CN111816823A - Thermal self-closing ceramic modified diaphragm and preparation method thereof - Google Patents
Thermal self-closing ceramic modified diaphragm and preparation method thereof Download PDFInfo
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- 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
-
- 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
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The invention discloses a thermal self-closing ceramic modified diaphragm and a preparation method thereof, belonging to the technical field of lithium battery diaphragms. The preparation method of the thermal self-closing ceramic modified diaphragm comprises the following steps: s1: preparing a thermal self-closing ceramic coating, S2: unwinding polyolefin membrane substrate, S3: and (3) carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate, and coating the thermal self-closing ceramic coating prepared in the step S1 after the corona treatment is finished, wherein the step S4: and (3) drying and shaping the coated polyolefin diaphragm base material, wherein S5: the thermal self-closing ceramic modified diaphragm and the preparation method thereof have the advantages that the thermal self-closing ceramic modified diaphragm has thermal self-closing performance, improves safety, has thermosetting property and improves the diaphragm breaking temperature.
Description
Technical Field
The invention belongs to the technical field of lithium battery diaphragms, and particularly relates to a thermal self-closing ceramic modified diaphragm and a preparation method thereof.
Background
The lithium ion battery is an energy storage system with the advantages of high energy density, high output voltage, no memory effect, excellent cycle performance, environmental friendliness and the like, has good economic and social benefits and strategic significance, is widely applied to various fields such as mobile communication, digital products and the like, and also becomes one of the most main power supply systems in the fields of energy storage and electric automobiles.
The ceramic diaphragm is mainly used for isolating the positive electrode and the negative electrode of the high-power lithium ion battery, can isolate the contact between the positive electrode and the negative electrode of the battery, does not prevent electrolyte in the battery from permeating the diaphragm, and can prevent the occurrence of explosion and the like caused by short circuit. Polyolefin diaphragm materials with a microporous structure, such as single-layer or multi-layer films of Polyethylene (PE) and Polypropylene (PP), are mainly used in current commercial lithium ion batteries. Although the polyolefin diaphragm can provide enough mechanical strength and chemical stability at normal temperature due to the characteristics of the polymer, the polyolefin diaphragm shows larger thermal shrinkage at high temperature, so that the anode and the cathode of the battery are contacted and a large amount of heat is rapidly accumulated, although the PP/PE composite diaphragm can firstly melt PE at lower temperature (120 ℃) to block micropores in the polymer and block ion conduction, and PP still plays a role in supporting to prevent further electrode reaction, the melting temperature of PP is only 150 ℃, and when the temperature rapidly rises and exceeds the melting temperature of PP, the melting of the diaphragm can cause large-area short circuit and cause heat to be out of control, heat accumulation is intensified, high air pressure and high temperature in the battery are generated, and the combustion or explosion of the battery is caused. The internal short circuit of the battery is the biggest hidden trouble of the safety of the lithium ion battery. In order to meet the development requirement of a large-capacity lithium ion battery, the development of a high-safety diaphragm becomes a first priority of the industry, and the excellent temperature resistance and high safety of the ceramic diaphragm make the ceramic diaphragm become one of the primary choices for replacing the traditional polyolefin diaphragm.
Ceramic diaphragms (Ceramic-coated Separators) are formed by coating and compounding a uniform protective layer (several micrometers) composed of Ceramic microparticles and the like on one side or two sides of the surface of the existing polyolefin microporous membrane to form a porous safety functional diaphragm. On the basis of ensuring the original basic characteristics of the polyolefin microporous diaphragm, the diaphragm is endowed with higher heat resistance, and the heat shrinkage of the diaphragm is reduced, so that the internal short circuit of the lithium ion battery is effectively avoided, and the thermal runaway of the battery which is weak due to the internal short circuit of the battery is prevented. At present, ceramic diaphragms are mainly prepared by dispersing ceramic powder (mainly nano or sub-nano oxide powder such as aluminum oxide, titanium dioxide, silicon dioxide and the like), a binder and the like in a solvent to form slurry, and then forming a ceramic coating on the surface of a polyolefin diaphragm by a casting method or a dipping method (for example, chinese patent CN 103579564B). However, since the specific surface energy of the ceramic powder is large, the ceramic powder is easy to agglomerate, the surface is generally hydrophilic, and the polyolefin film is a hydrophobic material, research reports show that the uniformity of the ceramic powder coating is poor, and an obvious powder falling phenomenon exists, which can greatly influence the service performance of the ceramic diaphragm in the lithium ion battery.
Disclosure of Invention
The invention aims to provide a thermal self-closing ceramic modified diaphragm and a preparation method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a thermal self-closing ceramic modified diaphragm which comprises a polyolefin diaphragm base material, wherein at least one surface of the polyolefin diaphragm base material is subjected to corona treatment to form a corona treatment surface, and a thermal self-closing ceramic coating is coated on the corona treatment surface. The thermal self-closing ceramic coating can be coated on the polyolefin diaphragm substrate on a single surface or can be coated on the polyolefin diaphragm substrate on two surfaces.
Preferably, the thermal self-closing ceramic coating comprises the following components in percentage by weight: 1 to 52 percent of ceramic particle premix, 0.5 to 10 percent of thermosetting oligomer, 0.01 to 0.2 percent of superfine microsphere foaming body, 1 to 15 percent of flatting agent and 18 to 97.49 percent of macromolecule emulsion.
Preferably, in the thermal self-closing ceramic coating, the ceramic particle premix is 10-25%, the thermocurable oligomer is 1-3%, the superfine microsphere foaming body is 0.01-0.05%, the leveling agent is 2-5%, and the polymer emulsion is 68-88%.
Preferably, the ceramic particle premix comprises tetraethoxysilane, nano-alumina and nano-titanium dioxide in a weight ratio of 2 (0.8-1.2) to (0.8-1.2). The pre-mixture of ceramic particles is primarily used to improve the thermal insulation properties of the separator, and when the temperature is raised above 140 ℃, the ceramic particles are effective to prevent lithium ions from passing through the separator and further shorting and causing a temperature rise.
Preferably, the ceramic particle premix further comprises 0.45 to 0.58% by weight of the ceramic particle premix of a titanate coupling agent as a dispersion stabilizer. The titanate coupling agent can help the ceramic particle premix to be dispersed and the slurry to be uniform and stable.
Preferably, the heat-curable oligomer is one of novolac epoxy acrylic resin, epoxy acrylic resin and dual-curing oligomer. Wherein the dual cure oligomer is LR9000 from Pasteur or UVDC-2700 from Doxon chemical industry, Shanghai. The thermally curable oligomer is more preferably a novolac epoxy acrylic resin or an epoxy acrylic resin. The thermocurable oligomer is used for further improving the heat resistance of the diaphragm, and can be subjected to thermocuring polymerization after the temperature is increased to more than 120 ℃ so as to prevent the diaphragm from being further melted, thereby improving the temperature resistance of the diaphragm.
Preferably, the ultrafine microsphere foam is a physical foaming agent or a chemical foaming agent, and the physical foaming agent is one of calcium carbonate, magnesium carbonate, sodium bicarbonate, n-hexane, petroleum ether, trichlorofluoromethane and dichlorotetrafluoroethane.
Preferably, the particle size of the sodium bicarbonate is 0.5-2 μm. The superfine sodium bicarbonate has small pore diameter and belongs to a heat absorption type foaming agent. The foaming temperature (decomposition temperature) is 110-160 ℃, a very small amount of superfine sodium bicarbonate closed-cell foaming agent is added into the ceramic diaphragm, and when the temperature of the ceramic diaphragm is increased to the foaming temperature (decomposition temperature) during use, the sodium bicarbonate absorbs heat during decomposition, so that the temperature increase can be slowed down; when the using amount is controlled to be below 0.05%, the volume increase generated by foaming is just equivalent to the volume of the shrinkage of the diaphragm due to high temperature, and the micropores generated by foaming prevent the shrinkage of the diaphragm from causing the puncture of the diaphragm, so that the film breaking temperature of the diaphragm is improved.
