CN107240663B - Polymer coating diaphragm and preparation method thereof - Google Patents
Polymer coating diaphragm and preparation method thereof Download PDFInfo
- Publication number
- CN107240663B CN107240663B CN201710299391.5A CN201710299391A CN107240663B CN 107240663 B CN107240663 B CN 107240663B CN 201710299391 A CN201710299391 A CN 201710299391A CN 107240663 B CN107240663 B CN 107240663B
- Authority
- CN
- China
- Prior art keywords
- polymer
- polymer coating
- coating
- parts
- 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.)
- Active
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
-
- 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
-
- 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
The invention discloses a polymer coating diaphragm and a preparation method thereof, wherein the polymer coating diaphragm consists of a polyolefin microporous membrane and a polymer coating formed by polymer coating slurry coated on the polyolefin microporous membrane; the polymer coating slurry consists of the following raw materials in parts by mass: 100 parts of main polymer, 10-30 parts of auxiliary polymer, 300-900 parts of mixed solvent, 5-20 parts of pore-foaming agent and 3-10 parts of surfactant. The polymer coating slurry has the advantages that the polymer coating slurry has strong stability, strong adhesive force of the polymer coating and difficult shedding due to the adoption of the auxiliary polymer and the mixed solvent containing the ionic liquid; the production of the composite diaphragm cannot be influenced even if the composite diaphragm is placed for 72 hours and then used, the product performance cannot be influenced even if the composite diaphragm is placed for 48 hours, the polymer coating endows the composite diaphragm with functions of heat resistance, lyophilic and the like, and the safety performance and the ion permeability of the diaphragm are improved.
Description
Technical Field
The invention relates to the technical field of lithium ion battery diaphragms, in particular to a polymer coating diaphragm and a preparation method thereof.
Background
Because the lithium ion battery has the advantages of high working voltage, high energy density, no memory effect, long cycle life and the like, the lithium ion battery is widely applied to the fields of portable digital equipment, electric tools, electric automobiles and the like.
The separator is an indispensable component in the lithium ion battery, and the main function of the separator is to isolate the positive electrode and the negative electrode from direct contact and prevent short circuit, and simultaneously allow ions in the electrolyte to freely pass through. The performance of the separator can affect the internal resistance of the battery and the interface structure of the battery, thereby affecting the energy output, power output, cycle life and the like of the lithium ion battery. Therefore, the lithium ion battery separator should have good electronic insulation, heat resistance stability, electrolyte wettability, chemical stability, and the like.
Currently mainstream commercial separators are polyolefin-based separators such as polypropylene microporous membranes, polyethylene microporous membranes, and polyethylene/polypropylene composite multilayer microporous membranes. Due to the inherent properties of materials such as polypropylene, polyethylene and the like, the polyolefin diaphragm has good chemical stability and mechanical strength at a lower temperature; however, the melting point of the polyolefin separator is low, and under the condition of high temperature, the polyolefin microporous membrane can shrink in a large area to cause short circuit of the battery and cause thermal runaway, so that the battery can catch fire and even explode. In addition, the polyolefin microporous membrane has poor wettability to the electrolyte and weak absorption and retention capacity of the electrolyte, so that a large risk of leakage of the electrolyte exists, and the cyclic charge and discharge performance, the cyclic service life and the like of the battery are influenced.
The heat resistance of the diaphragm can be obviously improved by coating inorganic particles on the polyolefin microporous membrane by adopting blade coating or gravure coating, but the inorganic particles are easy to agglomerate and have poor coating uniformity due to the small particle size and large specific surface area of the inorganic particles; and the inorganic particle coating and the polyolefin microporous membrane have poor adhesion, and obvious inorganic particle shedding phenomenon exists. Therefore, coating the polyolefin with inorganic particles has a limited degree of improvement in separator performance.
The electrolyte wettability and the heat-resistant stability of the separator can be improved to a certain extent by coating the polymer with a higher melting point on the surface of the polyolefin microporous membrane. Polyvinylidene fluoride or vinylidene fluoride-hexafluoropropylene copolymer is coated on the surface of polyolefin, although the heat resistance and the electrolyte absorption capacity of the diaphragm are enhanced to a certain degree. However, polyvinylidene fluoride and vinylidene fluoride-hexafluoropropylene copolymer have low melting point, so that the heat resistance is not obviously improved, and the polyvinylidene fluoride-hexafluoropropylene copolymer is not suitable for power batteries.
