CN114171849B - Composite diaphragm with core-shell structure and preparation method thereof - Google Patents
Composite diaphragm with core-shell structure and preparation method thereof Download PDFInfo
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- 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
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- 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
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- 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
- H01M50/411—Organic material
- H01M50/414—Synthetic resins, e.g. thermoplastics or thermosetting resins
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- 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
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- 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
Abstract
A composite diaphragm with a core-shell structure and a preparation method thereof. The invention belongs to the field of lithium ion battery diaphragms. The invention aims to solve the technical problems of poor cycle and rate performance, low capability of inhibiting growth of lithium dendrite and poor thermal stability of a lithium battery caused by insufficient binding force, large bulk resistance and low composite efficiency of the traditional composite diaphragm directly blending ceramic filler and polyvinylidene fluoride. The core-shell structure composite diaphragm is prepared from ceramic filler and a polymer substrate, wherein the ceramic filler is uniformly dispersed in the polymer substrate, and the ceramic filler is a core-shell structure formed by a ceramic core and a polymer shell. According to the invention, the polymer is coated on the outer layer of the inorganic ceramic particles, the core-shell structural unit which is uniformly coated is synthesized by self-assembly, and then the core-shell structural unit is added into the polymer matrix to prepare the composite diaphragm with the core-shell structure, so that the diaphragm with high mechanical strength, high wettability and good interface bonding can be realized, and lithium dendrite can be effectively inhibited.
Description
Technical Field
The invention belongs to the field of lithium ion battery diaphragms, and particularly relates to a core-shell structure composite diaphragm and a preparation method thereof.
Background
The energy is a perpetual topic related to the development of human society, and the key to realizing the development of sustainable energy is to research and develop novel energy so as to replace traditional energy based on petrochemical industry. The lithium ion battery is a focus of research in the energy field due to higher mass/volume capacity, power density, longer cycle life and lower self-discharge efficiency, and has important applications in various fields, such as electric automobiles, consumer electronic products, standby power supply, wind energy, solar energy storage and the like.
A lithium ion battery is a rechargeable battery that charges and discharges and stores energy by lithium ions moving back and forth between a positive electrode and a negative electrode. A separator made of polyethylene or polypropylene is generally arranged between the anode material and the cathode material of the existing commercial lithium ion battery, and the separator is soaked in an alkyl organic carbonate solution containing lithium salt. The diaphragm is used for providing a framework and a channel for lithium ions to move between the positive electrode and the negative electrode and blocking conduction of electrons between the positive electrode and the negative electrode. Commercial positive electrode materials mainly comprise transition metal oxides and phosphoric acid compounds (LiCoO) 2 ,LiMn 2 O 4 ,LiCo x Mn y Ni 1-x-y O 2 ,LiFePO 4 ) The negative electrode material is mainly graphite. The separator material is one of the key components of electrochemical storage power sources, and an ideal lithium ion battery separator should have high liquid absorption, ion conductivity, thermal stability, cycle life and low cost. The polyolefin separator widely applied in the industry cannot well meet the requirements of the lithium battery on high safety, high stability and high energy density, and the flammability and poor thermal stability of the polyolefin separator lead to easy thermal shrinkage of the separator when the battery is in operation, thereby causing short circuit faults and severely limiting the safe application of the battery. In addition, polyolefin separators are poor in liquid absorption, often exhibit a solid-liquid separation state in an electrolyte, and form an interface with an electrode with poor compatibility, thereby forming an unstable Solid Electrolyte (SEI) and thus deteriorating the stability of lithium negative electrode cycle. The SEI phase is easily broken under the action of stress to expose a new lithium surface, so that continuous consumption and degradation of lithium metal are caused, uneven lithium deposition is formed to cause dendrite growth, and finally, a diaphragm is pierced to cause potential safety hazard.
To improve the potential safety hazards presented by commercial separators, a number of researchers have developed a number of high performance lithium battery separator materials by adding ceramic particles to improve the structure or material composition of the separator. However, the commercial polyolefin separator prepared by the dry method and the wet method is difficult to functionalize, and the ceramic particles coated in the commercial separator can cause various problems such as pore blocking, reduced liquid absorption performance, reduced capability of inhibiting lithium dendrites and the like. It has been found by researchers that polyvinylidene fluoride (PVDF) as a binder applied to commercial membrane surfaces can solve the above problems, and is therefore of great interest in the field of membrane research. However, such composite membranes have limitations in themselves: the mechanical performance is low, the functionalization does not realize a molecular level, and the technical problems of insufficient binding force, increased thickness and bulk resistance, composite efficiency caused by random composite and the like exist between the ceramic and the polymer interface, so that the development of the diaphragm with excellent comprehensive performance is particularly important.
