[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

CN111354907A - PMMA polymer coating diaphragm and preparation method thereof - Google Patents

PMMA polymer coating diaphragm and preparation method thereof Download PDF

Info

Publication number
CN111354907A
CN111354907A CN202010206261.4A CN202010206261A CN111354907A CN 111354907 A CN111354907 A CN 111354907A CN 202010206261 A CN202010206261 A CN 202010206261A CN 111354907 A CN111354907 A CN 111354907A
Authority
CN
China
Prior art keywords
pmma
coating
dispersing
binder
pmma polymer
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
CN202010206261.4A
Other languages
Chinese (zh)
Inventor
张�杰
邓豪
庞冲
王娟
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.)
Anhui Xinheng New Material Technology Co ltd
Original Assignee
Anhui Xinheng New Material Technology 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 Anhui Xinheng New Material Technology Co ltd filed Critical Anhui Xinheng New Material Technology Co ltd
Priority to CN202010206261.4A priority Critical patent/CN111354907A/en
Publication of CN111354907A publication Critical patent/CN111354907A/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
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/411—Organic material
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D133/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers
    • C09D133/04—Homopolymers or copolymers of esters
    • C09D133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C09D133/10—Homopolymers or copolymers of methacrylic acid esters
    • C09D133/12—Homopolymers or copolymers of methyl methacrylate
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/60—Additives non-macromolecular
    • C09D7/63—Additives non-macromolecular organic
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/65—Additives macromolecular
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • 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
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00—Polymer mixtures characterised by other features
    • C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
    • C08L2205/035—Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend
    • 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)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Cell Separators (AREA)

Abstract

The invention discloses a PMMA polymer coating diaphragm and a preparation method thereof, belonging to the field of battery diaphragms. The PMMA polymer coating diaphragm comprises a base film and a PMMA polymer coating coated on at least one surface of the base film, wherein the PMMA polymer coating contains PMMA powder, a dispersing aid, a first binder and a second binder. According to the invention, by preparing the PMMA coating slurry and coating the PMMA coating slurry on the surface of the base film, the solubility of PMMA in a water system can be improved, PMMA powder can be effectively dispersed in the water system, the bonding strength of the diaphragm and the pole piece is enhanced, the problem of uneven coating of a PMMA polymer part is better solved, the phenomena of battery swelling and deformation are effectively inhibited, the hardness and consistency of the battery are improved, and the oxygen resistance and long-term cycle performance of the battery are improved.

