WO2024016331A1 - 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置 - Google Patents

改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置 Download PDF

Info

Publication number
WO2024016331A1
WO2024016331A1 PCT/CN2022/107446 CN2022107446W WO2024016331A1 WO 2024016331 A1 WO2024016331 A1 WO 2024016331A1 CN 2022107446 W CN2022107446 W CN 2022107446W WO 2024016331 A1 WO2024016331 A1 WO 2024016331A1
Authority
WO
WIPO (PCT)
Prior art keywords
monomer
monomers
acrylamide
acrylonitrile
binder
Prior art date
Application number
PCT/CN2022/107446
Other languages
English (en)
French (fr)
Inventor
张文梦
刘会会
王兴辉
陈淑华
Original Assignee
宁德时代新能源科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 宁德时代新能源科技股份有限公司 filed Critical 宁德时代新能源科技股份有限公司
Priority to PCT/CN2022/107446 priority Critical patent/WO2024016331A1/zh
Priority to CN202280067750.3A priority patent/CN118056292A/zh
Priority to EP22930177.5A priority patent/EP4336599A1/en
Priority to US18/479,949 priority patent/US20240030451A1/en
Publication of WO2024016331A1 publication Critical patent/WO2024016331A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • This application belongs to the technical field of secondary batteries, and specifically relates to a modified binder, binder composition, preparation method, negative electrode slurry, negative electrode sheet, secondary battery, battery module, battery pack and electrical device.
  • Secondary batteries are widely used in various consumer electronics and electric vehicles due to their outstanding characteristics such as light weight, no pollution, and no memory effect. With the continuous development of the new energy industry, customers have put forward higher demand for secondary batteries.
  • Silicon-based negative electrode materials are widely used because of their high capacity. However, silicon-based negative electrode materials have poor conductivity. In order to improve the conductivity of silicon negative electrodes, carbon nanotubes are usually used as conductive agents. However, during the preparation process of silicon negative electrodes, negative electrode slurry is prone to appear. processing problems such as material gel.
  • this application provides a modified binder, binder composition, preparation method, negative electrode slurry, negative electrode sheet, secondary battery, battery module, battery pack and electrical device , aiming to prevent problems such as negative electrode slurry gel during the preparation process of negative electrode sheets and improve processing performance.
  • the first aspect of the present application provides a modified binder, including:
  • a first grafting agent is located on the conductive carbon nanotube, and the first grafting agent includes a copolymer of an acrylic monomer unit-acrylamide monomer unit and/or an acrylic monomer unit-acrylonitrile. Monomer-like units - copolymers of acrylamide-like monomer units.
  • this application at least includes the following beneficial effects:
  • the modified adhesive of the present application is provided by arranging a first grafting agent on the conductive carbon nanotube, and the first grafting agent includes a copolymer of acrylic monomer units-acrylamide monomer units and/or acrylic acid A copolymer of monomer-like units - acrylonitrile monomer units - acrylamide monomer units.
  • the first grafting agent can increase the steric hindrance of conductive carbon nanotubes, making the conductive carbon nanotubes better dispersed and reducing
  • the aggregation of conductive carbon nanotubes and the modified binder have good stability and good conductivity and can be used as conductive agents. In this way, the above-mentioned modified binder is applied to the negative electrode slurry, which can effectively prevent the negative electrode slurry from gelling and improve the processing performance.
  • the monomer corresponding to the acrylic monomer unit includes acrylic acid and a C 1 to C 6 alkyl-substituted acrylic monomer; optionally, the monomer corresponding to the acrylic monomer unit
  • the body includes acrylic acid and C 1 to C 3 alkyl-substituted acrylic monomer; further optionally, the monomer corresponding to the acrylic monomer unit includes acrylic acid, methacrylic acid, ethylacrylic acid and propylacrylic acid. one or more;
  • the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile, C 1 to C 6 alkyl-substituted acrylonitrile monomer; optionally, the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile , C 1 to C 3 alkyl-substituted acrylonitrile monomers; further optionally, the monomers corresponding to the acrylonitrile monomer units include acrylonitrile, methacrylonitrile, ethacrylonitrile and propylene One or more types of nitriles;
  • the monomers corresponding to the acrylamide monomer units include acrylamide and C 1 to C 6 alkyl-substituted acrylamide monomers; optionally, the monomers corresponding to the acrylamide monomer units include acrylamide , C 1 to C 3 alkyl-substituted acrylamide monomers; further optionally, the monomers corresponding to the acrylamide monomer units include acrylamide, N, N-dimethylacrylamide, ethyl propylene One or more of amide and propylacrylamide.
  • the viscosity of the aqueous solution of the modified binder with a solid content of 0.8% to 1.4% is 20,000 mPa ⁇ s to 40,000 mPa ⁇ s.
  • the weight average molecular weight of the first grafting agent is 5,000 Da to 100,000 Da.
  • the conductive carbon nanotubes include single-walled carbon nanotubes and multi-walled carbon nanotubes.
  • the length of the conductive carbon nanotubes is 1 ⁇ m ⁇ 5 ⁇ m.
  • the second aspect of the present application provides a binder composition, including the modified binder of the first aspect of the present application; at 25°C, the viscosity of the second binder with a solid content of 3% is 2000 mPa. ⁇ s ⁇ 7000mPa ⁇ s
  • the second binder includes a copolymer of acrylic monomer units-acrylamide monomer units and/or acrylic monomer units-acrylonitrile monomer units-acrylamide Copolymer of monomer units.
  • the monomer corresponding to the acrylic monomer unit includes acrylic acid and a C 1 to C 6 alkyl-substituted acrylic monomer; optionally, the monomer corresponding to the acrylic monomer unit
  • the body includes acrylic acid and C 1 to C 3 alkyl-substituted acrylic monomer; further optionally, the monomer corresponding to the acrylic monomer unit includes acrylic acid, methacrylic acid, ethylacrylic acid and propylacrylic acid. one or more;
  • the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile, C 1 to C 6 alkyl-substituted acrylonitrile monomer;
  • the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile , C 1 to C 3 alkyl-substituted acrylonitrile monomers;
  • the monomers corresponding to the acrylonitrile monomer units include acrylonitrile, methacrylonitrile, ethacrylonitrile and propylene One or more types of nitriles;
  • the monomers corresponding to the acrylamide monomer units include acrylamide and C 1 to C 6 alkyl-substituted acrylamide monomers; optionally, the monomers corresponding to the acrylamide monomer units include acrylamide , C 1 to C 3 alkyl-substituted acrylamide monomers; further optionally, the monomers corresponding to the acrylamide monomer units include acrylamide, N, N-dimethylacrylamide, ethyl propylene One or more of amide and propylacrylamide.
  • the second binder has a polar group
  • the polar group includes one or more of -COOH, CN and amide group.
  • the weight average molecular weight of the second binder is 50,000 Da to 2,000,000 Da.
  • the mass ratio of the modified binder and the second binder is 1:(8-12).
  • the viscosity of the aqueous solution of the adhesive composition with a solid content of 3% is 15,000 mPa ⁇ s to 30,000 mPa ⁇ s.
  • the third aspect of this application provides a preparation method of modified binder, including the following steps:
  • Acrylic monomers, acrylamide monomers and the conductive carbon nanotubes react in a polyvinyl alcohol cellulose dispersion containing persulfate to form the modified binder;
  • the raw materials for preparing the modified binder also include acrylonitrile monomers.
  • the mass ratio of the acrylic monomer, the acrylonitrile monomer, the acrylamide monomer and the conductive carbon nanotube is (0.2 ⁇ 0.8): (0 ⁇ 0.18):(0.06 ⁇ 0.18):(0.2 ⁇ 0.6).
  • the fourth aspect of the present application provides a preparation method of an adhesive composition, including the following steps:
  • the raw materials for preparation in step S2 also include acrylamide monomers.
  • step S2 the mass proportion of acrylic monomers in the total monomers is 50% to 80%, and the mass proportion of acrylonitrile monomers in the total monomers is 20% to 20%. 40%, and the mass proportion of acrylamide monomers in the total monomers is 0% to 20%.
  • the fifth aspect of the present application provides a negative electrode slurry, including the modified binder of the first aspect of the present application, the binder composition of the second aspect of the present application, and the modified binder prepared by the method of the third aspect of the present application. At least one of a binder or a binder composition prepared according to the method of the fourth aspect of the present application.
  • the sixth aspect of this application provides a negative electrode sheet, including:
  • a negative active material layer is located on at least one surface of the negative current collector
  • the negative active material layer includes the modified binder of the first aspect of the present application, the binder composition of the second aspect of the present application, the modified binder prepared by the method of the third aspect of the present application, or the modified binder prepared according to the method of the third aspect of the present application. At least one of the adhesive compositions prepared by the method of the fourth aspect of the application.
  • the negative active material layer further includes a first negative active material and a second negative active material, and the first negative active material, the second negative active material and the binder are combined
  • the mass ratio of objects is (80 ⁇ 95):(1 ⁇ 20):(0.5 ⁇ 2).
  • a seventh aspect of the present application provides a secondary battery, which includes the negative electrode plate of the sixth aspect of the present application.
  • An eighth aspect of the present application provides a battery module, which includes the secondary battery of the seventh aspect of the present application.
  • a ninth aspect of the present application provides a battery pack, which includes the battery module of the eighth aspect of the present application.
  • a tenth aspect of the present application provides an electrical device, which includes at least one of the secondary battery of the seventh aspect of the present application, the battery module of the eighth aspect of the present application, or the battery pack of the ninth aspect of the present application.
  • Figure 1 is a scanning electron microscope (SEM) picture of the adhesive composition in Example 1.
  • Figure 2 is a scanning electron microscope (SEM) picture of an individual single-walled carbon nanotube.
  • Figure 3 is a resistivity comparison chart of the binder composition and single-walled carbon nanotubes in Example 1.
  • Figure 4 is a schematic diagram of the cycle capacity retention results of the secondary batteries in Example 12 and Comparative Example 1;
  • FIG. 5 is a schematic diagram of an embodiment of a secondary battery.
  • FIG. 6 is an exploded view of FIG. 5 .
  • Figure 7 is a schematic diagram of an embodiment of a battery module.
  • Figure 8 is a schematic diagram of an embodiment of a battery pack.
  • FIG. 9 is an exploded view of FIG. 8 .
  • FIG. 10 is a schematic diagram of an embodiment of a device in which a secondary battery is used as a power source.
  • Ranges as disclosed herein are defined in terms of lower and upper limits. A given range is defined by selecting a lower limit and an upper limit that define the boundaries of the particular range. Ranges defined in this manner may be inclusive or exclusive of the endpoints, and may be arbitrarily combined, that is, any lower limit may be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, understand that ranges of 60-110 and 80-120 are also expected. Furthermore, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2- 3, 2-4 and 2-5.
  • the numerical range “a-b” represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers.
  • the numerical range “0-5" means that all real numbers between "0-5" have been listed in this article, and "0-5" is just an abbreviation of these numerical combinations.
  • a certain parameter is an integer ⁇ 2
  • the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially.
  • step (c) means that step (c) may be added to the method in any order.
  • the method may include steps (a), (b) and (c). , may also include steps (a), (c) and (b), may also include steps (c), (a) and (b), etc.
  • first and second are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as “first” and “second” may explicitly or implicitly include at least one of these features.
  • a plurality means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.
  • everal means at least one, such as one, two, etc., unless otherwise expressly and specifically limited.
  • Silicon-based negative electrode materials are widely used because of their high capacity. However, silicon-based negative electrode materials have poor conductivity. In order to improve the conductivity of silicon negative electrodes, carbon nanotubes are usually used as conductive agents. However, during the preparation process of silicon negative electrodes, negative electrode slurry is prone to appear. processing problems such as material gel. The technicians of this application found that this is mainly because carbon nanotubes are difficult to disperse and easily aggregate, resulting in gel formation in the negative electrode slurry. In addition, the volume of silicon-based negative electrode materials expands and the particles pulverize during the cycle, resulting in reduced cycle life and poor cycle performance.