Disclosure of Invention
The invention provides a core-shell structure composite diaphragm and a preparation method thereof, which are used for solving the technical problems of poor cycle and rate performance, low capability of inhibiting lithium dendrite growth and poor thermal stability of a lithium battery caused by insufficient binding force, large bulk resistance and low composite efficiency of the existing composite diaphragm which directly blends ceramic filler and polyvinylidene fluoride.
The composite diaphragm with the core-shell structure is prepared from ceramic filler and a polymer substrate, wherein the ceramic filler is of a core-shell structure and is uniformly dispersed in the polymer substrate, and the ceramic filler consists of a ceramic core and a polymer shell.
Further defined, the polymer substrate is one or more of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trifluoroethylene, polyvinylidene fluoride-chlorotrifluoroethylene, polymethyl methacrylate, polyimide and polyacrylonitrile.
Further limited, the mass fraction of the ceramic filler in the core-shell structure composite diaphragm is 5% -15%.
Further defined, the ceramic core is one or more of alumina, silica, zirconia, boron nitride, glass fiber, and layered silicate mineral.
Further defined, the ceramic core has a particle size of 20nm to 200nm.
Further defined, the polymer shell is one or more of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polymethyl methacrylate and polyimide.
Further defined, the mass ratio of the polymer shell to the ceramic core is (1.5-3): 1.
Further defined, the polymer shell thickness is from 4nm to 5nm.
The preparation method of the composite membrane with the core-shell structure comprises the following steps:
step 1: dispersing the ceramic core material in deionized water, magnetically stirring at normal temperature until the ceramic core material is uniformly dispersed, adding a cross-linking agent, magnetically stirring until the ceramic core material is uniformly dispersed, centrifuging, and drying to obtain modified ceramic powder;
step 2: dispersing the modified ceramic powder obtained in the step 1 into an organic solvent, then adding a polymer shell material, stirring at normal temperature until the powder is uniformly dispersed, centrifuging, drying and ball milling to obtain a core-shell structure ceramic filler;
step 3: dissolving a polymer substrate material in acetone, magnetically stirring at 50-70 ℃ until a transparent colloidal solution is obtained, then magnetically stirring at room temperature for 0.5-1 h, cooling to room temperature, adding the core-shell structure ceramic filler obtained in the step 2, magnetically stirring for 6-12 h, and obtaining a mixed solution;
step 4: and (3) coating the mixed solution obtained in the step (3) to obtain the composite membrane with the core-shell structure.
Further defined, the mass ratio of the ceramic core material to deionized water in step 1 is 1: (20-50).
Further defined is that the mass ratio of the ceramic core material to the cross-linking agent in step 1 is (2-20): 1.
Further defined, the cross-linking agent in step 1 is one of polyacrylonitrile, cellulose, citric acid, KH550, KH560, KH 570.
Further defined, the organic solvent in the step 2 is one or more of N-N dimethylformamide, N-N methylpyrrolidone and N-N dimethylacetamide.
Further defined, the mass ratio of the modified ceramic powder to the organic solvent in step 2 is 1: (10-30).
Further defined, the mass ratio of the polymer base material to acetone in step 3 is 1: (5-15).
Further limited, the centrifugal rotational speeds in the step 1-2 are 8000 r/min-12000 r/min.
Further limited, the rotational speed of the magnetic stirring in the step 1-3 is 500 r/min-1500 r/min.
Further defined, the coating in step 4 is in particular a knife coating.
Compared with the prior art, the invention has the remarkable effects that:
according to the invention, the polymer is coated on the outer layer of the inorganic ceramic particles, the core-shell structural unit which is uniformly coated is synthesized by self-assembly, and then the core-shell structural unit is added into the polymer matrix to prepare the composite diaphragm with the core-shell structure, so that the diaphragm with high mechanical strength, high wettability and good interface bonding can be realized, and lithium dendrite can be effectively inhibited. The core-shell composite diaphragm with consistent appearance, high mechanical strength, high thermal stability and controllable aperture and porosity is prepared by the method, and the application requirements of the diaphragm in the field of lithium ion batteries and the field of energy sources can be met, and the method has the following specific advantages:
1. the invention provides a composite diaphragm with a core-shell structure, which can ensure the stability of the diaphragm in the circulating process of a lithium ion battery at normal temperature and high temperature, and ceramic particles in the composite diaphragm cannot be influenced by ion transmission to cause displacement or scattering, so that the composite diaphragm with a stable structure is formed.
2. The composite diaphragm with the core-shell structure ensures the original wettability of the diaphragm and improves the thermal stability and mechanical strength of the diaphragm.
3. The invention provides a preparation method of a composite diaphragm with a core-shell structure, which is simple and easy to realize, and can be directly matched with an emerging improvement scheme of electrolyte and an electrode.
4. The composite diaphragm has the advantages of consistent appearance, high mechanical strength, high thermal stability and controllable porosity. The lithium iron phosphate positive electrode lithium ion battery has good application effect in the lithium ion battery, the discharge capacity of the lithium iron phosphate positive electrode lithium ion battery is 140mAh/g after 600 circles of circulation at 1C, in addition, the discharge capacity of the lithium iron phosphate positive electrode lithium ion battery reaches 155mAh/g after 500 circles of circulation at 1C under the high temperature or special environment, the coulomb efficiency is as high as 99.16%, and the discharge capacity is obviously improved compared with the capacity retention rate of commercial batteries and batteries in research at home and abroad.
5. The composite diaphragm of the invention effectively improves the thermal stability, the thermal expansion rate at 150 ℃ is 2%, and the high temperature performance of the battery is ensured.
Drawings
FIG. 1 is a transmission electron microscope morphology diagram of the core-shell structure ceramic filler obtained in the step 2 of the example 2;
FIG. 2 is a high resolution transmission electron microscope morphology of the core-shell structured ceramic filler obtained in step 2 of example 2;
FIG. 3 is a graph depicting the thermal stability of the diaphragms of the examples and comparative examples of the present invention;
FIG. 4 is a graph showing the mechanical strength characterization of the diaphragms of the examples and comparative examples of the present invention;
FIG. 5 is a graph showing the electrolyte absorption rate of separators of examples and comparative examples according to the present invention;
FIG. 6 is a graph of the wettability characterization of the separator of the examples and comparative examples of the present invention;
FIG. 7 is a graph depicting the cycling performance at 1C of a lithium battery employing the separators of examples 1-3 at 80 ℃;
FIG. 8 is a graph depicting the cycling performance of lithium batteries at 1C for different separators at 25 ℃;
FIG. 9 is a graph depicting the rate performance of lithium batteries with different separators at 25 ℃;
FIG. 10 is a graph depicting the cycling performance of lithium batteries at 1C for different separators at 80 ℃;
FIG. 11 is a graph depicting coulombic efficiency at 1C for lithium batteries with different separators at 80 ℃;
FIG. 12 is a graph depicting the rate performance of lithium batteries with different separators at 80deg.C;
in fig. 3-12: celgard 2500-commercial polyolefin separator and PVDF-comparative example1 pure polyvinylidene fluoride, al 2 O 3 PVDF-directly doped alumina-polyvinylidene fluoride composite membrane of comparative example 2, APCS-5/PVDF-core-shell structured composite membrane of inventive example 1, APCS-10/PVDF-core-shell structured composite membrane of inventive example 2, APCS-15/PVDF-core-shell structured composite membrane of inventive example 3.
Detailed Description
The core-shell structure composite diaphragm of the embodiment 1 is prepared from ceramic filler and a polymer substrate, wherein the ceramic filler is uniformly dispersed in the polymer substrate, the ceramic filler is a core-shell structure formed by a ceramic core and a polymer shell, the polymer substrate is polyvinylidene fluoride, the mass fraction of the ceramic filler in the core-shell structure composite diaphragm is 5%, the ceramic core is aluminum oxide, the particle size of the ceramic core is 20nm, the polymer shell is polyvinylidene fluoride, and the mass ratio of the polymer shell to the ceramic core is 2:1;
the preparation method of the core-shell structure composite membrane of the preparation example 1 comprises the following steps:
step 1: dispersing aluminum oxide in deionized water, magnetically stirring at normal temperature and 1000r/min for 6h, adding KH550, magnetically stirring until the aluminum oxide is uniformly dispersed, centrifuging at 10000r/min, and drying to obtain modified ceramic powder; the mass ratio of the ceramic core material to deionized water is 1:30, wherein the mass ratio of the alumina to KH550 is 5:1;
step 2: dispersing the modified ceramic powder obtained in the step 1 into N-N dimethylformamide, then adding polyvinylidene fluoride, stirring at normal temperature for 12h, centrifuging at 10000r/min, drying, and ball milling to obtain a core-shell structure ceramic filler; the mass ratio of the modified ceramic powder to the N-N dimethylformamide is 1:15; the mass ratio of the modified ceramic powder to the polyvinylidene fluoride is 2:1;
step 3: dissolving polyvinylidene fluoride in acetone, magnetically stirring at 55 ℃ and 1000r/min for 30min to obtain a transparent colloidal solution, then magnetically stirring at room temperature and 1000r/min for 1h, cooling to room temperature, adding the core-shell structure ceramic filler obtained in the step 2, and magnetically stirring at 1000r/min for 12h to obtain a mixed solution; the mass ratio of the polyvinylidene fluoride to the acetone is 1:10;
step 4: and (3) carrying out knife coating on the mixed solution obtained in the step (3) to obtain the core-shell structure composite membrane with the thickness of 25 mu m.
Example 2, this example differs from example 1 in that: the mass fraction of the ceramic filler in the core-shell structure composite diaphragm is 10%. Other steps and parameters were the same as in example 1.
Example 3, this example differs from example 1 in that: the mass fraction of the ceramic filler in the core-shell structure composite diaphragm is 15%. Other steps and parameters were the same as in example 1.
Comparative example 1: the embodiment provides a polyvinylidene fluoride diaphragm, and the preparation method thereof is as follows:
step 1, dissolving polyvinylidene fluoride in acetone, magnetically stirring for 30min at 55 ℃ and 1000r/min to obtain a transparent colloidal solution, and magnetically stirring for 1h at room temperature and 1000 r/min; the mass ratio of the polyvinylidene fluoride to the acetone is 1:10;
and 2, placing the solution obtained in the step 1 on a coating machine, and setting a scraper to 400 mu m to obtain the pure polyvinylidene fluoride diaphragm with the thickness of 25 mu m.
Comparative example 2: the embodiment provides an alumina-polyvinylidene fluoride composite diaphragm, and the preparation method thereof is as follows:
step 1, dissolving polyvinylidene fluoride in acetone, magnetically stirring for 30min at 55 ℃ and 1000r/min to obtain a transparent colloidal solution, and magnetically stirring for 1h at room temperature and 1000 r/min; the mass ratio of the polyvinylidene fluoride to the acetone is 1:10;
step 2, directly adding aluminum oxide into the transparent colloidal solution in the step 1, and magnetically stirring for 6 hours at 1000r/min to obtain a mixed solution; the mass ratio of the polyvinylidene fluoride to the aluminum oxide is 9:1, a step of;
and 3, placing the mixed solution obtained in the step 2 on a coating machine, and setting a scraper to 400 mu m to obtain the directly doped aluminum oxide-polyvinylidene fluoride composite diaphragm with the thickness of 25 mu m.
Detection test: the core-shell structured composite separator of examples 1-3, as well as commercial polyolefin separator (Celgard 2500), the pure polyvinylidene fluoride separator of comparative example 1, and the directly doped alumina-polyvinylidene fluoride composite separator of comparative example 2 were assembled in lithium ion battery (CR 2025) of lithium iron phosphate positive electrode/lithium metal negative electrode, and then performance test was performed on the assembled lithium ion battery, specifically as follows:
1. electrochemical performance test of normal temperature/high temperature battery:
(1) the electrolyte at normal temperature adopts LiPF of 1mol/L 6 Dissolving in a mixed solvent consisting of ethylene carbonate, diethyl carbonate and ethylmethyl carbonate, wherein the volume ratio of the ethylene carbonate to the diethyl carbonate to the ethylmethyl carbonate is 1:1:1;
(2) the electrolyte at high temperature adopts LiPF of 1mol/L 6 Dissolved in ethylene carbonate, diethyl carbonate, propylene carbonate, diphenyl sulfone, vinylene carbonate, succinonitrile, wherein ethylene carbonate: diethyl carbonate: propylene carbonate: diphenyl sulfone: vinylene carbonate: the volume ratio of succinonitrile is 1:1:1:1:0.1:0.1;
(3) the battery assembling process comprises the following steps: assembled battery with CR2025 button cell, the electrolyte is adopted as electrolyte, and the anode is lithium iron phosphate (LiFePO) 4 ) Wherein the positive electrode material is LiFePO with the mass ratio of 8:1:1 4 The cathode is lithium metal.
