WO2024031652A1 - 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置 - Google Patents

隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置 Download PDF

Info

Publication number
WO2024031652A1
WO2024031652A1 PCT/CN2022/112165 CN2022112165W WO2024031652A1 WO 2024031652 A1 WO2024031652 A1 WO 2024031652A1 CN 2022112165 W CN2022112165 W CN 2022112165W WO 2024031652 A1 WO2024031652 A1 WO 2024031652A1
Authority
WO
WIPO (PCT)
Prior art keywords
optionally
base film
layer
isolation film
film
Prior art date
Application number
PCT/CN2022/112165
Other languages
English (en)
French (fr)
Inventor
钟韡
葛销明
欧阳楚英
范玉磊
刘锋
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/CN2022/112165 priority Critical patent/WO2024031652A1/zh
Priority to KR1020247002247A priority patent/KR20240024220A/ko
Publication of WO2024031652A1 publication Critical patent/WO2024031652A1/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
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/451—Separators, membranes or diaphragms characterised by the material having a layered structure comprising layers of only organic material and layers containing inorganic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/403—Manufacturing processes of separators, membranes or diaphragms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/431—Inorganic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/431—Inorganic material
    • H01M50/434—Ceramics
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/457—Separators, membranes or diaphragms characterised by the material having a layered structure comprising three or more layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • 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
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present application relates to the technical field of lithium batteries, and in particular to an isolation film, its preparation method, and secondary batteries, battery modules, battery packs and electrical devices using the same.
  • Lithium-ion batteries usually include positive and negative electrode plates, an electrolyte, and an isolation film disposed between the positive and negative electrode plates.
  • the isolation film is mainly used to prevent the positive and negative electrodes from short-circuiting while allowing ions to pass freely.
  • Most of the isolation films used in the prior art are polyolefin films. However, lithium dendrites generated during battery use may penetrate the isolation film, causing a short circuit in the battery and posing a safety risk.
  • This application was made in view of the above problems, and its purpose is to provide an isolation film that can effectively prevent lithium dendrites from penetrating the base film and has low internal resistance.
  • a first aspect of the present application provides an isolation film, including a base film and a coating layer located on the base film.
  • the coating layer includes a ceramic layer partially embedded in the base film and a ceramic layer located on the ceramic layer. Boehmite-like layer.
  • the isolation film described in this application includes a ceramic layer and a boehmite-like layer, which can effectively consume lithium dendrites generated during the use of secondary batteries, prevent them from penetrating the isolation film, and improve the safety performance of the corresponding secondary batteries; more Importantly, by creatively embedding the ceramic layer partially in the base film, a large amount of adhesive can be avoided, thereby effectively reducing the internal resistance of the isolation film.
  • the portion of the ceramic layer embedded in the base film accounts for 5-100%, optionally 10-100%, and more optionally 50-100% of the total thickness of the ceramic layer.
  • the percentage of the ceramic layer embedded in the base film to the total thickness of the ceramic layer is within the above range, it is conducive to better utilizing the molten interface of the base film itself to bond the ceramic particles, reducing the use of binders and reducing isolation. membrane resistance.
  • the coating further includes a thermally conductive layer located on a surface of the boehmite-like layer away from the base film.
  • the existence of the thermal conductive layer is conducive to reducing the occurrence of lithium dendrites from the source and further improving the safety performance of the isolation film.
  • the isolation film meets at least one of the following conditions:
  • the thickness of the ceramic layer is 0.5-10 ⁇ m, optionally 2-7 ⁇ m;
  • the thickness of the base film is 4-20 ⁇ m, optionally 5-12 ⁇ m;
  • the thickness of the boehmite-like layer is 0.5-10 ⁇ m, optionally 2-7 ⁇ m;
  • the thickness of the thermal conductive layer is 0.5-2 ⁇ m, optionally 0.5-1 ⁇ m.
  • the isolation film meets one or more of the above conditions, it is helpful to further improve the safety performance of the isolation film and reduce the internal resistance of the isolation film.
  • the ceramic is selected from one or more of the oxides, nitrides, fluorides or oxo-acid salts of the following elements: Al, Fe, Ti, Co, Zn, Cu , Ni, Mn or Sn;
  • the ceramic is selected from one or more of Fe oxides, Fe oxo acid salts, Ti oxides, Ti oxo acid salts, Zn oxides, NiO, CuO or SnO 2 kind;
  • the ceramic is selected from one or more of Fe 2 O 3 , FePO 4 , TiO 2 , ZnO, Li 4 Ti 5 O 12 , NiO, CuO or SnO 2 .
  • the ceramic is ceramic particles, and the volume average particle diameter Dv50 of the ceramic particles is ⁇ 100 nm, optionally 100 nm-5 ⁇ m, more optionally 200 nm-2 ⁇ m.
  • volume average particle size of the ceramic particles is within the above range, it is beneficial to improve the safety performance of the isolation membrane and reduce the internal resistance of the isolation membrane.
  • the boehmite-like layer is selected from one or more of boehmite, alumina, zirconium oxide or magnesium oxide.
  • the thermal conductivity of the thermal conductive layer is ⁇ 20 W/(m.K);
  • the thermally conductive layer is selected from one or more of boron nitride, tungsten nitride, silicon carbide or aluminum nitride.
  • the thermal conductive layer in the isolation film meets the above conditions, it will help further improve the safety performance of the isolation film and reduce the internal resistance of the isolation film.
  • the base film is selected from polyethylene, polypropylene, polyvinylidene fluoride, aramid, polyethylene terephthalate, polytetrafluoroethylene, polyacrylonitrile, One or more of polyimide, polyamide, polyester or natural fibers;
  • the base film is selected from one or more of polyethylene, polypropylene, polyvinylidene fluoride or polytetrafluoroethylene.
  • the second aspect of the application provides a method for preparing the isolation film described in the first aspect of the application, including the following steps:
  • the mass ratio of the isolation film base film raw material and the pore-forming agent in the mixture in step 1) is 0.1-0.7:1.
  • step 1) optionally further includes the step of passing through a casting chill roll after extrusion.
  • step 2) is performed simultaneously with the passing of the casting cooling roller;
  • step 1) proceed no later than 10s-1h, optionally no later than 1-30min, or optionally proceed to step 2) immediately.
  • step 2) optionally also includes the step of drying over a hot laminating roller or in an oven.
  • step 2) meets one or more of the following conditions:
  • the temperature of the thermal composite roller is 80-190°C, optional 100-180°C;
  • the pressure of the hot composite roller is 5-100Mpa, and 10-50Mpa is optional.
  • a step of stretching the composite base film is further included.
  • a step of extracting the pore-forming agent in the composite base film is further included.
  • a third aspect of the present application provides a secondary battery, including the separator film of the first aspect of the present application or a separator film produced according to the method of the second aspect of the present application.
  • a fourth aspect of the present application provides a battery module including the secondary battery of the third aspect of the present application.
  • a fifth aspect of the present application provides a battery pack, including at least one of the secondary battery of the third aspect of the present application or the battery module of the fourth aspect of the present application.
  • a sixth aspect of the present application provides an electrical device, including at least one of the secondary battery of the third aspect of the present application, the battery module of the fourth aspect of the present application, or the battery pack of the fifth aspect of the present application.
  • the isolation film described in this application includes a ceramic layer partially embedded in a base film.
  • the ceramic layer can better consume lithium dendrites generated during battery use, such as lithium dendrites generated by lithium precipitation or lithium deposition on the surface of the negative electrode, preventing lithium dendrites from piercing the isolation film and improving safety performance.
  • the use of binders can be greatly reduced and the internal resistance of the isolation film can be avoided. Increase.
  • the isolation film of the present application also includes a boehmite-like layer located on the ceramic layer.
  • the boehmite-like layer has good thermal stability. On the one hand, it can block the further growth of lithium dendrites. On the other hand, it can also prevent the reaction between ceramics and metallic lithium on the electrode surface before the lithium dendrites appear, thus preventing lithium from entering the battery. excessive losses.
  • Figure 1 is a schematic diagram of the isolation film of the present application.
  • FIG. 2 is a schematic diagram of a secondary battery according to an embodiment of the present application.
  • FIG. 3 is an exploded view of the secondary battery according to the embodiment of the present application shown in FIG. 2 .
  • Figure 4 is a schematic diagram of a battery module according to an embodiment of the present application.
  • Figure 5 is a schematic diagram of a battery pack according to an embodiment of the present application.
  • FIG. 6 is an exploded view of the battery pack according to an embodiment of the present application shown in FIG. 5 .
  • FIG. 7 is a schematic diagram of a power consumption device using a secondary battery as a power source according to an embodiment of the present application.
  • Ranges 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.
  • ceramic layer is a layer formed of ceramic particles in a statistical sense, relative to the boehmite layer and the thermal conductive layer, and is only for convenience of description. In this application, the ideal state is that the ceramic particles are connected to each other to form a continuous state, in which case the effect of consuming lithium dendrites is better.
  • condition "A or B” is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists) ; Or both A and B are true (or exist).
  • the inventor creatively embedded the ceramic particles partially in the polyolefin base film, and coated the ceramic particles with a boehmite-like layer, thereby effectively preventing lithium dendrites from penetrating the isolation film, and at the same time This makes the internal resistance of the isolation film smaller.
  • the performance of the isolation film can be further improved by further regulating the thickness of the ceramic layer and the boehmite-like layer, and further modifying the isolation film with a thermally conductive layer.
  • a first aspect of the present application provides an isolation film, including a base film and a coating layer located on the base film.
  • the coating layer includes a ceramic layer partially embedded in the base film and a coating layer located on the base film. boehmite-like layer.
  • the isolation film described in this application includes a ceramic layer partially embedded in a base film.
  • the ceramic layer can better consume lithium dendrites generated during battery use, such as lithium dendrites generated by lithium precipitation or lithium deposition on the surface of the negative electrode, preventing lithium dendrites from piercing the isolation film and improving safety performance.
  • the use of binders can be greatly reduced and the internal resistance of the isolation film can be avoided. Increase.
  • the ceramic particles contain many groups that are well compatible with the electrolyte, which is beneficial to reducing the contact angle with the electrolyte, improving the affinity of the base film to the electrolyte, and thereby improving the wettability of the electrolyte to the base film.
  • ceramics have good thermal stability. By compounding ceramics with the base film, the thermal stability of the isolation film can be effectively improved.
  • the isolation film of the present application also includes a boehmite-like layer located on the ceramic layer.
  • the boehmite-like layer has good thermal stability. On the one hand, it can block the further growth of lithium dendrites. On the other hand, it can also prevent the reaction between ceramics and metallic lithium on the electrode surface before the lithium dendrites appear, thus preventing lithium from entering the battery. excessive losses.
  • the ceramic layer contains some or no binder.
  • the amount of binder is 0-10 wt% based on the total weight of the ceramic layer.
  • the amount of binder may range from 0%, 3%, 5%, 7% or 10% and any two of these.
  • the portion of the ceramic layer embedded in the base film accounts for 5-100%, optionally 10-100%, and more optionally 50-100% of the total thickness of the ceramic layer.
  • the thickness of the portion of the ceramic layer embedded in the base film accounts for 5%, 10%, 50%, 70%, 80% or 100% of the total thickness of the ceramic layer, and any two of these ranges.
  • the portion of the ceramic layer embedded in the base film is within the above range, it is beneficial to make better use of the molten interface of the base film itself to bond the ceramic particles, reduce the use of binders, and reduce the internal resistance of the isolation film.