  • modified binders include:
  • the first grafting agent is located on the conductive carbon nanotube.
  • the first grafting agent includes a copolymer of acrylic monomer units-acrylamide monomer units and/or acrylic monomer units-acrylonitrile monomer units. -Copolymer of acrylamide monomer units.
  • the modified adhesive of the present application disposes a first grafting agent on the conductive carbon nanotubes, and the first grafting agent includes acrylic monomer units-acrylamide monomer units. Copolymer and/or copolymer of acrylic monomer unit-acrylonitrile monomer unit-acrylamide monomer unit, the first grafting agent can increase the steric hindrance of the conductive carbon nanotube, making the conductive carbon nanotube It can obtain better dispersion and reduce the aggregation of conductive carbon nanotubes.
  • the modified binder has good stability and good conductivity and can be used as a conductive agent. In this way, the above-mentioned modified binder is applied to the negative electrode slurry, which can effectively prevent the negative electrode slurry from gelling and improve the processing performance.
  • the first grafting agent may only include a copolymer of acrylic monomer units-acrylamide monomer units, or may only include acrylic monomer units-acrylonitrile monomer units-acrylamide monomers.
  • the copolymer of units may also include a copolymer of acrylic monomer units-acrylamide monomer units and a copolymer of acrylic monomer units-acrylonitrile monomer units-acrylamide monomer units.
  • the first grafting agent is grafted onto the conductive carbon nanotubes through an addition polymerization reaction.
  • the inventor found that when the negative electrode active material of the present application meets the above design conditions, if it also optionally meets one or more of the following conditions, the processing performance of the negative electrode slurry can be further improved. and cycle performance of secondary batteries.
  • the monomers corresponding to the acrylic monomer units include acrylic acid, C 1 to C 6 alkyl-substituted acrylic monomers; optionally, the monomers corresponding to the acrylic monomer units include acrylic acid, C 1 to C 3 alkyl-substituted acrylic monomer; further optionally, the monomer corresponding to the acrylic monomer unit includes one or more of acrylic acid, methacrylic acid, ethylacrylic acid and propylacrylic acid.
  • the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile, C 1 to C 6 alkyl-substituted acrylonitrile monomer; optionally, the monomer corresponding to the acrylonitrile monomer unit The unit includes acrylonitrile and C 1 to C 3 alkyl-substituted acrylonitrile monomers; further optionally, the monomers corresponding to the acrylonitrile unit include acrylonitrile, methacrylonitrile, ethacrylonitrile and propylene One or more acrylonitriles.
  • the monomers corresponding to the acrylamide monomer units include acrylamide and C 1 to C 6 alkyl-substituted acrylamide monomers; optionally, the monomers corresponding to the acrylamide monomer units include The monomers include acrylamide and C 1 to C 3 alkyl-substituted acrylamide monomers; further optionally, the monomers corresponding to the acrylamide monomer units include acrylamide, N, N-dimethylacrylamide, ethylene One or more of acrylamide and propylacrylamide.
  • the viscosity of an aqueous solution of a modified binder with a solid content of 0.8% to 1.4% is 20000mPa ⁇ s ⁇ 40000mPa ⁇ s; for example, it can be 25000mPa ⁇ s ⁇ 40000mPa ⁇ s, 30000mPa ⁇ s ⁇ 40000mPa ⁇ s, 35000mPa ⁇ s ⁇ 40000mPa ⁇ s or 25000mPa ⁇ s ⁇ 35000mPa ⁇ s, etc.; further, at 25°C, the viscosity of the aqueous solution of the modified binder with a solid content of 1% It is 24000mPa ⁇ s ⁇ 37000mPa ⁇ s.
  • the viscosity of the aqueous solution of the modified binder mentioned above was tested using the following method: weigh 500g of the aqueous solution of the modified binder to be tested with a solid content of 0.8 to 1.4%, stir and dissolve for 2 hours to make the modified binder to be tested viscous. Measure the adhesive after it is completely stable and uniform. Different rotors correspond to different viscosities. Detection temperature: 25 ⁇ 1°C; Used rotor and speed: 64# rotor, 12r/min, take the 6th minute value; Equipment model: DV-2TLV Brookfield viscometer.
  • the weight average molecular weight of the first grafting agent is 5,000 Da to 100,000 Da; for example, it can be 6,000 Da to 100,000 Da, 7,000 Da to 90,000 Da, 10,000 Da to 80,000 Da, or 30,000 Da to 70,000 Da, etc.
  • the conductive carbon nanotubes include single-walled carbon nanotubes and multi-walled carbon nanotubes.
  • Conductive carbon nanotubes have the most efficient conductivity, and their conductivity is much higher than that of conductive carbon black. They can build an efficient conductive network in the silicon negative electrode sheet; when a modified binder containing conductive carbon nanotubes is used in the silicon negative electrode, On the one hand, it can effectively reduce the resistance of the silicon anode, reduce polarization, improve electron transmission capabilities, reduce the amount of conductive carbon black, and thereby increase the amount of negative active material; on the other hand, modified binders containing conductive carbon nanotubes Coated on the surface of the negative active material, it can inhibit the expansion of silicon materials, reduce particle powdering, extend cycle life, and improve cycle performance.
  • the length of the conductive carbon nanotube is 1 ⁇ m to 5 ⁇ m; for example, it may be 2 ⁇ m to 5 ⁇ m, 3 ⁇ m to 5 ⁇ m, or 4 ⁇ m to 5 ⁇ m. Further optionally, the length of the conductive carbon nanotubes is 3 ⁇ m to 5 ⁇ m.
  • the embodiment of the present application also provides a preparation method of modified binder, including the following steps:
  • Acrylic monomers, acrylamide monomers and conductive carbon nanotubes react in a polyvinyl alcohol cellulose dispersion containing persulfate to form a modified binder;
  • the raw materials for preparing the modified binder also include acrylonitrile monomers.
  • the mass ratio of persulfate and conductive carbon nanotubes is (0.03 ⁇ 0.09): (2 ⁇ 6); the mass ratio of polyvinyl alcohol cellulose dispersion and conductive carbon nanotubes is (2 ⁇ 6): (0.2 ⁇ 0.6); further, the concentration of the polyvinyl alcohol cellulose dispersion is 1%.
  • the reaction temperature is 70°C to 80°C; for example, it can be 72°C to 80°C, 75°C to 80°C, or 73°C to 78°C, etc.
  • the reaction time is 6h to 12h; for example, it can be 8h to 12h, 10h to 12h or 7 to 11h, etc.
  • the mass ratio of acrylic monomers, acrylonitrile monomers, acrylamide monomers and conductive carbon nanotubes is (0.2 ⁇ 0.8):(0 ⁇ 0.18):(0.06 ⁇ 0.18) :(0.2 ⁇ 0.6); for example, it can be (0.4 ⁇ 0.8):(0.2 ⁇ 0.18):(0.10 ⁇ 0.18):(0.4 ⁇ 0.6) or (0.3 ⁇ 0.7):(0 ⁇ 0.15):(0.08 ⁇ 0.16):(0.2 ⁇ 0.5) etc.
  • the embodiment of the present application also provides a binder composition, including the above-mentioned modified binder and a second binder; at 25°C, the viscosity of the second binder with a solid content of 3% is 2000 mPa. ⁇ s ⁇ 7000mPa ⁇ s; for example, it can be 2000mPa ⁇ s ⁇ 7000mPa ⁇ s, 3000mPa ⁇ s ⁇ 7000mPa ⁇ s, 4000mPa ⁇ s ⁇ 7000mPa ⁇ s or 5000mPa ⁇ s ⁇ 6000mPa ⁇ s, etc.
  • the second binder can suspend and further disperse the conductive carbon nanotubes in the modified binder, thereby improving the stability of the binder composition. sex.
  • the viscosity of the second binder with a solid content of 3% is 5000 mPa ⁇ s to 6500 mPa ⁇ s.
  • the viscosity of the second binder mentioned above is tested using the following method: weigh 15.0g of the second binder to be tested in dry weight, add pure water until the total weight of the second binder to be tested and pure water is 500g, stir and dissolve for 2 hours so that the second binder to be measured is completely dispersed and evenly dispersed, and then measured.
  • Different rotors correspond to different viscosities. Detection temperature: 25 ⁇ 1°C; Used rotor and speed: 64# rotor, 12r/min, take the 6th minute value; Equipment model: DV-2TLV Brookfield viscometer.
  • the second binder includes a copolymer of acrylic monomer units-acrylamide monomer units and/or acrylic monomer units-acrylonitrile monomer units-acrylamide monomers. copolymer of units.
  • the second binder may only include a copolymer of acrylic monomer units-acrylamide monomer units, or may only include acrylic monomer units-acrylonitrile monomer units-acrylamide monomers.
  • the copolymer of units may also include a copolymer of acrylic monomer units-acrylamide monomer units and a copolymer of acrylic monomer units-acrylonitrile monomer units-acrylamide monomer units.
  • the monomers corresponding to the acrylic monomer units include acrylic acid, C 1 to C 6 alkyl-substituted acrylic monomers; optionally, the monomers corresponding to the acrylic monomer units include acrylic acid, C 1 to C 3 alkyl-substituted acrylic monomer; further optionally, the monomer corresponding to the acrylic monomer unit includes one or more of acrylic acid, methacrylic acid, ethylacrylic acid and propylacrylic acid.
  • the monomer corresponding to the acrylonitrile monomer unit includes acrylonitrile, C 1 to C 6 alkyl-substituted acrylonitrile monomer; optionally, the monomer corresponding to the acrylonitrile monomer unit The unit includes acrylonitrile, C 1 to C 3 alkyl-substituted acrylonitrile monomer; further optionally, the corresponding monomers of the acrylonitrile unit include acrylonitrile, methacrylonitrile, ethacrylonitrile and propylene One or more acrylonitriles.
  • the monomers corresponding to the acrylamide monomer units include acrylamide, C 1 to C 6 alkyl-substituted acrylamide monomers; optionally, the monomers corresponding to the acrylamide monomer units The monomers include acrylamide and C 1 to C 3 alkyl-substituted acrylamide monomers; further optionally, the monomers corresponding to the acrylamide monomer units include acrylamide, N, N-dimethylacrylamide, ethylene One or more of acrylamide and propylacrylamide.
  • the second binder has a polar group; when the second binder or the binder composition containing the second binder is used for the silicon negative electrode, on the one hand, the polarity The group can form hydrogen bonds with the surface of the current collector, so that the second binder or binder composition has good binding properties; on the other hand, the second binder or binder composition is soluble in water, It is a water-soluble binder that is used in silicon negative electrodes and can be easily coated on the surface of negative active material particles. It can further inhibit the expansion of silicon materials, reduce particle powdering, extend cycle life, and improve cycle performance.
  • the polar group includes one or more of -COOH, -CN and amide group. Further optionally, the polar group includes one or both -COOH and -CN.
  • the weight average molecular weight of the second binder is 50,000 Da to 2,000,000 Da; for example, it can be 1,00,000 Da to 2,000,000 Da, 5,000,000 Da to 2,000,000 Da, 100,000 Da to 2,000,000 Da, or 1,500,000 Da to 2,000,000 Da, etc.
  • the mass ratio of the modified binder and the second binder is 1:(8-12); for example, it can be 1:(9-12), 1:(10-12) , 1:(9.5 ⁇ 11.5) or 1:(8 ⁇ 11), etc.
  • the viscosity of an aqueous solution of a binder composition with a solid content of 3% is 15,000 mPa ⁇ s to 30,000 mPa ⁇ s; for example, it can be 17,000 mPa ⁇ s to 30,000 mPa ⁇ s, 20,000 mPa ⁇ s ⁇ 30000mPa ⁇ s, 25000mPa ⁇ s ⁇ 30000mPa ⁇ s or 15000mPa ⁇ s ⁇ 25000mPa ⁇ s, etc.
  • the binder composition with high viscosity is used in the silicon negative electrode, it can have a better suspension effect on the negative electrode active material.
  • the viscosity of the above-mentioned binder composition is tested using the following method: weigh 500g of the aqueous solution of the binder composition to be tested with a solid content of 3%, stir and dissolve for 2 hours to make the binder composition to be tested completely stable and uniform. After measurement, different rotors correspond to different viscosities. Detection temperature: 25 ⁇ 1°C; Used rotor and speed: 64# rotor, 12r/min, take the 6th minute value; Equipment model: DV-2TLV Brookfield viscometer.
  • the embodiment of the present application also provides a preparation method of the adhesive composition, including the following steps:
  • the raw materials for preparation in step S2 also include acrylamide monomers.
  • step S2 the mass proportion of acrylic monomers in the total monomers is 50% to 80%, and the mass proportion of acrylonitrile monomers in the total monomers is 20% to 20%. 40%, and the mass proportion of acrylamide monomers in the total monomers is 0% to 20%.
  • the embodiment of the present application also provides a negative electrode slurry, which is prepared by the above-mentioned modified binder, the above-mentioned binder composition, the above-mentioned binder composition, and the above-mentioned modified binder preparation method. At least one of the modified binder or the binder composition prepared by the above-mentioned binder composition preparation method.
  • the embodiment of the present application also provides a preparation method of negative electrode slurry, including the following steps:
  • plasticizer Add plasticizer, binder composition, styrene-butadiene rubber and the second part of deionized water to the first mixed liquid, stir and mix to prepare negative electrode slurry.
  • the embodiment of the present application also provides a negative electrode sheet, including:
  • a negative active material layer located on at least one surface of the negative current collector
  • the negative active material layer includes the above-mentioned modified binder, the above-mentioned binder composition, the above-mentioned binder composition, the modified binder prepared by the above-mentioned modified binder preparation method, or the above-mentioned binder. At least one of the adhesive compositions prepared by a method for preparing the adhesive composition.