Description

PMMA polymer coating diaphragm and preparation method thereof
Technical Field
The invention belongs to the field of battery diaphragms, and particularly relates to a PMMA polymer coating diaphragm and a preparation method thereof.
Background
Lithium Ion Batteries (LIBs) are the best battery systems in terms of comprehensive performance at present, have the characteristics of high specific energy, long cycle life, small volume, light weight, no memory effect, no pollution and the like, are rapidly developed into a new generation of energy storage power supply, and can be used for power support in the fields of information technology, electric vehicles, hybrid vehicles, aerospace and the like. The diaphragm, as one of the key inner layer components of the lithium ion battery, should have ionic conductivity and electronic insulation, good electrolyte wettability and sufficient liquid absorption and moisture retention capacity, and is required to have good spatial stability and flatness.
At present, with the increasing of the specific energy of the battery and the higher and higher requirements of customers on the safety performance of the battery, the common single-layer coating can not meet the current requirements, and the composite coating becomes a research hotspot. The common inorganic coating such as alumina can increase the high temperature resistance and thermal stability of the separator after coating, but the hardness of the battery is low after the battery is manufactured, and the battery core cannot be well protected, so that the polymer coating can be produced. The surface of the diaphragm is coated with a layer of polymer, the polymer can be well bonded with the polyolefin diaphragm and can be bonded with a battery pole piece at high temperature and high pressure, and therefore the hardness of the battery core is improved. However, due to the organic polar structure of the polymer coating, the solubility of the polymer coating in a water system is poor, the binding force of the diaphragm coating is insufficient, and part of the coating is uneven; if part of the oil-based production is used, the toxicity is high in the large-scale production process, and the harm to the human body is also high.
Through searching, relevant disclosures exist about the patent of polymer coating. For example, chinese patent application No. 201811008271.6 provides a polymer-coated separator for a lithium ion battery, the separator including a base film and a polymer distributed on the base film, the polymer being distributed in a manner including: convex points distributed at intervals and small points distributed sporadically. The granularity of the polymer of the application is about tens of microns, and although the polymer has better safety performance, the phenomena of uneven coverage rate, uneven distribution of internal resistance of the battery and the like exist when the separator is coated in the mode, and the consistency of the battery is reduced.
For another example, the application with chinese patent application No. 201810968413.7 provides a battery separator and a method for preparing the same, where the battery separator includes a base film and a PVDF/PMMA composite coating coated on at least one side of the base film, and the PVDF/PMMA composite coating is mainly prepared from the following raw materials in parts by weight: 25-35 parts of PVDF, 130 parts of PMMA 110-. Although the battery diaphragm prepared by the application has low air permeability increment, the diaphragm coating adhesion is still insufficient, and the rate discharge and cycle performance of the battery are still required to be further improved.
Disclosure of Invention
1. Problems to be solved
The invention aims to solve the problems of poor solubility of PMMA powder in a water system and uneven partial coating, and provides a PMMA polymer coating diaphragm and a preparation method thereof. By adopting the technical scheme of the invention, the solubility of PMMA in a water system can be improved, PMMA powder can be effectively dispersed in the water system, the bonding strength of the diaphragm and the pole piece is enhanced, the problem of uneven coating of a PMMA polymer part is better solved, the phenomena of bulging and deformation of the battery are effectively inhibited, the hardness and consistency of the battery are improved, and the oxygen resistance and long-term cycle performance of the battery are improved.
2. Technical scheme
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the membrane comprises a base membrane and a PMMA polymer coating coated on at least one surface of the base membrane, wherein the PMMA polymer coating contains PMMA powder, a dispersing aid, a first binder and a second binder.
Furthermore, the PMMA powder is preferably powder with the purity of more than 99 percent and the particle size of 800nm-5 mu m.
Furthermore, the dispersing auxiliary agent is a mixture of alcohol and an ammonium salt dispersing agent, wherein the alcohol is at least one of methanol, ethanol, isopropanol and polyethylene glycol, the ammonium salt dispersing agent is preferably polyacrylic ammonium salt, and the mixing ratio of the alcohol to the ammonium salt dispersing agent is 5: 1-10: 1.
further, the first binder is at least one of polyacrylic acid, styrene-butadiene latex, styrene acrylic acid, polyacrylamide, polyvinyl alcohol, polyethylene oxide, urethane acrylate, polyacrylate copolymer emulsion and urethane.
Still further, the second binder is at least one of alkoxy polysiloxane, methoxy polysiloxane, ethoxy polysiloxane, and methacryloxy polysiloxane.
Furthermore, the PMMA polymer coating also contains deionized water, a thickening agent and a surfactant.
Further, the surfactant is at least one of polyoxyethylene alkylated ethers, thiols, hydrazides and thiol acetals, and the thickener is an aqueous solution prepared from at least one of sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose and sodium alginate.
Furthermore, the PMMA composite coating is prepared from the following raw material components in parts by weight: 15-25 parts of PMMA powder, 1-5 parts of dispersing aid, 3-7 parts of first binder, 0.02-0.1 part of second binder, 40-60 parts of deionized water, 3-8 parts of thickener and 0.1-0.4 part of surfactant.
The preparation method of the PMMA polymer coating diaphragm comprises the following steps:
step one, preparing PMMA coating slurry
Adding a dispersing aid into PMMA powder for premixing, adding deionized water into the premixed powder for stirring and dispersing, then adding a first binder and a second binder for stirring and dispersing, then adding a thickening agent for stirring and dispersing again, and finally adding a surfactant for stirring and dispersing to obtain uniformly mixed PMMA coating slurry;