  • the coating further includes a thermally conductive layer located on a surface of the boehmite-like layer away from the base film.
  • the thermal conductive layer is a thin film with high thermal conductivity, such as hexagonal boron nitride (h-BN). Its main function is to provide a uniform thermal field environment, avoid the occurrence of local hot spots, and make the deposition/dissolution of lithium ions uniform. ization, thereby reducing the occurrence of lithium dendrites from the source.
  • the thermal conductive layer can also promote the formation of inorganic SEI (Solid Electrolyte Interface) film, thereby reducing the occurrence of lithium dendrites.
  • the thermally conductive layer is an insulator and does not consume active lithium.
  • the isolation film meets at least one of the following conditions:
  • the thickness of the ceramic layer is 0.5-10 ⁇ m, optionally 2-7 ⁇ m;
  • the thickness of the base film is 4-20 ⁇ m, optionally 5-12 ⁇ m;
  • the thickness of the boehmite-like layer is 0.5-10 ⁇ m, optionally 2-7 ⁇ m;
  • the thickness of the thermal conductive layer is 0.5-2 ⁇ m, optionally 0.5-1 ⁇ m.
  • the isolation film meets one or more of the above conditions, it is helpful to further improve the safety performance of the isolation film and reduce the internal resistance of the isolation film.
  • the ratio of the thickness of the ceramic layer to the boehmite-like layer is 0.05-20, optionally 0.28-3.5.
  • the ratio may be a range of 5:1, 4:1, 3.5:1, 1:1, 1:3.5, 1:4 or 1:5 and any two of these.
  • the ratio of the thickness of the boehmite-like layer to the thermally conductive layer is 0.25-20, optionally 2-14.
  • the above ratio may be a range of 0.5:1, 1:1, 2:1, 2:0.5, 7:1 or 10:1 and any two of these.
  • the thicknesses of the ceramic layer and the boehmite-like layer or the boehmite-like layer and the thermal conductive layer in the isolation film meet the above conditions, it is helpful to further improve the safety performance of the isolation film and reduce the internal resistance of the isolation film.
  • the ceramic is selected from one or more of the oxides, nitrides, fluorides or oxo-acid salts of the following elements: Al, Fe, Ti, Co, Zn, Cu , Ni, Mn or Sn;
  • the ceramic is selected from one or more of Fe oxides, Fe oxo acid salts, Ti oxides, Ti oxo acid salts, Zn oxides, NiO, CuO or SnO 2 kind;
  • the ceramic is selected from one or more of Fe 2 O 3 , FePO 4 , TiO 2 , ZnO, Li 4 Ti 5 O 12 , NiO, CuO or SnO 2 .
  • lithium dendrites will inevitably be produced. If left unchecked, lithium dendrites will eventually contact and puncture the isolation film, causing the positive and negative electrodes to come into contact, causing safety issues.
  • the components contained in the ceramic particles described in this application, such as silicon dioxide, can undergo a lithium insertion reaction and consume the generated lithium dendrites in a timely manner, thereby improving the safety performance of the corresponding battery.
  • reaction mechanism of ceramic particles consuming lithium dendrites described in this application can be divided into alloying reaction mechanism, intercalation reaction mechanism and redox mechanism:
  • Ceramic materials of the intercalation reaction mechanism are mainly SiO 2 , TiO 2 , lithium titanate, etc.
  • Transformation reaction mechanism A redox reaction occurs between metal oxides and Li + to generate metal elements and Li 2 O.
  • the chemical reaction formula is:
  • the ceramics are ceramic particles, and the volume average particle diameter Dv50 of the ceramic particles is ⁇ 100 nm, optionally 100 nm-5 ⁇ m, more optionally 200 nm-2 ⁇ m.
  • the particle size of the ceramic particles is too large, it will be more difficult for the ceramic particles to be embedded in the base film, and "powder falling off” may occur. If the particle size of the ceramic particles is too small, the ceramic particles may block the pores on the surface of the organic microporous material, reducing the air permeability of the isolation membrane, thereby blocking the ion transmission channel, which is not conducive to reducing the internal resistance of the isolation membrane.
  • the boehmite-like layer is selected from one or more of boehmite, alumina, zirconium oxide or magnesium oxide.
  • the thermal conductivity of the thermal conductive layer is ⁇ 20 W/(m.K);
  • the thermally conductive layer is selected from one or more of boron nitride, tungsten nitride, silicon carbide or aluminum nitride.
  • the thermal conductive layer in the isolation film meets the above conditions, it will help further improve the safety performance of the isolation film and reduce the internal resistance of the isolation film.
  • the base film is selected from polyethylene, polypropylene, polyvinylidene fluoride, aramid, polyethylene terephthalate, polytetrafluoroethylene, polyacrylonitrile, One or more of polyimide, polyamide, polyester or natural fibers;
  • the base film is selected from one or more of polyethylene, polypropylene, polyvinylidene fluoride or polytetrafluoroethylene.
  • the isolation film described in the present application can be prepared by methods commonly used in the art. As an example, if a commercial base film is used, the isolation film described in this application can be prepared by the following method:
  • step 2) Evenly disperse the ceramic particles on one surface of the base film A obtained in step 1) to obtain a composite base film;
  • the melting treatment in step 1) refers to heating the isolation film base film to 120-250°C to bring it to a molten state so that it can be extruded.
  • “Sequentially” in step 3) refers to coating the boehmite-like layer first, and then coating the optional thermal conductive material on the surface of the boehmite-like material away from the ceramic layer.
  • the isolation film base film is in a hot-melt state.
  • step 1) after melting treatment, the isolation film base film in a molten state is continuously extruded through a co-extrusion system such as a twin-screw extruder.
  • a co-extrusion system such as a twin-screw extruder.
  • the base film A obtained in step 1) is a cast base film in a hot melt state.
  • step 1) further includes the step of passing through a casting cooling roll after extrusion.
  • the temperature of the casting cooling roller in step 1) is 90-25°C.
  • step 2) is performed simultaneously with the passing of the casting cooling roller;
  • step 1) proceed no later than 10s-1h, optionally no later than 1-30min, or optionally proceed to step 2) immediately.
  • step 2) is performed simultaneously while step 1) passes through the casting cooling roller, that is, dusting or powder spraying is performed while forming the film.
  • the ceramic particles can be uniformly dispersed on one surface of the base film A obtained in step 1) through an online spreading or spraying device.
  • step 2) optionally also includes the step of drying by thermal laminating rollers or in an oven.
  • the temperature of the thermal composite roller or oven in step 2) is 80-190°C, optionally 100-180°C.
  • the pressure of the thermal composite roller in step 2) is 5-100Mpa, optionally 10-50Mpa.
  • step 2) satisfies one or more of the following conditions:
  • the temperature of the thermal composite roller is 80-190°C, optional 100-180°C;
  • the pressure of the hot composite roller is 5-100Mpa, and 10-50Mpa is optional.
  • step 2) before passing through a hot compounding roller, the ceramic particles and the cast base film A obtained in step 1) can be compounded by one or more of the following methods: powder blade coating , spray, solution coating or high-speed powder coating.
  • the boehmite-like particles and the thermally conductive material may be coated by a gravure coating method or a wire rod coating method.
  • the ceramic layer optionally contains only a small amount of binder (usually a polymer).
  • the content of the binder may be 0-10 wt% based on the total weight of the ceramic layer.
  • the binder may be selected from one or more of the following materials: polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene -Tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polyacrylate, fluorinated acrylate, styrene-butadiene rubber, sodium polyacrylate, polymethacrylic acid, polyacrylamide, polyvinyl alcohol, seaweed Sodium phosphate, carboxymethyl chitosan, sodium carboxymethyl cellulose.
  • the ceramic layer does not contain a binder.
  • the release film described in the present application can be prepared by the following method:
  • the melting treatment in step 1) refers to heating the isolation film base film to 120-250°C to bring it to a molten state so that it can be extruded.
  • “Sequentially” in step 3) refers to coating the boehmite-like layer first, and then coating the optional thermal conductive material on the surface of the boehmite-like material away from the ceramic layer.
  • the mass ratio of the isolation film base film raw material and the pore-forming agent in the mixture in step 1) is 0.1-0.7:1.
  • the base film A obtained in step 1) is a cast base film in a hot melt state.
  • step 1) further includes the step of passing through a casting cooling roll after extrusion.
  • the temperature of the casting cooling roller in step 1) is 90-25°C.
  • the pore-forming agent in step 1) can be selected from one of mineral oil, propylene carbonate (i.e., 1,2-propylene glycol carbonate), diethyl carbonate, or ethyl methyl carbonate. kind or variety.
  • step 2) is performed simultaneously with the passing of the casting cooling roller;
  • step 1) proceed no later than 10s-1h, optionally no later than 1-30min, or optionally proceed to step 2) immediately.
  • step 2) means that step 2) is performed simultaneously while step 1) passes through the casting cooling roller, that is, dusting or spraying powder while forming the film.
  • the ceramic particles can be uniformly dispersed on one surface of the base film A through an online spreading or spraying device.
  • the thermal compounding speed of the online spreading or spraying device is 0.5-5.0 m/min, optionally 0.5-2.0 m/min.
  • step 2) optionally also includes the step of drying by thermal laminating rollers or in an oven.
  • the temperature of the thermal composite roller or oven in step 2) is 80-190°C, optionally 100-180°C.
  • the pressure of the thermal composite roller in step 2) is 5-100Mpa, optionally 10-50Mpa.
  • a step of stretching the composite base film is also included.
  • the stretching may be one or more of two-way asynchronous stretching and two-way synchronous stretching.
  • the base film can optionally be stretched according to porosity and strength requirements.
  • a step of extracting the pore-forming agent in the composite base film is also included.
  • the extraction agent used is selected from one or more of dichloromethane, trimethyl phosphate or triethyl phosphate.
  • the boehmite-like particles and the thermally conductive material may optionally be coated by gravure coating or wire rod coating.
  • the isolation film obtained in step 3) is rolled up through a rolling system.
  • the degree of embedding of the ceramic layer in the base film can be adjusted by adjusting the temperature of the thermal laminating roller and oven and the coating amount.
  • a second aspect of the present application provides a secondary battery, which includes the isolation film described in the first aspect of the present application.
  • a secondary battery in addition to a separator, includes a positive electrode plate, a negative electrode plate, and an electrolyte.
  • this application can also be used in lithium metal batteries to replace traditional separators.
  • the negative electrode can be lithium metal or lithium alloy, or there can be no negative electrode.
  • the corresponding cathode materials are as described above. If it is a lithium metal battery without anode, the cathode material needs to provide a lithium source.
  • the preparation of the secondary battery can be carried out by methods commonly used in the art.
  • the positive electrode sheet, the negative electrode sheet and the separator can be made into an electrode assembly through a winding process or a lamination process, and then the electrolyte is injected into the electrode assembly. and sealed to prepare a secondary battery.
  • the secondary batteries described in this application include button batteries.
  • the materials of the positive electrode piece and the negative electrode piece may be the same or different.
  • the button battery can be prepared by a method commonly used by those skilled in the art.
  • the positive electrode piece, the separator film and the negative electrode piece can be assembled into an electrode assembly, and then the electrolyte is injected into the electrode assembly and sealed to form a button cell.
  • the positive electrode sheet 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 current collector has two surfaces facing each other 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 be 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 substrate and a metal layer formed on at least one surface of the polymer material substrate.
  • 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 material is a compound that can reversibly intercalate and deintercalate Li+.
  • the cathode active material may be a cathode active material known in the art for batteries.
  • Examples include lithium-containing composite oxides represented by Li x MO 2 or Li y M 2 O 4 (where M is a transition metal, 0 ⁇ x ⁇ 1, 0 ⁇ y ⁇ 2), and spinel-like oxides.
  • Examples include lithium cobalt oxides such as LiCoO2 , lithium manganese oxides such as LiMn2O4 , lithium nickel oxides such as LiNiO2 , lithium titanium oxides such as Li4 / 3Ti5/ 3O4 , and lithium manganese nickel.
  • Composite oxide, lithium manganese nickel cobalt composite oxide; materials with olivine crystal structure such as LiMPO 4 (M Fe, Mn, Ni), etc.
  • the cathode active material is a lithium-containing composite oxide with a layered structure or a spinel-like structure, such as LiCoO 2 , LiMn 2 O 4 , LiNiO 2 , LiNi 1/2 Mn 1/ Lithium manganese nickel composite oxide represented by LiNi 1/3 Mn 1/3 Co 1/3 O 2 , LiNi 0.6 Mn 0.2 Co 0.2 O 2, etc., Or LiNi 1-xyz Co x Al y Mg z O 2 (in the formula, 0 ⁇ x ⁇ 1, 0 ⁇ y ⁇ 0.1, 0 ⁇ z ⁇ 0.1, 0 ⁇ 1-xyz ⁇ 1) and other lithium-containing composite oxides.