  • the negative active material layer further includes a first negative active material and a second negative active material, and the mass ratio of the first negative active material, the second negative active material and the binder composition is (80 ⁇ 95):(1 ⁇ 20):(0.5 ⁇ 2); for example, it can be (85 ⁇ 95):(4 ⁇ 20):(0.5 ⁇ 1), (90 ⁇ 95):(1 ⁇ 5):( 1 ⁇ 1.5) or (80 ⁇ 90):(3 ⁇ 17):(0.7 ⁇ 1.7) etc.
  • the first negative active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, tin-based materials, lithium titanate, etc.; the tin-based material may be selected from elemental tin, tin oxide compound and tin alloy.
  • the present application is not limited to these materials, and other traditional materials that can be used as battery negative electrode active materials can also be used. Only one type of these negative electrode active materials may be used alone, or two or more types may be used in combination.
  • the second negative active material may be selected from at least one of elemental silicon, silicon oxygen compounds, silicon carbon composites, silicon nitrogen composites, and silicon alloys. Only one type of these negative electrode active materials may be used alone, or two or more types may be used in combination.
  • the mass ratio of the first negative electrode active material, the second negative electrode active material and the binder composition mentioned above can be measured by the following method: separately measure the first negative electrode active material, the second negative electrode active material and the binder composition in the negative electrode active material layer. mass of the adhesive composition, and then calculate the ratio of the three.
  • the negative active material layer optionally further includes a conventional binder.
  • the conventional binder can be selected from sodium carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol ( At least one of PVA), sodium alginate (SA), polymethacrylic acid (PMAA) and carboxymethyl chitosan (CMCS).
  • the negative active material layer usually also includes conductive agents and other optional auxiliaries.
  • the conductive agent may be one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • PTC thermistor materials may be PTC thermistor materials, etc.
  • the negative electrode current collector can use conventional metal foil or composite current collector.
  • the metal foil may be copper foil.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base material.
  • the composite current collector can be formed by forming metal materials (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the negative electrode sheet can be prepared by dispersing the above-mentioned components for preparing the negative electrode sheet, such as negative active material, conductive agent, binder and any other components in a solvent (such as deionized water) , to form a negative electrode slurry; the negative electrode slurry is coated on the negative electrode current collector, and after drying, cold pressing and other processes, the negative electrode piece can be obtained.
  • a solvent such as deionized water
  • Secondary batteries refer to batteries that can be recharged to activate active materials and continue to be used after the battery is discharged.
  • a secondary battery typically includes a positive electrode sheet, the negative electrode sheet provided above in this application, a separator and an electrolyte.
  • active ions are inserted and detached back and forth between the positive and negative electrodes.
  • the isolation film is arranged between the positive electrode piece and the negative electrode piece to play the role of isolation.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • a positive electrode sheet usually includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector.
  • the positive electrode film layer includes a positive electrode active material.
  • the positive electrode current collector has two surfaces opposite in its own thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.
  • the positive electrode current collector may use a metal foil or a composite current collector.
  • the metal foil aluminum foil can be used.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer.
  • the composite current collector can be formed by forming metal materials (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver and silver alloys, etc.) on polymer material substrates (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the cathode active material may be a cathode active material known in the art for lithium ion batteries.
  • the cathode active material may include at least one of the following materials: an olivine-structured lithium-containing phosphate, a lithium transition metal oxide, and their respective modified compounds.
  • the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials of batteries can also be used. Only one type of these positive electrode active materials may be used alone, or two or more types may be used in combination.
  • lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO 2 ), lithium nickel oxides (such as LiNiO 2 ), lithium manganese oxides (such as LiMnO 2 , LiMn 2 O 4 ), lithium Nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (can also be abbreviated to NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (can also be abbreviated to NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (can also be abbreviated to NCM 622 ), LiNi At least one of 0.8 Co 0.1 Mn 0.1 O 2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as Li Li
  • the olivine structure contains Examples of lithium phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP)), composites of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), lithium manganese phosphate and carbon. At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • lithium iron phosphate such as LiFePO 4 (also referred to as LFP)
  • composites of lithium iron phosphate and carbon such as LiMnPO 4
  • LiMnPO 4 lithium manganese phosphate and carbon.
  • At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • the cathode active material may be a cathode active material known in the art for sodium-ion batteries.
  • the cathode active material may be a cathode active material known in the art for sodium-ion batteries.
  • only one type of positive electrode active material may be used alone, or two or more types may be combined.
  • the positive active material can be selected from sodium iron composite oxide (NaFeO 2 ), sodium cobalt composite oxide (NaCoO 2 ), sodium chromium composite oxide (NaCrO 2 ), sodium manganese composite oxide (NaMnO 2 ), sodium nickel Composite oxide (NaNiO 2 ), sodium nickel titanium composite oxide (NaNi 1/2 Ti 1/2 O 2 ), sodium nickel manganese composite oxide (NaNi 1/2 Mn 1/2 O 2 ), sodium iron manganese composite Oxide (Na 2/3 Fe 1/3 Mn 2/3 O 2 ), sodium nickel cobalt manganese composite oxide (NaNi 1/3 Co 1/3 Mn 1/3 O 2 ), sodium iron phosphate compound (NaFePO 4 ), sodium manganese phosphate compound (NaMn P O 4 ), sodium cobalt phosphate compound (NaCoPO 4 ), Prussian blue materials, polyanionic materials (phosphates, fluorophosphates, pyrophosphates, sulfates), etc.,
  • the positive electrode film layer also optionally includes binders, conductive agents and other optional auxiliaries.
  • the binder may include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene At least one of ethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer and fluorine-containing acrylate resin.
  • PVDF polyvinylidene fluoride
  • PTFE polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • VDF polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • VDF polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • VDF polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the positive electrode sheet can be prepared in the following manner: the above-mentioned components for preparing the positive electrode sheet, such as the positive active material, the conductive agent, the binder and any other components are dispersed in a solvent (such as N-methyl pyrrolidone) to form a positive electrode slurry; the positive electrode slurry is coated on the positive electrode current collector, and after drying, cold pressing and other processes, the positive electrode piece can be obtained.
  • a solvent such as N-methyl pyrrolidone
  • the secondary battery further includes a separator film.
  • a separator film There is no particular restriction on the type of isolation membrane in this application. Any well-known porous structure isolation membrane with good chemical stability and mechanical stability can be used.
  • the material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the isolation film can be a single-layer film or a multi-layer composite film, with no special restrictions. When the isolation film is a multi-layer composite film, the materials of each layer can be the same or different, and there is no particular limitation.
  • the positive electrode piece, the negative electrode piece and the separator film can be made into an electrode assembly through a winding process or a lamination process.
  • the secondary battery may include an electrolyte that serves to conduct ions between a positive electrode and a negative electrode.
  • the electrolyte solution may include electrolyte salts and solvents.
  • the electrolyte salt may be selected from lithium hexafluorophosphate (LiPF 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiClO 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bisfluorosulfonyl imide ( LiFSI), lithium bistrifluoromethanesulfonimide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluoromethanesulfonate borate (LiDFOB), lithium dioxalatoborate (LiBOB), lithium difluorophosphate (LiPO 2 F 2 ), one or more of lithium difluorodioxalate phosphate (LiDFOP) and lithium tetrafluorooxalate phosphate (LiTFOP).
  • LiFSI lithium bisfluorosulfonyl imide
  • LiTFSI lithium bis
  • the solvent may be selected from ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), carbonic acid Dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), butylene carbonate (BC), fluoroethylene carbonate (FEC), methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB), One or more of ethyl butyrate (EB), 1,4-butyrolactone (GBL), sulfolane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS) and diethyl sulf
  • additives are also included in the electrolyte.
  • additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain properties of the battery, such as additives that improve the overcharge performance of the battery, additives that improve the high-temperature performance of the battery, and additives that improve the low-temperature performance of the battery. Additives etc.
  • the secondary battery of the present application is a lithium-ion secondary battery.
  • the secondary battery can be prepared according to conventional methods in the art, for example, the positive electrode sheet, the separator film, and the negative electrode sheet are wound (or stacked) in order, so that the separator film is between the positive electrode sheet and the negative electrode sheet for isolation. function to obtain the battery core, place the battery core in the outer package, inject the electrolyte and seal it to obtain a secondary battery.
  • the embodiments of the present application have no particular limitation on the shape of the secondary battery, which may be cylindrical, square, or any other shape. As shown in FIG. 5 , a square-structured secondary battery 5 is shown as an example.
  • the secondary battery may include an outer packaging.
  • the outer packaging can be used to package the above-mentioned electrode assembly and electrolyte.
  • the outer packaging of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer packaging of the secondary battery may also be a soft bag, such as a bag-type soft bag.
  • the material of the soft bag may be plastic, and examples of the plastic include polypropylene, polybutylene terephthalate, polybutylene succinate, and the like.
  • the outer package may include a housing 51 and a cover 53 .
  • the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity.
  • the housing 51 has an opening communicating with the accommodation cavity, and the cover plate 53 can cover the opening to close the accommodation cavity.
  • the positive electrode piece, the negative electrode piece and the isolation film can be formed into the electrode assembly 52 through a winding process or a lamination process.
  • the electrode assembly 52 is packaged in the containing cavity.
  • the electrolyte soaks into the electrode assembly 52 .
  • the number of electrode assemblies 52 contained in the secondary battery 5 can be one or more, and can be adjusted according to needs.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be multiple. The specific number can be adjusted according to the application and capacity of the battery module.
  • FIG. 7 shows the battery module 4 as an example.
  • a plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4 .
  • the plurality of secondary batteries 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a receiving space in which a plurality of secondary batteries 5 are received.
  • the above-mentioned battery modules can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be adjusted according to the application and capacity of the battery pack.
  • the battery pack 1 may include a battery box and a plurality of battery modules 4 arranged in the battery box.
  • the battery box includes an upper box 2 and a lower box 3 .
  • the upper box 2 can be covered with the lower box 3 and form a closed space for accommodating the battery module 4 .
  • Multiple battery modules 4 can be arranged in the battery box in any manner.
  • the present application also provides an electrical device, which includes at least one of the secondary battery, battery module, or battery pack.
  • the secondary battery, battery module or battery pack may be used as a power source for the device or as an energy storage unit for the device.
  • the device may be, but is not limited to, a mobile device (such as a mobile phone, a laptop, etc.), an electric vehicle (such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, or an electric golf ball). vehicles, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.