step two, coating
And coating the PMMA coating slurry on one side or two sides of the base film in a roll coating mode, and drying to obtain the PMMA polymer coating diaphragm.
Furthermore, the rotating speed of the stirring dispersion in the first step is 700-; and in the second step, the thickness of the coating is controlled to be 1-5 mu m.
3. Advantageous effects
Compared with the prior art, the invention has the beneficial effects that:
(1) according to the PMMA polymer coating diaphragm, the PMMA polymer is used as the diaphragm coating, the raw material components of the PMMA polymer coating are optimized, and the proportion of the components is optimally designed, so that the dispersion effect of PMMA powder is improved, the solubility of PMMA in a water system is improved, the binding force of the diaphragm coating is enhanced, the problem of uneven coating of the PMMA polymer part is solved, the swelling and deformation phenomena of a battery are effectively inhibited, the hardness and the consistency of the battery are improved, and the oxygen resistance and the long-term cycle performance of the battery are improved.
(2) According to the PMMA polymer coating diaphragm, the second binder is added into the raw materials of the PMMA polymer coating, and the components of the second binder are optimized, so that the interface action between an inorganic substance and an organic substance can be improved, the bonding performance of the material is further improved, the bonding strength between the polymer and the diaphragm and between the polymer and the inorganic substance coating pole piece is improved, a uniform coating layer is formed on the surface of the coated particles, and the possibility of powder falling is reduced.
(3) According to the PMMA polymer coating diaphragm, the mixture of the alcohol and the ammonium salt dispersant is used as the dispersing aid, and the specific components and the mixing ratio of the alcohol and the ammonium salt dispersant are optimally selected, so that the compatibility of PMMA powder and deionized water can be effectively improved, the dispersibility of the PMMA powder is further enhanced, the bonding strength is improved, and the coating uniformity of a PMMA coating is ensured.
(4) According to the PMMA polymer coating diaphragm, the purity and the particle size of PMMA powder in the raw materials are optimized, and the PMMA raw materials with more uniform particle size distribution are selected, so that the coating uniformity of the PMMA coating can be further ensured, the adhesive force of the coating of the diaphragm is enhanced, and the possibility of powder falling is reduced. In addition, the invention also optimizes the proportion of the PMMA powder, the dispersing auxiliary agent, the first binder, the second binder and other components in the PMMA polymer coating, so that the PMMA powder can be effectively dispersed in a water system, the bonding strength of the diaphragm and the pole piece is further enhanced, the coating uniformity is ensured, the yield of battery production is improved, and the oxygen resistance and the safety performance are improved.
(5) According to the PMMA polymer coating diaphragm, the polymer coating has a swelling phenomenon when being heated, so that the diaphragm and a pole piece can be bonded, the battery swelling and deformation can be effectively inhibited, the battery hardness is improved, the battery shape is maintained, and the problem of battery core shell entering is solved under the condition of ensuring the completion of liquid injection; meanwhile, the method can help to timely remove gas generated in the formation process of the battery, reduce electrode collapse caused by side reaction, reduce damage to an SEI film and improve oxygen resistance. In addition, the particle size of the polymer coating is 2-3 microns of a spherical structure, so that a larger gap can be formed, the liquid retention rate is improved, the circulating impedance is reduced, the ionic conductivity is improved, and the long-term circulating performance of the battery is enhanced.
(6) The preparation method of the PMMA polymer coating diaphragm comprises two steps of PMMA coating slurry preparation and PMMA coating, and the preparation process and parameters of the PMMA polymer coating diaphragm are optimally designed in the preparation process, so that the dispersion effect of PMMA powder is improved, the PMMA powder can be effectively dispersed in a water system, the bonding strength of the diaphragm and a pole piece is enhanced, a uniform coating layer is formed on the surface of coated particles, the battery bulging and deformation phenomena are effectively inhibited, the hardness and the consistency of the battery are improved, and the oxygen resistance and the long-term cycle performance of the battery are improved.
Drawings
FIG. 1 is an electron micrograph of a polymer-coated separator obtained in example 1 of the present invention;
fig. 2 is an electron micrograph of the polymer-coated separator obtained in example 2 of the present invention.
Detailed Description
At present, after a common inorganic coating is coated, although the high-temperature resistance and the thermal stability of a diaphragm can be improved, the hardness of a battery manufactured into the battery is lower, and a battery cell cannot be well protected, so that a polymer coating needs to be bonded with a battery pole piece, and the hardness of the battery cell is improved. However, the polymer coating has poor solubility in a water system due to the organic polar structure of the polymer coating, the binding force of the diaphragm coating is insufficient, the coating is partially uneven, the oxygen resistance and the long-term cycle performance of the polymer coating cannot be guaranteed, and the safety performance of the battery is not high.
Based on the above situation, the inventors of the present invention provide a PMMA polymer coating membrane, which comprises a base membrane and a PMMA polymer coating layer coated on at least one surface of the base membrane, wherein the PMMA polymer coating layer contains PMMA powder, a dispersion aid, a first binder, a second binder, deionized water, a thickener and a surfactant. The PMMA powder is preferably powder with the purity of more than 99 percent, the particle size of the PMMA powder is 800nm-5 mu m, and PMMA powder raw materials with more uniform particle size distribution are selected by preferably selecting the purity and the particle size of the PMMA powder, so that the average particle size of the particle size is controlled to be uniform, the PMMA powder can be effectively dispersed in a water system, and the uniform coating of the PMMA powder is ensured.
