CN115483500A - High-circulation-rate diaphragm and preparation method thereof - Google Patents

High-circulation-rate diaphragm and preparation method thereof Download PDF

Info

Publication number
CN115483500A
CN115483500A CN202211150890.5A CN202211150890A CN115483500A CN 115483500 A CN115483500 A CN 115483500A CN 202211150890 A CN202211150890 A CN 202211150890A CN 115483500 A CN115483500 A CN 115483500A
Authority
CN
China
Prior art keywords
stirring
coating
blending
time
diaphragm
Prior art date
Legal status (The legal status 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 status listed.)
Pending
Application number
CN202211150890.5A
Other languages
Chinese (zh)
Inventor
袁海朝
徐锋
李威
苏碧海
田海龙
王建华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hebei Gellec New Energy Material Science and Technoloy Co Ltd
Original Assignee
Hebei Gellec New Energy Material Science and Technoloy Co Ltd
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 Hebei Gellec New Energy Material Science and Technoloy Co Ltd filed Critical Hebei Gellec New Energy Material Science and Technoloy Co Ltd
Priority to CN202211150890.5A priority Critical patent/CN115483500A/en
Publication of CN115483500A publication Critical patent/CN115483500A/en
Pending legal-status Critical Current

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
    • H01M50/403—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
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • 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
    • 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
    • H01M50/417—Polyolefins
    • 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
    • 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
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • 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
    • H01M50/497—Ionic conductivity
    • 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

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Ceramic Engineering (AREA)
  • Cell Separators (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)

Abstract

The invention discloses a high-circulation-rate diaphragm and a preparation method thereof, wherein the preparation method comprises the following steps: step 1, firstly stirring and blending a dispersing agent and pure water for the first time, then adding alumina powder for the second time, stirring and blending to obtain a mixed solution, simultaneously carrying out ultrasonic treatment in the process of stirring and blending for the second time, adding isopropanol, CMC, PMMA and a wetting agent into the mixed solution after stirring for the second time, and carrying out vacuum oscillation, stirring and blending to prepare a coating slurry; step 2, coating the coating slurry obtained in the step 1 on a base film to obtain a coating film; step 3, drying the coating film obtained in the step 2 to obtain a high-circulation-rate diaphragm; according to the invention, PMMA is introduced to improve the binding power of the diaphragm coating and the cycle rate of the battery, and in addition, the aluminum oxide and the PMMA cooperate to improve the ionic conductivity of the diaphragm.