  • the device can select secondary batteries, battery modules or battery packs according to its usage requirements.
  • FIG. 10 shows an electrical device 6 as an example.
  • the electric device 6 is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or the like.
  • battery packs or battery modules can be used.
  • the device may be a mobile phone, a tablet, a laptop, etc.
  • the device is usually required to be thin and light, and a secondary battery can be used as a power source.
  • step 3 Mix 2kg of the pre-dispersion in step 1) with 720g of the solution in step 2), stir for 120 minutes at a speed of 1200r/min, the temperature of the stirring tank is 80°C, add LiOH solution to adjust the pH to 7, and then add The solid content of the adhesive composition was adjusted to 3% with ionized water to prepare a solution containing the adhesive composition.
  • the mass ratio of the modified binder and the second binder is 1:12.
  • the preparation method of the adhesive composition in Example 2-11 is basically the same as the preparation method of the adhesive composition in Example 1. The only difference lies in: the type of each monomer and the type of each monomer when preparing the modified adhesive. At least one of the usage ratio of the conductive carbon nanotubes, the type of monomers and the usage percentage of each monomer when preparing the second binder, and the mass ratio of the modified binder and the second binder are different. See Table 1 for details.
  • the adhesive composition and individual single-walled carbon nanotubes prepared in Example 1 were diluted to a solid content of 0.05% of the single-walled carbon nanotubes, and then were dropped on copper foil and dried with ZEISS sigma. 300 scanning electron microscope for testing, and then test according to standard JY/T010-1996, and observe the morphology of the sample.
  • the adhesive part in the adhesive composition prepared in Example 1 cannot be observed under a scanning electron microscope, and only the morphology of single-walled carbon nanotubes can be observed.
  • Example 1 The SEM results of Example 1 are shown in Figure 1, and the SEM results of individual single-walled carbon nanotubes are shown in Figure 2. It can be seen from Figure 1 and Figure 2 that the single-walled carbon nanotubes in the binder composition in Example 1 have few impurities and are evenly dispersed; while the single-walled carbon nanotubes have many impurities, and there are many impurities between the single-walled carbon nanotubes. gather. It shows that the first grafting agent can increase the steric hindrance of single-walled carbon nanotubes, and the second binder can suspend and further disperse the single-walled carbon nanotubes, so that the conductive carbon nanotubes are better dispersed. Reduce aggregation of conductive carbon nanotubes.
  • the binder composition of Example 1 and the single-walled carbon nanotubes were gradually diluted according to the solid content of the single-walled carbon nanotubes being 0.2%, 0.1%, 0.08%, 0.06%, 0.04%, and 0.02%, respectively.
  • the upper, middle and lower channels are all immersed in the glue solution. Record the data of the upper, middle and lower channels and take the average. .
  • the results are shown in Figure 3.
  • the binder composition in Example 1 has lower resistivity, better conductivity, and only requires a very small amount of binder combination. Materials can achieve the effect of building a conductive network.
  • the solution containing the modified binder, the solution containing the second binder, and the solution containing the binder composition in each example were taken for viscosity measurement. details as follows:
  • M11 represents the amount of acrylic monomer used in preparing the modified adhesive
  • M12 represents the amount of acrylonitrile monomer used in preparing the modified adhesive
  • M13 represents the amount of acrylamide monomer used in preparing the modified adhesive.
  • Dosage M10 represents the amount of conductive carbon nanotubes used when preparing the modified binder
  • eta1 represents the viscosity of a solution with a solid content of 1% of the modified binder at 25°C
  • eta2 represents the solid content of the second binder at 25°C.
  • eta3 represents the viscosity of a solution with a solid content of 3% of the binder composition at 25°C
  • W1 represents the mass ratio of the modified binder and the second binder.
  • the preparation method of the negative electrode slurry in Examples 13-34 is basically the same as the preparation method of the negative electrode slurry in Example 12. The only difference lies in: the type of binder composition used in the preparation, graphite and silicon powder, and the binder. At least one of the mass ratios between the compositions is different; at the same time, in Examples 13-34, the addition amounts of deionized water and styrene-butadiene rubber are adjusted so that the total mass of the finally prepared negative electrode slurry is the same as that in Example 12 The total mass of the middle and negative electrode slurries is the same. See Table 2 below for details.
  • the preparation method of the negative electrode slurry in Comparative Example 1 is basically the same as the preparation method of the negative electrode slurry in Example 12. The only difference is that no binder composition is added, and polyacrylic acid binder and single-walled carbon nanotubes are used instead. , the sum of the masses of the aqueous binder and the single-walled carbon nanotubes is the same as the mass of the binder composition, and the mass of the single-walled carbon nanotubes is the same as the mass of the single-walled carbon nanotubes contained in the binder composition.
  • Comparative Example 1 At the same time, in Comparative Example 1, the addition amounts of deionized water and styrene-butadiene rubber were adjusted so that the total mass of the finally prepared negative electrode slurry was the same as that of the negative electrode slurry in Example 12. See Table 2 below for details.
  • the preparation method of the negative electrode slurry in Comparative Example 2 is basically the same as the preparation method of the negative electrode slurry in Example 12. The only difference is that the binder composition is not added and styrene-butadiene rubber of the same quality is used instead. At the same time, in Comparative Example 2 By adjusting the addition amounts of deionized water and styrene-butadiene rubber, the total mass of the finally prepared negative electrode slurry is the same as that of the negative electrode slurry in Example 12. See Table 2 below for details.
  • Slurry stability test method Take 4 cups of the slurry in each example and comparative example; take one cup of the slurry and let it stand for 0h, 4h, 8h, 12h, 24h and 48h viscosity, and test the viscosity at different times. ; Then take another two cups of slurry and let it stand for 24h and 48h respectively. Use a steel ruler to scoop out the slurry of different depths and observe the fluidity of the slurry; let the remaining cup of slurry stand for 48h and place the steel ruler vertically along the beaker. Slowly extend the edge into the bottom of the beaker, and slowly scrape it toward the opposite edge. After reaching the edge, slowly pull out the steel ruler, and then check the precipitation brought out by the steel ruler. The specific results are detailed in Table 2 below.
  • Viscosity test method Take the negative electrode slurry from each example and comparative example and dilute it with deionized water until the solid content is 48%. Different rotors correspond to different viscosities. Detection temperature: 25 ⁇ 1°C; Used rotor and speed: 64# rotor, 12r/min, take the 6th minute value; Equipment model: DV-2TLV Brookfield viscometer. The specific results are detailed in Table 2 below.
  • Preparation of the positive electrode sheet Combine the positive active material LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811), the binder polyvinylidene fluoride (PVDF), and the conductive agent acetylene black in a mass ratio of 97%:1.5%:1.5 % is dissolved in the solvent N-methylpyrrolidone (NMP), stir thoroughly and mix evenly to prepare a positive electrode slurry; the positive electrode slurry is evenly coated on the positive electrode current collector aluminum foil, and then dried, cold pressed, and cut. Get the positive electrode piece.
  • NMP N-methylpyrrolidone
  • Isolation film Polyethylene film (PE) with a thickness of 12 ⁇ m is used as the isolation film.
  • the batteries prepared in the above examples and comparative examples were charged with a constant current of 1/3C to 4.25V, then charged with a constant voltage of 4.25V until the current was 0.05C, left for 5 minutes, and then charged with a constant current of 1/3C Discharge to 2.8V, and the resulting capacity is recorded as the initial capacity C0.
  • the measured data is the value of P500.
  • Table 2 The results are detailed in Table 2 below.
  • the negative electrode pieces in the above-mentioned examples and comparative examples as the electrode pieces to be tested, use a blade to cut out electrode piece samples with a width of 0 mm and a length of 100 to 160 mm, and stick the special double-sided tape on them. Place the tape on the steel plate with a width of 20mm and a length of 90-150mm. Paste the intercepted pole piece sample on the double-sided tape with the test side facing down. Then roll it three times in the same direction with a pressure roller to compare the width and pole piece. Insert a paper tape with the same width as the piece sample and 80-200mm longer than the length of the pole piece sample under the pole piece sample, and fix it with wrinkle glue.
  • the indicator light will be on, adjust the limit block to the appropriate position, and move the steel plate
  • One end of the sample without electrode pieces is fixed with the lower clamp. Fold the paper tape upward and fix it with the upper clamp.
  • the tensile rate is 50m/min and the test distance is 50mm.
  • the software takes a data point every 10 seconds to measure the bonding force of the negative electrode piece. The specific results are detailed in Table 2 below.
  • W2 in Table 2 represents the mass ratio between graphite, silicon powder and the binder composition in the negative electrode slurry of Examples 12-34, or the mass ratio of graphite, silicon powder in the negative electrode slurry of Comparative Example 1
  • eta4 represents the viscosity of a solution with a solid content of 1% of the binder composition at 25°C.
  • the water in Table 2 represents the mass of deionized water added for the second time when preparing the negative electrode slurry.
  • the first grafting agent in the binder composition is grafted onto the conductive carbon nanotubes.
  • the first grafting agent can increase the strength of the conductive carbon nanotubes.
  • the steric hindrance enables the conductive carbon nanotubes to be better dispersed, reduces the aggregation of the conductive carbon nanotubes, and improves the stability of the binder composition; the second binder can suspend and further disperse the conductive carbon nanotubes. function to further improve the stability of the adhesive.
  • the above-mentioned modified binder is applied to the negative electrode slurry, which can effectively prevent the negative electrode slurry from gelling, improve the stability of the slurry, and improve the processing performance.
  • grafting the first grafting agent onto the conductive carbon nanotubes can still inhibit the volume expansion of the silicon anode material and will not weaken the cycle of the final secondary battery. performance.
  • Examples 22-26 The main difference between Examples 22-26 is that the adding amounts of the same adhesive composition solution are different.
  • the adding amounts of the adhesive composition solutions from large to small are Example 26, Example 22, Example 25, and Implementation.
  • Example 24 and Example 23 while slight gel appeared in the negative electrode slurry in Example 22, Example 25 and Example 26, but no gel appeared in Example 23 and Example 24.
  • Technical personnel analyzed the reason, which may be because the binder composition in the negative electrode slurry of Example 22, Example 25 and Example 26 was added in a large amount, and the content of conductive carbon nanotubes increased accordingly.
  • the dispersion capacity in the negative electrode slurry is limited and slight interactions between the conductive carbon nanotubes lead to slight gelling.
  • the main difference between Examples 1-3 is that the mass ratio of the modified binder and the second binder in the binder composition is different.
  • the mass ratio of the modified binder and the second binder is 1:( 8-12), the stability of the binder composition can be effectively improved, thereby improving the stability of the negative electrode slurry.
  • Example 1 The main difference between Example 1 and Examples 4-5 is that the mass ratios of acrylic monomers, acrylonitrile monomers, acrylamide monomers and conductive carbon nanotubes used in preparing the modified binder are different.
  • Acrylic acid When the mass ratio of monomers, acrylonitrile monomers, acrylamide monomers and conductive carbon nanotubes is (0.2 ⁇ 0.8):(0 ⁇ 0.18):(0.06 ⁇ 0.18):(0.2 ⁇ 0.6), Increase the steric hindrance of conductive carbon nanotubes.
  • Example 1 The main difference between Example 1 and Examples 6-8 is that the mass percentages of acrylic monomers, acrylonitrile monomers, and acrylamide monomers used in preparing the second adhesive in the total monomers are different.
  • the mass proportion of monomers in the total monomers is 50% to 80%
  • the mass proportion of acrylonitrile monomers in the total monomers is 20% to 40%
  • the mass proportion of acrylamide monomers in the total monomers When the mass ratio is 0% to 20%, the prepared second binder can suspend and further disperse the conductive carbon nanotubes, further improving the stability of the binder.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