(4) Detecting parameters: after the battery is assembled, the battery is placed on a new battery testing system for testing, and the voltage range of charge and discharge is 2.5V-4.2V.
2. Mechanical property test: the mechanical strength of the separator was measured using a tensile tester. The diaphragm was cut into 2cm×6cm rectangular sheets, clamped in a tensile tester, and the cross-sectional area of the diaphragm and the thickness of the diaphragm were input to form a tensile test curve, to obtain the mechanical strength of the diaphragm.
3. Thermal stability test: the thermal imaging properties of the diaphragm were measured using a fourier thermal imaging tester. The separator was cut into circular sheets of 16mm diameter with a substrate of 5cm by 5cm copper foil. When the temperature rises, heat is transferred to the separator through the copper foil. Infrared light of 7.5-13 mu m is detected, and an infrared image with the frequency of 7.5Hz is formed. Imaging was performed using a noise equivalent temperature difference mode and a 17 μm lens.
4. Electrolyte absorption rate test: the mass of the separator was weighed, then the separator was immersed in the electrolyte for 60 minutes, and the mass was weighed once every 5 minutes, and the electrolyte absorption rate was obtained from (mass after immersion-initial mass)/initial mass.
5. Wettability test: contact angle testing may be accomplished by a contact angle tester, where an electrolyte is dropped onto the separator, through which the degree of wetting of the separator may be observed.
The test results are shown in FIGS. 1-12 and Table 1:
as can be seen from fig. 1-2, the alumina is coated with polyvinylidene fluoride, and the thickness of the polyvinylidene fluoride coating is about 4nm to 5nm.
As can be seen from fig. 3, as the temperature increases, the core-shell structure composite separator of the present invention has the smallest thermal shrinkage, which means that the thermal stability is the highest, and the good cycle of the battery at high temperature is ensured.
As can be seen from fig. 4, the mechanical strength of the core-shell structure composite membrane of the present invention is maximum, 27Mpa, which ensures the inhibition ability of lithium dendrite and the stability of the membrane during the operation of the battery.
As can be seen from fig. 5, the electrolyte of the composite membrane with the core-shell structure has the highest absorption of 240%, ensures the property of storing the electrolyte by the membrane, and can further improve the rate capability of the lithium ion battery.
As can be seen from fig. 6, the contact angle of the composite membrane with the core-shell structure is the smallest (8 °), which ensures the property of the membrane for storing electrolyte, and can further improve the rate capability of the lithium ion battery.
From fig. 7-12, it can be seen that the lithium ion battery with the core-shell structure composite membrane has more excellent cycle performance and rate capability at normal temperature and high temperature.
Table 1 battery performance test data
Claims (8)
1. The preparation method of the composite membrane with the core-shell structure is characterized in that the composite membrane with the core-shell structure is prepared from ceramic filler and a polymer substrate, wherein the ceramic filler is of a core-shell structure and is uniformly dispersed in the polymer substrate, and the ceramic filler is composed of a ceramic core and a polymer shell; wherein the polymer substrate is one or more of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trifluoroethylene and polyvinylidene fluoride-chlorotrifluoroethylene; the polymer shell is one or more of polyvinylidene fluoride and polyvinylidene fluoride-hexafluoropropylene; the mass fraction of the ceramic filler in the core-shell structure composite diaphragm is 10% -15%; the thickness of the polymer shell layer is 4 nm-5 nm;
the preparation method comprises the following steps:
step 1: dispersing the ceramic core material in deionized water, magnetically stirring at normal temperature until the ceramic core material is uniformly dispersed, adding a cross-linking agent, magnetically stirring until the ceramic core material is uniformly dispersed, centrifuging, and drying to obtain modified ceramic powder;
step 2: dispersing the modified ceramic powder obtained in the step 1 into an organic solvent, then adding a polymer shell material, stirring at normal temperature until the powder is uniformly dispersed, centrifuging, drying and ball milling to obtain a core-shell structure ceramic filler;
step 3: dissolving a polymer substrate material in acetone, magnetically stirring at 50-70 ℃ until a transparent colloidal solution is obtained, then magnetically stirring at room temperature for 0.5-1 h, cooling to room temperature, adding the core-shell structure ceramic filler obtained in the step 2, magnetically stirring for 6-12 h, and obtaining a mixed solution;
step 4: and (3) coating the mixed solution obtained in the step (3) to obtain the composite membrane with the core-shell structure.
2. The preparation method of the core-shell structure composite membrane according to claim 1, wherein the ceramic core is one or more of alumina, silica, zirconium dioxide, boron nitride, glass fiber and layered silicate mineral, and the particle size of the ceramic core is 20 nm-200 nm.
3. The method for preparing a composite membrane with a core-shell structure according to claim 1, wherein the mass ratio of the polymer shell to the ceramic core is (1.5-3): 1.
4. The method for preparing the composite membrane with the core-shell structure according to claim 1, wherein the mass ratio of the ceramic core material to deionized water in the step 1 is 1: and (20-50), wherein the mass ratio of the ceramic core material to the cross-linking agent in the step 1 is (2-20) 1, and the cross-linking agent in the step 1 is one of polyacrylonitrile, cellulose, citric acid, KH550, KH560 and KH 570.
5. The preparation method of the core-shell structure composite membrane according to claim 1, wherein the organic solvent in the step 2 is one or more of N-N dimethylformamide, N-N methylpyrrolidone and N-N dimethylacetamide, and the mass ratio of the modified ceramic powder to the organic solvent in the step 2 is 1: (10-30).
6. The method for preparing a composite membrane with a core-shell structure according to claim 1, wherein the mass ratio of the polymer base material to the acetone in the step 3 is 1: (5-15).
7. The preparation method of the composite membrane with the core-shell structure, which is characterized in that the centrifugal rotating speed in the step 1-2 is 8000 r/min-12000 r/min, and the magnetic stirring rotating speed in the step 1-3 is 500 r/min-1500 r/min.
8. The method for preparing a composite membrane with a core-shell structure according to claim 1, wherein the coating in the step 4 is in particular knife coating.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015028842A (en) * | 2013-06-28 | 2015-02-12 | 日本ゼオン株式会社 | Adhesive agent for lithium ion secondary batteries, lithium ion secondary battery separator, and lithium ion secondary battery |
| JP2015041576A (en) * | 2013-08-23 | 2015-03-02 | 日本ゼオン株式会社 | Separator for lithium ion secondary battery, and lithium ion secondary battery |
| KR20170025159A (en) * | 2015-08-27 | 2017-03-08 | 주식회사 엘지화학 | Separator having an embossing layer and Lithium secondary battery comprising the same |
| CN110854339A (en) * | 2018-08-20 | 2020-02-28 | 广东美联隔膜有限公司 | In-situ composite ceramic diaphragm with core-shell structure and preparation method and application thereof |
| WO2020091537A1 (en) * | 2018-11-01 | 2020-05-07 | 주식회사 엘지화학 | Separator and electrochemical device comprising same |
| WO2020224319A1 (en) * | 2019-05-08 | 2020-11-12 | 宁德新能源科技有限公司 | Separator and electrochemical device |
| CN113363671A (en) * | 2021-06-30 | 2021-09-07 | 宁德新能源科技有限公司 | Electrochemical device and electronic device |
-
2021
- 2021-11-18 CN CN202111369168.6A patent/CN114171849B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015028842A (en) * | 2013-06-28 | 2015-02-12 | 日本ゼオン株式会社 | Adhesive agent for lithium ion secondary batteries, lithium ion secondary battery separator, and lithium ion secondary battery |
| JP2015041576A (en) * | 2013-08-23 | 2015-03-02 | 日本ゼオン株式会社 | Separator for lithium ion secondary battery, and lithium ion secondary battery |
| KR20170025159A (en) * | 2015-08-27 | 2017-03-08 | 주식회사 엘지화학 | Separator having an embossing layer and Lithium secondary battery comprising the same |
| CN110854339A (en) * | 2018-08-20 | 2020-02-28 | 广东美联隔膜有限公司 | In-situ composite ceramic diaphragm with core-shell structure and preparation method and application thereof |
| WO2020091537A1 (en) * | 2018-11-01 | 2020-05-07 | 주식회사 엘지화학 | Separator and electrochemical device comprising same |
| WO2020224319A1 (en) * | 2019-05-08 | 2020-11-12 | 宁德新能源科技有限公司 | Separator and electrochemical device |
| CN113363671A (en) * | 2021-06-30 | 2021-09-07 | 宁德新能源科技有限公司 | Electrochemical device and electronic device |
Non-Patent Citations (1)
| Title |
|---|
| "聚偏氟乙烯电纺纳米纤维电池隔膜研究进展";李好义 等;《化工新型材料》;第49卷(第7期);第6-9+14页 * |
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