  • lithium-containing composite oxides in which part of the constituent elements in the above-mentioned lithium-containing composite oxide is replaced by additional elements such as Ge, Ti, Zr, Mg, Al, Mo, and Sn are also included in the scope of the present application.
  • positive electrode active materials In addition to the above-mentioned positive electrode active materials, other conventional materials that can be used as positive electrode active materials of batteries may 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. For example, by simultaneously using a lithium-containing composite oxide with a layered structure and a lithium-containing composite oxide with a spinel structure, it is possible to achieve both increased capacity and improved safety.
  • the positive electrode film layer optionally further includes a conductive agent.
  • 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 conductive agent accounts for 0.05-5%, optionally 0.5-3%, of the total weight of the positive electrode film layer.
  • the positive electrode membrane layer optionally further includes a binder, such as polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoroethylene Binders commonly used in the battery field include propylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and polyethylene oxide.
  • a binder such as polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoroethylene Binders commonly used in the battery field include propylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and polyethylene oxide.
  • the binder accounts for 0.1-3.5%, optionally 0.5-2.5%, of the total weight of the positive electrode film layer.
  • the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, binder and any other components in a solvent (such as N -methylpyrrolidone) 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 -methylpyrrolidone
  • the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector.
  • the negative electrode current collector has two opposite surfaces in its own thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.
  • the negative electrode current collector may be a metal foil or a composite current collector.
  • the metal foil copper foil can be used.
  • the composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate.
  • 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 material is a compound capable of intercalating and deintercalating lithium metal and lithium.
  • the negative active material may be a negative active material known in the art for batteries.
  • various materials such as alloys of aluminum, silicon, and tin, or oxides, and carbon materials can be used as the negative electrode active material.
  • examples of the oxide include titanium dioxide
  • examples of the carbon material include graphite, pyrolytic carbons, cokes, glassy carbons, fired bodies of organic polymer compounds, mesophase carbon beads, and the like.
  • the tin-based material may be selected from at least one of elemental tin, tin oxide compounds and tin alloys.
  • 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 negative electrode film layer optionally further includes a conductive agent.
  • the conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the conductive agent accounts for 0.05-5%, optionally 0.5-3%, of the total weight of the negative electrode film layer.
  • the negative electrode film layer optionally further includes a binder, such as polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoroethylene Binders commonly used in the battery field include propylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and polyethylene oxide.
  • a binder such as polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoroethylene Binders commonly used in the battery field include propylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and polyethylene oxide.
  • the binder accounts for 0.1-3.5%, optionally 0.5-2.5%, of the total weight of the negative electrode film layer.
  • the negative electrode film layer optionally includes other auxiliaries, such as thickeners (such as sodium carboxymethylcellulose (CMC-Na)) and the like.
  • thickeners such as sodium carboxymethylcellulose (CMC-Na)
  • the negative electrode sheet can be prepared by dispersing the above-mentioned components for preparing the negative electrode sheet, such as negative active materials, conductive agents, binders 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
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the type of electrolyte in this application can be selected according to needs.
  • the electrolyte can be liquid, gel, or completely solid.
  • the electrolyte is an electrolyte solution.
  • the electrolyte solution includes electrolyte salts and solvents.
  • a non-aqueous solvent (organic solvent) is used as the non-aqueous electrolyte solution.
  • Non-aqueous solvents include carbonates, ethers, etc.
  • carbonates include cyclic carbonates and chain carbonates.
  • cyclic carbonates include ethylene carbonate, propylene carbonate, butylene carbonate, ⁇ -butyrolactone, sulfur esters (ethylene glycol sulfide), and the like.
  • chain carbonates include low-viscosity polar chain carbonates and aliphatic branched carbonate compounds, such as dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.
  • a mixed solvent of cyclic carbonate (especially ethylene carbonate) and linear carbonate is particularly preferred.
  • ethers examples include tetraethylene glycol dimethyl ether (TEGDME), ethylene glycol dimethyl ether (DME), 1,3-dioxopentane (DOL), and the like.
  • TEGDME tetraethylene glycol dimethyl ether
  • DME ethylene glycol dimethyl ether
  • DOL 1,3-dioxopentane
  • chain alkyl esters such as methyl propionate, chain phosphate triesters such as trimethyl phosphate, nitrile solvents such as 3-methoxypropionitrile, and dendritic solvents can also be used.
  • the compound is a non-aqueous solvent (organic solvent) such as a branched compound having an ether bond.
  • fluorine-based solvents can also be used.
  • fluorine-based solvents examples include H(CF 2 ) 2 OCH 3 , C 4 F 9 OCH 3 , H(CF 2 ) 2 OCH 2 CH 3 , H(CF 2 ) 2 OCH 2 CF 3 , H( CF 2 ) 2 CH 2 O (CF 2 ) 2 H, etc., or CF 3 CHFCF 2 OCH 3 , CF 3 CHFCF 2 OCH 2 CH 3 and other straight-chain (perfluoroalkyl) alkyl ethers, such as 2-tris Fluoromethyl hexafluoropropyl methyl ether, 2-trifluoromethyl hexafluoropropyl ethyl ether, 2-trifluoromethyl hexafluoropropyl propyl ether, 3-trifluoromethyl octafluorobutyl methyl ether, 3-trifluoromethyl ether Methyl octafluorobutyl ether, 3-trifluoromethyl oc
  • lithium salts such as lithium perchlorate, organoboron lithium salt, lithium salt of fluorine-containing compound, and lithium imide salt are preferred.
  • electrolyte salts examples include LiClO 4 , LiPF 6 , LiBF 4 , LiAsF 6 , LiSbF 6 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiC 2 F 4 (SO 3 ) 2 , LiN( C 2 F 5 SO 2 ) 2 , LiC(CF 3 SO 2 ) 3 , LiC n F 2n+1 SO 3 (n ⁇ 2), LiN(R f OSO 2 ) 2 (where R f is a fluoroalkyl group )wait.
  • fluorine-containing organic lithium salts are particularly preferred. Fluorine-containing organic lithium salts are easily soluble in non-aqueous electrolytes because they are highly anionic and easily separated into ions.
  • the concentration of the electrolyte lithium salt in the non-aqueous electrolyte is, for example, above 0.3 mol/L (mol/L), more preferably above 0.7 mol/L; below 1.7 mol/L, more preferably below 1.2 mol/L. .
  • concentration of the electrolyte lithium salt is too low, the ionic conductivity is too small.
  • concentration of the electrolyte lithium salt is too high, there is a concern that the incompletely dissolved electrolyte salt may precipitate.
  • the electrolyte may optionally include additives, which are not specifically limited in this application.
  • 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 battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.
  • a third aspect of the present application provides a battery module including the secondary battery of the second aspect of the present application.
  • the battery module can be prepared by methods commonly used in the art.
  • a fourth aspect of the application provides a battery pack, including the battery module of the third aspect of the application.
  • the battery pack can be prepared by methods commonly used in the art.
  • a fifth aspect of the present application provides an electrical device, including at least one selected from the secondary battery of the second aspect of the present application, the battery module of the third aspect of the present application, or the battery pack of the fourth aspect of the present application. kind.
  • 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 plastic include polypropylene, polybutylene terephthalate, polybutylene succinate, and the like.
  • FIG. 2 shows a square-structured secondary battery 5 as an example.
  • 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 those skilled in the art can select according to specific actual needs.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery module.
  • FIG. 4 is a battery module 3 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.
  • the number of battery modules contained in the battery pack can be one or more. Those skilled in the art can select the specific number 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 disposed 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 provided by the present application.
  • the secondary battery, battery module, or battery pack may be used as a power source for the electrical device, or may be used as an energy storage unit for the electrical device.
  • the electric device may include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, and electric golf carts). , electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited to these.
  • a secondary battery, a battery module or a battery pack can be selected according to its usage requirements.
  • Fig. 7 is an electrical device as an example.
  • the electric device is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc.
  • a battery pack or battery module 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 2) In the process of forming the cast base film A through the cast cooling roller in step 1), ZnO particles with a volume average particle size Dv50 of 100 nm are uniformly dispersed on one surface of the cast base film A simultaneously through an online spraying device. , and then thermally composite the cast base film A and the ceramic through a thermal composite roller.
  • the thermal composite temperature is 170°C
  • the pressure is 10MPa
  • the speed is 1.5m/min;
  • alumina a mixture of alumina and binder (polyacrylate, number average molecular weight 9000) with a weight ratio of 0.91:0.04 in deionized water to form a slurry with a solid content of 35%) Dispersed on the ceramic layer, the coating thickness after drying is 2 ⁇ m;
  • Example 2-22 and Comparative Examples 1-3 are similar to Example 1. Please refer to Table 1 for details.
  • the temperatures/pressures of the thermal composite rollers in Examples 7-9 are 110°C/0.8MPa, 110°C/5MPa and 140°C/7MPa respectively.
  • Both the positive and negative electrodes use lithium sheets with a diameter ( ⁇ ) of 18 mm and a thickness of 250 ⁇ m.
  • the interlayer is the isolation film prepared in the Examples and Comparative Examples. Then add an appropriate amount of electrolyte (just make sure the pole piece and separator are completely infiltrated) and assemble it into a 2430 button battery.
  • the electrolyte is prepared by the following method: mix ethylene carbonate (EC) and dimethyl carbonate (DMC) at a volume ratio of 1:1, then add LiPF 6 and stir evenly so that the concentration of LiPF6 is 1 mol/ L.
  • Dv50 The diameter of particles accounting for 50% of the total volume is greater than this value, and the diameter of particles accounting for 50% of the total volume is smaller than this value.
  • Dv50 represents the median particle size of the powder
  • the angle of the scattered light is inversely proportional to the diameter of the particle.
  • the intensity of the scattered light attenuates logarithmically as the angle increases.
  • the energy distribution of the scattered light is directly related to the distribution of the particle diameter.
  • Test process Discharge the button cell at a constant current of 1mA/ cm2 to 100mV, let it rest for 10 minutes, and then maintain it at a constant voltage of 100mV for 5 days. Record the time when the peak current of 200-600mA stably appears as the time for the battery system to operate safely and normally, which is the short circuit occurrence time in Table 1.
  • Test process Make a laminated symmetrical battery with an isolation film.
  • the anode plate uses a conventional graphite pole plate, a Cu plate is used as a current collector, and the electrolyte is the same as the button cell electrolyte.
  • the frequency range of the AC impedance spectrum test is 1MHz ⁇ 1kHz, and the amplitude is 5mV.
  • the isolation film resistance R ⁇ L/S*n (L, S, n are the thickness, area and number of layers of the isolation film in the test respectively), the ion conductivity (mS/cm) of the isolation film can be obtained.
  • the secondary battery using the separator described in the present application has better safety performance and higher ionic conductivity.
  • the possible reason is that the isolation film described in this application can effectively consume lithium dendrites and prevent the dendrites from penetrating the isolation film and causing a short circuit, thereby improving the safety performance of the isolation film; at the same time, the higher ionic conductivity It shows that the internal resistance of the isolation film is small, indicating that the technical solution of the present application can simultaneously achieve a lower internal resistance of the isolation film.
  • Table 1 it can be seen from Table 1 that by adjusting the type of ceramic particles and the thickness of each layer, the safety performance of the isolation membrane can be further improved and the internal resistance of the isolation membrane can be reduced.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Cell Separators (AREA)
  • Secondary Cells (AREA)

Abstract

本申请提供一种隔离膜，包括基膜和位于所述基膜上的涂层，所述涂层包括部分内嵌在所述基膜中的陶瓷层和位于所述陶瓷层上的类勃姆石层。本申请所述隔离膜可有效消耗锂枝晶，避免其刺透隔离膜，同时具备较低的内阻。本申请还提供所述隔离膜的制备方法以及使用所述隔离膜的二次电池、电池模块、电池包和用电装置。

Description

隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置 技术领域
本申请涉及锂电池技术领域，尤其涉及一种隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置。
背景技术
近年来，随着锂离子电池的应用范围越来越广泛，锂离子电池在风力、火力、水力、太阳能电站等储能系统以及电动工具、电动自行车等多个领域得到了非常广泛的应用。锂离子电池通常包括正负极极片、电解液和设置在正负极极片之间的隔离膜，所述隔离膜主要用于防止正负极短路，同时使离子自由通过。现有技术中使用的隔离膜多为聚烯烃膜。然而，在电池使用过程中产生的锂枝晶可能刺透隔离膜，从而造成电池短路，引发安全风险。
为解决上述问题，技术人员通常会在隔离膜上施加无机涂层来避免锂枝晶刺透隔离膜。然而，在施加无机涂层时，往往需要使用大量的粘结剂，导致隔离膜内阻增大。
由此可见，如何开发出一种同时具备良好的安全性能和较低内阻的隔离膜仍是研发人员亟需解决的一项课题。
发明内容
本申请是鉴于上述课题而进行的，其目的在于，提供一种隔离膜，所述隔离膜可有效避免锂枝晶刺透基膜且具有较低的内阻。
本申请第一方面提供一种隔离膜，包括基膜和位于所述基膜上的涂层，所述涂层包括部分内嵌在所述基膜中的陶瓷层和位于所述陶瓷层上的类勃姆石层。
在本申请所述隔离膜中包括陶瓷层和类勃姆石层，可有效消耗二 次电池使用过程中产生的锂枝晶，避免其刺透隔离膜，提升对应二次电池的安全性能；更重要的是，通过创造性地将陶瓷层部分内嵌在基膜中，可避免大量使用粘结剂，从而有效降低了隔离膜内阻。
在任意实施方式中，可选地，所述陶瓷层内嵌在基膜中的部分占陶瓷层总厚度的5-100％、可选10-100％、更可选50-100％。
当陶瓷层内嵌在基膜中的部分占陶瓷层总厚度的百分比在上述范围内时，有利于较好地利用基膜自身的熔融界面粘结陶瓷颗粒，减少粘结剂的使用，降低隔离膜内阻。
在任意实施方式中，可选地，所述涂层还包括位于所述类勃姆石层的远离所述基膜的表面上的导热层。
导热层的存在有利于从源头上减少锂枝晶的出现，进一步改善隔离膜的安全性能。
在任意实施方式中，可选地，所述隔离膜满足下述条件中的至少一个：
(1)所述陶瓷层的厚度为0.5-10μm、可选为2-7μm；
(2)所述基膜的厚度为4-20μm、可选为5-12μm；
(3)所述类勃姆石层的厚度为0.5-10μm、可选为2-7μm；以及
(4)所述导热层的厚度为0.5-2μm、可选为0.5-1μm。
当隔离膜满足上述条件中的一个或多个时，有利于进一步提升隔离膜的安全性能，并降低隔离膜的内阻。
在任意实施方式中，可选地，所述陶瓷选自以下元素的氧化物、氮化物、氟化物或含氧酸盐中的一种或多种：Al、Fe、Ti、Co、Zn、Cu、Ni、Mn或Sn；
可选地，所述陶瓷选自Fe的氧化物、Fe的含氧酸盐、Ti的氧化物、Ti的含氧酸盐、Zn的氧化物、NiO、CuO或SnO 2中的一种或多种；
更可选地，所述陶瓷选自Fe 2O 3、FePO 4、TiO 2、ZnO、Li 4Ti 5O 12、NiO、CuO或SnO 2中的一种或多种。
在任意实施方式中，可选地，所述陶瓷为陶瓷颗粒，所述陶瓷颗 粒的体积平均粒径Dv50≥100nm，可选为100nm-5μm，更可选为200nm-2μm。
当陶瓷颗粒的体积平均粒径在上述范围内时，有利于提升隔离膜的安全性能，并降低隔离膜的内阻。
在任意实施方式中，可选地，所述类勃姆石层选自勃姆石、氧化铝、氧化锆或氧化镁中的一种或多种。
在任意实施方式中，可选地，所述导热层的导热系数≥20W/(m.K)；
可选地，所述导热层选自氮化硼、氮化钨、碳化硅或氮化铝中的一种或多种。
当隔离膜中的导热层满足上述条件时，有利于进一步提升隔离膜的安全性能，并降低隔离膜的内阻。
在任意实施方式中，可选地，所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯、芳纶、聚对苯二甲酸乙二醇酯、聚四氟乙烯、聚丙烯腈、聚酰亚胺、聚酰胺、聚酯或天然纤维中的一种或多种；
可选地，所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯或聚四氟乙烯中的一种或多种。
本申请的第二方面提供一种制备本申请第一方面所述隔离膜的方法，包括以下步骤：
1)对包含隔离膜基膜原材料、成孔剂的混合物进行熔融处理，然后经挤出形成基膜A；
2)将陶瓷颗粒均匀分散在基膜A的一个表面上，得到复合基膜；和
3)依次将类勃姆石颗粒和可选地导热材料均匀涂布在步骤2)所得复合基膜上。
在任意实施方式中，可选地，步骤1)所述混合物中隔离膜基膜原材料与成孔剂的质量比为0.1-0.7∶1。
在任意实施方式中，可选地，步骤1)还包括在挤出后通过流延冷却辊的步骤。
在任意实施方式中，可选地，步骤2)与所述通过流延冷却辊同步进行；或者
在进行步骤1)后，不晚于10s-1h、可选不晚于1-30min、更可选立即进行步骤2)。
在任意实施方式中，可选地，步骤2)还包括通过热复合辊或在烘箱中干燥的步骤。
在任意实施方式中，可选地，步骤2)满足以下条件中的一个或多个：
(1)热复合辊的温度为80-190℃，可选100-180℃；
(2)热复合辊的压力为5-100Mpa，可选10-50Mpa。
在任意实施方式中，可选地，在进行步骤2)之后和在进行步骤3)之前，还包括对复合基膜进行拉伸的步骤。
在任意实施方式中，可选地，在对复合基膜进行拉伸之后，还包括将复合基膜中的成孔剂萃取出来的步骤。
本申请的第三方面提供一种二次电池，包括本申请第一方面的隔离膜或根据本申请第二方面的方法制得的隔离膜。
本申请的第四方面提供一种电池模块，包括本申请的第三方面的二次电池。
本申请的第五方面提供一种电池包，包括本申请的第三方面的二次电池或本申请第四方面的电池模块中的至少一种。
本申请的第六方面提供一种用电装置，包括本申请的第三方面的二次电池、本申请第四方面的电池模块或本申请的第五方面的电池包中的至少一种。
[有益效果]
本申请所述隔离膜包括部分内嵌在基膜中的陶瓷层。陶瓷层可较好地消耗电池使用过程中产生的锂枝晶，例如负极表面析锂或锂沉积而产生的锂枝晶，避免锂枝晶刺穿隔离膜，提升安全性能。同时，通过创造性地将陶瓷层部分内嵌在基膜中，利用隔离膜基膜自身熔融界面的粘结，实现对陶瓷颗粒的束缚，可大大减少粘结剂的使用，避免 隔离膜内阻大幅增加。
本申请所述隔离膜还包括位于所述陶瓷层上的类勃姆石层。类勃姆石层具有良好的热稳定性，其一方面可以阻挡锂枝晶的进一步生长，另一方面也可在锂枝晶出现前，防止陶瓷与电极表面金属锂的反应，避免电池中锂的过度损失。
附图说明
图1为本申请隔离膜的示意图。
图2是本申请一实施方式的二次电池的示意图。
图3是图2所示的本申请一实施方式的二次电池的分解图。
图4是本申请一实施方式的电池模块的示意图。
图5是本申请一实施方式的电池包的示意图。
图6是图5所示的本申请一实施方式的电池包的分解图。
图7是本申请一实施方式的二次电池用作电源的用电装置的示意图。
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顶盖组件；11基膜；12陶瓷层；13类勃姆石层；14导热层
具体实施方式
以下，适当地参照附图详细说明具体公开了本申请的隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置的实施方式。但是会有省略不必要的详细说明的情况。例如，有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长，便于本领域技术人员的理解。此外，附图及以下说明是为了本领域技术人员充分理解本申请而提供的，并不旨在限定权利要求书所记载的主题。
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。
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。
需要说明的是，在本申请中，并非所有内嵌在基膜中的陶瓷颗粒均处于由陶瓷颗粒物理上相互连接而形成的连续状态，陶瓷颗粒也可能处于离散状态。术语“陶瓷层”是统计学意义上由陶瓷颗粒形成的层， 是相对于勃姆石层和导热层而言的，仅是为了便于描述。在本申请中，理想状态是陶瓷颗粒相互连接形成连续状态，此时消耗锂枝晶的效果较好。
如果没有特别的说明，在本申请中，术语“或”是包括性的。举例来说，短语“A或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)。
发明人在实际工作中发现，现有技术为避免锂枝晶刺透隔离膜，进而引发安全风险，通常会在聚烯烃膜表面施加无机涂层。然而，为避免无机颗粒“掉粉”，往往需要使用大量的粘结剂，这会导致隔离膜的内阻显著增大。
在经过大量研究后，发明人创造性地将陶瓷颗粒部分内嵌在聚烯烃基膜中，并在陶瓷颗粒上涂布一层类勃姆石层，从而有效避免锂枝晶刺透隔离膜，同时使得隔离膜的内阻较小。此外，通过进一步调控陶瓷层和类勃姆石层的厚度，以及通过导热层对隔离膜作进一步修饰，可以进一步改善隔离膜性能。
[隔离膜]
本申请的第一方面提供一种隔离膜，包括基膜和位于所述基膜上的涂层，所述涂层包括部分内嵌在所述基膜中的陶瓷层和位于所述基膜上的类勃姆石层。
本申请所述隔离膜包括部分内嵌在基膜中的陶瓷层。陶瓷层可较好地消耗电池使用过程中产生的锂枝晶，例如负极表面析锂或锂沉积而产生的锂枝晶，避免锂枝晶刺穿隔离膜，提升安全性能。同时，通过创造性地将陶瓷颗粒部分内嵌在基膜中，利用隔离膜基膜自身熔融界面的粘结，实现对陶瓷颗粒的束缚，可大大减少粘结剂的使用，避免隔离膜内阻大幅增加。此外，所述陶瓷颗粒包含许多与电解液兼容性较好的基团，有利于减小与电解液的接触角，提高基膜对电解液的 亲和力，进而提高电解液对基膜的浸润性。另外，陶瓷具有较好的热稳定性，通过将陶瓷与基膜复合，可以有效提高隔离膜的热稳定性。
本申请所述隔离膜还包括位于所述陶瓷层上的类勃姆石层。类勃姆石层具有良好的热稳定性，其一方面可以阻挡锂枝晶的进一步生长，另一方面也可在锂枝晶出现前，防止陶瓷与电极表面金属锂的反应，避免电池中锂的过度损失。
在一些实施方式中，可选地，所述陶瓷层含部分粘结剂或不含粘结剂。
在一些实施方式中，可选地，基于所述陶瓷层的总重量计，粘结剂的用量为0-10wt％。作为示例，粘结剂的用量可为0％、3％、5％、7％或10％以及这些中的任意两者所组成的范围。
在一些实施方式中，可选地，所述陶瓷层内嵌在基膜中的部分占陶瓷层总厚度的5-100％、可选10-100％、更可选50-100％。作为示例，陶瓷层内嵌在基膜中的部分厚度占陶瓷层总厚度的5％、10％、50％、70％、80％或100％以及这些中的任意两者所组成的范围。
当陶瓷层内嵌在基膜中的部分在上述范围内时，有利于较好地利用基膜自身的熔融界面粘结陶瓷颗粒，减少粘结剂的使用，降低隔离膜内阻。
在一些实施方式中，可选地，所述涂层还包括位于所述类勃姆石层的远离所述基膜的表面上的导热层。
所述导热层是一层高导热性的薄膜，如六方-氮化硼(h-BN)，其主要功效是提供均匀的热场环境，避免局部热点的出现，使得锂离子的沉积/溶解均匀化，进而从源头上减少锂枝晶的出现。此外，所述导热层还可以促进无机SEI(固态电解质界面膜，Solid Electrolyte Interface)膜的形成，从而减少锂枝晶的出现。同时，导热层是绝缘体，也不会消耗活性锂。
在一些实施方式中，可选地，所述隔离膜满足下述条件中的至少一个：
(1)所述陶瓷层的厚度为0.5-10μm、可选为2-7μm；
(2)所述基膜的厚度为4-20μm、可选为5-12μm；
(3)所述类勃姆石层的厚度为0.5-10μm、可选为2-7μm；以及
(4)所述导热层的厚度为0.5-2μm、可选为0.5-1μm。
当隔离膜满足上述条件中的一个或多个时，有利于进一步提升隔离膜的安全性能，并降低隔离膜的内阻。
在一些实施方式中，可选地，所述陶瓷层与所述类勃姆石层的厚度之比的比值为0.05-20，可选0.28-3.5。作为示例，所述比例可为5∶1、4∶1、3.5∶1、1∶1、1∶3.5、1∶4或1∶5以及这些中的任意两者所组成的范围。
在一些实施方式中，可选地，所述类勃姆石层与所述导热层的厚度之比的比值为0.25-20，可选2-14。作为示例，上述比例可为0.5∶1、1∶1、2∶1、2∶0.5、7∶1或10∶1以及这些中的任意两者所组成的范围。
当隔离膜中陶瓷层与类勃姆石层或类勃姆石层与导热层的厚度满足上述条件时，有利于进一步提升隔离膜的安全性能，并降低隔离膜的内阻。
在一些实施方式中，可选地，所述陶瓷选自以下元素的氧化物、氮化物、氟化物或含氧酸盐中的一种或多种：Al、Fe、Ti、Co、Zn、Cu、Ni、Mn或Sn；
可选地，所述陶瓷选自Fe的氧化物、Fe的含氧酸盐、Ti的氧化物、Ti的含氧酸盐、Zn的氧化物、NiO、CuO或SnO 2中的一种或多种；
更可选地，所述陶瓷选自Fe 2O 3、FePO 4、TiO 2、ZnO、Li 4Ti 5O 12、NiO、CuO或SnO 2中的一种或多种。
在锂金属电池数次充放电过程中，不可避免地会产生锂枝晶。如果不加控制，锂枝晶最终会接触并刺破隔离膜，导致正负极接触，从而引发安全问题。本申请所述陶瓷颗粒所包含的成分如二氧化硅能够发生嵌锂反应，及时消耗产生的锂枝晶，从而提升相应电池的安全性能。
本申请所述陶瓷颗粒消耗锂枝晶的反应机理可分为合金化反应机制、插层反应机制和氧化还原机制∶
1)合金化反应机制：金属氧化物与锂枝晶发生反应，伴随有金属单质生成，然后生成的金属单质发生进一步的合金化反应生成锂合金，反应方程式为：
A xO y+2yLi ++2ye -→xA+yLi 2O
Figure PCTCN2022112165-appb-000001
以二氧化锡为例，在放电过程中首先生成锡单质和Li 2O，然后锡单质和Li +反应生成Li 4.4Sn化合物。
2)插层反应机制：在充放电过程中Li +只能嵌入材料的层间结构的空隙中，其充放电过程的化学反应式为：
Figure PCTCN2022112165-appb-000002
插层反应机制的代表陶瓷材料主要是SiO 2、TiO 2、钛酸锂等。
3)转化反应机制：金属氧化物与Li +发生氧化还原反应生成金属单质和Li 2O，其化学反应式为：
A xO y+2yLi ++2ye -→xA+yLi 2O
在一些实施方式中，可选地，所述陶瓷为陶瓷颗粒，所述陶瓷颗粒的体积平均粒径Dv50≥100nm，可选为100nm-5μm，更可选为200nm-2μm。
若陶瓷颗粒粒径过大时，则陶瓷颗粒内嵌在基膜中的难度较大，可能发生“掉粉”现象。若陶瓷颗粒粒径过小，则陶瓷颗粒可能堵塞有机微孔材料表面的孔隙，降低了隔离膜的透气度，从而阻断了离子传输通道，不利于降低隔离膜内阻。
在一些实施方式中，可选地，所述类勃姆石层选自勃姆石、氧化铝、氧化锆或氧化镁中的一种或多种。
在一些实施方式中，可选地，所述导热层的导热系数≥20W/(m.K)；
可选地，所述导热层选自氮化硼、氮化钨、碳化硅或氮化铝中的一种或多种。
当隔离膜中的导热层满足上述条件时，有利于进一步提升隔离膜的安全性能，并降低隔离膜的内阻。
在一些实施方式中，可选地，所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯、芳纶、聚对苯二甲酸乙二醇酯、聚四氟乙烯、聚丙烯腈、聚酰亚胺、聚酰胺、聚酯或天然纤维中的一种或多种；
可选地，所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯或聚四氟乙烯中的一种或多种。
本申请所述隔离膜可通过本领域通常使用的方法制备。作为示例，如果使用商用基膜，则本申请所述隔离膜可通过以下方法制备：
1)对隔离膜基膜进行熔融处理，然后经挤出得到基膜A；
2)将陶瓷颗粒均匀分散在步骤1)所得基膜A的一个表面上，得到复合基膜；和
3)依次将类勃姆石颗粒和可选地导热材料均匀涂布在步骤2)所得复合基膜上。
需要说明的是，步骤1)中的熔融处理是指将隔离膜基膜加热至120-250℃，使其达到熔融状态以便可以进行挤出处理。步骤3)中的“依次”是指先涂布类勃姆石层，然后将可选的导热材料涂布在类勃姆石远离陶瓷层的表面上。
在一些实施方式中，可选地，在经过步骤1)中的熔融处理后，所述隔离膜基膜呈热熔状态。
在一些实施方式中，可选地，在步骤1)中，在进行熔融处理后，通过共挤出系统如双螺杆挤出机连续挤出熔融状态的所述隔离膜基膜。
在一些实施方式中，可选地，步骤1)所得基膜A为热熔状态的流延基膜。
在一些实施方式中，可选地，步骤1)还包括在挤出后通过流延冷却辊的步骤。
在一些实施方式中，可选地，步骤1)中所述流延冷却辊的温度为90-25℃。
在一些实施方式中，可选地，步骤2)与所述通过流延冷却辊同步进行；或者
在进行步骤1)后，不晚于10s-1h、可选不晚于1-30min、更可选立即进行步骤2)。
需要说明的是，步骤2)中的术语“同步”意指在步骤1)通过流延冷却辊的同时，步骤2)同步进行，即边成膜边撒粉或喷粉。
在一些实施方式中，可选地，在步骤2)中，可通过在线撒涂或喷涂装置将陶瓷颗粒均匀分散在步骤1)所得基膜A的一个表面上。
在一些实施方式中，可选地，步骤2)还包括通过热复合辊或在烘箱中干燥的步骤。
在一些实施方式中，可选地，在步骤2)中所述热复合辊或烘箱的温度为80-190℃，可选100-180℃。
在一些实施方式中，可选地，在步骤2)中所述热复合辊的压力为5-100Mpa，可选10-50Mpa。
因此，在一些实施方式中，可选地，步骤2)满足以下条件中的一个或多个：
(1)热复合辊的温度为80-190℃，可选100-180℃；
(2)热复合辊的压力为5-100Mpa，可选10-50Mpa。
在一些实施方式中，可选地，在步骤2)中，在通过热复合辊之前，可通过一种或多种以下方法将陶瓷颗粒和步骤1)所得流延基膜A复合：粉末刮涂、喷洒、溶液涂覆或高速粉末喷涂。
在一些实施方式中，可选地，在步骤3)中，可通过凹版涂布法或线棒涂布法涂布类勃姆石颗粒和导热材料。
在一些实施方式中，可选地，所述陶瓷层仅含少量粘结剂(通常为聚合物)。作为示例，所述粘结剂的含量可为0-10wt％，基于所述陶瓷层的总重量计。所述粘结剂可选自以下材料中的一种或多种：聚偏二氟乙烯、聚四氟乙烯、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、聚丙烯酸酯、含氟丙烯酸酯、丁苯橡胶、聚丙烯酸钠、聚甲基丙烯酸、 聚丙烯酰胺、聚乙烯醇、海藻酸钠、羧甲基壳聚糖、羧甲基纤维素钠。
在一些实施方式中，可选地，所述陶瓷层不含粘合剂。
作为示例，如果使用聚烯烃原材料，则可通过以下方法制备本申请所述隔离膜：
1)对包含隔离膜基膜原材料、成孔剂的混合物进行熔融处理，然后经挤出形成基膜A；
2)将陶瓷颗粒均匀分散在基膜A的一个表面上，得到复合基膜；和
3)依次将类勃姆石颗粒和可选地导热材料均匀涂布在步骤2)所得复合基膜上。
在一些实施方式中，可选地，步骤1)中的熔融处理是指将隔离膜基膜加热至120-250℃，使其达到熔融状态以便可以进行挤出处理。步骤3)中的“依次”是指先涂布类勃姆石层，然后将可选的导热材料涂布在类勃姆石远离陶瓷层的表面上。
在一些实施方式中，可选地，步骤1)所述混合物中隔离膜基膜原材料与成孔剂的质量比为0.1-0.7∶1。
在一些实施方式中，可选地，步骤1)所得基膜A为热熔状态的流延基膜。
在一些实施方式中，可选地，步骤1)还包括在挤出后通过流延冷却辊的步骤。
在一些实施方式中，可选地，步骤1)中所述流延冷却辊的温度为90-25℃。
在一些实施方式中，可选地，步骤1)中的成孔剂可选自矿物油、碳酸丙烯酯(即1，2-丙二醇碳酸酯)、碳酸二乙酯或碳酸甲乙酯中的一种或多种。
在一些实施方式中，可选地，步骤2)与所述通过流延冷却辊同步进行；或者
在进行步骤1)后，不晚于10s-1h、可选不晚于1-30min、更可选立即进行步骤2)。
在一些实施方式中，可选地，步骤2)中的术语“同步”意指在步骤1)通过流延冷却辊的同时，步骤2)同步进行，即边成膜边撒粉或喷粉。
在一些实施方式中，可选地，在步骤2)中，可通过在线撒涂或喷涂装置将陶瓷颗粒均匀分散在基膜A的一个表面上。
在一些实施方式中，可选地，在步骤2)中，所述在线撒涂或喷涂装置的热复合速度为0.5-5.0m/min，可选0.5-2.0m/min。
在一些实施方式中，可选地，步骤2)还包括通过热复合辊或在烘箱中干燥的步骤。
在一些实施方式中，可选地，在步骤2)中所述热复合辊或烘箱的温度为80-190℃，可选100-180℃。
在一些实施方式中，可选地，在步骤2)中所述热复合辊的压力为5-100Mpa，可选10-50Mpa。
在一些实施方式中，可选地，在进行步骤2)之后和在进行步骤3)之前，还包括对复合基膜进行拉伸的步骤。
在一些实施方式中，可选地，所述拉伸可以为双向异步拉伸、双向同步拉伸的一种或者多种。
在一些实施方式中，可选地，可按照孔隙率和强度需求对所述基膜进行拉伸。
在一些实施方式中，可选地，在对复合基膜进行拉伸之后，还包括将复合基膜中的成孔剂萃取出来的步骤。
在一些实施方式中，可选地，使用的萃取剂选自二氯甲烷、磷酸三甲酯或磷酸三乙酯中的一种或多种。
在一些实施方式中，可选地，可通过凹版涂布法或线棒涂布法涂布类勃姆石颗粒和导热材料。
在一些实施方式中，可选地，通过收卷系统将步骤3)所得隔离膜进行收卷。
需要说明的是，在本申请中，多种因素如热复合辊和烘箱的温度、通过复合辊的速度、形成流延基膜后涂覆陶瓷颗粒的时间、涂覆量或 陶瓷颗粒粒径等均对陶瓷颗粒的内嵌程度有影响，其中热复合辊和烘箱的温度、涂覆量对内嵌程度的影响较大，其他因素的影响相对较小。
在一些实施方式中，可选地，可通过调节热复合辊和烘箱的温度以及涂覆量来调节陶瓷层在基膜中的内嵌程度。
[二次电池]
本申请的第二方面提供一种二次电池，其包括本申请第一方面所述的隔离膜。通常，除隔离膜以外，二次电池还包括正极极片、负极极片和电解液。
特别地，本申请也可用于锂金属电池，代替传统隔离膜使用。其负极可以为锂金属或锂合金，或者无负极。相应的正极材料如上所述。若为无负极锂金属电池，则正极材料需提供锂源。
二次电池的制备可通过本领域通常使用的方法进行，例如，可将正极极片、负极极片和隔离膜通过卷绕工艺或叠片工艺制成电极组件，然后向电极组件中注入电解液并密封而制得二次电池。
需要说明的是，本申请所述二次电池包括扣式电池。当所述二次电池为扣式电池时，正极极片和负极极片的材料可以相同或不同。此外，可通过本领域技术人员通常使用的方法来制备扣式电池。作为示例，可将正极极片、隔离膜和负极极片组装成电极组件，然后向电极组件中注入电解液并密封而制得扣式电池。
下面分别对二次电池的上述部件进行说明。
[正极极片]
正极极片包括正极集流体以及设置在正极集流体至少一个表面上的正极膜层。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。
在一些实施方式中，所述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材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(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。
在本申请中，正极材料是能可逆地嵌入与脱嵌Li+的化合物。
在一些实施方式中，正极活性材料可采用本领域公知的用于电池的正极活性材料。作为示例，可以列举出Li xMO 2或Li yM 2O 4(其中M为过渡金属，0≤x≤1，0≤y≤2)表示的含锂复合氧化物、尖晶石状的氧化物、层状结构的金属硫族化物、橄榄石结构等。例如，可以列举出LiCoO 2等锂钴氧化物、LiMn 2O 4等锂锰氧化物、LiNiO 2等锂镍氧化物、Li 4/3Ti 5/3O 4等锂钛氧化物、锂锰镍复合氧化物、锂锰镍钴复合氧化物；具有LiMPO 4(M＝Fe、Mn、Ni)等橄榄石型结晶结构的材料等。
在一些实施方式中，可选地，正极活性材料是层状结构或尖晶石状结构的含锂复合氧化物，例如以LiCoO 2、LiMn 2O 4、LiNiO 2、LiNi 1/2Mn 1/2O 2等为代表的锂锰镍复合氧化物，以LiNi 1/3Mn 1/3Co 1/3O 2、LiNi 0.6Mn 0.2Co 0.2O 2等为代表的锂锰镍钴复合氧化物，或LiNi 1-x-y-zCo xAl yMg zO 2(式中，0≤x≤1、0≤y≤0.1、0≤z≤0.1、0≤1-x-y-z≤1)等含锂复合氧化物。此外，上述含锂复合氧化物中的构成元素的一部分，被Ge、Ti、Zr、Mg、Al、Mo、Sn等添加元素所取代的含锂复合氧化物等也包含在本申请的范围内。
除上述正极活性材料以外，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。例如，通过同时使用层状结构的含锂复合氧化物与尖晶石结构的含锂复合氧化物，可以谋求兼顾大容量化及安全性的提高。
在一些实施方式中，正极膜层还可选地包括导电剂。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。
在一些实施方式中，可选地，所述导电剂占正极膜层总重量的0.05-5％，可选为0.5-3％。
在一些实施方式中，正极膜层还可选地包括粘结剂，例如聚偏二氟乙烯、聚四氟乙烯、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、聚环氧乙烷等电池领域中通常使用的粘结剂。
在一些实施方式中，可选地，所述粘结剂占正极膜层总重量的0.1-3.5％，可选为0.5-2.5％。
在一些实施方式中，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。
[负极极片]
负极极片包括负极集流体以及设置在负极集流体至少一个表面上的负极膜层。作为示例，负极集流体具有在其自身厚度方向相对的两个表面，负极膜层设置在负极集流体相对的两个表面中的任意一者或两者上。
在一些实施方式中，所述负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，可以采用铜箔。复合集流体可包括高分子材料基材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。
在本申请中，负极材料是能够嵌入-脱嵌锂金属、锂的化合物。
在一些实施方式中，负极活性材料可采用本领域公知的用于电池的负极活性材料。作为示例，可使用铝、硅、锡等的合金或氧化物、碳材料等各种材料作为负极活性材料。可选地，氧化物可以举出二氧 化钛等，碳材料可以举出石墨、热解碳类、焦炭类、玻璃状碳类、有机高分子化合物的烧成体、中间相碳微珠等。所述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。
在一些实施方式中，负极膜层还可选地包括导电剂。导电剂可选自超导碳、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。
在一些实施方式中，可选地，所述导电剂占负极膜层总重量的0.05-5％，可选为0.5-3％。
在一些实施方式中，负极膜层还可选地包括粘结剂，例如聚偏二氟乙烯、聚四氟乙烯、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、聚环氧乙烷等电池领域中通常使用的粘结剂。
在一些实施方式中，可选地，所述粘结剂占负极膜层总重量的0.1-3.5％，可选为0.5-2.5％。
在一些实施方式中，负极膜层还可选地包括其他助剂，例如增稠剂(如羧甲基纤维素钠(CMC-Na))等。
在一些实施方式中，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。
[电解质]
电解质在正极极片和负极极片之间起到传导离子的作用。本申请对电解质的种类没有具体的限制，可根据需求进行选择。例如，电解质可以是液态的、凝胶态的或全固态的。
在一些实施方式中，所述电解质采用电解液。所述电解液包括电解质盐和溶剂。
在一些实施方式中，使用非水溶剂(有机溶剂)作为非水电解液。 非水溶剂包括碳酸酯类、醚类等。
在一些实施方式中，碳酸酯类包括环状碳酸酯和链状碳酸酯。环状碳酸酯可以列举出碳酸亚乙酯、碳酸亚丙酯、碳酸亚丁酯、γ-丁内酯、硫类酯(乙二醇硫化物)等。链状碳酸酯可以列举出碳酸二甲酯、碳酸二乙酯、碳酸甲乙酯等为代表的低粘度的极性链状碳酸酯、脂肪族支链型碳酸酯类化合物。环状碳酸酯(特别是碳酸乙烯酯)与链状碳酸酯的混合溶剂是特别优选的。
醚类可以列举出二甲醚四甘醇(TEGDME)、乙二醇二甲醚(DME)、1，3-二氧戊烷(DOL)等。
另外，除上述非水溶剂外，还可以采用丙酸甲酯等链状烷基酯类、磷酸三甲酯等链状磷酸三酯；3-甲氧基丙腈等腈类溶剂；以树枝状化合物为代表的具有醚键的支链型化合物等非水溶剂(有机溶剂)。
另外，也可采用氟类溶剂。
作为氟类溶剂，例如，可以列举出H(CF 2) 2OCH 3、C 4F 9OCH 3、H(CF 2) 2OCH 2CH 3、H(CF 2) 2OCH 2CF 3、H(CF 2) 2CH 2O(CF 2) 2H等、或CF 3CHFCF 2OCH 3、CF 3CHFCF 2OCH 2CH 3等直链结构的(全氟烷基)烷基醚，例如2-三氟甲基六氟丙基甲醚、2-三氟甲基六氟丙基乙醚、2-三氟甲基六氟丙基丙醚、3-三氟甲基八氟丁基甲醚、3-三氟甲基八氟丁基乙醚、3-三氟甲基八氟丁基丙醚、4-三氟甲基十氟戊基甲醚、4-三氟甲基十氟戊基乙醚、4-三氟甲基十氟戊基丙醚、5-三氟甲基十二氟己基甲醚、5-三氟甲基十二氟己基乙醚、5-三氟甲基十二氟己基丙醚、6-三氟甲基十四氟庚基甲醚、6-三氟甲基十四氟庚基乙醚、6-三氟甲基十四氟庚基丙醚、7-三氟甲基十六氟辛基甲醚、7-三氟甲基十六氟辛基乙醚、7-三氟甲基十六氟辛基丙醚等。
另外，上述异(全氟烷基)烷基醚与上述直链结构的(全氟烷基)烷基醚也可并用。
作为非水电解液中使用的电解质盐，优选锂的高氯酸盐、有机硼锂盐、含氟化合物的锂盐、锂酰亚胺盐等锂盐。
作为这样的电解质盐的例子，例如，可以列举出LiClO 4、LiPF 6、 LiBF 4、LiAsF 6、LiSbF 6、LiCF 3SO 3、LiCF 3CO 2、LiC 2F 4(SO 3) 2、LiN(C 2F 5SO 2) 2、LiC(CF 3SO 2) 3、LiC nF 2n+1SO 3(n≥2)、LiN(R fOSO 2) 2(式中，R f为氟烷基)等。在这些锂盐中，含氟有机锂盐是特别优选的。含氟有机锂盐，由于阴离子性大且易分离成离子，在非水电解液中易溶解。
电解质锂盐在非水电解液中的浓度，例如为0.3mol/L(摩尔/升)以上，更可选0.7mol/L以上；可选1.7mol/L以下，更可选1.2mol/L以下。当电解质锂盐的浓度过低时，离子传导度过小，过高时，担心未能溶解完全的电解质盐析出。
在一些实施方式中，所述电解液还可选地包括添加剂，本申请不作特别限定。例如添加剂可以包括负极成膜添加剂、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、改善电池高温或低温性能的添加剂等。
[电池模块、电池包和用电装置]
本申请的第三方面提供一种电池模块，包括本申请的第二方面的二次电池。电池模块的制备可采用本领域通常使用的方法。
本申请的第四方面提供一种电池包，包括本申请的第三方面的电池模块。电池包的制备可采用本领域通常使用的方法。
本申请的第五方面提供一种用电装置，包括选自本申请的第二方面的二次电池、本申请的第三方面的电池模块或本申请的第四方面的电池包中的至少一种。
另外，以下适当参照附图对本申请的二次电池、电池模块、电池包和用电装置进行说明。
在一些实施方式中，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质。
在一些实施方式中，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。
本申请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。例如，图2是作为一个示例的方形结构的二次电池5。
在一些实施方式中，参照图3，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封装于所述容纳腔内。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，本领域技术人员可根据具体实际需求进行选择。
在一些实施方式中，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一个或多个，具体数量本领域技术人员可根据电池模块的应用和容量进行选择。
图4是作为一个示例的电池模块3。参照图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。
在一些实施方式中，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为一个或多个，具体数量本领域技术人员可根据电池包的应用和容量进行选择。
图5和图6是作为一个示例的电池包1。参照图5和图6，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。
另外，本申请还提供一种用电装置，所述用电装置包括本申请提 供的二次电池、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用电装置的电源，也可以用作所述用电装置的能量存储单元。所述用电装置可以包括移动设备(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，但不限于此。
作为所述用电装置，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7是作为一个示例的用电装置。该用电装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该用电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。
实施例
以下，说明本申请的实施例。下面描述的实施例是示例性的，仅用于解释本申请，而不能理解为对本申请的限制。实施例中未注明具体技术或条件的，按照本领域内的文献所描述的技术或条件或者按照产品说明书进行。所用试剂或仪器未注明生产厂商者，均为可以通过市购获得的常规产品。除非特别说明，实施例部分中使用的物质质量均以不包含结晶水的质量计。
一、隔离膜
实施例1
1)将聚乙烯(购自Sigma-Aldrich，CAS号9002-88-4)、矿物油(成孔剂)按重量比1∶10均匀混合，然后加热至150℃，形成熔融状态。经过模头共挤出之后，通过80℃流延冷却辊，形成流延基膜A，厚度为7μm；
2)在步骤1)通过流延冷却辊形成流延基膜A的过程中，同 步通过在线喷涂装置，将体积平均粒径Dv50为100nm的ZnO颗粒均匀分散在流延基膜A的一个表面上，然后通过热复合辊将流延基膜A和陶瓷热复合，热复合温度为170℃，压力为10MPa，速度为1.5m/min；
3)通过拉伸系统对复合基膜进行双向同步拉伸；
4)使用二氯甲烷作为萃取剂将基膜中的成孔剂萃取出来，得到半成品复合隔离膜；
5)用线棒涂布方法将氧化铝(氧化铝与粘结剂(聚丙烯酸酯，数均分子量9000)重量比为0.91∶0.04的混合物在去离子水中形成35％固含量的浆料)均匀分散在陶瓷层上，干燥后的涂布厚度为2μm；
6)用线棒涂布方法将氮化硼(氮化硼与粘结剂(聚偏二氟乙烯，PVDF，数均分子量～50万)重量比为0.91∶0.04的混合物在去离子水中形成35％固含量的浆料)均匀分散在氧化铝层上，干燥后的涂布厚度为1μm；和
7)通过收卷系统进行收卷。
除以下条件外，实施例2-22及对比例1-3的制备条件与实施例1类似，具体请参照表1。
其中，实施例7-9中热复合辊的温度/压力分别为110℃/0.8MPa、110℃/5MPa和140℃/7MPa。
二、扣式电池
正负极均使用直径(Φ)为18mm的锂片，锂片厚度为250μm，中间夹层为实施例和对比例所制备的隔离膜。然后滴加适量(保证极片和隔离膜完全浸润即可)的电解液，组装成2430型号扣式电池。所述电解液通过以下方法制得：将碳酸亚乙酯(EC)和碳酸二甲酯(DMC)按照体积比为1∶1混合，然后加入LiPF 6，搅拌均匀，使LiPF6的浓度为1mol/L。
相关参数测试方法
1.陶瓷颗粒的粒径测试
粒度分析Dv50：占总体积50％的颗粒直径大于此值，另有占总体积50％的颗粒直径小于此值，Dv50表示粉体的中值粒度；
颗粒在激光束的照射下，其散射光的角度与颗粒的直径成反比关系，散射光强随角度的增加呈对数规律衰减，散射光的能量分布与颗粒直径的分布直接相关，通过接受和测量散向光的能量分布就可以得出颗粒的粒度分布特征。参考标准为GB/T19077.1-2009粒度分布激光衍射法。
2.扣式电池的恒压测试
测试流程：以1mA/cm 2将扣式电池恒流放电到100mV，静置(rest)10min，再在100mV下恒压保持5天。记录稳定出现200-600mA的峰值大电流的时间作为该电池体系安全正常运行的时间，即为表1中的短路发生时间。
3.陶瓷层内嵌在基膜中的部分厚度占陶瓷层总厚度的百分比测量
使用液氮将隔离膜淬断，得到平整的隔离膜断面，通过ZEISS sigma 300扫描电镜参照标准JY/T010-1996测量陶瓷层的厚度。用陶瓷层内嵌在基膜中的厚度除以陶瓷层的总厚度乘以100％即得所述百分比。
本申请中的其他厚度可参照上述方法测量。
4.隔离膜离子电导率测试
测试流程：制作含隔离膜的叠片对称电池，阳极极片采用常规石墨极片，Cu片作为集流体，电解液同扣式电池电解液。交流阻抗谱测试的频率范围为1MHz～1kHz，振幅为5mV。根据隔离膜电阻R＝ρL/S*n(L，S，n分别为测试中的隔离膜厚度，面积和层数)，可以得到隔离膜的离子电导率(mS/cm)。
Figure PCTCN2022112165-appb-000003
Figure PCTCN2022112165-appb-000004
根据表1结果可知，使用本申请所述隔离膜的二次电池具备较好的安全性能和较高的离子电导率。不囿于任何理论，可能的原因是本申请所述隔离膜可有效消耗锂枝晶，避免枝晶刺透隔离膜造成短路，从而改善了隔离膜的安全性能；同时，较高的离子电导率表明隔离膜的内阻较小，说明本申请的技术方案可同时实现较低的隔离膜内阻。此外，由表1可以看出，通过对陶瓷颗粒的种类以及各层的厚度进行调整，可进一步提高隔离膜的安全性能和降低隔离膜内阻。
需要说明的是，本申请不限定于上述实施方式。上述实施方式仅为示例，在本申请的技术方案范围内具有与技术思想实质相同的构成、发挥相同作用效果的实施方式均包含在本申请的技术范围内。此外，在不脱离本申请主旨的范围内，对实施方式施加本领域技术人员能够想到的各种变形、将实施方式中的一部分构成要素加以组合而构筑的其它方式也包含在本申请的范围内。

Claims (21)

  1. 一种隔离膜，包括基膜和位于所述基膜上的涂层，所述涂层包括部分内嵌在所述基膜中的陶瓷层和位于所述陶瓷层上的类勃姆石层。
  2. 根据权利要求1所述的隔离膜，其中所述陶瓷层内嵌在基膜中的部分占陶瓷层总厚度的5-100％、可选10-100％、更可选50-100％。
  3. 根据权利要求1或2所述的隔离膜，其中所述涂层还包括位于所述类勃姆石层的远离所述基膜的表面上的导热层。
  4. 根据权利要求1至3中任一项所述的隔离膜，其中，所述隔离膜满足下述条件中的至少一个：
    (1)所述陶瓷层的厚度为0.5-10μm、可选为2-7μm；
    (2)所述基膜的厚度为4-20μm、可选为5-12μm；
    (3)所述类勃姆石层的厚度为0.5-10μm、可选为2-7μm；以及
    (4)所述导热层的厚度为0.5-2μm、可选为0.5-1μm。
  5. 根据权利要求1至4中任一项所述的隔离膜，其中
    所述陶瓷选自以下元素的氧化物、氮化物、氟化物或含氧酸盐中的一种或多种：Al、Fe、Ti、Co、Zn、Cu、Ni、Mn或Sn；
    可选地，所述陶瓷选自Fe的氧化物、Fe的含氧酸盐、Ti的氧化物、Ti的含氧酸盐、Zn的氧化物、NiO、CuO或SnO 2中的一种或多种；
    更可选地，所述陶瓷选自Fe 2O 3、FePO 4、TiO 2、ZnO、Li 4Ti 5O 12、NiO、CuO或SnO 2中的一种或多种。
  6. 根据权利要求1至5中任一项所述的隔离膜，其中
    所述陶瓷为陶瓷颗粒，所述陶瓷颗粒的体积平均粒径Dv50≥100nm，可选为100nm-5μm，更可选为200nm-2μm。
  7. 根据权利要求1至6中任一项所述的隔离膜，其中
    所述类勃姆石层选自勃姆石、氧化铝、氧化锆或氧化镁中的一种或多种。
  8. 根据权利要求3至7中任一项所述的隔离膜，其中
    所述导热层的导热系数≥20W/(m.K)；
    可选地，所述导热层选自氮化硼、氮化钨、碳化硅或氮化铝中的一种或多种。
  9. 根据权利要求1至8中任一项所述的隔离膜，其中
    所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯、芳纶、聚对苯二甲酸乙二醇酯、聚四氟乙烯、聚丙烯腈、聚酰亚胺、聚酰胺、聚酯或天然纤维中的一种或多种；
    可选地，所述基膜选自聚乙烯、聚丙烯、聚偏二氟乙烯或聚四氟乙烯中的一种或多种。
  10. 制备根据权利要求1至9中任一项所述的隔离膜的方法，包括以下步骤：
    1)对包含隔离膜基膜原材料、成孔剂的混合物进行熔融处理，然后经挤出形成基膜A；
    2)将陶瓷颗粒均匀分散在基膜A的一个表面上，得到复合基膜；和
    3)依次将类勃姆石颗粒和可选地导热材料均匀涂布在步骤2)所得复合基膜上。
  11. 根据权利要求10所述的方法，其中步骤1)所述混合物中隔离膜基膜原材料与成孔剂的质量比为0.1-0.7∶1。
  12. 根据权利要求10至11中任一项所述的方法，其中步骤1)还包括在挤出后通过流延冷却辊的步骤。
  13. 根据权利要求12所述的方法，其中步骤2)与权利要求12所述通过流延冷却辊同步进行；或者
    在进行步骤1)后，不晚于10s-1h、可选不晚于1-30min、更可选立即进行步骤2)。
  14. 根据权利要求10至13中任一项所述的方法，其中步骤2)还包括通过热复合辊或在烘箱中干燥的步骤。
  15. 根据权利要求14所述的方法，其中步骤2)满足以下条件中 的一个或多个：
    (1)热复合辊的温度为80-190℃，可选100-180℃；
    (2)热复合辊的压力为5-100Mpa，可选10-50Mpa。
  16. 根据权利要求10至15中任一项所述的方法，其中在进行步骤2)之后和在进行步骤3)之前，还包括对复合基膜进行拉伸的步骤。
  17. 根据权利要求16所述的方法，其中在对复合基膜进行拉伸之后，还包括将复合基膜中的成孔剂萃取出来的步骤。
  18. 一种二次电池，包括权利要求1至9中任一项所述的隔离膜或根据权利要求10至17中任一项所述的方法制备的隔离膜。
  19. 一种电池模块，包括权利要求18所述的二次电池。
  20. 一种电池包，包括权利要求18所述的二次电池或权利要求19所述的电池模块中的至少一种。
  21. 一种用电装置，包括选自权利要求18所述的二次电池、权利要求19所述的电池模块或权利要求20所述的电池包中的至少一种。
PCT/CN2022/112165 2022-08-12 2022-08-12 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置 WO2024031652A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2022/112165 WO2024031652A1 (zh) 2022-08-12 2022-08-12 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置
KR1020247002247A KR20240024220A (ko) 2022-08-12 2022-08-12 분리막, 그 제조 방법, 이를 사용한 이차 전지, 전지 모듈, 전지팩 및 전기 장치

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/112165 WO2024031652A1 (zh) 2022-08-12 2022-08-12 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置

Publications (1)

Publication Number Publication Date
WO2024031652A1 true WO2024031652A1 (zh) 2024-02-15

Family

ID=89850422

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/112165 WO2024031652A1 (zh) 2022-08-12 2022-08-12 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置

Country Status (2)

Country Link
KR (1) KR20240024220A (zh)
WO (1) WO2024031652A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160104876A1 (en) * 2013-04-29 2016-04-14 Optodot Corporation Nanoporous composite separators with increased thermal conductivity
CN112864531A (zh) * 2019-11-08 2021-05-28 惠州比亚迪电池有限公司 隔膜、隔膜的制备方法及电池
CN114079124A (zh) * 2020-08-14 2022-02-22 中国科学院上海硅酸盐研究所 有机-无机复合锂离子电池隔膜及其制备方法
CN114142156A (zh) * 2021-12-01 2022-03-04 上海恩捷新材料科技有限公司 一种导热锂离子隔膜及其制备方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160104876A1 (en) * 2013-04-29 2016-04-14 Optodot Corporation Nanoporous composite separators with increased thermal conductivity
CN112864531A (zh) * 2019-11-08 2021-05-28 惠州比亚迪电池有限公司 隔膜、隔膜的制备方法及电池
CN114079124A (zh) * 2020-08-14 2022-02-22 中国科学院上海硅酸盐研究所 有机-无机复合锂离子电池隔膜及其制备方法
CN114142156A (zh) * 2021-12-01 2022-03-04 上海恩捷新材料科技有限公司 一种导热锂离子隔膜及其制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
no. 9002-88-4

Also Published As

Publication number Publication date
KR20240024220A (ko) 2024-02-23

Similar Documents

Publication Publication Date Title
WO2020134780A1 (zh) 一种正极材料及其制备方法和用途
JP6448017B2 (ja) リチウム二次電池
WO2020135766A1 (zh) 正极活性材料、正极极片、电化学储能装置及装置
WO2021217587A1 (zh) 二次电池、其制备方法及含有该二次电池的装置
WO2022140967A1 (zh) 负极极片、电化学装置和电子装置
WO2022077371A1 (zh) 二次电池、其制备方法、及其相关的电池模块、电池包和装置
CA3040031C (en) Battery module for starting a power equipment
WO2023164794A1 (zh) 电化学装置及包含该电化学装置的电子装置
WO2023070992A1 (zh) 电化学装置及包括其的电子装置
WO2020143413A1 (zh) 用于提高电池性能的包括具有支架结构的复合层和保护层的电极以及电池
US20240170652A1 (en) Positive electrode active material, preparation method thereof, and lithium-ion battery, battery module, battery pack, and electric apparatus containing same
CN108511680B (zh) 正极片及其制备方法及储能装置
US20230307790A1 (en) Separator, preparation method therefor and related secondary battery, battery module, battery pack and device
EP4358215A1 (en) Electrode pole piece and preparation method therefor, secondary battery, battery module, and battery pack
WO2023245837A1 (zh) 隔离膜、其制备方法及其相关的二次电池和用电装置
WO2024031652A1 (zh) 隔离膜、其制备方法及使用其的二次电池、电池模块、电池包和用电装置
EP4102636A1 (en) Separator film, secondary battery containing same, related battery module thereof, battery pack and device
WO2024011404A1 (zh) 隔离膜及使用其的二次电池、电池模块、电池包和用电装置
JP6607388B2 (ja) リチウムイオン二次電池用正極及びその製造方法
WO2024060176A1 (zh) 复合集流体及其制作方法、电极片、二次电池和用电装置
WO2024065715A1 (zh) 隔离膜、二次电池和用电装置
WO2023245597A1 (zh) 一种正极活性材料、二次电池、电池模块、电池包和用电装置
WO2024082290A1 (zh) 碳化钛及其用途、制法、二次电池和用电装置
WO2023216052A1 (zh) 一种电解液、二次电池、电池模块、电池包和用电装置
WO2024000095A1 (zh) 负极极片、二次电池、电池模组、电池包及用电装置

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 20247002247

Country of ref document: KR

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 2022954611

Country of ref document: EP

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22954611

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2022954611

Country of ref document: EP

Effective date: 20240319