本申请涉及一种改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置。其中的改性粘结剂，包括：导电碳纳米管；第一接枝剂，接枝在导电碳纳米管上，第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。

Description

改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置 技术领域
本申请属于二次电池技术领域，具体涉及一种改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置。
背景技术
二次电池因具有重量轻、无污染、无记忆效应等突出特点，被广泛应用于各类消费类电子产品和电动车辆中。随着新能源行业的不断发展，客户对二次电池提出了更高的使用需求。
硅基负极材料因具有较高的容量被广泛使用，但是硅基负极材料导电性差，为了提高硅负极的导电性，通常采用碳纳米管作为导电剂，但是硅负极制备过程中，容易出现负极浆料凝胶等加工问题。
发明内容
鉴于背景技术中存在的技术问题，本申请提供一种改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置，旨在防止负极极片制备过程中出现负极浆料凝胶等问题，提高加工性能。
为了实现上述目的，本申请的第一方面提供一种改性粘结剂，包括：
导电碳纳米管；
第一接枝剂，位于在所述导电碳纳米管上，所述第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
相对于现有技术，本申请至少包括如下所述的有益效果：
本申请的改性粘结剂，其通过将第一接枝剂设置在导电碳纳米管上，第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物，第一接枝剂可增大导电碳纳米管的空间位阻，使导电碳纳米管得到较好分散，减少导电碳纳米管的聚集，改性粘结剂的稳定性好且同 时具有较好的导电性可用作导电剂。如此上述改性粘结剂应用于负极浆料，可有效防止负极浆料凝胶，提高加工性能。
在本申请任意实施方式中，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种；
所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体；可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种；
所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
在本申请任意实施方式中，在25℃时，在25℃时，固含量为0.8％～1.4％的所述改性粘结剂的水溶液的粘度为20000mPa·s～40000mPa·s。
在本申请任意实施方式中，所述第一接枝剂的重均分子量为5000Da～100000Da。
在本申请任意实施方式中，所述导电碳纳米管包括单壁碳纳米管和多壁碳纳米管。
[根据细则91更正 11.08.2023]
在本申请任意实施方式中，所述导电碳纳米管的长度为1μm~5μm
本申请的第二方面提供一种粘结剂组合物，包括本申请第一方面的改性粘结剂；在25℃时，固含量为3％的所述第二粘结剂的粘度为2000mPa·s～7000mPa·s
在本申请任意实施方式中，所述第二粘结剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
在本申请任意实施方式中，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种；
所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体； 可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种；
所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
在本申请任意实施方式中，所述第二粘结剂具有极性基团；
可选地，所述极性基团包括-COOH、CN和酰胺基中的一种或多种。
在本申请任意实施方式中，所述第二粘结剂的重均分子量为50000Da～2000000Da。
在本申请任意实施方式中，所述改性粘结剂和所述第二粘结剂的质量比为1:(8～12)。
在本申请任意实施方式中，在25℃时，固含量为3％的所述粘结剂组合物的水溶液的粘度为15000mPa·s～30000mPa·s。
本申请的第三方面提供一种改性粘结剂的制备方法，包括如下步骤：
丙烯酸类单体、丙烯酰胺类单体和所述导电碳纳米管在含有过硫酸盐的聚乙烯醇纤维素分散液中反应，形成所述改性粘结剂；
可选地，制备所述改性粘结剂的原料还包括丙烯腈类单体。
在本申请任意实施方式中，所述丙烯酸类单体、所述丙烯腈类单体、所述丙烯酰胺类单体和所述导电碳纳米管的质量比为(0.2～0.8):(0～0.18):(0.06～0.18):(0.2～0.6)。
本申请的第四方面提供一种粘结剂组合物的制备方法，包括如下步骤：
S1.采用本申请第三方面提供的方法制备所述改性粘结剂；
S2.采用丙烯酸类单体、丙烯腈类单体制备所述第二粘结剂；
S3.将所述改性粘结剂和所述第二粘结剂混合；
可选地，步骤S2中的制备原料还包括丙烯酰胺类单体。
在本申请任意实施方式中，步骤S2中，丙烯酸类单体在总单体中的质量占比为50％～80％，丙烯腈类单体在总单体中的质量占比为20％～40％，丙烯酰胺类单体在总单体中的质量占比为0％～20％。
本申请的第五方面提供一种负极浆料，包括本申请第一方面的改性粘结剂、本申请第二方面的粘结剂组合物、本申请第三方面的方法制备的改性粘结剂或根据本申请第四 方面的方法制备的粘结剂组合物中的至少一种。
本申请的第六方面提供一种负极极片，包括：
负极集流体；及
负极活性物质层，位于所述负极集流体的至少一个表面上；
其中，所述负极活性物质层包括本申请第一方面的改性粘结剂、本申请第二方面的粘结剂组合物、本申请第三方面的方法制备的改性粘结剂或根据本申请第四方面的方法制备的粘结剂组合物中的至少一种。
在本申请任意实施方式中，所述负极活性物质层还包括第一负极活性物质和第二负极活性物质，所述第一负极活性物质、所述第二负极活性物质和所述粘结剂组合物的质量比为(80～95):(1～20):(0.5～2)。
本申请的第七方面提供一种二次电池，其包括本申请第六方面的负极极片。
本申请的第八方面提供一种电池模块，其包括本申请第七方面的二次电池。
本申请的第九方面提供一种电池包，其包括本申请第八方面的电池模块。
本申请的第十方面提供一种用电装置，其包括本申请第七方面的二次电池、本申请第八方面的电池模块或本申请第九方面的电池包中的至少一种。
附图说明
为了更清楚地说明本申请的技术方案，下面将对本申请中所使用的附图作简单介绍。显而易见地，下面所描述的附图仅仅是本申请的一些实施方式，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
图1是实施例1中的粘结剂组合物的扫描电子显微镜(SEM)图片。
图2是单独的单壁碳纳米管的扫描电子显微镜(SEM)图片。
图3是实施例1中的粘结剂组合物和单独的单壁碳纳米管的电阻率对比图。
图4是实施例12和对比例1中二次电池的循环容量保持率结果示意图；
图5是二次电池的一实施方式的示意图。
图6是图5的分解图。
图7是电池模块的一实施方式的示意图。
图8是电池包的一实施方式的示意图。
图9是图8的分解图。
图10是二次电池用作电源的装置的一实施方式的示意图。
附图标记说明：
1、电池包；2、上箱体；3、下箱体；4、电池模块；5、二次电池；51、壳体；52、电极组件；53、盖板；6、用电装置。
具体实施方式
下面结合具体实施方式，进一步阐述本申请。应理解，这些具体实施方式仅用于说明本申请而不用于限制本申请的范围。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60-120和80-110的范围，理解为60-110和80-120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3，4和5，则下面的范围可全部预料到：1-3、1-4、1-5、2-3、2-4和2-5。在本申请中，除非有其他说明，数值范围“a-b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0-5”表示本文中已经全部列出了“0-5”之间的全部实数，“0-5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
在本文的描述中，需要说明的是，除非另有说明，“以上”、“以下”为包括本数，“一种或几种”中“几种”的含义是两种及两种以上。
如果没有特别的说明，本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有步骤可以顺序进行，也可以随机进行，优选是顺序进行的。例如，所述方法包括步骤(a)和(b)，表示所述方法可包括顺序进行的步骤(a)和(b)，也可以包括顺序进行的步骤(b)和(a)。例如，所述提到所述方法还可包括步骤(c)，表示步骤(c)可以任意顺序加入到所述方法，例如，所述方法可以包括步骤(a)、(b)和(c)， 也可包括步骤(a)、(c)和(b)，也可以包括步骤(c)、(a)和(b)等。
如果没有特别的说明，本申请所提到的“包括”和“包含”表示开放式，也可以是封闭式。例如，所述“包括”和“包含”可以表示还可以包括或包含没有列出的其他组分，也可以仅包括或包含列出的组分。
在本文的描述中，除非另有说明，术语“或(or)”是包括性的。也就是说，短语“A或(or)B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。除非另有说明，本申请中使用的术语具有本领域技术人员通常所理解的公知含义。除非另有说明，本申请中提到的各参数的数值可以用本领域常用的各种测量方法进行测量(例如，可以按照在本申请的实施例中给出的方法进行测试)。
此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括至少一个该特征。在发明的描述中，“多种”的含义是至少两种，例如两种，三种等，除非另有明确具体的限定。在本申请的描述中，“若干”的含义是至少一个，例如一个，两个等，除非另有明确具体的限定。
硅基负极材料因具有较高的容量被广泛使用，但是硅基负极材料导电性差，为了提高硅负极的导电性，通常采用碳纳米管作为导电剂，但是硅负极制备过程中，容易出现负极浆料凝胶等加工问题。本申请的技术人员发现，这主要是因为碳纳米管分散困难，容易聚集，从而导致负极浆料出现凝胶。此外，硅基负极材料在循环过程中体积膨胀、颗粒粉化，导致循环寿命降低，循环性能差。
本申请提供的改性粘结剂，包括：
导电碳纳米管；
第一接枝剂，位于在导电碳纳米管上，第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
不希望限于任何理论，本申请的改性粘结剂，其通过将第一接枝剂设置在导电碳纳米管上，第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物，第一接枝剂可增大导电碳纳米管的空间位阻，使导电碳纳米管得到较好分散，减少导电碳纳米管的聚集，改性 粘结剂的稳定性好且同时具有较好的导电性可用作导电剂。如此上述改性粘结剂应用于负极浆料，可有效防止负极浆料凝胶，提高加工性能。
可理解地，第一接枝剂可以仅包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物，也可以仅包括丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物，还可以同时包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
在其中一些实施例中，第一接枝剂通过加聚反应接枝在导电碳纳米管上。
本发明人经深入研究发现，当本申请的负极活性材料在满足上述设计条件的基础上，若还可选地满足下述条件中的一个或几个时，可以进一步改善负极浆料的加工性能和二次电池的循环性能。
在其中的一些实施例中，丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种。
在其中的一些实施例中，丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体；可选地，丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种。
在其中的一些实施例中，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
在其中的一些实施例中，在25℃时，固含量为0.8％～1.4％的改性粘结剂的水溶液的粘度为20000mPa·s～40000mPa·s；例如，可以为25000mPa·s～40000mPa·s、30000mPa·s～40000mPa·s、35000mPa·s～40000mPa·s或25000mPa·s～35000mPa·s等；进一步地，在25℃时，固含量为1％的改性粘结剂的水溶液的粘度为24000mPa·s～37000mPa·s。
上述提及的改性粘结剂的水溶液的粘度采用如下方法测试得到：称取500g固含量为0.8～1.4％的待测改性粘结剂的水溶液，搅拌溶解2h以使待测改性粘结剂完全稳定均 匀后进行测定，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
在其中的一些实施例中，第一接枝剂的重均分子量为5000Da～100000Da；例如，可以为6000Da～100000Da、7000Da～90000Da、10000Da～80000Da或30000Da～70000Da等。
在其中的一些实施例中，导电碳纳米管包括单壁碳纳米管和多壁碳纳米管。导电碳纳米管具有最高效的导电性，导电率远高于导电炭黑，可在硅负极极片中构建高效导电网络；将含有导电碳纳米管的改性粘结剂用于硅负极时，一方面可有效降低硅负极阻抗，减小极化，提高电子传输能力，减少导电炭黑的用量，进而提高负极活性物质的使用量；另一方面，含有导电碳纳米管的改性粘结剂包覆在负极活性物质表面，可抑制硅材料的膨胀，减少颗粒粉化，延长循环寿命，提高循环性能。进一步地，导电碳纳米管的长度为1μm～5μm；例如，可以为2μm～5μm、3μm～5μm或4μm～5μm等。进一步可选地，导电碳纳米管的长度为3μm～5μm。
本申请实施方式还提供了一种改性粘结剂的制备方法，包括如下步骤：
丙烯酸类单体、丙烯酰胺类单体和导电碳纳米管在含有过硫酸盐的聚乙烯醇纤维素分散液中反应，形成改性粘结剂；
可选地，制备改性粘结剂的原料还包括丙烯腈类单体。
在其中的一些实施方式中，过硫酸盐和导电碳纳米管的质量比为(0.03～0.09):(2～6)；聚乙烯醇纤维素分散液与导电碳纳米管的质量比为(2～6):(0.2～0.6)；进一步地，聚乙烯醇纤维素分散液的浓度为1％。
在其中的一些实施方式中，反应的温度为70℃～80℃；例如，可以为72℃～80℃、75℃～80℃、或73℃～78℃等。反应时间为6h～12h；例如，可以为8h～12h、10h～12h或7～11h等。
在其中的一些实施方式中，丙烯酸类单体、丙烯腈类单体、丙烯酰胺类单体和导电碳纳米管的质量比为(0.2～0.8):(0～0.18):(0.06～0.18):(0.2～0.6)；例如，可以为(0.4～0.8):(0.2～0.18):(0.10～0.18):(0.4～0.6)或(0.3～0.7):(0～0.15):(0.08～0.16):(0.2～0.5)等。