Preferably, the leveling agent is one of polyether polyester modified organic siloxane, alkyl modified organic siloxane, organic silicon modified polysiloxane acrylic acid, acrylic resin, urea resin or melamine formaldehyde resin. More preferably an acrylic resin.
Preferably, the polymer emulsion is one of acrylic resin emulsion, polyurethane emulsion, silicone-acrylic emulsion, polyvinyl acetate emulsion and styrene-acrylic emulsion. More preferably an acrylic resin emulsion or a polyurethane emulsion.
Preferably, the polyolefin separator substrate is one of a polyethylene porous film (single-layer or multi-layer composite film), a polypropylene porous film (single-layer or multi-layer composite film), a polyethylene non-woven fabric or a polypropylene non-woven fabric, and has a thickness of 10 to 80 μm. More preferably 15-35 μm.
Preferably, when only one side of the thermal self-closing ceramic modified diaphragm is provided with the thermal self-closing ceramic coating, the thickness of the thermal self-closing ceramic coating is 2-30 μm, more preferably 5-15 μm, and when both sides of the thermal self-closing ceramic modified diaphragm are provided with the thermal self-closing ceramic coating, the thickness of the thermal self-closing ceramic coating is consistent and is 1-10 μm, more preferably 3-10 μm.
The invention also provides a preparation method of the thermal self-closing ceramic modified diaphragm, which comprises the following steps: s1: preparing a thermal self-closing ceramic coating, S2: unwinding polyolefin membrane substrate, S3: and (3) carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate, and coating the thermal self-closing ceramic coating prepared in the step S1 after the corona treatment is finished, wherein the step S4: and (3) drying and shaping the coated polyolefin diaphragm base material, wherein S5: and (4) after drying, rolling and placing at normal temperature for curing for 6-8 days to obtain the thermal self-closing ceramic modified diaphragm.
Preferably, the specific steps of step S1 are as follows: s10, preparing a ceramic particle premix, preparing tetraethoxysilane, nano-alumina and nano-titanium dioxide according to the weight ratio of 2 (0.8-1.2), adding a titanate coupling agent accounting for 0.45-0.58% of the weight of the ceramic particle premix, dispersing at a high speed of more than 120rpm by using a stirrer, stirring the dispersed ceramic particle premix for 20-30min, standing for defoaming, and S20, adding a thermocurable oligomer, an ultrafine microsphere foaming body, a leveling agent and a high polymer emulsion, and stirring to prepare the thermal self-closing ceramic coating.
Preferably, in step S4, the drying and shaping are performed by hot air flotation, wherein the drying temperature is 50-60 ℃.
The invention has the beneficial effects that:
1. the lithium ion battery has thermal self-closing performance, prevents lithium ions from penetrating through the diaphragm, avoids temperature rise caused by further short circuit, and improves safety.
2. Has thermosetting property and can raise film-breaking temperature.
3. The thermal self-closing ceramic coating has good adhesive force with the polyolefin diaphragm base material, and avoids easy 'powder falling' of the diaphragm.
4. The raw materials are easy to purchase and the cost is low.
5. The process technology is mature, and the mass industrial production is easy to realize.
Drawings
FIG. 1 is a schematic diagram of a first structure of the thermal self-closing ceramic modified diaphragm (single-side coated thermal self-closing ceramic coating).
FIG. 2 is a schematic diagram of a second structure of the thermal self-closing ceramic modified diaphragm (double-sided coated thermal self-closing ceramic coating) of the invention.
The labels in the figures are: 1-polyolefin diaphragm base material, 2-corona treatment surface and 3-thermal self-closing ceramic coating.
Detailed Description
The following detailed description of embodiments of the invention is intended to be illustrative of the invention and is not to be construed as limiting the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.
The first embodiment is as follows:
the preparation method of the self-closing ceramic modified diaphragm provided by the embodiment comprises the following steps:
s1: preparing a thermal self-closing ceramic coating 3, specifically, firstly preparing a ceramic particle premix, adding 0.995kg of tetraethoxysilane, 0.4975kg of nano alumina and 0.4975kg of nano titanium dioxide, adding 0.01kg of titanate coupling agent, carrying out high-speed dispersion by using a stirrer at the rotating speed of 130rpm, stirring the dispersed ceramic particle premix for 25min, and standing for defoaming. Then 0.2kg of novolac epoxy acrylic resin, 0.003kg of superfine sodium bicarbonate, 0.5kg of acrylic resin and 7.297kg of acrylic resin emulsion are respectively added and stirred to prepare 10kg of thermal self-closing ceramic coating 3.
S2: unreeling a polyolefin diaphragm substrate 1.
S3: and (3) carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate 1 to form a corona treated surface 2, and coating the thermal self-closing ceramic coating 3 prepared in the step S1 after the corona treatment is finished. Specifically, when single-sided coating is performed, corona treatment is performed on the coated side, and then the thermal self-closing ceramic coating 3 is applied. When double-sided coating is performed, corona treatment is performed on one side to be coated, then the thermal self-closing ceramic coating 3 is applied to the one side, then corona treatment is performed on the other side to be coated, and then the thermal self-closing ceramic coating 3 is applied to the one side.
S4: and drying and shaping the coated polyolefin diaphragm substrate 1 by adopting hot air flotation, wherein the drying temperature is 55 ℃.
S5: and (3) after drying, rolling and placing at normal temperature for curing for 7 days to obtain the thermal self-closing ceramic modified diaphragm, wherein one side is shown in figure 1, and the two sides are shown in figure 2.
Example two:
the preparation method of the self-closing ceramic modified diaphragm provided by the embodiment comprises the following steps:
s1: preparing a thermal self-closing ceramic coating 3, specifically, firstly preparing a ceramic particle premix, adding 1.14425kg of tetraethoxysilane, 0.572125kg of nano alumina and 0.572125kg of nano titanium dioxide, adding 0.0115kg of titanate coupling agent, dispersing at a high speed by a stirrer at the rotating speed of 135rpm, stirring the dispersed ceramic particle premix for 30min, standing and defoaming. Then 0.3kg of novolac epoxy acrylic resin, 0.001kg of superfine sodium bicarbonate, 0.2kg of acrylic resin and 7.199kg of polyurethane emulsion are respectively added and stirred to prepare 10kg of thermal self-closing ceramic coating.
S2: unreeling a polyolefin diaphragm substrate 1.
S3: and (3) carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate 1 to form a corona treated surface 2, and coating the thermal self-closing ceramic coating 3 prepared in the step S1 after the corona treatment is finished. Specifically, when single-sided coating is performed, corona treatment is performed on the coated side, and then the thermal self-closing ceramic coating 3 is applied. When double-sided coating is performed, corona treatment is performed on one side to be coated, then the thermal self-closing ceramic coating 3 is applied to the one side, then corona treatment is performed on the other side to be coated, and then the thermal self-closing ceramic coating 3 is applied to the one side.
S4: and drying and shaping the coated polyolefin diaphragm substrate 1 by adopting hot air flotation, wherein the drying temperature is 60 ℃.
S5: and (4) after drying, rolling and placing at normal temperature for curing for 8 days to obtain the thermal self-closing ceramic modified diaphragm.
Example three:
the preparation method of the self-closing ceramic modified diaphragm provided by the embodiment comprises the following steps:
s1: preparing a thermal self-closing ceramic coating 3, specifically, firstly preparing a ceramic particle premix, adding 0.74625kg of tetraethoxysilane, 0.373125kg of nano alumina and 0.373125kg of nano titanium dioxide, adding 0.0075kg of titanate coupling agent, dispersing at a high speed by a stirrer at the rotating speed of 125rpm, stirring the dispersed ceramic particle premix for 20min, and standing for defoaming. Then respectively adding 0.1kg of epoxy acrylic resin, 0.002kg of superfine sodium bicarbonate, 0.3kg of acrylic resin and 8.098kg of acrylic resin emulsion, and stirring to prepare 10kg of thermal self-closing ceramic coating.
S2: unreeling a polyolefin diaphragm substrate 1.
S3: and (3) carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate 1 to form a corona treated surface 2, and coating the thermal self-closing ceramic coating 3 prepared in the step S1 after the corona treatment is finished. Specifically, when single-sided coating is performed, corona treatment is performed on the coated side, and then the thermal self-closing ceramic coating 3 is applied. When double-sided coating is performed, corona treatment is performed on one side to be coated, then the thermal self-closing ceramic coating 3 is applied to the one side, then corona treatment is performed on the other side to be coated, and then the thermal self-closing ceramic coating 3 is applied to the one side.
S4: and drying and shaping the coated polyolefin diaphragm substrate 1 by adopting hot air flotation, wherein the drying temperature is 50 ℃.
S5: and (4) after drying, rolling and placing at normal temperature for curing for 6 days to obtain the thermal self-closing ceramic modified diaphragm.
The invention mainly utilizes the comprehensive effects of the thermal stability of ceramics, the thermosetting property of oligomer and the superfine microsphere foaming body to ensure that the diaphragm starts to foam after the temperature is increased to be more than 110 ℃ to prevent the contraction of the diaphragm and the thermosetting property of the oligomer from preventing the melting of the diaphragm, thereby leading the diaphragm to generate thermal self-closing property to improve the film breaking temperature; by adopting a corona treatment process technology, the adhesive force of the ceramic coating and the polyolefin diaphragm base material 1 is improved, and the diaphragm is prevented from easily falling off.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art; the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A thermal self-closing ceramic modified diaphragm is characterized in that,
comprising a polyolefin separator substrate;
at least one surface of the polyolefin diaphragm base material is subjected to corona treatment to form a corona treatment surface;
and a thermal self-closing ceramic coating is coated on the corona treatment surface.
2. The thermally self-closing ceramic modified membrane of claim 1,
the thermal self-closing ceramic coating comprises the following components in percentage by weight:
1-52% of ceramic particle premix;
0.5-10% of a heat-curable oligomer;
0.01 to 0.2 percent of superfine microsphere foaming body;
1-15% of a leveling agent;
18-97.49% of polymer emulsion.
3. The thermally self-closing ceramic modified membrane of claim 2,
the ceramic particle premix comprises tetraethoxysilane, nano-alumina and nano-titanium dioxide, and the weight ratio of the tetraethoxysilane to the nano-alumina to the nano-titanium dioxide is 2 (0.8-1.2) to 0.8-1.2.
4. The thermally self-closing ceramic modified membrane according to claim 2 or 3,
the ceramic particle premix also includes a titanate coupling agent as a dispersion stabilizer in an amount of 0.45 to 0.58% by weight of the ceramic particle premix.
5. The thermally self-closing ceramic modified membrane of claim 1,
the thermosetting oligomer is one of novolac epoxy acrylic resin, epoxy acrylic resin and dual-curing oligomer;
the superfine microsphere foaming body is a physical foaming agent or a chemical foaming agent;
the physical foaming agent is one of calcium carbonate, magnesium carbonate, sodium bicarbonate, n-hexane, petroleum ether, trichlorofluoromethane and dichlorotetrafluoroethane;
the leveling agent is one of polyether polyester modified organic siloxane, alkyl modified organic siloxane, organic silicon modified polysiloxane acrylic acid, acrylic resin, urea resin or melamine formaldehyde resin;
the high polymer emulsion is one of acrylic resin emulsion, polyurethane emulsion, silicone-acrylic emulsion, polyvinyl acetate emulsion and styrene-acrylic emulsion;
the polyolefin diaphragm base material is one of a polyethylene porous membrane, a polypropylene porous membrane, a polyethylene non-woven fabric or a polypropylene non-woven fabric, and the thickness of the polyolefin diaphragm base material is 10-80 mu m.
6. The thermally self-closing ceramic modified membrane of claim 5,
the particle size of the sodium bicarbonate is 0.5-2 μm.
7. The thermally self-closing ceramic modified membrane of claim 1,
when only one surface of the thermal self-closing ceramic modified diaphragm is provided with the thermal self-closing ceramic coating, the thickness of the thermal self-closing ceramic coating is 2-30 mu m;
when the thermal self-closing ceramic modified diaphragm is provided with the thermal self-closing ceramic coating on both sides, the thickness of the thermal self-closing ceramic coating is consistent and is 1-10 mu m.
8. The preparation method of the thermal self-closing ceramic modified diaphragm is characterized by comprising the following steps:
s1: preparing a thermal self-closing ceramic coating;
s2: unreeling a polyolefin diaphragm substrate;
s3: carrying out corona treatment on the coated surface of the polyolefin diaphragm substrate, and coating the thermal self-closing ceramic coating prepared in the step S1 after the corona treatment is finished;
s4: drying and shaping the coated polyolefin diaphragm base material;
s5: and (4) after drying, rolling and placing at normal temperature for curing for 6-8 days to obtain the thermal self-closing ceramic modified diaphragm.
9. The thermally self-closing ceramic modified membrane of claim 8,
the specific steps of step S1 are as follows:
s10, preparing a ceramic particle premix, preparing tetraethoxysilane, nano-alumina and nano-titanium dioxide according to the weight ratio of 2 (0.8-1.2) to 0.8-1.2, adding a titanate coupling agent accounting for 0.45-0.58 percent of the weight of the ceramic particle premix, dispersing at a high speed by a stirrer at a rotating speed of more than 120rpm, stirring the dispersed ceramic particle premix for 20-30min, standing and defoaming;
and S20, adding the low polymer which can be thermally cured, the superfine microsphere foaming body, the flatting agent and the high polymer emulsion, and stirring to prepare the thermal self-closing ceramic coating.
10. The thermally self-closing ceramic modified membrane of claim 9,
in the step S4, the drying and shaping are carried out by hot air flotation, and the drying temperature is 50-60 ℃.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112290163A (en) * | 2020-10-30 | 2021-01-29 | 广东宝路盛精密机械有限公司 | Modified three-layer co-extrusion diaphragm of lithium-sulfur battery and preparation method and application thereof |
| CN115491737A (en) * | 2022-09-14 | 2022-12-20 | 暨南大学 | Method for dispersing ceramic particles in metal ceramic composite plating solution |
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| CN105140451A (en) * | 2015-07-06 | 2015-12-09 | 佛山荷韵特种材料有限公司 | Lithium-ion battery diaphragm and preparation method thereof |
| CN111244362A (en) * | 2020-01-15 | 2020-06-05 | 惠州锂威新能源科技有限公司 | Composite diaphragm, preparation method thereof and lithium ion battery |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105140451A (en) * | 2015-07-06 | 2015-12-09 | 佛山荷韵特种材料有限公司 | Lithium-ion battery diaphragm and preparation method thereof |
| CN111244362A (en) * | 2020-01-15 | 2020-06-05 | 惠州锂威新能源科技有限公司 | Composite diaphragm, preparation method thereof and lithium ion battery |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112290163A (en) * | 2020-10-30 | 2021-01-29 | 广东宝路盛精密机械有限公司 | Modified three-layer co-extrusion diaphragm of lithium-sulfur battery and preparation method and application thereof |
| CN115491737A (en) * | 2022-09-14 | 2022-12-20 | 暨南大学 | Method for dispersing ceramic particles in metal ceramic composite plating solution |
| CN115491737B (en) * | 2022-09-14 | 2023-09-29 | 暨南大学 | Method for dispersing ceramic particles in metal ceramic composite plating solution |
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Application publication date: 20201023 |