in that, include: In the preparation method of the photocrosslinkable fast-curing battery binder according to any one of claims 1-5, the product precursor D is mixed with the active material and the conductive agent, applied to the current collector, and then cured by light and dried.

8. The method according to claim 7, characterized in that, The mass ratio of the active material, the battery binder precursor, and the conductive agent is 90:(1-7):(1-7). And / or, the power of the illumination is 50W-200W, and the illumination time is 1min-60min.

9. An electrode sheet, characterized in that, Prepared using the method described in claim 7 or 8; Preferably, the electrode is a positive electrode.

10. A battery, characterized in that, Includes the electrode as described in claim 9.

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