The dispersing auxiliary agent is a mixture of alcohol and an ammonium salt dispersing agent, wherein the alcohol is at least one of methanol, ethanol, isopropanol and polyethylene glycol, and the alcohol is a low-polarity substance, so that the compatibility of PMMA powder and deionized water can be effectively improved after the alcohol is added, a strong defoaming effect is realized, and the bonding strength is improved; the ammonium salt dispersant is preferably polyacrylic acid ammonium salt, so that the polyacrylic acid ammonium salt dispersant can be better compatible with PMMA, and many side chain carboxyl groups in the molecular structure of polyacrylic acid determine that the ionic property and the steric hindrance effect of the polyacrylic acid ammonium salt dispersant are better than those of other common polycarboxylic acids. The mixing ratio of the alcohol and the ammonium salt dispersant is 5: 1-10: 1, a mixture of alcohol and an ammonium salt dispersant is used as a dispersing aid, and specific components and mixing proportion of the dispersing aid are optimally selected, so that the dispersibility of PMMA powder is further enhanced, the bonding strength is improved, and the uniform coating of PMMA polymer is promoted.
The first binder is at least one of polyacrylic acid, styrene-butadiene latex, cinnamic acid, polyacrylamide, polyvinyl alcohol, polyethylene oxide, polyurethane acrylate, polyacrylate copolymer emulsion and carbamate; the second binder is at least one of alkoxy polysiloxane, methoxy polysiloxane, ethoxy polysiloxane and methacryloxy polysiloxane, and the molecular structure of the second binder contains two groups with different chemical properties, wherein one group is an inorganophile group and is easy to chemically react with the surface of an inorganic substance, and the other group is an organophilic group and can chemically react with synthetic resin or other polymers or generate hydrogen bonds to be dissolved in the inorganophile group to serve as a molecular bridge, so that the interface action between the inorganic substance and the organic substance is improved, and the bonding performance of the material is improved.
The surfactant is at least one of polyoxyethylene alkylated ethers, thiols, hydrazides and thiol acetals; the thickener can be an aqueous solution prepared from at least one of sodium carboxymethylcellulose, methylcellulose, hydroxypropyl methylcellulose, hydroxyethyl cellulose and sodium alginate. The PMMA composite coating is prepared from the following raw material components in parts by weight: 15-25 parts of PMMA powder, 1-5 parts of dispersing aid, 3-7 parts of first binder, 0.02-0.1 part of second binder, 40-60 parts of deionized water, 3-8 parts of thickening agent and 0.1-0.4 part of surfactant, wherein the second binder is preferably 1-3% of the first binder. According to the invention, the PMMA polymer is used as the diaphragm coating, the raw material components and the proportion of the PMMA polymer coating are optimally designed, the mixture of alcohols and an ammonium salt dispersant is used as a dispersing aid, the second binder is added into the raw material of the PMMA polymer coating, and the components and the mixing proportion of the second binder and the dispersing aid are optimally designed, so that the PMMA polymer is more uniformly dispersed in a water system, the consistency of products is improved, the bonding performance of the materials is improved, a uniform coating layer is formed on the surface of coated particles, the yield of battery production is improved, and the oxygen resistance and the safety performance of the battery are improved.
The invention also selects the PMMA raw material with more uniform particle size distribution by optimizing the purity and particle size of the PMMA powder in the raw material, thereby further ensuring the coating uniformity of the PMMA coating, enhancing the binding force of the diaphragm coating and reducing the possibility of powder falling. The polymer coating can generate a swelling process when being heated, and can bond the diaphragm and the pole piece, so that the battery is more effectively inhibited from bulging and deforming, the battery hardness is improved, the battery shape is maintained, and the problem of battery core entering the shell is solved under the condition of ensuring the completion of liquid injection; and the gas generated in the battery formation process can be timely discharged, the electrode collapse caused by side reaction is reduced, the damage to an SEI film is reduced, and the oxygen resistance is improved. In addition, the polymer coating has a 2-3 micron spherical structure, so that a larger gap can be formed, the liquid retention rate is improved, the circulating impedance is reduced, the ionic conductivity is improved, and the long-term circulating performance of the battery is enhanced.
The preparation method of the PMMA polymer coating diaphragm comprises the following steps:
step one, preparing PMMA coating slurry
Weighing 15-25 parts of PMMA powder in a container, and adding 1-5 parts of a dispersing aid into the PMMA powder for premixing; adding 40-60 parts of deionized water into the premixed powder, and dispersing for 10-20min under the stirring of the rotating speed of 700-1000r/min, wherein the dispersion process reduces the distance between a polar substance and a non-polar substance, improves potential energy and surface energy, and possibly causes the temperature reduction phenomenon, and belongs to the normal phenomenon; then adding 3-7 parts of first binder and 0.02-0.1 part of second binder, and dispersing for 15-30min under the stirring of the rotation speed of 700-; then adding 3-8 parts of thickening agent and dispersing for 10-20min under the stirring of the rotating speed of 700 plus 1000r/min, finally adding 0.1-0.4 part of surfactant and dispersing for 10-20min under the stirring of the rotating speed of 700 plus 1000r/min to obtain the uniformly mixed PMMA coating slurry.
Step two, coating
And coating the PMMA coating slurry on one side or two sides of the base film in a roll coating mode, wherein the coating uniformity can be better ensured by coating in the roll coating mode, and the PMMA polymer coating diaphragm is obtained after drying. When the PMMA coating slurry is coated, the PMMA coating slurry can be directly coated on the surface of a base film or an inorganic coating, the thickness of the coating is controlled to be 1-5 mu m, so that a uniform coating is formed on the surface of coated particles, the cost is increased due to the fact that the coating is too thick, the internal resistance of a diaphragm is increased, and the ventilation is increased. The method can also directly use the micro-concave plate coating, and is consistent with the common ceramic coating without purchasing or replacing equipment.