本申请实施方式还提供了一种粘结剂组合物，包括上述的改性粘结剂和第二粘结剂；在25℃时，固含量为3％的第二粘结剂的粘度为2000mPa·s～7000mPa·s；例如，可以为2000mPa·s～7000mPa·s、3000mPa·s～7000mPa·s、4000mPa·s～7000mPa·s 或5000mPa·s～6000mPa·s等。第二粘结剂与改性粘结剂共混后，第二粘结剂可对改性粘结剂中的导电碳纳米管起到悬浮和进一步分散的作用，提高粘结剂组合物的稳定性。进一步地，在25℃时，固含量为3％的第二粘结剂的粘度为5000mPa·s～6500mPa·s。
上述提及的第二粘结剂的粘度采用如下方法测试得到：称取干重15.0g的待测第二粘结剂，加入纯水至待测第二粘结剂和纯水的总重量为500g，搅拌溶解2h以使待测第二粘结剂完全分散均匀后进行测定，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
在其中的一些实施方式中，第二粘结剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
可理解地，第二粘结剂可以仅包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物，也可以仅包括丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物，还可以同时包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
在其中的一些实施方式中，丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种。
在其中的一些实施方式中，丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体；可选地，丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种。
在其中的一些实施方式中，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
在其中的一些实施方式中，第二粘结剂具有极性基团；将第二粘结剂或包含有第二粘结剂的粘结剂组合物用于硅负极时，一方面，极性基团可与集流体表面形成氢键，使第二粘结剂或粘结剂组合物具有良好的粘结性能；另一方面，第二粘结剂或粘结剂组合 物可溶于水，为水溶性粘结剂，应用在硅负极中，易于包覆在负极活性物质颗粒表面，可进一步抑制硅材料的膨胀，减少颗粒粉化，延长循环寿命，提高循环性能。可选地，极性基团包括-COOH、-CN和酰胺基中的一种或多种。进一步可选地，极性基团包括-COOH、-CN中的一种或两种。
在其中的一些实施方式中，第二粘结剂的重均分子量为50000Da～2000000Da；例如，可以为100000Da～2000000Da、500000Da～2000000Da、100000Da～2000000Da或1500000Da～2000000Da等。
在其中的一些实施方式中，改性粘结剂和第二粘结剂的质量比为1:(8～12)；例如，可以为1:(9～12)、1:(10～12)、1:(9.5～11.5)或1:(8～11)等。
在其中的一些实施方式中，在25℃时，固含量为3％的粘结剂组合物的水溶液的粘度为15000mPa·s～30000mPa·s；例如，可以为17000mPa·s～30000mPa·s、20000mPa·s～30000mPa·s、25000mPa·s～30000mPa·s或15000mPa·s～25000mPa·s等。具有高粘度的粘结剂组合物用于硅负极时，可对负极活性物质具有较好的悬浮作用，在制备负极浆料过程中，仅需要少量的羧甲基纤维素钠对负极活性物质进行分散，而无需多的羧甲基纤维素钠维持负极浆料的悬浮性，可进一步提高负极浆料中负极活性物质的含量，同时还可提高负极浆料的粘度稳定性。
上述提及的粘结剂组合物的粘度采用如下方法测试得到：称取500g固含量为3％的待测粘结剂组合物水溶液，搅拌溶解2h以使待测粘结剂组合物完全稳定均匀后进行测定，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
本申请实施方式还提供了一种粘结剂组合物的制备方法，包括如下步骤：
S1.采用上述的改性粘结剂的制备方法制备改性粘结剂；
S2.采用丙烯酸类单体、丙烯腈类单体制备第二粘结剂；
S3.将改性粘结剂和第二粘结剂混合；
可选地，步骤S2中的制备原料还包括丙烯酰胺类单体。
在其中的一些实施方式中，步骤S2中，丙烯酸类单体在总单体中的质量占比为50％～80％，丙烯腈类单体在总单体中的质量占比为20％～40％，丙烯酰胺类单体在总单体中的质量占比为0％～20％。
本申请实施方式还提供了一种负极浆料，包括上述的改性粘结剂、上述的粘结剂组 合物、上述的粘结剂组合物、上述的改性粘结剂的制备方法制备的改性粘结剂或上述的粘结剂组合物的制备方法制备的粘结剂组合物中的至少一种。
本申请实施方式还提供了一种负极浆料的制备方法，包括如下步骤：
将第一负极活性物质、第二负极活性物质、导电剂、羧甲基纤维素钠和第一部分去离子水混合，得第一混合液；
向第一混合液中加入增塑剂、粘结剂组合物、丁苯橡胶和第二部分去离子水，搅拌混合，制得负极浆料。
负极极片
本申请实施方式还提供了一种负极极片，包括：
负极集流体；及
负极活性物质层，位于所述负极集流体的至少一个表面上；
负极活性物质层包括上述的改性粘结剂、上述的粘结剂组合物、上述的粘结剂组合物、上述的改性粘结剂的制备方法制备的改性粘结剂或上述的粘结剂组合物的制备方法制备的粘结剂组合物中的至少一种。
在其中的一些实施方式中，负极活性物质层还包括第一负极活性物质和第二负极活性物质，第一负极活性物质、第二负极活性物质和粘结剂组合物的质量比为(80～95):(1～20):(0.5～2)；例如，可以为(85～95):(4～20):(0.5～1)、(90～95):(1～5):(1～1.5)或(80～90):(3～17):(0.7～1.7)等。
作为示例，第一负极活性物质可以包括以下材料中的至少一种：人造石墨、天然石墨、软炭、硬炭、锡基材料和钛酸锂等；锡基材料可选自单质锡、锡氧化合物以及锡合金中的至少一种。但本申请并不限定于这些材料，还可以使用其他可被用作电池负极活性材料的传统材料。这些负极活性材料可以仅单独使用一种，也可以将两种以上组合使用。
作为示例，第二负极活性物质可选自单质硅、硅氧化合物、硅碳复合物、硅氮复合物以及硅合金中的至少一种。这些负极活性材料可以仅单独使用一种，也可以将两种以上组合使用。
上述提及的第一负极活性物质、第二负极活性物质和粘结剂组合物的质量比可以采用如下方法测得：分别测定负极活性物质层中第一负极活性物质、第二负极活性物质和粘结剂组合物的质量，然后计算三者的比值。
在一些实施方式中，负极活性物质层还可选地包括常规粘结剂。所述常规粘结剂可选自羧甲基纤维素钠(CMC)、丁苯橡胶(SBR)、聚丙烯酸(PAA)、聚丙烯酸钠(PAAS)、聚丙烯酰胺(PAM)、聚乙烯醇(PVA)、海藻酸钠(SA)、聚甲基丙烯酸(PMAA)及羧甲基壳聚糖(CMCS)中的至少一种。
负极活性物质层通常还包括导电剂和其他可选助剂。
作为示例，导电剂可以为超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中一种或几种。
作为示例，其他可选助剂可以是PTC热敏电阻材料等。
负极集流体可以采用常规金属箔片或复合集流体。作为示例，金属箔片可以采用铜箔。复合集流体可包括高分子材料基层和形成于高分子材料基材至少一个表面上的金属层。复合集流体可通过将金属材料(铜、铜合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
作为示例，可以通过以下方式制备负极极片：将上述用于制备负极极片的组分，例如负极活性材料、导电剂、粘结剂和任意其他组分分散于溶剂(例如去离子水)中，形成负极浆料；将负极浆料涂覆在负极集流体上，经烘干、冷压等工序后，即可得到负极极片。
上述原料未特别说明的均可以通过市购获得。
二次电池
二次电池，是指在电池放电后可通过充电的方式使活性材料激活而继续使用的电池。
通常情况下，二次电池包括正极极片、本申请上述提供的负极极片、隔离膜及电解质。在电池充放电过程中，活性离子在正极极片和负极极片之间往返嵌入和脱出。隔离膜设置在正极极片和负极极片之间，起到隔离的作用。电解质在正极极片和负极极片之间起到传导离子的作用。
正极极片
在二次电池中，正极极片通常包括正极集流体及设置在正极集流体至少一个表面上的正极膜层，正极膜层包括正极活性材料。
作为示例，正极集流体具有在其自身厚度方向相对的两个表面，正极膜层设置在正 极集流体相对的两个表面的其中任意一者或两者上。
作为示例，正极集流体可采用金属箔片或复合集流体。例如，作为金属箔片，可采用铝箔。复合集流体可包括高分子材料基层和形成于高分子材料基层至少一个表面上的金属层。复合集流体可通过将金属材料(铝、铝合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
当二次电池为锂离子电池时，正极活性材料可采用本领域公知的用于锂离子电池的正极活性材料。作为示例，正极活性材料可包括以下材料中的至少一种：橄榄石结构的含锂磷酸盐、锂过渡金属氧化物及其各自的改性化合物。但本申请并不限定于这些材料，还可以使用其他可被用作电池正极活性材料的传统材料。这些正极活性材料可以仅单独使用一种，也可以将两种以上组合使用。其中，锂过渡金属氧化物的示例可包括但不限于锂钴氧化物(如LiCoO 2)、锂镍氧化物(如LiNiO 2)、锂锰氧化物(如LiMnO 2、LiMn 2O 4)、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物(如LiNi 1/3Co 1/3Mn 1/3O 2(也可以简称为NCM 333)、LiNi 0.5Co 0.2Mn 0.3O 2(也可以简称为NCM 523)、LiNi 0.5Co 0.25Mn 0.25O 2(也可以简称为NCM 211)、LiNi 0.6Co 0.2Mn 0.2O 2(也可以简称为NCM 622)、LiNi 0.8Co 0.1Mn 0.1O 2(也可以简称为NCM 811)、锂镍钴铝氧化物(如LiNi 0.85Co 0.15Al 0.05O 2)及其改性化合物等中的至少一种。橄榄石结构的含锂磷酸盐的示例可包括但不限于磷酸铁锂(如LiFePO 4(也可以简称为LFP))、磷酸铁锂与碳的复合材料、磷酸锰锂(如LiMnPO 4)、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷酸锰铁锂与碳的复合材料中的至少一种。
当二次电池为钠离子电池时，正极活性材料可采用本领域公知的用于钠离子电池的正极活性材料。作为示例，正极活性材料可以仅单独使用一种，也可以将两种以上组合。其中，正极活性物质可选自钠铁复合氧化物(NaFeO 2)、钠钴复合氧化物(NaCoO 2)、钠铬复合氧化物(NaCrO 2)、钠锰复合氧化物(NaMnO 2)、钠镍复合氧化物(NaNiO 2)、钠镍钛复合氧化物(NaNi 1/2Ti 1/2O 2)、钠镍锰复合氧化物(NaNi 1/2Mn 1/2O 2)、钠铁锰复合氧化物(Na 2/3Fe 1/3Mn 2/3O 2)、钠镍钴锰复合氧化物(NaNi 1/3Co 1/3Mn 1/3O 2)、钠铁磷酸化合物(NaFePO 4)、钠锰磷酸化合物(NaMn PO 4)、钠钴磷酸化合物(NaCoPO 4)、普鲁士蓝类材料、聚阴离子材料(磷酸盐、氟磷酸盐、焦磷酸盐、硫酸盐)等，但本申请并不限定于这些材料，本申请还可以使用其他可被用作钠离子电池正极活性物质的传统公知的材料。
所述正极膜层通常还可选地包括粘结剂、导电剂和其他可选助剂。
作为示例，所述粘结剂可以包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物及含氟丙烯酸酯树脂中的至少一种。
作为示例，所述导电剂可以包括超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
作为示例，可以通过以下方式制备正极极片：将上述用于制备正极极片的组分，例如正极活性材料、导电剂、粘结剂和任意其他的组分分散于溶剂(例如N-甲基吡咯烷酮)中，形成正极浆料；将正极浆料涂覆在正极集流体上，经烘干、冷压等工序后，即可得到正极极片。
隔离膜
在一些实施方式中，二次电池中还包括隔离膜。本申请对隔离膜的种类没有特别的限制，可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔结构隔离膜。
在一些实施方式中，隔离膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。隔离膜可以是单层薄膜，也可以是多层复合薄膜，没有特别限制。在隔离膜为多层复合薄膜时，各层的材料可以相同或不同，没有特别限制。
在一些实施方式中，正极极片、负极极片和隔离膜可通过卷绕工艺或叠片工艺制成电极组件。
电解液
二次电池可以包括电解液，电解液在正极和负极之间起到传导离子的作用。电解液可以包括电解质盐和溶剂。
作为示例，电解质盐可选自六氟磷酸锂(LiPF 6)、四氟硼酸锂(LiBF 4)、高氯酸锂(LiClO 4)、六氟砷酸锂(LiAsF 6)、双氟磺酰亚胺锂(LiFSI)、双三氟甲磺酰亚胺锂(LiTFSI)、三氟甲磺酸锂(LiTFS)、二氟草酸硼酸锂(LiDFOB)、二草酸硼酸锂(LiBOB)、二氟磷酸锂(LiPO 2F 2)、二氟二草酸磷酸锂(LiDFOP)及四氟草酸磷酸锂(LiTFOP)中的一种或几种。
作为示例，所述溶剂可选自碳酸亚乙酯(EC)、碳酸亚丙酯(PC)、碳酸甲乙酯(EMC)、碳酸二乙酯(DEC)、碳酸二甲酯(DMC)、碳酸二丙酯(DPC)、碳酸甲丙酯(MPC)、碳酸乙丙酯(EPC)、碳酸亚丁酯(BC)、氟代碳酸亚乙酯(FEC)、 甲酸甲酯(MF)、乙酸甲酯(MA)、乙酸乙酯(EA)、乙酸丙酯(PA)、丙酸甲酯(MP)、丙酸乙酯(EP)、丙酸丙酯(PP)、丁酸甲酯(MB)、丁酸乙酯(EB)、1,4-丁内酯(GBL)、环丁砜(SF)、二甲砜(MSM)、甲乙砜(EMS)及二乙砜(ESE)中的一种或几种。
在一些实施方式中，电解液中还包括添加剂。例如添加剂可以包括负极成膜添加剂，也可以包括正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温性能的添加剂、改善电池低温性能的添加剂等。
在一些实施方式中，本申请的二次电池为锂离子二次电池。
可以按照本领域常规方法制备二次电池，例如将正极极片、隔离膜、负极极片按顺序卷绕(或叠片)，使隔离膜处于正极极片与负极极片之间起到隔离的作用，得到电芯，将电芯置于外包装中，注入电解液并封口，得到二次电池。
本申请实施例对二次电池的形状没有特别的限制，其可以是圆柱形、方形或其他任意的形状。如图5是作为一个示例的方形结构的二次电池5。
在一些实施例中，二次电池可包括外包装。该外包装可用于封装上述电极组件及电解液。
在一些实施例中，二次电池的外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。二次电池的外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，作为塑料，可列举出聚丙烯、聚对苯二甲酸丁二醇酯以及聚丁二酸丁二醇酯等。
在一些实施例中，参照图6，外包装可包括壳体51和盖板53。其中，壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53能够盖设于所述开口，以封闭所述容纳腔。