Description

High-circulation-rate diaphragm and preparation method thereof
Technical Field
The invention belongs to the technical field of battery diaphragms, and particularly relates to a high-cycle-rate diaphragm and a preparation method thereof.
Background
With the increasing environmental problems, more and more new energy projects are concerned by the countries and the society, wherein electric vehicles are more favored, the safety, the cruising ability and the like of lithium ion batteries as power sources of the electric vehicles are important in scientific research, the charging and using times of the lithium ion batteries and the utilization rate of the batteries are more important for people to pay attention to modern people living in a fast pace, and lithium battery diaphragms play an important role.
The mainstream products in the market comprise a PDVF (spray coating), a ceramic coating diaphragm and a PVDF ceramic composite diaphragm, wherein the PVDF coating mainly provides interface adhesion and increases the hardness of a battery cell, the ceramic coating mainly provides good safety performance, and a single PVDF or ceramic coating cannot provide the two functions at the same time. Although the composite coating can bring two functions at the same time, the composite coating has the problems of thicker thickness, larger ventilation and the like, and if the diaphragm is larger in ventilation, the hole blocking phenomenon can occur, so that the shuttling of lithium ions is reduced, and the cycle life of the battery is influenced. In addition, the liquid absorption of the composite coating is low, which results in insufficient electrolyte reserve in the battery system, resulting in an increase in interface resistance.
Based on the above, the invention introduces PMMA which is commonly called organic glass to improve the coating adhesion of the diaphragm and the cycle rate of the battery.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of a high-cycle-rate diaphragm
The invention also aims to provide the high-cycle-rate diaphragm obtained by the preparation method.
The purpose of the invention is realized by the following technical scheme.
A preparation method of a high-cycle-rate diaphragm comprises the following steps:
step 1, firstly stirring and blending a dispersing agent and pure water for the first time, then adding alumina powder for the second time, stirring and blending to obtain a mixed solution, simultaneously carrying out ultrasonic treatment in the process of stirring and blending for the second time, adding isopropanol, CMC, PMMA and a wetting agent into the mixed solution after stirring for the second time, and carrying out vacuum oscillation, stirring and blending to prepare a coating slurry; wherein the mass parts of PMMA, alumina, pure water, wetting agent, dispersing agent, isopropanol and CMC are (5-18): (20-30): (51.5-70.9): (0.03-0.09): (0.1-0.2): (3-6): (2.5-7).
And 2, coating the coating slurry obtained in the step 1 on a PE film to obtain a coating film.
And 3, drying the coating film obtained in the step 2 to obtain the high-circulation-rate diaphragm.
In the above technical solution, in the step 1, the dispersant is silicate, and can uniformly disperse inorganic particles that are difficult to dissolve in liquid, and at the same time, can prevent the particles from settling and coagulating, so as to form the amphiphilic agent required for stabilizing the suspension.
In the above technical solution, in the step 1, the wetting agent is sodium hexametaphosphate, and mainly functions to reduce surface tension and enhance slurry fluidity.
In the technical scheme, in the step 1, the rotation speed of the primary stirring and blending is 2000-3100r/min, the revolution speed is 20-40r/min, and the stirring time is 5-45min.
In the technical scheme, in the step 1, the rotation speed of the secondary stirring and blending is 2000-3100r/min, the revolution speed is 20-50r/min, and the stirring time is 10-30min.
In the above technical solution, in the step 1, the ultrasonic frequency of the ultrasound is 20-50KHZ
In the technical scheme, in the step 1, the rotation speed of the vacuum oscillation, stirring and blending is 1000-3000r/min, the revolution speed is 20-40r/min, the ultrasonic oscillation frequency is 5-60kHz, and the stirring time is 15-30min.
In the above technical solution, preferably, in the step 1, a planetary stirring device is used for stirring and blending.
In the above technical solution, in the step 2, the coating is single-side coating.
In the above technical scheme, in the step 2, the coating speed is 30-50m/min.
In the above technical solution, in the step 2, the thickness of the coating layer is 2-4 μm.
In the above technical scheme, in the step 3, the drying is performed by drawing the dried product into a drying device through a drawing roller.
In the above technical scheme, in the step 3, the drying temperature is 50-70 ℃, and the drying time is 1-5min.
In another aspect of the invention, the high-cycle-ratio diaphragm obtained by the preparation method is also included.
Compared with the prior art, the invention has the beneficial effects that:
1. the aluminum oxide and the PMMA on the surface of the high-circulation-rate diaphragm cooperatively play a role in improving the ionic conductivity of the diaphragm. The PMMA is mainly composed of polymethyl methacrylate, so that the cycle rate of the battery in the charging and discharging process can be effectively improved, as shown in figure 1, the spherical object on the coating is PMMA, the PMMA does not influence the shuttling of ions on the battery, and in addition, the particle size and the particle size distribution are uniform, so that the tensile resistance and the impact resistance of the diaphragm with the high cycle rate are enhanced, and the anti-manufacturing performance is strong (the rigidity is good, the impact deformation can be well resisted, and the characteristics cannot be changed after long-term use).