At present, there are reports of patent documents in which a polyolefin microporous film is coated with a heat-resistant polymer such as polyimide, polyetherketone, and aromatic polyamide. CN105336901A provides a preparation method of a high-performance inter-pore coating diaphragm, namely, a high-temperature resistant polymer is prepared into low-concentration oil-based slurry and is applied to a base film in a dip-coating mode, the thickness of the diaphragm is not increased in the mode, the operation is simple, but the composite diaphragm has the defect of powder falling due to poor solubility of the high-temperature resistant polymer in a solvent and poor stability of the oil-based slurry, so that the improvement of the heat resistance is not obvious. CN103531736A prepares heat-resistant fibers such as aromatic polyamide into slurry, and prepares a heat-resistant coating through the steps of coating, pre-pore forming, solidification, water washing and drying, although the fusing temperature of the diaphragm can be higher than 210 ℃ by the method, the method has the disadvantages of complicated steps, long time consumption, no contribution to industrialized rapid large-scale production, and insufficient stability of the slurry.
Disclosure of Invention
In order to overcome the defects of the prior art, the first object of the invention is to provide a polymer coating slurry which is easy to prepare and has good system stability, and a composite diaphragm containing a polymer coating formed by the polymer coating slurry. The polymer coating slurry adopts the auxiliary polymer and the mixed solvent containing the ionic liquid, so that the polymer coating slurry has strong stability, strong adhesive force of the polymer coating and difficult shedding. After the polymer coating slurry which is easy to prepare and good in system stability is prepared, the production of the polymer coating slurry cannot be influenced even if the polymer coating slurry is placed for 72 hours and then used, and the product performance cannot be influenced even if the polymer coating slurry is placed for 48 hours and then used, so that the production and the management are greatly facilitated. And coating the polymer coating slurry on a polyolefin microporous membrane to form a polymer coating, wherein the polymer coating is easy to form and not easy to fall off.
The second purpose of the invention is to provide a preparation method of the composite diaphragm, which is simple and easy to operate, uniform and ordered pore-forming, low in cost and convenient for large-scale production. The composite diaphragm prepared by the method has the characteristics of excellent heat resistance, good wettability of electrolyte and the like. The lithium ion battery prepared by using the composite diaphragm has more excellent safety performance and cycle performance.
The first purpose of the invention is realized by adopting the following technical scheme:
a polymer-coated separator is composed of a polyolefin microporous membrane and a polymer coating layer formed of a polymer coating slurry coated on the polyolefin microporous membrane. The polymer coating slurry is prepared from the following raw materials in parts by mass: 100 parts of main polymer, 10-30 parts of auxiliary polymer, 300-900 parts of mixed solvent, 5-20 parts of pore-foaming agent and 3-10 parts of surfactant. Because the auxiliary polymer and the mixed solvent containing the ionic liquid are adopted, the polymer coating slurry has strong stability, strong adhesive force of the polymer coating and difficult shedding. The polymer coating endows the composite diaphragm with functions of heat resistance, lyophilic and the like, and improves the safety performance and ion permeability of the diaphragm.
Further, the main polymer is one or more of polyacrylonitrile, polyetherimide, polyisophthaloyl metaphenylene diamine, polyethersulfone, polyarylsulfone and a blending and copolymerization system derived from the above polymers.
Further, the weight average molecular weight Mw of the host polymer is 2 × 104≤Mw≤2.4×105And the molecular weight distribution satisfies Mw/Mn of 1.5. ltoreq. Mw/Mn. ltoreq.10, wherein Mn is the number average molecular weight. When the main polymer selected by the invention is in the range, the polymer coating slurry has proper coating viscosity, and the coating has better pore-forming effect and surface density. The weight average molecular weight is too low, and the pore-forming effect is poor; the weight average molecular weight is too high, the weight increase of the coating is large, and the viscosity of the polymer coating liquid is too high, so that the coating uniformity of the coating is not facilitated. The selected polymer has a glass transition temperature or melting point greater than 180 ℃ and a heat resistant operating temperature in excess of 180 ℃ under no load conditions.
Further, the auxiliary polymer is one or more of polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer and polymethyl methacrylate. The auxiliary polymer and the main polymer share the solvent, and the solvent has the properties of cohesiveness and micropore formation, so that the main polymer is prevented from falling off, and the air permeability and porosity of the composite diaphragm are prevented from being seriously reduced. The auxiliary polymer has hydrophilicity for electrolyte and certain gelation capability, so that the diaphragm and the pole piece are attached more tightly, and the liquid injection process of battery assembly is accelerated.
Further, the mixed solvent is a mixed liquid of an organic solvent and an ionic liquid, the mass fraction of the ionic liquid in the mixed solvent is 3% -20%, and the balance is the organic solvent. The mass fraction of the ionic liquid is preferably 5-20%, and more preferably 5-15%. When the mass fraction of the ionic liquid is less than 3%, the mixed solvent cannot fully ensure the stability of the slurry system; if the mass fraction is more than 20%, it is difficult to ensure sufficient subsequent washing to remove the residual mixed solvent. The use of an organic solvent alone is difficult to dissolve the host polymer and to prepare a solution having a high concentration, resulting in a large amount of the organic solvent and difficulty in obtaining a homogeneous stable solution. The invention adopts the mixed solvent of the organic solvent and the ionic liquid, the ionic liquid is used as a green solvent and can dissolve the polymer to a certain degree, and meanwhile, the ionic liquid can be used as a plasticizer of the polymer and has the complexing effect of chemical bonds with the polymer, so that the dissolving capacity of the organic solvent is enhanced, and the ideal coating slurry is more easily obtained.
Further, the organic solvent is one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, acetone and ethanol; the ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate ([ BMIM)]BF4) 1-methyl-3-butylimidazole trifluoroacetate ([ BMIM)]CF3CO2) 1-butyl-3-methylimidazolium chloride ([ BMIM)]Cl), 1-butyl-3-methylimidazolium hexafluorophosphate ([ BMIM)]PF6) 1-vinyl-3-ethylimidazole tetrafluoroborate ([ VEIm)]BF4) 1-Ethyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide salt ([ EMIM)]NTF2) 1-Ethyl-3-methylimidazolium chloroaluminate ([ EMIM ]]AlCl4) 1-benzyl-3-methylimidazolium chloride ([ PhCH)2MIm]Cl), 1-nitrilopropyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide salt ([ CPMIm)]NTf2) One or more combinations thereof.
Further, the pore-foaming agent is one or more of polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol and gamma-butyrolactone. Under the condition that no pore-forming agent is added, part of the coating forms long-strip-shaped finger-shaped macropores in the pore-forming process, so that the mechanical property of the coating is weakened; some of them form a dense structure, which affects the porosity and air permeability of the coating. The pore-forming agent selected by the invention can inhibit the formation of the finger-shaped macropore and the compact structure layer, promote the formation of the cellular or network microporous structure, increase the number of micropores, facilitate the cross-linking and intercommunication between the pores and increase the lyophilic and liquid retention capability of the coating. The pore-forming agent has a pore-forming effect not only on the main polymer but also on the auxiliary polymer.
Under the combined action of the mixed solvent, the pore-forming agent and the surfactant, the polymer coating slurry is stable in system and has certain wettability on a polyolefin microporous membrane, so that the uniformity and the stability of the coating are improved.
Further, the surfactant is one or more of tween 20, tween 40, tween 60, tween 61, tween 80 and tween 85. The surfactant selected by the invention is a nonionic surfactant, which can remarkably change the interface property between a polymer solution and water vapor or coagulation bath liquid, improve the affinity of a solvent and the water vapor or the coagulation bath liquid so as to help the main polymer to form pores and promote the formation of macropores, thereby avoiding the serious blockage of micropores of a base film to greatly reduce the porosity. In addition, the addition of the surfactant can accelerate the phase separation, so that the coating liquid can be rapidly cured on the base film.
The invention also aims to provide a preparation method of the polymer coating diaphragm, which comprises the following steps
Preparation of polymer coating slurry:
adding the main polymer and the auxiliary polymer into the mixed solvent, heating until the main polymer and the auxiliary polymer are stirred and dissolved, adding the pore-foaming agent and the surfactant after the main polymer and the auxiliary polymer are dissolved, continuously heating and stirring until the pore-foaming agent and the surfactant are completely dissolved, and cooling and standing for 0.5-3 h; the heating and stirring temperature is 50-120 ℃;
preparing a composite diaphragm:
and coating the prepared polymer coating slurry on the surface of a polyolefin microporous membrane, forming a hole, cleaning and drying to obtain the composite diaphragm.
Further, the coating mode is one of dip coating, blade coating, slit, micro-concave and reverse roller; the pore-forming process is one of a breathing diagram method and a coagulating bath; the present invention preferably employs a spirogram method. The drying adopts one of natural air drying, hot air drying and high-temperature drying, and the hot air drying is preferentially adopted in the invention, and the drying temperature is 60-80 ℃.
Compared with the prior art, the invention has the beneficial effects that:
(1) the polymer coating slurry has the advantages that the polymer coating slurry has strong stability, strong adhesive force of the polymer coating and difficult shedding due to the adoption of the auxiliary polymer and the mixed solvent containing the ionic liquid; even if the slurry is placed for 72 hours and then used, the production of the slurry is not influenced, and the product performance is not influenced even if the slurry is placed for 48 hours and then used, the polymer coating slurry is easy to prepare and obtain, the system stability is good, and the production and management are greatly facilitated. The polymer coating endows the composite diaphragm with functions of heat resistance, lyophilic and the like, and improves the safety performance and ion permeability of the diaphragm;
(2) the heat-resistant temperature of the main polymer is more than 180 ℃, and the polymer coating is not easy to fall off; therefore, the heat-resistant stability of the diaphragm can be obviously improved, and the safety performance of the lithium ion battery is enhanced. The auxiliary polymer has hydrophilicity to electrolyte and has certain gelation capability, so that the diaphragm and the pole piece are attached more tightly, and the liquid injection process of battery assembly is accelerated. The auxiliary polymer is selected to be used together with the main polymer, and the adhesive property and the property of forming micropores are realized, so that the main polymer is prevented from falling off, and the serious reduction of the air permeability and the porosity of the composite diaphragm can be avoided;
(3) the electrolyte wettability and the electrolyte absorption retention capacity of the composite diaphragm prepared by the invention are improved, so that the lithium ion battery taking the composite diaphragm prepared by the invention as the diaphragm has better cyclic charge-discharge performance and cycle life;
(4) the preparation method of the composite diaphragm provided by the invention is simple and easy to operate, uniform and ordered pore-forming, low in cost and convenient for large-scale production.
Drawings
FIG. 1 is a surface topography photograph of the composite membrane prepared in example 1, magnified 5 thousand times, using a scanning electron microscope;
FIG. 2 is a surface topography photograph of the composite separator prepared in example 1, magnified by 1 ten thousand times, using a scanning electron microscope.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
In the present invention, all parts and percentages are by weight, unless otherwise specified, and the equipment and materials used are commercially available or commonly used in the art. The methods in the following examples are conventional in the art unless otherwise specified.
Example 1
Polymer coating diaphragm prepared by the following method
(1) 10g of a polymer having a weight-average molecular weight Mw of 1.2 × 105Polyetherimide having a molecular weight distribution Mw/Mn of 2 and 1.6g of polyvinylidene fluoride were added to a mixture of 55g N, N-dimethylacetamide and 6.5g of ionic liquid [ BMIM ]]BF4The resulting mixture was dissolved in a solvent mixture at 80 ℃ with stirring. And after the dissolution is finished, adding 1.3g of polyethylene glycol and 0.6g of Tween 80, continuously heating and stirring until the polyethylene glycol and the Tween 80 are completely dissolved, cooling and standing for 1 h.
(2) Coating the prepared coating liquid on two sides of a polyethylene microporous membrane, placing the polyethylene microporous membrane in a constant-temperature and constant-humidity box with the temperature of 60 ℃ and the humidity of 80% for 5min, forming holes by adopting a respiratory diagram method, cleaning the membrane by using deionized water, and finally drying the membrane in hot air at the temperature of 75 ℃ to obtain the composite membrane.
Comparative example 1
The same polyethylene microporous film as in example 1 was used as a comparative example without any treatment.
Example 2
Polymer coating diaphragm prepared by the following method
(1) 10g of a polymer having a weight-average molecular weight Mw of 8 × 104Molecular weight distribution Mw/MnPolyacrylonitrile of 4 and 2g of vinylidene fluoride-hexafluoropropylene copolymer were added to a mixture of 40g N, N-dimethylformamide and 4.5g of ionic liquid [ EMIM ]]AlCl4The resulting mixture was dissolved in a solvent mixture at 70 ℃ with stirring. And after the dissolution is finished, adding 1.5g of polyvinylpyrrolidone and 0.4g of Tween 60, continuously heating and stirring until the polyvinylpyrrolidone and the Tween 60 are completely dissolved, cooling and standing for 1.5 h.
(2) And (3) placing the prepared coating liquid for 24 hours, coating the coating liquid on two sides of a polypropylene microporous membrane, forming pores by adopting a respiration diagram method, namely placing the polypropylene microporous membrane in a constant-temperature and constant-humidity box with the temperature of 65 ℃ and the humidity of 85% for pore formation for 4min, cleaning the polypropylene microporous membrane by using deionized water, and drying the membrane in hot air at the temperature of 80 ℃ to obtain the composite membrane.
Comparative example 2
Except for example 2, the mixed solvent was changed to 40g N, N-dimethylformamide one-component organic solvent, and 1.5g of polyvinylpyrrolidone was not used. The rest is the same as in example 2.
Example 3
Polymer coating diaphragm prepared by the following method
(1) 10g of a polymer having a weight-average molecular weight Mw of 8 × 104Poly (m-phenyleneisophthalamide) with a molecular weight distribution Mw/Mn of 2 and 2g of polyvinylidene fluoride were added to 70g N-methyl pyrrolidone and 6.5g of ionic liquid [ CPMIm ]]NTf2The mixed solvent of (3) is dissolved at 80 ℃ with stirring. And after the dissolution is finished, adding 1g of polyvinylpyrrolidone and 0.5g of Tween 60, continuously heating and stirring until the polyvinylpyrrolidone and the Tween 60 are completely dissolved, cooling and standing for 1 h.
(2) Coating the prepared coating liquid on two sides of a polyethylene microporous membrane, forming pores by adopting a respiration diagram method, namely placing the polyethylene microporous membrane in a constant-temperature constant-humidity box with the temperature of 60 ℃ and the humidity of 80% for 5min, cleaning the polyethylene microporous membrane by using deionized water, and finally drying the membrane in hot air with the temperature of 75 ℃ to obtain the composite membrane.
Comparative example 3
The process was carried out in the same manner as in example 3 except that 2g of polyvinylidene fluoride was not added to example 3.
Example 4
Different from the embodiment 1, the prepared coating solution is coated on both sides of a polyethylene microporous membrane, a coagulating bath is adopted for pore forming, namely, the polyethylene microporous membrane is immersed in a mixed liquid of ethanol and deionized water at 25 ℃ (the volume ratio of the deionized water is 85%), the membrane is washed by the deionized water, and finally the composite membrane is obtained by drying the membrane in hot air at 75 ℃. The rest is the same as in example 1.
Example 5
The difference from example 2 was that in step (2), the standing time was changed from 24 hours to 48 hours, and the rest was the same as in example 2.
Example 6
The difference from example 2 was that in step (2), the standing time was changed from 24 hours to 72 hours, and the rest was the same as in example 2.
Next, the performance of the separators obtained in examples 1 to 6 and comparative examples 1 to 3 was compared.
Table 1 comparison of the properties of the separators in the examples and comparative examples provided by the present invention
The polymer coating slurry system has strong stability, does not influence production and use after being placed for a long time, and is greatly convenient for production and management as can be found by combining the attached drawings 1-2 and the table 1; the polymer coating has good adhesion performance, and the powder falling probability of the coating is greatly reduced; the polymer coating has a microporous structure, and can keep porosity, air permeability and the like without obvious reduction; in addition, the composite diaphragm has obviously enhanced heat-resistant stability, and the wettability and the absorption capacity of the electrolyte are also improved, so that the lithium ion battery using the composite diaphragm provided by the invention has more excellent battery safety performance and cycle performance.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (5)
1. A polymer-coated separator comprising a polyolefin microporous membrane and a polymer coating layer formed of a polymer coating slurry applied to the polyolefin microporous membrane; the polymer coating slurry is prepared from the following raw materials in parts by mass: 100 parts of main polymer, 10-30 parts of auxiliary polymer, 300-900 parts of mixed solvent, 5-20 parts of pore-foaming agent and 3-10 parts of surfactant;
the main polymer is one or more of polyetherimide, polyisophthaloyl metaphenylene diamine, polyether sulfone, polyarylsulfone and a blending and copolymerization system derived from the polymers;
the weight average molecular weight Mw of the host polymer is 2 × 104≤Mw≤2.4×105And the molecular weight distribution satisfies Mw/Mn of 1.5-10, wherein Mn is the number average molecular weight;
the auxiliary polymer is one or more of vinylidene fluoride-hexafluoropropylene copolymer and polymethyl methacrylate;
the mixed solvent is a mixed liquid of an organic solvent and an ionic liquid, the mass fraction of the ionic liquid in the mixed solvent is 3% -20%, and the balance is the organic solvent;
the method comprises the following steps: preparation of polymer coating slurry:
adding the main polymer and the auxiliary polymer into the mixed solvent, heating until the main polymer and the auxiliary polymer are stirred and dissolved, adding the pore-foaming agent and the surfactant after the main polymer and the auxiliary polymer are dissolved, continuously heating and stirring until the pore-foaming agent and the surfactant are completely dissolved, and cooling and standing for 0.5-3 h; the heating and stirring temperature is 50-120 ℃;
preparing a composite diaphragm:
and coating the prepared polymer coating slurry on the surface of a polyolefin microporous membrane, forming a hole, cleaning and drying to obtain the composite diaphragm.
2. The polymer-coated separator according to claim 1, wherein the organic solvent is composed of one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, acetone, and ethanol; the ionic liquid is one or more of 1-butyl-3-methylimidazole tetrafluoroborate, 1-methyl-3-butylimidazole trifluoroacetate, 1-butyl-3-methylimidazole chloride salt, 1-butyl-3-methylimidazole hexafluorophosphate, 1-vinyl-3-ethylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole bis (trifluoromethanesulfonyl) imide salt, 1-ethyl-3-methylimidazole chloroaluminate, 1-benzyl-3-methylimidazole chloride salt and 1-cyanopropyl-3-methylimidazole bis (trifluoromethanesulfonyl) imide salt.
3. The polymer-coated membrane of claim 1, wherein the porogen is comprised of one or more of polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, and gamma-butyrolactone.
4. The polymer-coated membrane of claim 1, wherein the surfactant is comprised of one or more of tween 20, tween 40, tween 60, tween 61, tween 80, and tween 85.
5. The polymer-coated separator of claim 1, wherein the coating means is one of dip coating, knife coating, slit, dimple, and reverse roll; the pore-forming process is one of a breathing diagram method and a coagulating bath; the drying adopts one of natural air drying and high-temperature drying, and the drying temperature is 60-80 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710299391.5A CN107240663B (en) | 2017-05-02 | 2017-05-02 | Polymer coating diaphragm and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710299391.5A CN107240663B (en) | 2017-05-02 | 2017-05-02 | Polymer coating diaphragm and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107240663A CN107240663A (en) | 2017-10-10 |
| CN107240663B true CN107240663B (en) | 2020-08-28 |
Family
ID=59984244
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710299391.5A Active CN107240663B (en) | 2017-05-02 | 2017-05-02 | Polymer coating diaphragm and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107240663B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108486687B (en) * | 2018-02-28 | 2020-10-27 | 海信（山东）空调有限公司 | Moisture-absorbing coating material, preparation method and application thereof |
| KR102592147B1 (en) * | 2018-04-20 | 2023-10-23 | 삼성전자주식회사 | Composite separator, preparing method thereof, and lithium secondary battery including the same |
| CN108807802A (en) * | 2018-08-20 | 2018-11-13 | 湖南烁普新材料有限公司 | Highly-breathable polymer-coated diaphragm and its preparation method and application |
| CN109244322B (en) * | 2018-09-18 | 2021-10-22 | 武汉惠强新能源材料科技有限公司 | Water-based coating for lithium ion battery diaphragm and preparation method and application thereof |
| CN109301134A (en) * | 2018-10-31 | 2019-02-01 | 河北金力新能源科技股份有限公司 | Diaphragm coating paste and preparation method thereof, lithium ion battery separator and preparation method thereof and lithium ion battery |
| CN109537301A (en) * | 2018-11-26 | 2019-03-29 | 蚌埠星烁新材料科技有限公司 | A method of synthetic leather functional coating is prepared with solution casting method final finishing technology |
| CN110112352A (en) * | 2019-06-17 | 2019-08-09 | 合肥国轩高科动力能源有限公司 | A kind of polyimide diaphragm and its preparation method and application |
| CN110635090B (en) * | 2019-09-27 | 2022-04-29 | 宁德卓高新材料科技有限公司 | Preparation method of high-heat-resistance vinylidene fluoride polymer mixed coating diaphragm |
| CN112321860A (en) * | 2020-10-29 | 2021-02-05 | 深圳市华科创智技术有限公司 | Preparation method of bending-resistant microporous film and prepared microporous film |
| CN113708008A (en) * | 2021-07-29 | 2021-11-26 | 惠州锂威新能源科技有限公司 | Isolating membrane and preparation method and application thereof |
| CN113937417B (en) * | 2021-10-27 | 2022-08-02 | 长园泽晖新能源材料研究院(珠海)有限公司 | Photocuring modified lithium ion battery diaphragm and preparation method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102306727A (en) * | 2011-08-12 | 2012-01-04 | 沧州明珠塑料股份有限公司 | Polymer modification polyolefin lithium ion battery membrane and preparation method thereof |
| CN202549958U (en) * | 2011-10-31 | 2012-11-21 | 广州丰江电池新技术股份有限公司 | Double-membrane lithium ion battery |
| CN102792487A (en) * | 2010-03-15 | 2012-11-21 | 锂电池科技有限公司 | Lithium ion cell having intrinsic protection against thermal runaway |
| CN103915595A (en) * | 2014-04-23 | 2014-07-09 | 深圳市星源材质科技股份有限公司 | Aqueous polymer diaphragm and preparation method thereof |
| CN104143615A (en) * | 2013-08-26 | 2014-11-12 | 河南师范大学 | Lithium ion battery composite diaphragm and preparation method thereof |
| CN104321922A (en) * | 2012-04-23 | 2015-01-28 | 索尔维公司 | Fluoropolymer film |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101117126B1 (en) * | 2010-04-19 | 2012-02-24 | 한국과학기술연구원 | Metal oxide ultrafine fiber-based composite separator with heat resistance and secondary battery using same |
| JP2013069517A (en) * | 2011-09-22 | 2013-04-18 | Shin Etsu Chem Co Ltd | Negative electrode paste, negative electrode and method for manufacturing the same, and nonaqueous electrolyte secondary battery |
| KR101792749B1 (en) * | 2013-06-19 | 2017-10-31 | 주식회사 엘지화학 | Tri-layered separator for secondary battery, secondary battery comprising the same, and method of preparing the separator |
| CN103531736B (en) * | 2013-10-27 | 2016-08-24 | 乐凯胶片股份有限公司 | A kind of high heat-resisting lithium ion battery separator and preparation method thereof |
| TWI526484B (en) * | 2013-10-31 | 2016-03-21 | Ｌｇ化學股份有限公司 | Porous separator having inverse opal structure for secondary battery and method for manufacturing the same |
| CN105336901B (en) * | 2015-09-25 | 2017-10-13 | 深圳市星源材质科技股份有限公司 | The preparation method of barrier film is coated between a kind of high-performance hole |
| CA3001521C (en) * | 2015-10-19 | 2023-10-03 | Solvay Specialty Polymers Italy S.P.A. | Coated battery separator |
-
2017
- 2017-05-02 CN CN201710299391.5A patent/CN107240663B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102792487A (en) * | 2010-03-15 | 2012-11-21 | 锂电池科技有限公司 | Lithium ion cell having intrinsic protection against thermal runaway |
| CN102306727A (en) * | 2011-08-12 | 2012-01-04 | 沧州明珠塑料股份有限公司 | Polymer modification polyolefin lithium ion battery membrane and preparation method thereof |
| CN202549958U (en) * | 2011-10-31 | 2012-11-21 | 广州丰江电池新技术股份有限公司 | Double-membrane lithium ion battery |
| CN104321922A (en) * | 2012-04-23 | 2015-01-28 | 索尔维公司 | Fluoropolymer film |
| CN104143615A (en) * | 2013-08-26 | 2014-11-12 | 河南师范大学 | Lithium ion battery composite diaphragm and preparation method thereof |
| CN103915595A (en) * | 2014-04-23 | 2014-07-09 | 深圳市星源材质科技股份有限公司 | Aqueous polymer diaphragm and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107240663A (en) | 2017-10-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107240663B (en) | Polymer coating diaphragm and preparation method thereof | |
| CN108346765B (en) | Composite lithium ion battery diaphragm and preparation method thereof | |
| Li et al. | Effects of an electrospun fluorinated poly (ether ether ketone) separator on the enhanced safety and electrochemical properties of lithium ion batteries | |
| CN107170942B (en) | High-temperature-resistant aramid fiber lithium ion battery composite diaphragm and preparation method thereof | |
| JP5524330B2 (en) | Polymer composite electrolyte, battery containing polymer composite electrolyte, and method for preparing the same | |
| Kang et al. | A thermostability gel polymer electrolyte with electrospun nanofiber separator of organic F-doped poly-m-phenyleneisophthalamide for lithium-ion battery | |
| CN107958977B (en) | Battery diaphragm, lithium ion battery and preparation method thereof | |
| Yang et al. | Design of block‐copolymer nanoporous membranes for robust and safer lithium‐ion battery separators | |
| CN109817865B (en) | Composite diaphragm and preparation method thereof | |
| CN107195838B (en) | Heat-resistant coating with uniform and ordered pore diameter for lithium ion battery diaphragm and preparation method thereof | |
| KR102432479B1 (en) | Polymer electrolyte membrane and manufacturing method thereof | |
| WO2017133375A1 (en) | Method for preparing aromatic polyamide porous film and aromatic polyamide porous film | |
| CN102015083A (en) | Microporous polyolefin composite film with a thermally stable porous layer at high temperature | |
| CN105552278A (en) | Preparation method of polyamide-imide lithium battery membrane | |
| CN111370625A (en) | Aramid fiber phase-transition coating lithium ion battery diaphragm and preparation method thereof | |
| CN108807818B (en) | Aromatic polyamide composite diaphragm and preparation method thereof | |
| CN112086611B (en) | Composite diaphragm and preparation method and application thereof | |
| Niu et al. | Evidence of high temperature stable performance of polyether ether ketone (PEEK) separator with sponge-structured in lithium-ion battery | |
| CN114122619A (en) | Lithium battery diaphragm and preparation method thereof | |
| CN113381122A (en) | Method for preparing porous meta-aramid diaphragm by non-solvent induced phase separation method | |
| JP3942277B2 (en) | Composite polymer electrolyte membrane and method for producing the same | |
| KR101296109B1 (en) | Menufacturing Method of Meta-Aramid Based Porous Membrane for Secondary Battery and Porous Membrane thereby | |
| KR20160032311A (en) | Battery Separator with Excellent Shut-down Function and Heat Resistance and Secondaty Cell Battery | |
| CN114709558A (en) | High-heat-resistance polyamide-imide composite diaphragm and preparation method thereof | |
| KR101377476B1 (en) | Menufacturing Method of Meta-Aramid Based Porous Membrane for Secondary Battery and Porous Membrane thereby |
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 |
Address after: 528000 Guangdong, Foshan, Chancheng, Ji Hua Road 28, a two 17 story (residence declaration) Applicant after: Foshan Jinhui Gao Ke photoelectric material Limited by Share Ltd. Address before: 528000 light industrial No. three, Chancheng District, Foshan, Guangdong Province, No. 7 Applicant before: FOSHAN JINHUI HIGH-TECH OPTOELECTRONIC MATERIAL Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220719 Address after: 518000 c401-2, No.4 workshop, park, Yingzhan Electronic Technology (Shenzhen) Co., Ltd., Longtian community, Longtian street, Pingshan District, Shenzhen City, Guangdong Province Patentee after: Shenzhen dingtaixiang New Energy Technology Co.,Ltd. Address before: 528000 Guangdong, Foshan, Chancheng, Ji Hua Road 28, a two 17 story (residence declaration) Patentee before: Foshan Jinhui Gao Ke photoelectric material Limited by Share Ltd. |
|
| TR01 | Transfer of patent right |