正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于所述容纳腔。电解液浸润于电极组件52中。二次电池5所含电极组件52的数量可以为一个或多个，可根据需求来调节。
在一些实施例中，二次电池可以组装成电池模块，电池模块所含二次电池的数量可以为多个，具体数量可根据电池模块的应用和容量来调节。
图7是作为一个示例的电池模块4。在电池模块4中，多个二次电池5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个二次电池5进行固定。
可选地，电池模块4还可以包括具有容纳空间的外壳，多个二次电池5容纳于该容纳空间。
在一些实施例中，上述电池模块还可以组装成电池包，电池包所含电池模块的数量可以根据电池包的应用和容量进行调节。
图8和图9是作为一个示例的电池包1。在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3，上箱体2能够盖设于下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
用电装置
本申请还提供一种用电装置，所述用电装置包括所述的二次电池、电池模块、或电池包中的至少一种。所述二次电池、电池模块或电池包可以用作所述装置的电源，也可以作为所述装置的能量存储单元。所述装置可以但不限于是移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能系统等。
所述装置可以根据其使用需求来选择二次电池、电池模块或电池包。
图10是作为一个示例的用电装置6。该用电装置6为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该装置对二次电池的高功率和高能量密度的需求，可以采用电池包或电池模块。
作为另一个示例的装置可以是手机、平板电脑、笔记本电脑等。该装置通常要求轻薄化，可以采用二次电池作为电源。
以下结合实施例进一步说明本申请的有益效果。
实施例
为了使本申请所解决的技术问题、技术方案及有益效果更加清楚，以下将结合实施例和附图进行进一步详细说明。显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。以下对至少一个示例性实施例的描述实际上仅仅是说明性的，决不作为对本申请及其应用的任何限制。基于本申请中的实施例，本领域普通技术人员在没有付出创造性劳动前提下所获得的所有其他实施例都属于本申请保护的范围。
本申请的实施例中所用的材料均可以通过商购获得。
一、粘结剂组合物的制备
实施例1
1)将44g单壁碳纳米管通过球磨机加工到5μm的长度，加入400g聚乙烯醇纤维素分散液中，再加入0.66g过硫酸铵、52.8g丙烯酸和13.2g丙烯酰胺，在80℃下搅拌反应8h得到改性粘结剂，将改性粘结剂经水洗、离心除杂处理后，加入去离子水稀释得到改性粘结剂固含量为1％的预分散液；
2)将600g丙烯酸、300g丙烯腈、100g丙烯酰胺和0.5g过硫酸铵加入到2000g去离子水中，在80℃下搅拌反应12h，得到第二粘结剂固含量为33.3％的溶液；
3)将2kg的步骤1)中的预分散液与720g步骤2)中的溶液混合，以1200r/min的转速搅拌120min，搅拌罐温度：80℃，加入LiOH溶液调节pH至7后，加入去离子水调节粘结剂组合物固含量为3％，制得含有粘结剂组合物的溶液。其中，改性粘结剂和第二粘结剂的质量比为1:12。
实施例2-11
实施例2-11中粘结剂组合物的制备方法与实施例1中粘结剂组合物的制备方法基本相同，区别仅在于：制备改性粘结剂时各单体的种类及各单体与导电碳纳米管的用量比、制备第二粘结剂时单体的种类及各单体的用量百分比、改性粘结剂与第二粘结剂的质量比中的至少一项不同。具体详见表1。
二、粘结剂组合物性能测试
1.形貌测试方法
将实施例1中制得的粘结剂组合物和单独的单壁碳纳米管分别稀释至单壁碳纳米管的固含量为0.05％，然后分别滴加在铜箔上烘干，用ZEISS sigma 300扫描电子显微镜进行测试，然后参照标准JY/T010-1996进行测试，对样品形貌进行观测。
需要说明的是，实施例1中制得的粘结剂组合物中的粘结剂部分在扫描电镜下观察不到，仅能观察到单壁碳纳米管的形貌。
实施例1的SEM结果如图1所示，单独的单壁碳纳米管的SEM结果如图2所示。由图1和图2可知，实施例1中粘结剂组合物中单壁碳纳米管上的杂质少，分散均匀；而单独的单壁碳纳米管杂质多，单壁碳纳米管之间出现聚集。表明第一接枝剂可增大单壁碳纳米管的空间位阻，第二粘结剂可对单壁碳纳米管起到悬浮和进一步分散的作用， 使导电碳纳米管得到较好分散，减少导电碳纳米管的聚集。
2.粘结剂组合物的电阻率测试方法
将实施例1的粘结剂组合物和单独的单壁碳纳米管分别按单壁碳纳米管的固含量为0.2％、0.1％、0.08％、0.06％、0.04％、0.02％进行逐步稀释，每步稀释后的胶液倒进西林瓶，将浆料电阻仪的电极插入西林瓶中，上中下三个通道均浸没在胶液中，记录上中下三个通道的数据，取平均值。结果如图3所示。
由图3可知，在单壁碳纳米管固含量相同的条件下，实施例1中的粘结剂组合物具有更低的电阻率，导电性更好，且仅需要极少量的粘结剂组合物即可达到构建导电网络的效果。
3.粘度测试方法
取各实施例中含有改性粘结剂的溶液、含有第二粘结剂的溶液和含有粘结剂组合物的溶液进行粘度测定。具体如下：
取各实施例中的含有改性粘结剂的溶液，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
取各实施例中的含有第二粘结剂的溶液，加去离子水稀释至第二粘结剂的固含量为3％，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
取各实施例中的含有粘结剂组合物的溶液，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。
各实施例中部分参数和部分性能测试结果如下表1所示。
表1
Figure PCTCN2022107446-appb-000001
Figure PCTCN2022107446-appb-000002
其中，M11表示制备改性粘结剂时丙烯酸类单体的用量，M12表示制备改性粘结剂时丙烯腈类单体的用量，M13表示制备改性粘结剂时丙烯酰胺类单体的用量，M10表示制备改性粘结剂时导电碳纳米管的用量；η1表示25℃时改性粘结剂固含量为1％的溶液的粘度，η2表示25℃时第二粘结剂固含量为3％的溶液的粘度，η3表示25℃时粘结剂组合物固含量为3％的溶液的粘度；W1表示改性粘结剂和第二粘结剂的质量比。
三、负极浆料的制备
实施例12
将2397g石墨、126g硅粉、13g导电炭黑、8g羧甲基纤维素钠加入最大容量为5L的行星搅拌罐中，公转速度25r/min，自转速度800r/min，搅拌15min；
在行星搅拌罐中加入1253g去离子水，公转速度15r/min，自转速度400r/min，搅拌60min；
在行星搅拌罐中加入49g增塑剂，953g实施例1中的粘结剂组合物，147g去离子水，公转速度25r/min，自转速度1800r/min，搅拌60min；
在搅拌罐中加入49g丁苯橡胶，公转速度25r/min，自转速度800r/min，搅拌30min。
实施例13-34
实施例13-34中负极浆料的制备方法与实施例12中负极浆料的制备方法基本相同，区别仅在于：制备时采用的粘结剂组合物的种类、石墨与硅粉及粘结剂组合物之间的质量比中的至少一项不同；同时实施例13-34中通过调整去离子水和丁苯橡胶的加入量， 以使最后制得的负极浆料的总质量与实施例12中负极浆料的总质量相同。具体详见下表2。
对比例1
对比例1中负极浆料的制备方法与实施例12中负极浆料的制备方法基本相同，区别仅在于：未加入粘结剂组合物，采用聚丙烯酸类粘结剂和单壁碳纳米管替代，水性粘结剂和单壁碳纳米管的质量之和与粘结剂组合物的质量相同，且单壁碳纳米管的质量与粘结剂组合物中含有的单壁碳纳米管的质量相同；同时对比例1中通过调整去离子水和丁苯橡胶的加入量，以使最后制得的负极浆料的总质量与实施例12中负极浆料的总质量相同。具体详见下表2。
对比例2
对比例2中负极浆料的制备方法与实施例12中负极浆料的制备方法基本相同，区别仅在于：未加入粘结剂组合物，采用相同质量的丁苯橡胶替代，同时对比例2中通过调整去离子水和丁苯橡胶的加入量，以使最后制得的负极浆料的总质量与实施例12中负极浆料的总质量相同。具体详见下表2。
四、负极浆料的性能测试
1.浆料稳定性测试方法：取各实施例和对比例中的浆料4杯；各取其中的一杯浆料静置0h，4h，8h，12h，24h和48h粘度，测试不同时间的粘度；再另外取两杯浆料，分别静置24h和48h，分别用钢尺舀取不同深度的浆料，观察浆料的流动性；剩余的一杯浆料静置48h，将钢尺垂直沿烧杯边缘慢慢伸入到烧杯底部，并朝着对面边缘慢慢刮动，到达边缘后慢慢抽出钢尺，然后查看钢尺带出的沉淀情况。具体结果详见下表2。
2.粘度测试方法：取各实施例和对比例中的负极浆料进行，加去离子水稀释至固含量为48％，根据不同转子对应不同的粘度。检测温度：25±1℃；采用转子及转速：64#转子，12r/min，取第6min数值；设备型号：DV-2TLV博勒飞粘度计。具体结果详见下表2。
五、二次电池的制备
1、正极极片的制备：将正极活性材料LiNi 0.8Co 0.1Mn 0.1O 2(NCM811)、粘结剂聚偏氟乙烯(PVDF)、导电剂乙炔黑按照质量比为97％:1.5％:1.5％溶于溶剂N-甲基吡咯烷酮(NMP)中，充分搅拌混合均匀后制备成正极浆料；将正极浆料均匀涂覆在正极集流体铝箔上，之后经过烘干、冷压、分切，得到正极极片。
2、隔离膜：以厚度为12μm的聚乙烯膜(PE)作为隔离膜。
3、电解液的制备：将碳酸亚乙酯(EC)、碳酸甲乙酯(EMC)、碳酸二乙酯(DEC)按体积比1:1:1混合，然后将LiPF6均匀溶解在上述溶液中，得到电解液。该电解液中，LiPF6的浓度为1mol/L。
4、负极极片的制备：将上述各实施例和对比例中的负极浆料分别均匀涂布在铜箔上，经高温烘干，冷压，分切得到负极极片；
5、电芯的制备：将上述正极极片、隔离膜、负极极片及隔离液组装成软包电池。
六、电池性能测试
1.容量保持率测试方法
在25℃下，将上述各实施例和对比例中制备的电池，以1/3C恒流充电至4.25V，再以4.25V恒定电压充电至电流为0.05C，搁置5min，再以1/3C放电至2.8V，所得容量记为初始容量C0。对上述同一个电池重复以上步骤，并同时记录循环第n次后电池的放电容量Cn，则每次循环后电池容量保持率Pn＝Cn/C0*100％；在上述测试条件下循环500次之后测得的数据，即P500的值。结果详见下表2。
实施例12和对比例1中二次电池的循环容量保持率如图4所示，由图4可知，本申请的粘结剂组合物具有与对比例1相当的维持二次电池循环寿命的能力，无恶化。
2.极片粘结力测试方法
在25℃下，分别将上述各实施例和对比例中的负极极片取为待测试极片，用刀片截取宽度为0mm、长度为100～160mm的极片试样，将专用双面胶贴于钢板上，胶带宽度为20mm、长度为90-150mm，将截取的极片试样贴在双面胶上，测试面朝下，后用压辊沿同一个方向滚压三次，将宽度与极片试样等宽，长度大于极片试样长度80～200mm的纸带插入极片试样下方，并且用皱纹胶固定，打开拉力机电源，指示灯亮，调整限位块到合适位置，将钢板未贴极片试样的一端用下夹具固定，将纸带向上翻折，用上夹具固定，利用拉力机附带的手动控制器上的“上行”和“下行”按钮调整上夹具的位置，打开与拉力机链接的专用电脑，双击桌面软件图标，进行测试，拉伸速率为50m/min，测试距离为50mm，软件每10s取一个数据点，测定负极极片的粘结力。具体结果详见下表2。
3.将上述各实施例和对比例制得的二次电池进行25℃下负极极片满充循环膨胀性能测试方法：
在25℃下，将制作好的二次电池以0.5C倍率充电到4.4V后恒压充电至电流低于0.05C，然后使用1C倍率放电至2.8V；将二次电池循环100次后，以1C倍率恒流充电至电压为4.25V，再在4.25V电压下恒压充电至电流小于等于0.05C，之后静置5min，此时电池为满充状态，然后在干燥房中拆解循环后的电池，获得满充循环后的负极极片。
对负极极片进行截面CP表征，测量负极极片的厚度L1，冷压后测得的负极极片的厚度为L0，基于公式(L1-L0)/L1*100计算负极活性物质层的反弹率。
各实施例和对比例中部分参数设置和性能数据如表2所示。
表2
Figure PCTCN2022107446-appb-000003
Figure PCTCN2022107446-appb-000004
其中，表2中W2表示实施例12-34的负极浆料中石墨、硅粉和粘结剂组合物三者之间的质量比，或对比例1的负极浆料中石墨的质量、硅粉的质量与水性粘结剂和单壁碳纳米管的总质量的比例，或对比例2的负极浆料中石墨、硅粉和用于替代粘结剂组合物的丁苯橡胶之间的质量比；η4表示25℃时粘结剂组合物固含量为1％的溶液的粘度。表2中水表示制备负极浆料时，第二次加入的去离子水的质量。
由表1及表2中各实施例和对比例1可知，粘结剂组合物中通过第一接枝剂接枝在导电碳纳米管上，第一接枝剂可增大导电碳纳米管的空间位阻，使导电碳纳米管得到较好分散，减少导电碳纳米管的聚集，提高粘结剂组合物的稳定性；第二粘结剂可对导电碳纳米管起到悬浮和进一步分散的作用，进一步提高粘结剂的稳定性。如此上述改性粘结剂应用于负极浆料，可有效防止负极浆料凝胶，提高浆料稳定性，提升加工性能。同时，与对比例1相比，将第一接枝剂接枝在导电碳纳米管上，仍然可发挥对硅负极材料的体积膨胀抑制作用，并不会减弱最后制得的二次电池的循环性能。
由表1及表2中各实施例和对比例2可知，采用本申请的粘结剂组合物可提高负极浆料的稳定性，改善加工性能，同时可抑制硅负极材料的体积膨胀，进而提升二次电池的循环性能。
实施例22-26的区别主要在于：同一种粘结剂组合物溶液的加入量不同，粘结剂组合物溶液加入量从大至小依次为实施例26、实施例22、实施例25、实施例24、实施例23，而实施例22、实施例25和实施例26中负极浆料均出现轻微凝胶，实施例23和实施例24中未出现凝胶。技术人员分析其原因，这可能是因为实施例22、实施例25和实施例26的负极浆料中粘结剂组合物加入量大，相应地导电碳纳米管含量增加，由于导电碳纳米管在负极浆料中的分散能力有限，导电碳纳米管之间发生轻微相互作用导致轻 微凝胶。
实施例1-3的主要区别在于，粘结剂组合物中改性粘结剂和第二粘结剂的质量比不同，改性粘结剂和第二粘结剂的质量比在1:(8～12)时，可有效提高粘结剂组合物的稳定性，进而提高负极浆料稳定性。
实施例1和实施例4-5的主要区别在于，制备改性粘结剂时采用的丙烯酸类单体、丙烯腈类单体、丙烯酰胺类单体及导电碳纳米管的质量比不同，丙烯酸类单体、丙烯腈类单体、丙烯酰胺类单体及导电碳纳米管的质量比在(0.2～0.8):(0～0.18):(0.06～0.18):(0.2～0.6)时，可增大导电碳纳米管的空间位阻。
实施例1和实施例6-8的主要区别在于，制备第二粘结剂时采用的丙烯酸类单体、丙烯腈类单体、丙烯酰胺类单体占总单体的质量百分比不同，丙烯酸类单体在总单体中的质量占比为50％～80％、丙烯腈类单体在总单体中的质量占比为20％～40％及丙烯酰胺类单体在总单体中的质量占比为0％～20％时，制备得到的第二粘结剂可对导电碳纳米管起到悬浮和进一步分散的作用，进一步提高粘结剂的稳定性。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到各种等效的修改或替换，这些修改或替换都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以权利要求的保护范围为准。

Claims (24)

  1. 一种改性粘结剂，包括：
    导电碳纳米管；
    第一接枝剂，位于所述导电碳纳米管上，所述第一接枝剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
  2. 如权利要求1所述的改性粘结剂，其中，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种；
    所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体；可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种；
    所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
  3. 如权利要求1至2任一项所述的改性粘结剂，其中，在25℃时，固含量为0.8％～1.4％的所述改性粘结剂的水溶液的粘度为20000mPa·s～40000mPa·s。
  4. 如权利要求1至3任一项所述的改性粘结剂，其中，所述第一接枝剂的重均分子量为5000Da～100000Da。
  5. 如权利要求1至4任一项所述的改性粘结剂，其中，所述导电碳纳米管包括单壁碳纳米管和多壁碳纳米管。
  6. 如权利要求1至5任一项所述的改性粘结剂，其中，所述导电碳纳米管的长度为1μm～5μm。
  7. 一种粘结剂组合物，包括如权利要求1至6任一项所述的改性粘结剂和第二粘结剂；
    在25℃时，固含量为3％的所述第二粘结剂的粘度为2000mPa·s～7000mPa·s。
  8. 如权利要求7所述的粘结剂组合物，其中，所述第二粘结剂包括丙烯酸类单体单元-丙烯酰胺类单体单元的共聚物和/或丙烯酸类单体单元-丙烯腈类单体单元-丙烯酰胺类单体单元的共聚物。
  9. 如权利要求8所述的粘结剂组合物，其中，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 6烷基取代的丙烯酸类单体；可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、C 1～C 3烷基取代的丙烯酸类单体；进一步可选地，所述丙烯酸类单体单元对应的单体包括丙烯酸、甲基丙烯酸、乙基丙烯酸及丙基丙烯酸中的一种或多种；
    所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 6烷基取代的丙烯腈类单体；可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、C 1～C 3烷基取代的丙烯腈类单体；进一步可选地，所述丙烯腈类单体单元对应的单体包括丙烯腈、甲基丙烯腈、乙基丙烯腈及丙基丙烯腈中的一种或多种；
    所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 6烷基取代的丙烯酰胺类单体；可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、C 1～C 3烷基取代的丙烯酰胺类单体；进一步可选地，所述丙烯酰胺类单体单元对应的单体包括丙烯酰胺、N，N-二甲基丙烯酰胺、乙基丙烯酰胺、丙基丙烯酰胺中的一种或多种。
  10. 如权利要求7至9任一项所述的粘结剂组合物，其中，所述第二粘结剂具有极性基团；
    可选地，所述极性基团包括-COOH、-CN和酰胺基中的一种或多种。
  11. 如权利要求7至10任一项所述的粘结剂组合物，其中，所述第二粘结剂的重均分子量为50000Da～2000000Da。
  12. 如权利要求7至11任一项所述的粘结剂组合物，其中，所述改性粘结剂和所述第二粘结剂的质量比为1:(8～12)。
  13. 如权利要求7至12任一项所述的粘结剂组合物，其中，在25℃时，固含量为3％的所述粘结剂组合物的水溶液的的粘度为15000mPa·s～30000mPa·s。
  14. 一种权利要求1至6任一项所述的改性粘结剂的制备方法，包括如下步骤：
    丙烯酸类单体、丙烯酰胺类单体和所述导电碳纳米管在含有过硫酸盐的聚乙烯醇纤维素分散液中反应，形成所述改性粘结剂；
    可选地，制备所述改性粘结剂的原料还包括丙烯腈类单体。
  15. 如权利要求14所述的改性粘结剂的制备方法，其中，所述丙烯酸类单体、所述丙烯腈类单体、所述丙烯酰胺类单体和所述导电碳纳米管的质量比为(0.2～0.8):(0～0.18):(0.06～0.18):(0.2～0.6)。
  16. 一种权利要求7至13任一项所述的粘结剂组合物的制备方法，包括如下步骤：
    S1.采用如权利要求14至15任一项所述的方法制备所述改性粘结剂；
    S2.采用丙烯酸类单体、丙烯腈类单体制备所述第二粘结剂；
    S3.将所述改性粘结剂和所述第二粘结剂混合；
    可选地，步骤S2中的制备原料还包括丙烯酰胺类单体。
  17. 如权利要求16所述的粘结剂组合物的制备方法，其中，步骤S2中，丙烯酸类单体在总单体中的质量占比为50％～80％，丙烯腈类单体在总单体中的质量占比为20％～40％，丙烯酰胺类单体在总单体中的质量占比为0％～20％。
  18. 一种负极浆料，包括权利要求1至6任一项所述的改性粘结剂、权利要求7至13任一项所述的粘结剂组合物、权利要求14至15任一项所述的方法制备的改性粘结剂或权利要求16至17任一项所述的方法制备的粘结剂组合物中的至少一种。
  19. 一种负极极片，包括：
    负极集流体；及
    负极活性物质层，位于所述负极集流体的至少一个表面上；
    其中，所述负极活性物质层包括包括权利要求1至6任一项所述的改性粘结剂、权利要求7至13任一项所述的粘结剂组合物、权利要求14至15任一项所述的方法制备的改性粘结剂或权利要求16至17任一项所述的方法制备的粘结剂组合物中的至少一种。
  20. 如权利要求19所述的负极极片，其中，所述负极活性物质层还包括第一负极活性物质和第二负极活性物质，所述第一负极活性物质、所述第二负极活性物质和所述粘结剂组合物的质量比为(80～95):(1～20):(0.5～2)。
  21. 一种二次电池，包括权利要求19～20任一项所述的负极极片。
  22. 一种电池模块，包括权利要求21所述的二次电池。
  23. 一种电池包，包括权利要求22所述的电池模块。
  24. 一种用电装置，包括权利要求21所述的二次电池、权利要求22所述的电池模块或权利要求23所述的电池包中的至少一种。
PCT/CN2022/107446 2022-07-22 2022-07-22 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置 WO2024016331A1 (zh)

Priority Applications (4)

Application Number Priority Date Filing Date Title
PCT/CN2022/107446 WO2024016331A1 (zh) 2022-07-22 2022-07-22 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置
CN202280067750.3A CN118056292A (zh) 2022-07-22 2022-07-22 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置
EP22930177.5A EP4336599A1 (en) 2022-07-22 2022-07-22 Modified binder, binder composition, preparation method, negative electrode slurry, negative electrode sheet, secondary battery, battery module, battery pack, and electrical device
US18/479,949 US20240030451A1 (en) 2022-07-22 2023-10-03 Modified binder, binder composition, preparation method, anode slurry, anode plate, secondary battery, battery module, battery pack and electric device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/107446 WO2024016331A1 (zh) 2022-07-22 2022-07-22 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/479,949 Continuation US20240030451A1 (en) 2022-07-22 2023-10-03 Modified binder, binder composition, preparation method, anode slurry, anode plate, secondary battery, battery module, battery pack and electric device

Publications (1)

Publication Number Publication Date
WO2024016331A1 true WO2024016331A1 (zh) 2024-01-25

Family

ID=89575974

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/107446 WO2024016331A1 (zh) 2022-07-22 2022-07-22 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置

Country Status (4)

Country Link
US (1) US20240030451A1 (zh)
EP (1) EP4336599A1 (zh)
CN (1) CN118056292A (zh)
WO (1) WO2024016331A1 (zh)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1410455A (zh) * 2002-03-14 2003-04-16 四川大学 聚合物/碳纳米管复合乳液及其原位乳液聚合的制备方法
CN102875722A (zh) * 2012-10-06 2013-01-16 四川之江化工新材料有限公司 强力粘合型锂离子电池粘合剂的制备方法
CN109461937A (zh) * 2018-10-19 2019-03-12 深圳市优宝新材料科技有限公司 一种锂电池用三维混合导电粘结剂以及包含该粘结剂的电池
US20210115180A1 (en) * 2019-10-18 2021-04-22 Imam Abdulrahman Bin Faisal University Method of producing a carbon nanotube grafted acrylic acid/acrylamide copolymer nanocomposite sorbent
CN112952092A (zh) * 2019-12-10 2021-06-11 惠州比亚迪电池有限公司 正极粘结剂及其制备方法、正极浆料、正极和锂离子电池
WO2021254245A1 (en) * 2020-06-17 2021-12-23 Guangdong Haozhi Technology Co. Limited Binder composition for secondary battery

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1410455A (zh) * 2002-03-14 2003-04-16 四川大学 聚合物/碳纳米管复合乳液及其原位乳液聚合的制备方法
CN102875722A (zh) * 2012-10-06 2013-01-16 四川之江化工新材料有限公司 强力粘合型锂离子电池粘合剂的制备方法
CN109461937A (zh) * 2018-10-19 2019-03-12 深圳市优宝新材料科技有限公司 一种锂电池用三维混合导电粘结剂以及包含该粘结剂的电池
US20210115180A1 (en) * 2019-10-18 2021-04-22 Imam Abdulrahman Bin Faisal University Method of producing a carbon nanotube grafted acrylic acid/acrylamide copolymer nanocomposite sorbent
CN112952092A (zh) * 2019-12-10 2021-06-11 惠州比亚迪电池有限公司 正极粘结剂及其制备方法、正极浆料、正极和锂离子电池
WO2021254245A1 (en) * 2020-06-17 2021-12-23 Guangdong Haozhi Technology Co. Limited Binder composition for secondary battery

Also Published As

Publication number Publication date
EP4336599A1 (en) 2024-03-13
CN118056292A (zh) 2024-05-17
US20240030451A1 (en) 2024-01-25

Similar Documents

Publication Publication Date Title
CN114730910B (zh) 二次电池及其制备方法与包含二次电池的电池模块、电池包及装置
WO2021109811A1 (zh) 二次电池及含有它的电池模块、电池包和装置
CN113013390B (zh) 一种负极片及锂离子电池
WO2022041259A1 (zh) 二次电池及其制备方法与包含二次电池的电池模块、电池包及装置
Li et al. A new strategy to improve the cyclic stability of high voltage lithium nickel manganese oxide cathode by poly (butyl methacrylate-acrylonitrile-styrene) terpolymer as co-binder in lithium ion batteries
WO2020043151A1 (zh) 正极极片、其制备方法及锂离子二次电池
WO2024082287A1 (zh) 具有改善的电解液粘度和cb值的锂离子电池和用电装置
CN115820047A (zh) 电极极片及其制备方法、电池及用电装置
US20240047683A1 (en) Negative electrode plate, preparation method therefor, secondary battery including same, and power consuming device
WO2022120826A1 (zh) 一种电化学装置和电子设备
US9716264B2 (en) Electrode for lithium secondary battery, method of manufacturing the electrode, and lithium secondary battery including the electrode
WO2023197807A1 (zh) 正极材料及其制备方法、复合正极材料、正极极片及二次电池
EP4224579A1 (en) Positive electrode active material and related electrode sheet, secondary battery, battery module, battery pack, and device
CN115513513A (zh) 二次电池及用电设备
WO2024016331A1 (zh) 改性粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置
WO2024007242A1 (zh) 粘结剂、粘结剂组合物、制备方法、负极浆料、负极极片、二次电池、电池模块、电池包及用电装置
WO2023206140A1 (zh) 二次电池、电池模块、电池包和用电装置
WO2023216130A1 (zh) 一种电解液、二次电池、电池模块、电池包和用电装置
WO2024007183A1 (zh) 一种正极浆料、相应的正极极片、二次电池、电池模块、电池包和用电装置
WO2024082291A1 (zh) 锂离子电池和用电装置
CN114843518B (zh) 负极活性材料、负极活性材料的制备方法及电化学装置
WO2024098411A1 (zh) 正极浆料的制备方法、正极极片、二次电池、电池模块、电池包和用电装置
WO2024055188A1 (zh) 负极极片、二次电池及用电装置
WO2023230985A1 (zh) 锂离子电池正极极片、包含其的锂离子电池及用电装置
WO2024020795A1 (zh) 一种复合正极材料、其制备方法、二次电池、电池模块、电池包和用电装置

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2022930177

Country of ref document: EP

Effective date: 20230915