The invention is further described with reference to specific examples.
Example 1
The preparation method of the PMMA polymer coating membrane of the embodiment includes the following steps:
weighing 20 parts of PMMA powder in a container, and adding 2 parts of dispersing aid into the PMMA powder for premixing; adding 40 parts of deionized water into the premixed powder, and dispersing for 10min under stirring at the rotating speed of 900 r/min; then adding 3 parts of first binder and 0.06 part of second binder, and dispersing for 20min under stirring at the rotating speed of 900 r/min; then adding 5 parts of thickening agent, dispersing for 10min under the stirring of the rotation speed of 900r/min, finally adding 0.15 part of surfactant, and dispersing for 10min under the stirring of the rotation speed of 900r/min to obtain the uniformly mixed water-based coating slurry.
And (3) coating the PMMA coating slurry on one side of a base film in a gravure coating mode, wherein the base film for coating is a 12-micron diaphragm, the coating thickness of the base film is controlled to be 2 microns by gravure coating, and drying is carried out to obtain the PMMA polymer coating diaphragm, wherein the structure of the PMMA polymer coating diaphragm is shown in figure 1. Overlapping the coated diaphragm and the pole piece together, and bonding the diaphragm and the pole piece together through a hot pressing process, wherein the preferred hot pressing process is as follows: 1MPa, 10 s. Taking 3 groups of experimental samples, respectively testing the peel strength and the liquid absorption rate of the experimental samples through a universal testing machine.
Example 2
The preparation method of the PMMA polymer coating membrane of the embodiment includes the following steps:
weighing 15 parts of PMMA powder in a container, and adding 2 parts of dispersing aid into the PMMA powder for premixing; adding 45 parts of deionized water into the premixed powder, and dispersing for 10min under stirring at the rotating speed of 900 r/min; then adding 3 parts of first binder and 0.06 part of second binder, and dispersing for 20min under stirring at the rotating speed of 900 r/min; then adding 5 parts of thickening agent, dispersing for 10min under the stirring of the rotation speed of 900r/min, finally adding 0.2 part of surfactant, and dispersing for 10min under the stirring of the rotation speed of 900r/min to obtain the uniformly mixed water-based coating slurry.
And (3) coating the PMMA coating slurry on one side of the base film by adopting a gravure coating mode, controlling the coating thickness of the PMMA coating slurry to be 2 microns by adopting gravure coating, ensuring that the coating particles form a uniform coating on the surface, ensuring the coating coverage rate to be about 60 percent, and obtaining the PMMA polymer coating diaphragm after coating and drying, wherein the structure of the PMMA polymer coating diaphragm is shown in figure 2. Overlapping the coated diaphragm and the pole piece together, and bonding the diaphragm and the pole piece together through a hot pressing process, wherein the preferred hot pressing process is as follows: 1MPa, 10 s. 3 groups of experimental samples were taken, and the peel strength and the liquid absorption rate were measured by a universal tester, and the test results of example 1 and example 2 are shown in the following table.
Peel strength N/m Example 1 Example 2
Sample 1 14.3 12.2
Sample 2 14.0 12.3
Sample 3 14.6 12.5
Mean value gf/10mm 14.3 12.3
The liquid absorption rate% Example 1 Example 2
Sample 1 253 181
Sample 2 260 196
Sample 3 240 184
Mean value 250 187
Example 3
The preparation method of the PMMA polymer coating membrane of the embodiment includes the following steps:
weighing 25 parts of PMMA powder in a container, adding 5 parts of dispersing aid for premixing, wherein the mixing ratio of alcohol and ammonium salt dispersant in the dispersing aid is 5: 1; adding 60 parts of deionized water into the premixed powder, and dispersing for 15min under stirring at the rotating speed of 1000 r/min; then adding 7 parts of first binder and 0.1 part of second binder, and dispersing for 30min under stirring at the rotating speed of 1000 r/min; then 8 parts of thickening agent is added and dispersed for 20min under the stirring of the rotating speed of 700r/min, finally 0.4 part of surfactant is added and dispersed for 15min under the stirring of the rotating speed of 1000r/min, and then the evenly mixed water-based coating slurry can be obtained.
And coating the PMMA coating slurry on two sides of the base film in a roller coating mode, controlling the thickness of the coating to be 3 mu m, and coating and drying to obtain the PMMA polymer coating diaphragm.
Example 4
The preparation method of the PMMA polymer coating membrane of the embodiment includes the following steps:
weighing 15 parts of PMMA powder in a container, adding 1 part of dispersing aid for premixing, wherein the mixing ratio of alcohol and ammonium salt dispersant in the dispersing aid is 10: 1; adding 50 parts of deionized water into the premixed powder, and dispersing for 20min under stirring at the rotating speed of 700 r/min; then adding 5 parts of first binder and 0.02 part of second binder, and dispersing for 30min under stirring at the rotating speed of 700 r/min; then adding 3 parts of thickening agent, dispersing for 15min under the stirring of the rotating speed of 1000r/min, finally adding 0.1 part of surfactant, and dispersing for 20min under the stirring of the rotating speed of 700r/min to obtain the uniformly mixed water-based coating slurry.
And coating the PMMA coating slurry on two sides of the base film in a roller coating mode, controlling the thickness of the coating to be 1 mu m, and coating and drying to obtain the PMMA polymer coating diaphragm.
Example 5
Weighing 20 parts of PMMA powder in a container, adding 3 parts of dispersing aid for premixing, wherein the mixing ratio of alcohol and ammonium salt dispersant in the dispersing aid is 8: 1; adding 50 parts of deionized water into the premixed powder, and dispersing for 15min under stirring at the rotating speed of 900 r/min; then adding 5 parts of first binder and 0.06 part of second binder, and dispersing for 15min under stirring at the rotating speed of 900 r/min; and then adding 5 parts of thickening agent, dispersing for 15min under the stirring of the rotation speed of 900r/min, finally adding 0.2 part of surfactant, and dispersing for 20min under the stirring of the rotation speed of 900r/min to obtain the uniformly mixed water-based coating slurry.
And coating the PMMA coating slurry on two sides of the base film in a roller coating mode, controlling the thickness of the coating to be 5 mu m, and coating and drying to obtain the PMMA polymer coating diaphragm.

