Preparation method and application of conductive polymer adhesive

Abstract

The invention relates to a preparation method and application of a conductive polymer adhesive, and belongs to the technical field of adhesive preparation, and the preparation method specifically comprises the following preparation steps: S1, heating modified cellulose, styrene and acrylate to 60-90 DEG C, stirring, and adding an initiator for reaction to obtain an adhesive precursor; s2, preparing a porous zinc oxide-carbon conductive filler; and S3, adding the conductive filler into the adhesive precursor, adding the defoaming agent, and stirring to obtain the conductive polymer adhesive. According to the scheme, the adhesive precursor solution is prepared by using the modified cellulose, the monomer styrene and the acrylate material, and the styrene-acrylate copolymer is generated in the system, so that the adhesive is endowed with relatively strong adhesion. Meanwhile, a composite material of porous zinc oxide and graphene is prepared by adopting a template method to serve as a conductive filler, and the conductivity and energy storage performance of the composite material are improved through the high conductivity of graphene and the high specific capacitance of porous zinc oxide.

Description

Technical Field

[0001] This application relates to the technical field of adhesive preparation, and more specifically, to a preparation method and application of a conductive polymer adhesive. Background Art

[0002] In current battery and electrode material technologies, conductive polymer adhesives play a crucial role. However, existing conductive polymer adhesive technologies still have many deficiencies, restricting their applications in high-performance batteries and electrode materials.

[0003] Firstly, traditional conductive polymer adhesives have limitations in adhesion. Many adhesives are difficult to meet the bonding requirements of various materials. Especially when facing complex electrode structures, their adhesion is often insufficient to maintain the long-term stability of the electrodes. This causes the electrodes to easily fall off or the structure to be damaged during the charge and discharge processes of the battery, thus affecting the performance and lifespan of the battery. Secondly, there are bottlenecks in the conductivity of existing conductive polymer adhesives. Although some adhesives already have a certain level of conductivity, their conductive channels are often not optimized enough, resulting in the inability to fully utilize the conductive performance. In addition, the dispersion effect and energy storage performance of conductive fillers such as zinc oxide added during the preparation of some adhesives still need to be improved. This restricts the application of adhesives in high-performance batteries, especially in scenarios requiring high energy density and long cycle life.

[0004] Based on the above statements, this application provides a preparation method and application of a conductive polymer adhesive. Summary of the Invention

[0005] To solve the problems raised in the background art, this application provides a preparation method and application of a conductive polymer adhesive.

[0006] This application provides a preparation method of a conductive polymer adhesive, adopting the following technical scheme:

[0007] A preparation method of a conductive polymer adhesive includes the following preparation steps:

[0008] S1. Mix modified cellulose, monomer styrene, and acrylate materials, raise the temperature of the system to 60 - 90 °C, stir evenly at a rate of 60 - 90 rpm, then add an initiator, and stir and react at a rate of 200 - 500 rpm for 8 - 12 hours to obtain a precursor solution of the adhesive;

[0009] Among them, the initiator is at least one of azobisisobutyronitrile and benzoyl peroxide;

[0010] S2. Use the template method to prepare porous zinc oxide, and add graphene during the process to prepare a porous zinc oxide-carbon conductive filler;

[0011] S3. Add the porous zinc oxide-carbon conductive filler obtained in step S2 to the binder precursor solution obtained in step S1. After stirring evenly, add an antifoaming agent, and continue to stir the system at 1000 - 1200 rpm for 5 - 10 minutes to obtain a conductive polymer binder.

[0012] Among them, the modified cellulose in step S1 is obtained by modifying cellulose with dopamine hydrochloride.

[0013] In the above reaction process, a binder precursor solution is prepared using modified cellulose, monomer styrene, and acrylate materials. With modified cellulose as an emulsifier and in combination with an initiator, the copolymerization of monomer styrene and acrylate materials is promoted, and a styrene-acrylate copolymer is formed in the system for the preparation of subsequent conductive adhesives.

[0014] Furthermore, in step S1, the modified cellulose is specifically prepared by the following steps:

[0015] S11. Add 2-(N-morpholino)ethanesulfonic acid to deionized water, adjust the pH value of the system to 5.5 - 6.7, and stir the system at a rate of 30 - 90 rpm and at room temperature until dissolved to obtain a 2-(N-morpholino)ethanesulfonic acid buffer solution.

[0016] S12. Dissolve carboxymethyl cellulose, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, N-hydroxysuccinimide, and dopamine hydrochloride in the 2-(N-morpholino)ethanesulfonic acid buffer solution, and stir for 24 hours at room temperature and in an inert gas atmosphere to obtain modified cellulose.

[0017] Furthermore, in step S1, the modified cellulose is specifically prepared by the following steps:

[0018] S11. Add 0.5 - 0.8 g of 2-(N-morpholino)ethanesulfonic acid to 30 mL of deionized water, use a NaOH solution to adjust the pH value of the system to 5.5 - 6.7, and stir the system at a rate of 30 - 90 rpm and at room temperature until dissolved to obtain a 2-(N-morpholino)ethanesulfonic acid buffer solution.

[0019] S12. Dissolve carboxymethyl cellulose, 0.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 0.12 g of N-hydroxysuccinimide, and dopamine hydrochloride in 10 mL of the 2-(N-morpholino)ethanesulfonic acid buffer solution, and stir for 24 hours at room temperature and in an inert gas atmosphere to obtain modified cellulose.

[0020] During the above reaction process, carboxymethyl cellulose was modified using dopamine hydrochloride. The amino group on dopamine hydrochloride and the carboxyl group on carboxymethyl cellulose underwent an amidation reaction in the EDC / NHS system, introducing amide groups and catechol groups onto the carboxymethyl cellulose, and the modified cellulose was prepared.

[0021] Further, in step S12, the mass ratio of carboxymethyl cellulose to dopamine hydrochloride is (5 - 8):(0.2 - 0.8).

[0022] Further, in step S1, the mass ratio of the modified cellulose, initiator, monomer styrene, and acrylate material is (0.5 - 2):(0.0001 - 0.0003):(2 - 5):5.

[0023] Further, in step S1, the acrylate material is an acrylate with 1 - 6 carbon atoms in the alkyl group.

[0024] Further, in step S1, the acrylate material is at least one of methyl methacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, or 2 - ethylhexyl acrylate.

[0025] Further, in step S2, the porous zinc oxide - carbon conductive filler is specifically prepared by the following steps:

[0026] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at room temperature, then seal and age at 80 - 90 °C to obtain an aged solution;

[0027] S22. Add graphene to the aged solution and stir at room temperature; then heat the system at 170 - 190 °C for 6 - 8 hours, filter, add the precipitate to a 10 - 30 wt% ammonia aqueous solution, treat for 3 - 6 hours, then wash the precipitate and dry it at 50 - 80 °C for 12 - 24 hours, and then heat it to 300 - 500 °C at a heating rate of 2 - 5 °C per minute and perform annealing treatment for 3 - 4 hours to obtain the porous zinc oxide - carbon conductive filler.

[0028] During the above reaction process, the template method was used to prepare porous zinc oxide, and graphene was added during the process to prepare a composite material of porous zinc oxide and carbon as the conductive filler in the conductive polymer binder. Urea was used as the precipitating agent, and the surfactant was used as the templating agent to form an ordered mesoporous structure through its self - assembly behavior, thereby introducing porosity into zinc oxide. Subsequently, an aging procedure was set to enhance the interaction between the surfactant template and the solution. After adjusting the pores by etching with ammonia aqueous solution, the mesoporous structure was further stabilized. Subsequently, it was sintered together with graphene to prepare a composite material of the two.

[0029] Further, in step S21, the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is (1-3) g : (5-15) g : (1.2-1.3) g : (100-300) mL.

[0030] Further, in step S3, by mass percentage, the usage amount of the porous zinc oxide-carbon conductive filler is 5-20%.