2. The high-cycle-rate diaphragm has the advantages that the space stability and the flatness are also improved, the thermal shrinkage rate is smaller, and the thermal runaway of the battery caused by short circuit due to thermal shrinkage is greatly avoided. For the separator using alumina and PVDF, the large amount of nano small spherical gel completely blocks the gaps of the alumina coating as shown in fig. 2, thereby reducing the shuttling capability of ions.
3. In the aspect of thickness, PMMA and PVDF play a role of a binder, and PMMA is embedded between the alumina coatings, so that the binding property of the diaphragm coating is improved, and the coating thickness is reduced; PVDF + alumina is sprayed after the alumina coating is coated, PVDF is adhered on the alumina coating, and the thickness of the coating is increased, so that the PMMA is arranged in a mode of increasing the adhesiveness of the diaphragm coating and reducing the thickness of the coating.
Drawings
FIG. 1 is a scanning electron microscope image of the surface of the diaphragm obtained in example 1, namely the diaphragm with high cycle rate under the synergistic action of alumina and PMMA.
Fig. 2 is a scanning electron microscope image of the surface of the separator obtained in comparative example 1, i.e., the separator using the synergistic effect of alumina and PVDF.
Detailed Description
Example 1
A preparation method of a high-cycle-rate diaphragm comprises the following steps:
step 1, the required raw materials are 7 parts by mass of PMMA (35% of solid content), 28 parts by mass of alumina, 55.8 parts by mass of pure water, 0.2 part by mass of dispersant, 4 parts by mass of isopropanol, 3 parts by mass of CMC (5% of solid content) and 0.04 part by mass of wetting agent; stirring and blending the dispersing agent and pure water for 5min in a planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the first time, wherein the stirring rotation speed is 3100r/min, the revolution speed is 20r/min, and then pouring the alumina powder into the planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for stirring and blending for the second time for 10min to obtain a mixed solution, wherein the stirring rotation speed of the device is 3100r/min, and the revolution speed is 20r/min; and simultaneously carrying out ultrasonic treatment (frequency of 50 KHZ) in the process of secondary stirring and blending; after the secondary stirring, adding isopropanol, CMC, PMMA and wetting agent into the mixed solution, and starting the planetary stirring equipment again (starting the vacuum function, adjusting the rotation speed of the equipment to 1000r/min, the revolution speed to 40r/min and the ultrasonic oscillation frequency to 5 kHz), and carrying out vacuum oscillation stirring and blending for 20min to prepare the coating slurry.
Step 2, placing the PE film on a coating machine filled with the coating slurry prepared in the step 1 for single-side coating, controlling the coating speed to be 30m/min, and controlling the thickness of the coated layer to be 2 microns to obtain a coating film;
and 3, drawing the coating film obtained in the step 2 by a drawing roller, and drying the coating film in a drying device for 5min at the drying temperature of 50 ℃ to obtain the high-circulation-ratio diaphragm.
Example 2
A preparation method of a high-cycle-rate diaphragm comprises the following steps:
step 1, the required raw materials are 8 parts by mass of PMMA (35% solid content), 29 parts by mass of alumina, 55.8 parts by mass of pure water, 0.2 part by mass of dispersant, 4 parts by mass of isopropanol, 2.95 parts by mass of CMC (5% solid content) and 0.05 part by mass of wetting agent; firstly, stirring and blending a dispersing agent and pure water for 5min in a planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the first time, wherein the stirring rotation speed is 3100r/min, the revolution speed is 20r/min, then pouring alumina powder into a stirring tank, and stirring and blending for 10min in the planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the second time to obtain a mixed solution, wherein the stirring rotation speed of the device is 3100r/min, and the revolution speed is 20r/min; and simultaneously carrying out ultrasonic treatment (frequency of 50 KHZ) in the process of secondary stirring and blending; after the secondary stirring, adding isopropanol, CMC, PMMA and wetting agent into the mixed solution, and starting the planetary stirring equipment again (starting the vacuum function, adjusting the rotation speed of the equipment to 1000r/min, the revolution speed to 40r/min and the ultrasonic oscillation frequency to 5 kHz), carrying out vacuum oscillation stirring and blending for 30min, and preparing the coating slurry.
Step 2, placing the PE film on a coating machine filled with the coating slurry prepared in the step 1 for single-side coating, controlling the coating speed to be 30m/min, and controlling the thickness of the coated layer to be 3 mu m to obtain a coating film;
and 3, drawing the coating film obtained in the step 2 by a drawing roll, and drying the coating film in a drying device for 5min at the drying temperature of 50 ℃ to obtain the high-circulation-ratio diaphragm.
Example 3
A preparation method of a high-cycle-rate diaphragm comprises the following steps:
step 1, 9 parts by mass of PMMA (35% of solid content), 28 parts by mass of alumina, 55.8 parts by mass of pure water, 0.2 part by mass of dispersant, 4 parts by mass of isopropanol, 2.96 parts by mass of CMC (5% of solid content) and 0.04 part by mass of wetting agent are required as raw materials; firstly, stirring and blending a dispersing agent and pure water for 5min in a planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) at a rotation speed of 3100r/min and a revolution speed of 20r/min for the first time, then pouring alumina powder into a stirring tank for secondary stirring and blending for 10min in the planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) to obtain a mixed solution, wherein the stirring rotation speed of the device is 3100r/min and the revolution speed of the device is 20r/min; and simultaneously carrying out ultrasonic treatment (frequency of 50 KHZ) in the process of secondary stirring and blending; after the secondary stirring, adding isopropanol, CMC, PMMA and wetting agent into the mixed solution, and starting the planetary stirring equipment again (starting the vacuum function, adjusting the rotation speed of the equipment to 1000r/min, the revolution speed to 40r/min and the ultrasonic oscillation frequency to 5 kHz), and carrying out vacuum oscillation stirring and blending for 35min to prepare the coating slurry.
Step 2, placing the PE film on a coating machine filled with the coating slurry prepared in the step 1 for single-side coating, controlling the coating speed to be 30m/min, and controlling the thickness of the coated layer to be 4 microns to obtain a coating film;
and 3, drawing the coating film obtained in the step 2 by a drawing roller, and drying the coating film in a drying device for 5min at the drying temperature of 50 ℃ to obtain the high-circulation-ratio diaphragm.
Comparative example 1
A preparation method of a battery separator comprises the following steps:
step 1, the required raw materials comprise 35 parts by mass of alumina, 55.8 parts by mass of pure water, 2 parts by mass of an adhesive (isooctyl acrylate), 0.2 part by mass of a dispersing agent, 4 parts by mass of isopropanol, 3 parts by mass of CMC (5% of solid content) and 0.05 part by mass of a wetting agent; firstly, stirring and blending a dispersing agent and pure water for 5min in a planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the first time, wherein the stirring rotation speed is 3100r/min, the revolution speed is 20r/min, then pouring alumina powder into the planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for stirring and blending for the second time for 10min, and obtaining a mixed solution, wherein the stirring rotation speed of the device is 3100r/min, and the revolution speed is 20r/min; and simultaneously carrying out ultrasonic treatment (frequency of 50 KHZ) in the process of secondary stirring and blending; after the secondary stirring, adding isopropanol, CMC, adhesive (isooctyl acrylate) and wetting agent into the mixed solution, and starting the stirring equipment again (starting the vacuum function, adjusting the rotation speed of the equipment to 1000r/min, the revolution speed to 40r/min and the ultrasonic oscillation frequency to 5 kHz), and carrying out vacuum oscillation stirring and blending for 25min to prepare the coating slurry.
And 2, placing the PE film on a coating machine filled with the coating slurry prepared in the step 1 for single-side coating, controlling the coating speed to be 30m/min, and controlling the thickness of the coated layer to be 2 microns to obtain the coating film.
And 3, drawing the coating film obtained in the step 2 by a drawing roll, and drying the coating film in a drying device for 5min at the drying temperature of 50 ℃ to obtain the primary coating film.
Step 4, taking the following raw materials in percentage by mass: 10% of PVDF, 75% of pure water, 0.2% of dispersing agent, 6.6% of isopropanol, 8% of CMC (5% of solid content) and 0.2% of wetting agent; firstly, stirring and blending a dispersing agent and pure water for 5min in a planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the first time, wherein the stirring rotation speed is 3100r/min, the revolution speed is 20r/min, then pouring PVDF powder into the planetary stirring device (with ultrasonic oscillation, vacuum and high-speed dispersion functions) for the second time, stirring and blending for 10min, and obtaining a mixed solution, wherein the stirring rotation speed of the device is 3100r/min, and the revolution speed is 20r/min; and simultaneously carrying out ultrasonic treatment (frequency of 50 KHZ) in the process of secondary stirring and blending; after the secondary stirring, adding isopropanol, CMC and wetting agent into the mixed solution, and starting the stirring device again (starting the vacuum function, adjusting the rotation speed of the device to 1000r/min, the revolution speed to 40r/min and the ultrasonic oscillation frequency to 5 kHz), and carrying out vacuum oscillation stirring and blending for 30min to prepare the coating slurry.
Step 5, placing the primary coating film obtained in the step 3 on a coating machine filled with the coating slurry prepared in the step 4 for single-side coating, controlling the coating speed to be 30m/min and the thickness of the coated coating layer to be 5 microns, and obtaining a secondary coating film;
and 6, drawing the secondary coating film obtained in the step 5 by a drawing roll, and drying the secondary coating film in drying equipment for 5min at the drying temperature of 50 ℃ to obtain the battery diaphragm.
The high cycle rate separators obtained in examples 1 to 3 and the separator obtained in comparative example 1 were all white and were tested, and the results are shown in table 1.
TABLE 1
Figure BDA0003857135130000051
The data show that the use of the PMMA coating can effectively improve the cycle rate of the battery in the charge and discharge process.
The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.