Claims (10)

1. A PMMA polymer coated membrane characterized in that: the diaphragm comprises a base film and a PMMA polymer coating coated on at least one surface of the base film, wherein the PMMA polymer coating contains PMMA powder, a dispersing aid, a first binder and a second binder.
2. A PMMA polymer coated membrane according to claim 1, wherein: the PMMA powder is preferably powder with the purity of more than 99 percent, and the particle size of the PMMA powder is 800nm-5 mu m.
3. A PMMA polymer coated membrane according to claim 2, wherein: the dispersing auxiliary agent is a mixture of alcohol and an ammonium salt dispersing agent, wherein the alcohol is at least one of methanol, ethanol, isopropanol and polyethylene glycol, the ammonium salt dispersing agent is preferably polyacrylic ammonium salt, and the mixing ratio of the alcohol to the ammonium salt dispersing agent is 5: 1-10: 1.
4. a PMMA polymer coated membrane according to claim 3, wherein: the first binder is at least one of polyacrylic acid, styrene-butadiene latex, cinnamic acid, polyacrylamide, polyvinyl alcohol, polyethylene oxide, polyurethane acrylate, polyacrylate copolymer emulsion and carbamate.
5. A PMMA polymer coated membrane according to claim 4, characterized in that: the second adhesive is at least one of alkoxy polysiloxane, methoxy polysiloxane, ethoxy polysiloxane and methacryloxy polysiloxane.
6. A PMMA polymer coated membrane according to any one of claims 1-5, characterized in that: the PMMA polymer coating also contains deionized water, a thickening agent and a surfactant.
7. A PMMA polymer coated membrane according to claim 6, characterized in that: the surfactant is at least one of polyoxyethylene alkylated ether, thiol, hydrazide and thiol acetal, and the thickener is an aqueous solution prepared from at least one of sodium carboxymethylcellulose, methylcellulose, hydroxypropyl methylcellulose, hydroxyethyl cellulose and sodium alginate.
8. A PMMA polymer coated membrane according to claim 7, characterized in that: the PMMA composite coating is prepared from the following raw material components in parts by weight: 15-25 parts of PMMA powder, 1-5 parts of dispersing aid, 3-7 parts of first binder, 0.02-0.1 part of second binder, 40-60 parts of deionized water, 3-8 parts of thickener and 0.1-0.4 part of surfactant.
9. A method for preparing a PMMA polymer coated membrane as defined in any one of claims 1-8, characterized in that it comprises the following steps:
step one, preparing PMMA coating slurry
Adding a dispersing aid into PMMA powder for premixing, adding deionized water into the premixed powder for stirring and dispersing, then adding a first binder and a second binder for stirring and dispersing, then adding a thickening agent for stirring and dispersing again, and finally adding a surfactant for stirring and dispersing to obtain uniformly mixed PMMA coating slurry;
step two, coating
And coating the PMMA coating slurry on one side or two sides of the base film in a roll coating mode, and drying to obtain the PMMA polymer coating diaphragm.
10. A method for preparing a PMMA polymer coated membrane according to claim 9, wherein: the rotating speed is 700-1000r/min when stirring and dispersing are carried out in the first step, the dispersing time is 10-20min when deionized water, a thickening agent or a surfactant are added for stirring and dispersing, and the dispersing time is 15-30min when a first binder and a second binder are added for stirring and dispersing; and in the second step, the thickness of the coating is controlled to be 1-5 mu m.
CN202010206261.4A 2020-03-23 2020-03-23 PMMA polymer coating diaphragm and preparation method thereof Pending CN111354907A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010206261.4A CN111354907A (en) 2020-03-23 2020-03-23 PMMA polymer coating diaphragm and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010206261.4A CN111354907A (en) 2020-03-23 2020-03-23 PMMA polymer coating diaphragm and preparation method thereof

Publications (1)

Publication Number Publication Date
CN111354907A true CN111354907A (en) 2020-06-30

Family

ID=71197691

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010206261.4A Pending CN111354907A (en) 2020-03-23 2020-03-23 PMMA polymer coating diaphragm and preparation method thereof

Country Status (1)

Country Link
CN (1) CN111354907A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112563583A (en) * 2020-12-10 2021-03-26 珠海冠宇电池股份有限公司 Lithium battery
CN114221088A (en) * 2021-11-30 2022-03-22 中材锂膜有限公司 High-adhesion-strength PVDF (polyvinylidene fluoride) coated diaphragm and preparation method thereof
CN115810873A (en) * 2022-10-24 2023-03-17 宁德时代新能源科技股份有限公司 Battery pack, battery cell, secondary battery, and power consumption device
CN118198653A (en) * 2022-12-05 2024-06-14 蜂巢能源科技(上饶)有限公司 Secondary battery diaphragm coating slurry, composite diaphragm and preparation method

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1788038A (en) * 2003-05-13 2006-06-14 德古萨公司 Organofunctional siloxane mixtures
CN1816590A (en) * 2003-07-03 2006-08-09 德古萨公司 Silane formulation with high filler content
CN101546822A (en) * 2008-03-27 2009-09-30 三星Sdi株式会社 Electrode assembly and secondary battery having the same
CN101630758A (en) * 2008-07-16 2010-01-20 比亚迪股份有限公司 Lithium-ion secondary battery and preparation method thereof
CN104479132A (en) * 2014-12-05 2015-04-01 东莞兆舜有机硅新材料科技有限公司 Alkoxy-terminated 107 adhesive, and preparation method and application thereof
CN105542169A (en) * 2016-02-01 2016-05-04 江西省科学院应用化学研究所 Preparation method for alkoxy functionalized polysiloxane
CN106784532A (en) * 2016-08-29 2017-05-31 东莞市卓高电子科技有限公司 The preparation method of aqueous PVDF and its copolymer composite coated barrier film
CN107002357A (en) * 2014-10-15 2017-08-01 诺普科纸技术股份有限公司 Method for controlling Stickies deposit in slurrying and paper-making process
CN108807804A (en) * 2018-08-23 2018-11-13 河北金力新能源科技股份有限公司 Battery separator and preparation method thereof
CN108987650A (en) * 2018-07-20 2018-12-11 河北金力新能源科技股份有限公司 Battery separator and preparation method thereof and battery
CN110760279A (en) * 2019-10-22 2020-02-07 东莞市卓高电子科技有限公司 High-cohesiveness water-based slurry for diaphragm and lithium ion battery diaphragm manufactured by using same

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1788038A (en) * 2003-05-13 2006-06-14 德古萨公司 Organofunctional siloxane mixtures
CN1816590A (en) * 2003-07-03 2006-08-09 德古萨公司 Silane formulation with high filler content
CN101546822A (en) * 2008-03-27 2009-09-30 三星Sdi株式会社 Electrode assembly and secondary battery having the same
CN101630758A (en) * 2008-07-16 2010-01-20 比亚迪股份有限公司 Lithium-ion secondary battery and preparation method thereof
CN107002357A (en) * 2014-10-15 2017-08-01 诺普科纸技术股份有限公司 Method for controlling Stickies deposit in slurrying and paper-making process
CN104479132A (en) * 2014-12-05 2015-04-01 东莞兆舜有机硅新材料科技有限公司 Alkoxy-terminated 107 adhesive, and preparation method and application thereof
CN105542169A (en) * 2016-02-01 2016-05-04 江西省科学院应用化学研究所 Preparation method for alkoxy functionalized polysiloxane
CN106784532A (en) * 2016-08-29 2017-05-31 东莞市卓高电子科技有限公司 The preparation method of aqueous PVDF and its copolymer composite coated barrier film
CN108987650A (en) * 2018-07-20 2018-12-11 河北金力新能源科技股份有限公司 Battery separator and preparation method thereof and battery
CN108807804A (en) * 2018-08-23 2018-11-13 河北金力新能源科技股份有限公司 Battery separator and preparation method thereof
CN110760279A (en) * 2019-10-22 2020-02-07 东莞市卓高电子科技有限公司 High-cohesiveness water-based slurry for diaphragm and lithium ion battery diaphragm manufactured by using same

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
崔庭昌, 《石油石化工程-数码设计》, vol. 6, no. 4, pages 216 - 293 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112563583A (en) * 2020-12-10 2021-03-26 珠海冠宇电池股份有限公司 Lithium battery
CN114221088A (en) * 2021-11-30 2022-03-22 中材锂膜有限公司 High-adhesion-strength PVDF (polyvinylidene fluoride) coated diaphragm and preparation method thereof
CN115810873A (en) * 2022-10-24 2023-03-17 宁德时代新能源科技股份有限公司 Battery pack, battery cell, secondary battery, and power consumption device
CN118198653A (en) * 2022-12-05 2024-06-14 蜂巢能源科技(上饶)有限公司 Secondary battery diaphragm coating slurry, composite diaphragm and preparation method

Similar Documents

Publication Publication Date Title
CN111354907A (en) PMMA polymer coating diaphragm and preparation method thereof
CN113178663A (en) Composite diaphragm and preparation method and application thereof
CN104466188B (en) Multilayer composite positive pole piece, preparation method of pole piece and lithium ion battery applying pole piece
CN110137466A (en) Lithium ion battery silicon-carbon-carbon nanotube composite microsphere negative electrode material preparation method
CN109088031A (en) Ceramic coating membrane slurry, Ceramic Composite diaphragm and its preparation method and application
CN109004220A (en) A kind of boronic acid compounds modification lithium ion battery silicium cathode and preparation method thereof
WO2021195835A1 (en) Pre-lithiated negative electrode and preparation method therefor, and lithium ion battery and supercapacitor having pre-lithiated negative electrode
CN106058126A (en) Functional coating diaphragm and battery containing same
CN106450315B (en) A kind of high performance carbon paper base electrode anode material and its preparation method and application
CN111009665A (en) Microporous layer, gas diffusion layer, preparation method and application thereof
CN117497835A (en) Solid-state battery cell, preparation method thereof and solid-state battery
CN111312967B (en) Ceramic coating slurry and preparation method thereof, lithium battery diaphragm and lithium battery
CN113851609A (en) Silicon-based negative electrode plate, preparation method thereof and all-solid-state lithium ion battery
CN109411673A (en) Lithium ion battery separator slurry and preparation method and lithium ion battery separator
CN108878893A (en) A kind of fast charge negative electrode of lithium ion battery modified collector and preparation method thereof
CN109698330B (en) Lithium ion battery
CN102522209B (en) Preparation method of cathode negative plate slurry of high-energy nickel-carbon supercapacitor
CN108630869A (en) A kind of diaphragm, preparation method and lithium battery
CN109301218A (en) A kind of preparation method of lithium manganate battery cathode
CN113725013A (en) Preparation method of current collector-free electrode and application of current collector-free electrode in super capacitor
CN108899518A (en) A kind of flexible lithium stearate cladding nanometer silicon composite material of core-shell structure and its preparation and application
CN111816823A (en) Thermal self-closing ceramic modified diaphragm and preparation method thereof
CN102354616A (en) Negative plate slurry of high-energy nickel/carbon super capacitor
CN116014069A (en) Pre-lithiated composite negative electrode plate, preparation method thereof and lithium ion battery
CN114914402A (en) Conductive carbon slurry, positive electrode slurry, and preparation method and application thereof

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
CB02 Change of applicant information
CB02 Change of applicant information

Address after: 243000 No. 891, Yinhuang East Road, economic and Technological Development Zone, Maanshan City, Anhui Province

Applicant after: Anhui Jinli new energy Co.,Ltd.

Address before: 243071 No. 891, Yinhuang East Road, intersection of Jiangdong Avenue and Yinhuang Road, economic and Technological Development Zone, Ma'anshan City, Anhui Province

Applicant before: ANHUI XINHENG NEW MATERIAL TECHNOLOGY Co.,Ltd.

RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20200630