[0031] In summary, the present application has the following beneficial effects:

[0032] 1. In the technical solution of the present invention, a modified cellulose, monomer styrene, and acrylate material are used to prepare an adhesive precursor solution. With the modified cellulose as an emulsifier and in combination with an initiator, the copolymerization of the monomer styrene and acrylate material is promoted, and a styrene-acrylate copolymer is generated in the system, making the adhesive have strong adhesion and being suitable for bonding various materials. The template method is used to prepare porous zinc oxide, and graphene is added during the process to obtain a composite material of porous zinc oxide and carbon as the conductive filler in the conductive polymer adhesive. The high conductivity of graphene can provide an excellent conductive channel for the composite material, while the high specific capacitance of porous zinc oxide helps to improve the energy storage performance of the composite material.

[0033] 2. In the technical solution of the present invention, carboxymethyl cellulose is modified with hydrochloric acid dopamine, and catechol functional groups are grafted onto the carboxymethyl cellulose through an amidation reaction, while retaining the hydrophilic chain segment and hydrophobic chain segment functional groups of the carboxymethyl cellulose. It plays an emulsifying role in the process of preparing the styrene-acrylate copolymer in step S1. The obtained adhesive precursor solution can, in the subsequent preparation process, improve the dispersion effect of the filler in the adhesive system and the conductivity of the adhesive through the action of metal ion coordination bonds with zinc oxide in the conductive filler and π-π interactions with graphene. At the same time, it can also promote the stability of the conductive network through π-π interactions with the styrene-acrylate copolymer.

[0034] In addition, it can also improve the bonding effect between the adhesive and the electrode through hydrogen bond interactions with electrode materials such as Si, maintain the stability of the electrode structure, and better inhibit the volume change of the electrode material during the charge and discharge process of the battery.

[0035] 3. In the technical solution of the present invention, acrylate with 1-6 carbon atoms in the alkyl group is used to prepare the polymer. Under a unit mass, an increase in the number of carbon atoms in the alkyl group means an extension of the carbon chain and an increase in the molecular weight in the acrylate molecule. By using acrylate materials with a small atomic number of carbon atoms, the molecular weight of the polymer is reduced, and the electrical conductivity of the adhesive is improved. At the same time, an initiator and modified cellulose are used to promote cross-linking between components and promote the formation of a gel-like substance to increase the viscosity of the system. Meanwhile, conductive fillers with a non-smooth surface morphology are supplemented, which can promote topological cross-linking of the gel state around the fillers and improve the cross-linking degree of the adhesive, making up for the problem of the decreased adhesion performance of the polymer with a small molecular weight. Detailed implementation manners

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0037] The surfactant used in the specific implementation manners of this application is Pluronic F127, and the defoaming agent is BYK-022; the graphene used is monolayer graphene oxide, with an average thickness of 0.5-1.2 nm and a diameter of 4-7 μm; the brand of the carboxymethyl cellulose used is Sigma-Aldrich, and the product number is 1096611.

[0038] Example 1

[0039] A preparation method of a conductive polymer adhesive includes the following preparation steps:

[0040] S1. Mix modified cellulose, monomer styrene, and acrylate material, raise the temperature of the system to 60 °C, stir evenly at a rate of 60 rpm, then add an initiator, and stir and react at a rate of 200 rpm for 8 hours to obtain a precursor solution of the adhesive;

[0041] Among them, the initiator is azobisisobutyronitrile; the acrylate material is ethyl acrylate; the mass ratio of modified cellulose, initiator, monomer styrene, and acrylate material is 0.5:0.0001:2:5;

[0042] Among them, the modified cellulose is specifically prepared by the following steps:

[0043] S11. Add 0.5 g of 2-morpholinoethanesulfonic acid to 30 mL of deionized water, adjust the pH value of the system to 5.5 using NaOH solution, and stir the system at a rate of 30 rpm and at room temperature until dissolved to obtain a 2-morpholinoethanesulfonic acid buffer solution;

[0044] S12. Dissolve 5 g of carboxymethyl cellulose, 0.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 0.12 g of N-hydroxysuccinimide, and 0.2 g of dopamine hydrochloride in 10 mL of 2-morpholinoethanesulfonic acid buffer solution, and stir for 24 hours at room temperature under a nitrogen atmosphere to obtain modified cellulose;

[0045] S2. Prepare porous zinc oxide using the template method and add graphene during the process to obtain porous zinc oxide-carbon conductive filler. The specific operation is as follows:

[0046] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at a rate of 30 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless steel autoclave, seal it, and age it at 85°C for 24 hours to obtain an aged solution; the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is 1 g:5 g:1.2 g:100 mL;

[0047] S22. Add 0.15 g of graphene to the aged solution and stir for 3 hours at room temperature; then transfer the system to an autoclave lined with polytetrafluoroethylene, then heat it at 180°C for 6 hours, filter, add the precipitate to 10 wt% ammonia water solution according to the mass-volume ratio of 1 g:5 mL, treat it for 3 hours, then centrifuge and wash the precipitate with ethanol until the pH value of the washing solution is 7, then dry it at 50°C for 12 hours, and then heat it to 300°C at a heating rate of 2°C / minute and anneal it for 3 hours to obtain porous zinc oxide-carbon conductive filler.

[0048] S3. By mass percentage, add 5 parts of the porous zinc oxide-carbon conductive filler obtained in step S2 to 100 parts of the binder precursor solution obtained in step S1, stir evenly, add 1.5 parts of defoamer, and continue to stir the system at 1000 rpm for 5 minutes to obtain a conductive polymer binder.

[0049] Example 2

[0050] A preparation method of a conductive polymer binder, comprising the following preparation steps:

[0051] S1. Mix modified cellulose, monomer styrene, and acrylate material, raise the temperature of the system to 75°C, stir evenly at a rate of 80 rpm, add an initiator, and stir and react at a rate of 300 rpm for 10 hours to obtain a binder precursor solution;

[0052] Among them, the initiator is azobisisobutyronitrile; the acrylate material is propyl acrylate; the mass ratio of modified cellulose, initiator, monomer styrene, and acrylate material is 1.75:0.0002:3.5:5;

[0053] Among them, the modified cellulose is specifically prepared by the following steps:

[0054] S11. Add 0.65 g of 2-morpholinoethanesulfonic acid to 30 mL of deionized water, adjust the pH value of the system to 6.1 using NaOH solution, and stir the system at a rate of 60 rpm and room temperature until dissolved to obtain a 2-morpholinoethanesulfonic acid buffer solution;

[0055] S12. Dissolve 6.5 g of carboxymethyl cellulose, 0.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 0.12 g of N-hydroxysuccinimide, and 0.5 g of dopamine hydrochloride in 10 mL of 2-morpholinoethanesulfonic acid buffer solution, and stir for 24 hours at room temperature and under a nitrogen atmosphere to obtain the modified cellulose;

[0056] S2. Prepare porous zinc oxide using the template method and add graphene during the process to prepare a porous zinc oxide-carbon conductive filler. The specific operation is as follows:

[0057] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at a rate of 60 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless steel autoclave, seal it, and age it at 85 °C for 24 hours to obtain an aged solution; the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is 2 g:10 g:1.25 g:200 mL;

[0058] S22. Add 0.15 g of graphene to the aged solution and stir at room temperature for 3 hours; then transfer the system to an autoclave lined with polytetrafluoroethylene, then heat it at 180 °C for 7 hours, filter, add the precipitate to 20 wt% ammonia water according to the mass-volume ratio of 1 g:5 mL, treat it for 4.5 hours, then centrifuge and wash the precipitate with ethanol until the pH value of the washing solution is 7, then dry it at 70 °C for 18 hours, then heat it to 400 °C at a heating rate of 3 °C per minute, and anneal it for 3.5 hours to obtain the porous zinc oxide-carbon conductive filler.

[0059] S3. By mass percentage, add 12 parts of the porous zinc oxide-carbon conductive filler obtained in step S2 to 100 parts of the binder precursor solution obtained in step S1, stir evenly, add 1.8 parts of defoamer, and continue to stir the system at 1000 rpm for 8 minutes to obtain the conductive polymer binder.

[0060] Example 3

[0061] A preparation method of a conductive polymer binder, comprising the following preparation steps:

[0062] S1. Mix the modified cellulose, monomer styrene, and acrylate material, raise the system temperature to 90 °C, stir evenly at a rate of 90 rpm, add the initiator, and then stir and react at a rate of 500 rpm for 12 hours to obtain the binder precursor solution;

[0063] Among them, the initiator is benzoyl peroxide; the acrylate material is butyl acrylate; the mass ratio of the modified cellulose, initiator, monomer styrene, and acrylate material is 2:0.0003:5:5;

[0064] Among them, the modified cellulose is specifically prepared by the following steps:

[0065] S11. Add 0.8 g of 2-morpholinoethanesulfonic acid to 30 mL of deionized water, adjust the pH value of the system to 6.7 using NaOH solution, and stir the system at a rate of 90 rpm and at room temperature until dissolved to obtain the 2-morpholinoethanesulfonic acid buffer solution;

[0066] S12. Dissolve 8 g of carboxymethyl cellulose, 0.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 0.12 g of N-hydroxysuccinimide, and 0.8 g of dopamine hydrochloride in 10 mL of 2-morpholinoethanesulfonic acid buffer solution, and stir at room temperature and under a nitrogen atmosphere for 24 hours to obtain the modified cellulose;

[0067] S2. Use the template method to prepare porous zinc oxide and add graphene during the process to prepare the porous zinc oxide-carbon conductive filler. The specific operation is as follows:

[0068] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at a rate of 90 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless steel autoclave, seal it, and age it at 85 °C for 24 hours to obtain the aged solution; the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is 3 g:15 g:1.3 g:300 mL;

[0069] S22. Add 0.15 g of graphene to the aged solution and stir at room temperature for 3 hours; then transfer the system to an autoclave lined with polytetrafluoroethylene, then heat it at 180 °C for 8 hours, filter, add the precipitate to 30 wt% ammonia water according to the mass-volume ratio of 1 g:5 mL, treat it for 6 hours, then centrifuge and wash the precipitate with ethanol until the pH value of the washing solution is 7, then dry it at 80 °C for 24 hours, and then heat it to 500 °C at a heating rate of 5 °C / minute and perform annealing treatment for 4 hours to obtain the porous zinc oxide-carbon conductive filler.

[0070] S3. Add 20 parts of the porous zinc oxide-carbon conductive filler obtained in step S2 by mass percentage to 100 parts of the binder precursor solution obtained in step S1. After stirring evenly, add 2 parts of defoamer, and continue to stir the system at 1200 rpm for 10 minutes to obtain the conductive polymer binder.

[0071] Comparative Example 1

[0072] The difference between this comparative example and Example 1 is that in step S2, graphene is not added. The specific steps of this comparative example in S2 are as follows:

[0073] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at a rate of 30 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless-steel autoclave, seal it, and age it at 85°C for 24 hours to obtain an aged solution; the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is 1 g:5 g:1.2 g:100 mL;

[0074] S22. Stir the aged solution at room temperature for 3 hours; then transfer the system to an autoclave lined with polytetrafluoroethylene, then heat it at 180°C for 6 hours, filter, add the precipitate to 10 wt% ammonia water according to the mass-volume ratio of 1 g:5 mL, treat it for 3 hours, then centrifuge and wash the precipitate with ethanol until the pH value of the washing solution is 7, then dry it at 50°C for 12 hours, then heat it to 300°C at a heating rate of 2°C per minute, and perform annealing treatment for 3 hours to obtain the porous zinc oxide conductive filler.

[0075] Comparative Example 2

[0076] The difference between this comparative example and Example 1 is that in step S2, the porous zinc oxide-carbon conductive filler is obtained by blending porous zinc oxide and graphene. The specific steps of this comparative example in S2 are as follows:

[0077] S21. Add urea, zinc acetate, and surfactant to deionized water, stir at a rate of 30 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless-steel autoclave, seal it, and age it at 85°C for 24 hours to obtain an aged solution; the mass-volume ratio of urea, zinc acetate, surfactant, and deionized water is 1 g:5 g:1.2 g:100 mL;

[0078] S22. Stir the aging solution at room temperature for 3 hours; then transfer the system to an autoclave lined with polytetrafluoroethylene, and then heat it at 180 °C for 6 hours. Filter, add the precipitate to 10 wt% ammonia water solution at a mass-to-volume ratio of 1 g:5 mL, and treat for 3 hours. Then centrifuge and wash the precipitate with ethanol until the pH value of the washing solution is 7. Then dry it at 50 °C for 12 hours. Then heat it to 300 °C at a heating rate of 2 °C per minute and perform annealing treatment for 3 hours. Then blend it with 0.15 g of graphene to obtain the porous zinc oxide-carbon conductive filler.

[0079] Comparative Example 3

[0080] The difference between this comparative example and Example 1 is that in step S2, a template agent is not used to prepare porous zinc oxide; the specific steps of step S2 in this comparative example are as follows:

[0081] S21. Add urea and zinc acetate to deionized water, stir at a rate of 30 rpm at room temperature for 3 hours, transfer the obtained solution to a stainless steel autoclave, seal it and age it at 85 °C for 24 hours to obtain an aging solution; the mass-to-volume ratio of urea, zinc acetate and deionized water is 1 g:5 g:100 mL;

[0082] S22. Add 0.15 g of graphene to the aging solution and stir at room temperature for 3 hours; then transfer the system to an autoclave lined with polytetrafluoroethylene, and then heat it at 180 °C for 6 hours. Filter, wash the precipitate with ethanol until the pH value of the washing solution is 7. Then dry it at 50 °C for 12 hours. Then heat it to 300 °C at a heating rate of 2 °C per minute and perform annealing treatment for 3 hours to obtain the porous zinc oxide-carbon conductive filler.

[0083] Comparative Example 4

[0084] The difference between this comparative example and Example 1 is that in step S1, carboxymethyl cellulose is used instead of modified cellulose.

[0085] Comparative Example 5

[0086] The difference between this comparative example and Example 1 is that in step S1, the acrylate material used is octyl acrylate.

[0087] Performance Test

[0088] Now, perform performance tests on the conductive polymer adhesive samples prepared in Examples 1-3 and Comparative Examples 1-5 of this application.

[0089] The electrode sheet is prepared by the following steps:

[0090] Mix the negative electrode active material Si / C, the conductive additive SuperP, and the conductive polymer binder sample in a mass ratio of 8:1:1, and then coat it on the current collector aluminum foil and vacuum dry it at 120°C.

[0091] Conductive performance: Refer to the method described in the national standard GB / T35494.1-2017 to test the volume resistivity of the samples in different groups. Each sample is tested 5 times, and the average value is recorded.

[0092] Bonding effect test: Refer to the method described in GB / T 2790-1995 to test the bonding strength of the samples in different groups. Set the peeling angle to 180°, the peeling rate to 100 mm / minute, and the peeling width to 50 mm.

[0093] Electrochemical performance test:

[0094] Use the sample electrode sheet to build a three-electrode system. The sample electrode sheet is the working electrode, the Pt electrode is set as the auxiliary electrode, and the saturated electrode is set as the saturated calomel electrode. Determine by cyclic voltammetry, the potential range is 0.01 - 1.5V, the current density is 0.8A / g, and measure the capacitance of the sample and the retention ability after 200 cycles.

[0095] The specific performance test results are shown in Table 1 below:

[0096] Table 1

[0097]

[0098] It can be seen from the results shown in Table 1 above that: The comprehensive performance of the conductive polymer adhesives prepared in Examples 1 - 3 of this application is significantly better than that of the adhesive samples prepared in Comparative Examples 1 - 5. That is, within the limited technical solutions of this application, the prepared conductive polymer adhesives can alleviate the volume change of the electrode material during the charge and discharge process of the battery, maintain the stability of the electrode structure, thereby extending the cycle life of the battery and maintaining a high capacitance.

[0099] It can be seen from the results of Comparative Examples 1 - 3 that by combining graphene materials on porous oxidants, the structure of the conductive filler can be regulated through pore-forming agents and graphene, forming a sensitive conductive network in the adhesive, helping to disperse the current over a larger range, further improving the conductive performance of the adhesive, and at the same time retaining the advantages of high specific capacitance of porous zinc oxide.

[0100] It can be seen from the results of Comparative Example 4 that after modifying the carboxymethyl cellulose material with dopamine hydrochloride, it can promote the uniform distribution of the active material in the electrode and form good contact with the conductive agent, thereby improving the utilization rate of the active material and further increasing the capacitance of the battery.

[0101] As can be seen from the results in Comparative Example 5, by selecting materials to control the molecular weight of the polymer and the system viscosity in the binder, the bonding effect and the retention effect can be improved while maintaining a good conductive effect.

[0102] In the description of the specification, the descriptions referring to terms such as "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0103] The above content is only an example and explanation of the present invention. Those skilled in the art of the present technology can make various modifications or supplements to the described specific embodiments or use similar ways to replace them. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should fall within the protection scope of the present invention.

Claims

1. A method for preparing a conductive polymer adhesive, characterized in that: The method comprises the following preparation steps: S1, mixing modified cellulose, monomer styrene and acrylate materials, raising the system temperature to 60-90° C. and stirring, adding an initiator, and continuing to stir and react for 8-12 hours to obtain an adhesive precursor solution; Wherein, the initiator is at least one of azobisisobutyronitrile and dibenzoyl peroxide; S2. preparing porous zinc oxide by using a template method, and adding graphene in the process to prepare a porous zinc oxide-carbon conductive filler; S3, adding the porous zinc oxide-carbon conductive filler obtained in step S2 to the adhesive precursor solution obtained in step S1, stirring evenly, adding a defoamer, and continuing to stir the system at 1000-1200 rpm for 5-10 minutes to obtain a conductive polymer adhesive; Wherein, the modified cellulose in step S1 is obtained by modifying cellulose with dopamine hydrochloride.

2. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S1, the modified cellulose is specifically prepared by the following steps: S11, adding 2-morpholineethanesulfonic acid to deionized water, adjusting the pH value of the system to 5.5-6.7, and stirring the system at a rate of 30-90 rpm and room temperature until dissolved to obtain a 2-morpholineethanesulfonic acid buffer; S12, dissolving carboxymethyl cellulose, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, N-hydroxysuccinimide and dopamine hydrochloride in 2-morpholineethanesulfonic acid buffer, and stirring at room temperature under an inert gas atmosphere for 24 hours to obtain modified cellulose.

3. The method for preparing a conductive polymer adhesive according to claim 2, characterized in that: In step S12, the mass ratio of carboxymethyl cellulose to dopamine hydrochloride is (5-8):(0.2-0.8).

4. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S1, the mass ratio of modified cellulose, initiator, monomer styrene and acrylic ester material is (0.5-2):(0.0001-0.0003):(2-5):

5.

5. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S1, the acrylate material is an acrylate having an alkyl group with 1 to 6 carbon atoms.

6. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S1, the acrylate material is at least one of methyl methacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate or 2-ethylhexyl acrylate.

7. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S2, the porous zinc oxide-carbon conductive filler is specifically prepared by the following steps: S21, adding urea, zinc acetate and a surfactant into deionized water, stirring at room temperature, then sealing and aging at 80-90° C. to obtain an aging solution; S22, adding graphene to the aging liquid and stirring at room temperature; then heating the system at 170-190°C for 6-8 hours, filtering, adding the precipitate to a 10-30wt% ammonia solution, treating for 3-6 hours, then washing the precipitate and drying it at 50-80°C for 12-24 hours, then heating it to 300-500°C at a heating rate of 2-5°C / min, and annealing for 3-4 hours to obtain a porous zinc oxide-carbon conductive filler.

8. The method for preparing a conductive polymer adhesive according to claim 7, characterized in that: In step S21, the mass volume ratio of urea, zinc acetate, surfactant and deionized water is (1-3) g: (5-15) g: (1.2-1.3) g: (100-300) mL.

9. The method for preparing a conductive polymer adhesive according to claim 1, characterized in that: In step S3, the amount of the porous zinc oxide-carbon conductive filler in the conductive polymer binder is 5-20% by mass.

10. Use of the preparation method of the conductive polymer adhesive according to any one of claims 1 to 9 in lithium ion batteries.

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