Claims (10)

1. The preparation method of the high-cycle-rate diaphragm is characterized by comprising the following steps of:
step 1, firstly stirring and blending a dispersing agent and pure water for the first time, then adding alumina powder for the second time, stirring and blending to obtain a mixed solution, simultaneously carrying out ultrasonic treatment in the process of stirring and blending for the second time, adding isopropanol, CMC, PMMA and a wetting agent into the mixed solution after stirring for the second time, and carrying out vacuum oscillation, stirring and blending to prepare a coating slurry; wherein, the mass parts ratio of PMMA, alumina, pure water, wetting agent, dispersant, isopropanol and CMC is (5-18): (20-30): (51.5-70.9): (0.03-0.09): (0.1-0.2): (3-6): (2.5-7);
step 2, coating the coating slurry obtained in the step 1 on a PE film to obtain a coating film;
and 3, drying the coating film obtained in the step 2 to obtain the high-circulation-ratio diaphragm.
2. The method according to claim 1, wherein in step 1, the dispersing agent is silicate and the wetting agent is sodium hexametaphosphate.
3. The preparation method according to claim 1, wherein in the step 1, the rotation speed of the primary stirring and blending is 2000-3100r/min, the revolution speed is 20-40r/min, and the stirring time is 5-45min.
4. The preparation method according to claim 1, wherein in the step 1, the rotation speed of the secondary stirring and blending is 2000-3100r/min, the revolution speed is 20-50r/min, and the stirring time is 10-30min.
5. The method for preparing the compound of claim 1, wherein the ultrasonic frequency in step 1 is 20-50KHZ.
6. The production method according to claim 1, wherein in the step 1, the rotation speed of the vacuum agitation and stirring blend is 1000 to 3000r/min, the revolution speed is 20 to 40r/min, the ultrasonic oscillation frequency is 5 to 60kHz, and the stirring time is 15 to 30min.
7. The method according to claim 1, wherein in the step 2, the coating is a single-side coating, the coating speed is 30 to 50m/min, and the coating thickness is 2 to 4 μm.
8. The method according to claim 1, wherein in the step 3, the drying is carried out by drawing the dried product into a drying device through a drawing roll.
9. The method according to claim 1, wherein in the step 3, the drying temperature is 50-70 ℃ and the drying time is 1-5min.
10. A high cycle rate separator produced by the production method according to any one of claims 1 to 9.
CN202211150890.5A 2022-09-21 2022-09-21 High-circulation-rate diaphragm and preparation method thereof Pending CN115483500A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211150890.5A CN115483500A (en) 2022-09-21 2022-09-21 High-circulation-rate diaphragm and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211150890.5A CN115483500A (en) 2022-09-21 2022-09-21 High-circulation-rate diaphragm and preparation method thereof

Publications (1)

Publication Number Publication Date
CN115483500A true CN115483500A (en) 2022-12-16

Family

ID=84424289

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211150890.5A Pending CN115483500A (en) 2022-09-21 2022-09-21 High-circulation-rate diaphragm and preparation method thereof

Country Status (1)

Country Link
CN (1) CN115483500A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106784533A (en) * 2017-01-20 2017-05-31 东莞市卓高电子科技有限公司 A kind of production technology containing PMMA and its copolymer coated barrier film
CN111769239A (en) * 2019-04-02 2020-10-13 河北金力新能源科技股份有限公司 Heat-resistant high-strength composite lithium battery diaphragm and preparation method and application thereof
CN113410577A (en) * 2021-05-20 2021-09-17 河北金力新能源科技股份有限公司 High-temperature-resistant high-insulation high-cycle lithium battery diaphragm and preparation method thereof
CN113991240A (en) * 2021-10-28 2022-01-28 河北金力新能源科技股份有限公司 Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof
CN114243208A (en) * 2021-11-30 2022-03-25 惠州锂威新能源科技有限公司 Composite diaphragm, preparation method thereof and secondary battery

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106784533A (en) * 2017-01-20 2017-05-31 东莞市卓高电子科技有限公司 A kind of production technology containing PMMA and its copolymer coated barrier film
CN111769239A (en) * 2019-04-02 2020-10-13 河北金力新能源科技股份有限公司 Heat-resistant high-strength composite lithium battery diaphragm and preparation method and application thereof
CN113410577A (en) * 2021-05-20 2021-09-17 河北金力新能源科技股份有限公司 High-temperature-resistant high-insulation high-cycle lithium battery diaphragm and preparation method thereof
CN113991240A (en) * 2021-10-28 2022-01-28 河北金力新能源科技股份有限公司 Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof
CN114243208A (en) * 2021-11-30 2022-03-25 惠州锂威新能源科技有限公司 Composite diaphragm, preparation method thereof and secondary battery

Similar Documents

Publication Publication Date Title
CN104269505B (en) A kind of composite lithium ion cell barrier film and preparation method thereof
CN104795541B (en) Lithium-ion battery negative electrode slurry preparation method
CN109244322B (en) Water-based coating for lithium ion battery diaphragm and preparation method and application thereof
CN109103441A (en) Modified composite material, preparation method and the purposes in lithium ion battery of siliceous substrates material
CN106848264A (en) A kind of porous silicon oxide lithium ion battery negative material and preparation method thereof
CN104966822A (en) Multilayer coated lithium titanate cathode material of lithium ion battery and preparation method of multilayer coated lithium titanate cathode material
CN102969489A (en) Silicon-carbon composite material, preparation method of silicon-carbon composite material, and lithium ion battery containing silicon-carbon composite material
CN110400927A (en) A kind of silicon-carbon composite anode material for lithium ion battery and preparation method thereof
CN104795568B (en) A kind of lithium ion power cell cathode slurry preparation method
CN110137449A (en) A kind of modified negative electrode material of lithium ion battery and its method of modifying
CN112142995A (en) Organic-inorganic composite grape particle structure material, slurry, diaphragm and preparation method
CN113424348B (en) Electrochemical device and electronic device
CN112635712A (en) Negative plate and lithium ion battery
CN113851609A (en) Silicon-based negative electrode plate, preparation method thereof and all-solid-state lithium ion battery
CN112216831B (en) Method for synthesizing high-capacity negative electrode material of lithium ion power battery
CN104852036B (en) The preparation method of ternary dynamic lithium battery and obtained ternary dynamic lithium battery
CN115642236B (en) Silicon-based anode material, preparation method and application thereof
CN107863500A (en) A kind of preparation method of pure lead lead carbon battery and pure lead lead carbon battery
CN115395002B (en) Porous silicon negative electrode material and preparation method thereof, silicon negative electrode piece and lithium ion battery
CN115483500A (en) High-circulation-rate diaphragm and preparation method thereof
CN110212184A (en) A kind of prelithiation method of carbon negative electrode material of lithium ion cell
CN116247157A (en) Method for preparing all-solid-state battery by dry method and all-solid-state battery
CN115275337A (en) Composite solid electrolyte membrane, preparation method thereof and lithium ion solid battery
CN112952029B (en) Silicon-oxygen-carbon lithium ion battery composite negative electrode slurry, preparation method thereof and lithium ion battery negative electrode prepared from silicon-oxygen-carbon lithium ion battery composite negative electrode slurry
CN114447338A (en) Positive pole piece slurry and preparation method thereof, lithium ion battery and vehicle

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination