CN111342120A - Polymer solid electrolyte, nano composite diaphragm and preparation method thereof, and lithium metal battery - Google Patents
Polymer solid electrolyte, nano composite diaphragm and preparation method thereof, and lithium metal battery Download PDFInfo
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- CN111342120A CN111342120A CN201911287044.6A CN201911287044A CN111342120A CN 111342120 A CN111342120 A CN 111342120A CN 201911287044 A CN201911287044 A CN 201911287044A CN 111342120 A CN111342120 A CN 111342120A
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- 239000007784 solid electrolyte Substances 0.000 title claims abstract description 66
- 239000002114 nanocomposite Substances 0.000 title claims abstract description 50
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- 238000002360 preparation method Methods 0.000 title claims description 15
- PEDCQBHIVMGVHV-UHFFFAOYSA-N glycerol group Chemical group OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims abstract description 95
- 239000002033 PVDF binder Substances 0.000 claims abstract description 78
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims abstract description 75
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 62
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- 239000000377 silicon dioxide Substances 0.000 claims abstract description 61
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- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 46
- 229910052593 corundum Inorganic materials 0.000 claims abstract description 46
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- 239000007788 liquid Substances 0.000 claims description 37
- 235000011187 glycerol Nutrition 0.000 claims description 31
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- SECXISVLQFMRJM-UHFFFAOYSA-N NMP Substances CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 27
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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
-
- 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
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/403—Manufacturing processes of separators, membranes or diaphragms
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- 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
- H01M50/46—Separators, membranes or diaphragms characterised by their combination with electrodes
- H01M50/461—Separators, membranes or diaphragms characterised by their combination with electrodes with adhesive layers between electrodes and separators
-
- 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)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Dispersion Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Inorganic Chemistry (AREA)
- Cell Separators (AREA)
- Secondary Cells (AREA)
Abstract
The invention relates to a polymer solid electrolyte, which comprises a film-forming agent, a lithium ion conductor, a reinforcing agent, a cross-linking agent and a solvent; the film forming agent is any two of PU, Nafion or PVDF; the lithium ion conductor is SiO2Or ZnO; the reinforcing agent is Al2O3Or LiCl; the cross-linking agent is glycerol; the solvent is NMP, DMF or CHCl3Any one of them. A nanocomposite separator includes a porous substrate, and a polymer solid electrolyte filled or coated inside and on the surface of the porous substrate and dried. A process for preparing the nano-composite membrane includes filling or coating the solid polymer electrolyte in the porous matrix and dryingAnd drying to obtain the nano composite diaphragm. A lithium metal battery includes a nanocomposite separator. Can effectively inhibit the generated lithium dendrite from puncturing the diaphragm to cause short circuit thermal runaway and even explosion of the battery.
Description
Technical Field
The invention relates to the technical field of lithium metal batteries, in particular to a polymer solid electrolyte, a nano composite diaphragm, a preparation method of the nano composite diaphragm and a lithium metal battery.
Background
With the progress of science and technology and the continuous development of economy, the life of people is greatly improved, but meanwhile, the problems of energy and environment are increasingly aggravated, and the important development trend of energy conservation, emission reduction, new energy development and efficient energy conversion devices in the current society is. In the last two decades, secondary batteries such as lithium ion batteries using graphite as a negative electrode have been developed greatly and are widely used in the fields of portable electronic products, electric automobiles and the like. However, the energy density of the lithium ion battery using graphite as the negative electrode is gradually close to the theoretical value, and the requirements of the current energy storage market on gradual expansion and the endurance of the electric vehicle cannot be met.
Metallic lithium has low density, low potential, good electronic conductivity and high electrochemical equivalent, the theoretical capacity can reach 3800mAh/g, which is 10 times of that of the current graphite cathode, so researchers have paid attention to lithium metal batteries such as lithium-sulfur batteries and lithium-air batteries which use metallic lithium as a cathode, however, the use of metallic lithium as a cathode still faces a lot of great challenges, such as corrosion of metallic lithium of the cathode due to a small amount of oxygen, carbon dioxide, water and the like permeating through a diaphragm, and shortening of the cycle life of lithium; in the charging/discharging process, because the local current density is overlarge, the deposition/dissolution of lithium ions is uneven, and lithium dendrites are generated to pierce a diaphragm, so that the battery is short-circuited and is thermally out of control or even exploded; dead lithium is generated by volume expansion brought in the lithium deposition/dissolution process, so that the lithium is gradually pulverized to increase the internal resistance of the battery and further shorten the cycle life of the battery, and the like. Researchers start from metallic lithium negative electrodes, adopt alloyed negative electrodes (such as Li-Si, Li-Al, Li-In and the like) to improve the cycle performance to a certain extent, but adopt an alloy mode to reduce the energy density, and simultaneously the capacity of resisting volume expansion is also obviously reduced, and some researchers adopt an additive mode, adopt the additive mode to strengthen the SEI film on the surface, but the strength and the flexibility are not enough, and the additive cannot effectively prevent the battery short circuit caused by the penetration of a dendritic crystal diaphragm, and cannot prevent lithium corrosion caused by the attack of discharge intermediate products (superoxide and peroxy radicals) on the SEI film.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a polymer solid electrolyte, a nano composite diaphragm, a preparation method thereof and a lithium metal battery, so as to overcome the defects in the prior art.
The technical scheme for solving the technical problems is as follows: a polymer solid electrolyte comprises a film-forming agent, a lithium ion conductor, a reinforcing agent, a cross-linking agent and a solvent; the film forming agent is any two of PU, Nafion or PVDF; the lithium ion conductor is SiO2Or ZnO; the reinforcing agent is Al2O3Or LiCl; the cross-linking agent is glycerol; the solvent is NMP, DMF or CHCl3Any one of them.
The invention has the beneficial effects that: a lithium ion conductor is added into the polymer solid electrolyte, so that the effective transmission of lithium ions in the diaphragm can be ensured by utilizing the lithium ion conductor; the film-forming agent is added into the polymer solid electrolyte, the film formed by the film-forming agent forms a main carrier of the hydrophobic solid electrolyte layer, can load a lithium ion conductor, has certain elasticity and flexibility, and can resist dangerous accidents such as short circuit thermal runaway and even explosion caused by the fact that the generated lithium dendrite pierces the diaphragm.
On the basis of the technical scheme, the invention can be further improved as follows.
Further, the lithium ion conductor is SiO2The particle size is 15 +/-5 nm.
Further, the reinforcing agent is Al2O3。
Further, the film forming agents are PU and PVDF.
Further, the solvent is NMP.
A nanocomposite separator includes a porous substrate, and a polymer solid electrolyte filled or coated inside and on the surface of the porous substrate and dried.
The adoption of the further beneficial effects is as follows: the porous matrix used as the framework of the composite diaphragm can increase the liquid retention capacity of the diaphragm and promote the transmission of lithium ions, ensure that the electrode has good wettability, and reduce the internal resistance and the interface of the electrode; the polymer solid electrolyte is coated on the surface of a dry porous matrix to fill an internal pore structure, so that corrosion of a small amount of oxygen, carbon dioxide, water and the like to negative metal lithium through a diaphragm can be relieved, dangerous accidents such as short circuit thermal runaway and even explosion of the battery caused by penetration of generated lithium dendrites on the diaphragm can be inhibited, a good lithium protection effect can be achieved, and the cycling stability of lithium metal batteries such as lithium sulfur batteries and lithium air batteries using metal lithium as a negative electrode can be greatly improved.
Further, the thickness of the porous substrate is 20 to 50 μm, and the thickness of the polymer solid electrolyte covered on the surface of the porous substrate is 5 to 15 μm.
A preparation method of a nano composite diaphragm comprises the following steps:
s100, preparing polymer solid electrolyte slurry;
and S200, filling or coating polymer solid electrolyte slurry in the porous matrix and on the surface of the porous matrix, and drying to obtain the nano composite diaphragm.
The adoption of the further beneficial effects is as follows: the composite membrane can prevent the reaction of byproducts generated by the decomposition of a lithium cathode and an electrolyte and trace moisture contained in electrolyte, and can also utilize PU (polyurethane) to have certain flexibility and elasticity, thereby effectively relieving the safety problems of battery short circuit thermal runaway and even explosion caused by the penetration of the produced lithium dendrite on the membrane. The porous matrix can increase the liquid retention capacity of the diaphragm, so that the electrode interface has good wetting effect, the initial impedance of the interface is reduced, the internal resistance of the initial battery is reduced, the potential difference of charging and discharging is reduced, the charging voltage is reduced, the decomposition of electrolyte and the occurrence of side reaction are relieved, and meanwhile, the SiO in the composite diaphragm2The lithium ion battery can ensure the transmission of lithium ions between the anode and the cathode, thereby achieving better effect and greatly improving the cycling stability of lithium metal batteries such as lithium sulfur batteries, lithium air batteries and the like which take metal lithium as the cathode.
Further, the specific steps of S100 are as follows:
s110, mixing PU particles, NMP and SiO2Mixing the nanometer gel particles to obtain PU-SiO2A dispersion liquid;
s120, mixing PU-SiO2Dispersion liquidGlycerol, Al2O3Mixing the solid nano particles to obtain PU-SiO2-Glycerol-Al2O3A dispersion liquid;
s130, mixing PVDF, oxalic acid and NMP to obtain PVDF dispersion liquid;
s140, mixing the PVDF dispersion liquid with PU-SiO2-Glycerol-Al2O3Mixing the dispersion to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry.
A lithium metal battery comprising a nanocomposite separator.
The adoption of the further beneficial effects is as follows: when the nano composite diaphragm provided by the invention is used as a diaphragm in a lithium air battery and a lithium symmetric battery, lithium corrosion and growth of lithium dendrite can be effectively relieved, and the cycling stability of the battery can be improved to a great extent.
Drawings
FIG. 1 is a test chart of inventive example 1, a nanocomposite separator (right side, where Al is2 O 31% percent) and unfilled coated porous glass fibers (left) as a separator in the assembled lithium-air battery cycle curve;
FIG. 2 is a test chart of example 2 of the present invention, a nanocomposite separator (right side, wherein Al is2O3Percentage 3%) and unfilled coated porous glass fiber (left) as a separator for a lithium-air battery cycle curve;
FIG. 3 is a test chart of example 3 of the present invention, a nanocomposite separator (right side, wherein Al is present)2O35% percent) and unfilled coated porous glass fibers (left) as a separator for a lithium-air battery cycle curve;
FIG. 4 is a test chart of a lithium-air battery assembled with a nanocomposite separator (right side, where PVDF: oxalic acid is 1:0.5) and unfilled coated porous glass fiber (left side) as separators according to example 4 of the present invention;
FIG. 5 is a test chart of a lithium-air battery assembled with a nanocomposite separator (right side, where PVDF: oxalic acid is 1:2) and unfilled coated porous glass fiber (left side) as separators according to example 5 of the present invention;
FIG. 6 is an SEM image of comparative example 1, a being the lithium negative electrode morphology after cycling of battery 20 using the nanocomposite separator of example 2, b being the lithium negative electrode morphology after cycling of battery 20 using an unfilled coated glass fiber separator;
FIG. 7 is a battery charge-discharge curve corresponding to a lithium negative electrode with unfilled and coated glass fibers as a separator;
fig. 8 is a battery charge/discharge curve corresponding to a lithium negative electrode in which a separator is a nonwoven fabric coated with a solid electrolyte on the surface and inside thereof.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
A polymer solid electrolyte comprises a film-forming agent, a lithium ion conductor, a reinforcing agent, a cross-linking agent and a solvent; the film forming agent is any two of PU (polyurethane), Nafion (copolymer of polytetrafluoroethylene and perfluoro-3, 6-diepoxy-4-methyl-7-decene-sulfuric acid) or PVDF (polyvinylidene fluoride); the lithium ion conductor is SiO2Or ZnO; the reinforcing agent is Al2O3Or LiCl; the cross-linking agent is glycerol; the solvent is NMP (N-methylpyrrolidone), DMF (N, N-dimethylformamide) or CHCl3(chloroform); a lithium ion conductor is added into the polymer solid electrolyte, so that the effective transmission of lithium ions in the diaphragm can be ensured by utilizing the lithium ion conductor; the film-forming agent is added into the polymer solid electrolyte, the film formed by the film-forming agent forms a main carrier of the hydrophobic solid electrolyte layer, can load a lithium ion conductor, has certain elasticity and flexibility, and can resist dangerous accidents such as short circuit thermal runaway and even explosion caused by the fact that the generated lithium dendrite pierces the diaphragm.
The lithium ion conductor is preferably SiO2The grain diameter is 15 +/-5 nm and SiO2The composite membrane has good lithium affinity, can be used for ensuring the effective transmission of lithium ions in the composite membrane, and compared with ZnO, SiO2Not only has good affinity with lithium, but also can promote the transmission of lithium ions, and the lithium ion carrierHas the advantages of simple preparation, low cost of raw materials, rich sources and the like.
The reinforcing agent is preferably inorganic nano-particle Al2O3，Al2O3Compared with LiCl, the modified silicon carbide has higher hardness, is an amphoteric oxide, has certain catalytic activity, can promote the polymerization reaction, and has the advantages of simple preparation, low raw material cost, rich sources and the like.
The film forming agent is PU and PVDF, PU is high elasticity PU, PVDF is hydrophobic PVDF, compared with other, PU and PVDF have the advantages of higher intensity, larger elongation and better rebound resilience, and the raw materials are economical and practical, and the coating on the surface of the porous matrix can play a role in well relieving the dangerous accidents of short circuit thermal runaway even explosion and the like caused by the penetration of the produced lithium dendrite on the diaphragm, in addition, the hydrophobic layer formed by PU and PVDF can prevent the reaction of the lithium cathode and the byproducts produced by the decomposition of the electrolyte and the trace moisture contained in the electrolyte.
The cross-linking agent is selected from glycerol because the alcoholic hydroxyl groups in glycerol can cross-link with the polyurethane to form a stable network structure.
The solvent is preferably NMP, NMP with DMF or CHCl3Compared with the prior art, the PU-SiO-based solvent has the characteristics of low toxicity, high boiling point, strong dissolving power and the like as a polar solvent with strong selectivity and good stability, the solubility of PU in NMP is good, and in addition, NMP has good solubility on SiO2、Al2O3And PVDF has good dispersibility or solubility.
A nanocomposite separator includes a polymer solid electrolyte, the polymer solid electrolyte layer being a hydrophobic solid electrolyte layer.
The nanocomposite separator further includes a porous matrix, and a polymer solid electrolyte is filled or coated inside and on the surface of the porous matrix and dried.
The porous matrix used as the framework of the composite diaphragm can increase the liquid retention capacity of the diaphragm and promote the transmission of lithium ions, ensure that the electrode has good wettability, and reduce the internal resistance and the interface of the electrode; the polymer solid electrolyte is coated on the surface of a dry porous matrix to fill an internal pore structure, so that corrosion of a small amount of oxygen, carbon dioxide, water and the like to negative metal lithium through a diaphragm can be relieved, dangerous accidents such as short circuit thermal runaway and even explosion of the battery caused by penetration of generated lithium dendrites on the diaphragm can be inhibited, a good lithium protection effect can be achieved, and the cycling stability of lithium metal batteries such as lithium sulfur batteries and lithium air batteries using metal lithium as a negative electrode can be greatly improved.
Generally, the thickness of the porous substrate is 20 μm to 50 μm, and the thickness of the polymer solid electrolyte coated on the surface of the porous substrate is 5 μm to 15 μm.
The polymer solid electrolyte layer with the internal pore structure filled on the surface of the dried porous matrix can also prevent the lithium negative electrode from reacting with trace moisture contained in the electrolyte, thereby effectively relieving lithium corrosion.
The porous matrix is non-woven fabric or borosilicate glass fiber, the materials have porous structures, the porous structures are favorable for increasing the liquid retention capacity of the diaphragm and promoting the transmission of lithium ions, the electrode is ensured to have good wettability, and the internal resistance and the interface of the electrode are reduced, so that a better lithium protection effect can be achieved, and the cycling stability of lithium metal batteries such as lithium sulfur batteries and lithium air batteries using metal lithium as a negative electrode is greatly improved.
The polymer solid electrolyte is partially filled in the porous matrix, and a thin solid electrolyte membrane is formed on the surface of the polymer solid electrolyte, so that the lithium ion transmission can be effectively ensured, and meanwhile, the solid electrolyte layer formed on the surface has certain flexibility and higher elastic modulus, and the safety problems of battery short circuit thermal runaway and the like caused by the fact that the growing lithium dendrite pierces the diaphragm can be effectively relieved.
A preparation method of a nano composite diaphragm comprises the following steps:
s100, mixing PU particles, NMP and SiO2Nanogel particles, glycerin, Al2O3Mixing the solid nano particles, PVDF and oxalic acid to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
s200, filling or coating PU-SiO in the porous matrix and on the surface2-sweetoil-Al2O3And (3) drying the PVDF solid electrolyte slurry to obtain the nano composite diaphragm.
The specific steps of S100 are as follows:
s110, mixing PU particles, NMP and SiO2Mixing the nanometer gel particles to obtain PU-SiO2A dispersion liquid;
s120, mixing PU-SiO2Dispersion, glycerin, Al2O3Mixing the solid nano particles to obtain PU-SiO2-Glycerol-Al2O3A dispersion liquid;
s130, mixing PVDF, oxalic acid and NMP to obtain PVDF dispersion liquid;
s140, mixing the PVDF dispersion liquid with PU-SiO2-Glycerol-Al2O3Mixing the dispersion to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry.
The specific steps of S110 are as follows:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: (2-5), PU-SiO2The solid content in the dispersion liquid is 10-20%.
The specific steps of S120 are as follows:
adding glycerin to PU-SiO2Stirring the dispersion liquid for 15min to 30min to form PU-SiO2Glycerol mixtures of PU-SiO2The mass percent of the glycerol in the glycerol mixed solution is 1 to 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2Continuously stirring the glycerin mixed solution for 1 to 2 hours to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (B) is 1-8%.
The specific steps of S130 are as follows:
dispersing PVDF and oxalic acid into NMP, and stirring for 1-2 h, wherein the weight ratio of PVDF: the mass ratio of oxalic acid is 1 (0.5-3), and then ultrasonic treatment is carried out for 20-30 min to obtain PVDF dispersion liquid, wherein the solid content in the PVDF dispersion liquid is 5-15%.
The specific steps of S140 are as follows:
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3In the dispersion liquid, continuously stirring for 3 to 4 hours to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry.
The specific steps of S200 are as follows:
cutting the porous matrix, putting the cut porous matrix into a container for film paving, putting the porous matrix into a vacuum drying oven for drying and dewatering, and taking the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3And pouring the PVDF solid electrolyte slurry into a container paved with a porous matrix for natural drying, transferring the PVDF solid electrolyte slurry into a vacuum drying oven for drying at 60-80 ℃ when no obvious liquid is seen on the surface, and continuously drying for 8 hours after no water vapor is seen on the glass of the drying oven to obtain the nano composite diaphragm.
The container may be a pre-customized teflon recess for film laying.
The composite membrane can prevent the reaction of byproducts generated by the decomposition of a lithium cathode and an electrolyte and trace moisture contained in electrolyte, and can effectively relieve the safety problems of battery short circuit thermal runaway and even explosion and the like caused by the penetration of lithium dendrite through the membrane by utilizing certain flexibility and elasticity of PU (polyurethane)2Can ensure the transmission of lithium ions between the anode and the cathode, thereby achieving better effect and leading the lithium sulfur taking the metal lithium as the cathodeThe cycling stability of lithium metal batteries such as batteries and lithium air batteries is greatly improved.
The invention provides a lithium metal battery, which comprises a nano composite diaphragm, wherein the nano composite diaphragm provided by the invention can be used as a diaphragm in a lithium air battery and a lithium symmetric battery, can effectively relieve lithium corrosion and growth of lithium dendrite, and can also improve the cycling stability of the battery to a great extent.
Example 1
A preparation method of a nano composite diaphragm comprises the following steps:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: 5, PU-SiO2The solid content in the dispersion was 11%;
adding glycerin to PU-SiO2Stirring the dispersion for 20min to form PU-SiO2Glycerol mixtures of PU-SiO2The mass percent of the glycerol in the glycerol mixed solution is 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2Continuously stirring the glycerin mixed solution for 2 hours to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (A) is 1%;
PVDF and oxalic acid were dispersed in NMP and stirred for 1h, PVDF: the mass ratio of oxalic acid is 1:1, then ultrasonic treatment is carried out for 30min to obtain PVDF dispersion liquid, and the solid content in the PVDF dispersion liquid is 8%;
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3Adding into the dispersion, and continuing stirring for 3h to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
cutting the porous non-woven fabric, putting the cut porous non-woven fabric into a pre-customized polytetrafluoroethylene groove for film paving, and puttingDrying in a vacuum drying oven to remove water, and taking out the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3And adding the PVDF solid electrolyte slurry into a polytetrafluoroethylene groove paved with porous non-woven fabrics, naturally drying, transferring the PVDF solid electrolyte slurry into a vacuum drying oven for drying at 60 ℃ when no obvious liquid is seen on the surface, and continuously drying for 8 hours after no water vapor is seen on the glass of the drying oven to obtain the nano composite diaphragm.
Assembled lithium-air batteries were tested for battery performance using the nanocomposite separator and unfilled coated porous glass fiber as the separator under equivalent conditions, lithium pieces (d 450 μm) as the negative electrode, 0.3mg/cm2Lithium-air battery with MWCNTs @ foamed nickel as positive electrode is 1A g-1Constant capacity at current density (1000 mAhg)-1) The cycle curve of charge and discharge cycles and the test result are shown in figure 1, and after the measure is used, the number of battery cycle times is increased from 32 times to 50 times, which is greatly improved. The specific test conditions were: the cycle life of the battery was evaluated by conducting a constant current charge/discharge cycle for a long time in a test container (99.9%, degree of vacuum of 0.1atm) in a pure oxygen atmosphere using a CT2001A-5V type battery test system manufactured by blue electronic corporation, Wuhan City, in which cutoff potentials of 2.0V and 4.5V were set and a current density of 1A g was set-1Setting the specific charge/discharge capacity to 1000mAh g based on the load mass of the positive electrode active material-1。
Example 2
A preparation method of a nano composite diaphragm comprises the following steps:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: 5, PU-SiO2The solid content in the dispersion was 11%;
adding glycerin to PU-SiO2Stirring the dispersion for 20min to form PU-SiO2Glycerol mixtures of PU-SiO2-glycerol mixturesThe mass percent of the glycerol is 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2Continuously stirring the glycerin mixed solution for 2 hours to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (A) is 3%;
PVDF and oxalic acid were dispersed in NMP and stirred for 1h, PVDF: the mass ratio of oxalic acid is 1:1, then ultrasonic treatment is carried out for 30min to obtain PVDF dispersion liquid, and the solid content in the PVDF dispersion liquid is 8%;
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3Adding into the dispersion, and continuing stirring for 3h to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
cutting the porous non-woven fabric, putting the cut porous non-woven fabric into a pre-customized polytetrafluoroethylene groove for film paving, putting the porous non-woven fabric into a vacuum drying oven for drying and dewatering, and taking the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3And adding the PVDF solid electrolyte slurry into a polytetrafluoroethylene groove paved with porous non-woven fabrics, naturally drying, transferring the PVDF solid electrolyte slurry into a vacuum drying oven for drying at 60 ℃ when no obvious liquid is seen on the surface, and continuously drying for 8 hours after no water vapor is seen on the glass of the drying oven to obtain the nano composite diaphragm.
Assembled lithium-air batteries were tested for battery performance using the nanocomposite separator and unfilled coated porous glass fiber as the separator under equivalent conditions, lithium pieces (d 450 μm) as the negative electrode, 0.3mg/cm2Lithium-air battery with MWCNTs @ foamed nickel as positive electrode is 1A g-1Constant capacity at current density (1000mAh g)-1) The test result of the cycle curve of the charge and discharge cycle is shown in fig. 2, after the measure is used, the cycle number of the battery is increased from 32 times to 102 times, and the cycle number is greatly improved, and the specific test conditions are as follows: a battery test system of CT2001A-5V type manufactured by blue electronic corporation, Wuhan City, was used to perform constant current charging for a long time in a test container (99.9%, degree of vacuum of 0.1atm) in a pure oxygen atmosphereDischarge cycle, evaluation of the cycle life of the battery, wherein cut-off potentials of 2.0V and 4.5V and a current density of 1A g were set-1Setting the specific charge/discharge capacity to 1000mAh g based on the load mass of the positive electrode active material-1。
Example 3
A preparation method of a nano composite diaphragm comprises the following steps:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: 5, PU-SiO2The solid content in the dispersion was 11%;
adding glycerin to PU-SiO2Stirring the dispersion for 20min to form PU-SiO2Glycerol mixtures of PU-SiO2The mass percent of the glycerol in the glycerol mixed solution is 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2Continuously stirring the glycerin mixed solution for 2 hours to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (A) is 5%;
PVDF and oxalic acid were dispersed in NMP and stirred for 1h, PVDF: the mass ratio of oxalic acid is 1:1, then ultrasonic treatment is carried out for 30min to obtain PVDF dispersion liquid, and the solid content in the PVDF dispersion liquid is 8%;
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3Adding into the dispersion, and continuing stirring for 3h to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
cutting the porous non-woven fabric, putting the cut porous non-woven fabric into a pre-customized polytetrafluoroethylene groove for film paving, putting the porous non-woven fabric into a vacuum drying oven for drying and dewatering, and taking the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3PVDF solid electrolyte slurry additionPutting the membrane into a polytetrafluoroethylene groove paved with porous non-woven fabrics for natural drying, transferring the membrane into a vacuum drying oven for drying at 60 ℃ when no obvious liquid is seen on the surface, and continuously drying for 8 hours after no water vapor is seen on the glass of the drying oven to obtain the nano composite membrane.
Assembled lithium-air batteries were tested for battery performance using the nanocomposite separator and unfilled coated porous glass fiber as the separator under equivalent conditions, lithium pieces (d 450 μm) as the negative electrode, 0.3mg/cm2Lithium-air battery with MWCNTs @ foamed nickel as positive electrode is 1A g-1Constant capacity at current density (1000 mAhg)-1) The test result of the cycle curve of the charge and discharge cycle is shown in fig. 3, after the measure is used, the cycle number of the battery is increased from 32 times to 93 times, and the cycle number is greatly improved, and the specific test conditions are as follows: the cycle life of the battery was evaluated by conducting a constant current charge/discharge cycle for a long time in a test container (99.9%, degree of vacuum of 0.1atm) in a pure oxygen atmosphere using a CT2001A-5V type battery test system manufactured by blue electronic corporation, Wuhan City, in which cutoff potentials of 2.0V and 4.5V were set and a current density of 1A g was set-1Setting the specific charge/discharge capacity to 1000mAh g based on the load mass of the positive electrode active material-1。
Example 4
A preparation method of a nano composite diaphragm comprises the following steps:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: 5, PU-SiO2The solid content in the dispersion was 11%;
adding glycerin to PU-SiO2Stirring the dispersion for 20min to form PU-SiO2Glycerol mixtures of PU-SiO2The mass percent of the glycerol in the glycerol mixed solution is 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2-continuation of glycerol mixtureStirring for 2h to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (A) is 3%,
PVDF and oxalic acid were dispersed in NMP and stirred for 1h, PVDF: the mass ratio of oxalic acid is 1:0.5, and then ultrasonic treatment is carried out for 30min to obtain PVDF dispersion liquid, wherein the solid content in the PVDF dispersion liquid is 6%;
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3Adding into the dispersion, and continuing stirring for 3h to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
cutting the porous non-woven fabric, putting the cut porous non-woven fabric into a pre-customized polytetrafluoroethylene groove for film paving, putting the porous non-woven fabric into a vacuum drying oven for drying and dewatering, and taking the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3And adding the PVDF solid electrolyte slurry into a polytetrafluoroethylene groove paved with porous non-woven fabrics, naturally drying, transferring the PVDF solid electrolyte slurry into a vacuum drying oven for drying at 60 ℃ when no obvious liquid is seen on the surface, and continuously drying for 8 hours after no water vapor is seen on the glass of the drying oven to obtain the nano composite diaphragm.
Assembled lithium-air batteries were tested for battery performance using the nanocomposite separator and unfilled coated porous glass fiber as the separator under equivalent conditions, lithium pieces (d 450 μm) as the negative electrode, 0.3mg/cm2Lithium-air battery with MWCNTs @ foamed nickel as positive electrode is 1A g-1Constant capacity at current density (1000mAh g)-1) The test result of the cycle curve of the charge and discharge cycle is shown in fig. 4, after the measure is used, the cycle number of the battery is improved from 32 times to 89 times, and the test conditions are as follows: the cycle life of the battery was evaluated by conducting a constant current charge/discharge cycle for a long time in a test container (99.9%, degree of vacuum of 0.1atm) in a pure oxygen atmosphere using a CT2001A-5V type battery test system manufactured by blue electronic corporation, Wuhan City, in which cutoff potentials of 2.0V and 4.5V were set and a current density of 1A g was set-1Based on positive active materialsLoad quality, setting the specific charge/discharge capacity to 1000mAh g-1。
Example 5
A preparation method of a nano composite diaphragm comprises the following steps:
slowly adding PU particles into NMP under stirring, continuously stirring for 4h until the PU particles are completely dissolved, and then adding SiO2Slowly adding the nano gel particles into the solution in a stirring state, and continuously stirring for 4 hours to obtain PU-SiO2Dispersion of PU particles and SiO2The weight ratio of the nanogel particles is 1: 5, PU-SiO2The solid content in the dispersion was 11%;
adding glycerin to PU-SiO2Stirring the dispersion for 20min to form PU-SiO2Glycerol mixtures of PU-SiO2The mass percent of the glycerol in the glycerol mixed solution is 5 percent, and then Al is added2O3Adding solid nano particles into PU-SiO with continuous stirring2Continuously stirring the glycerin mixed solution for 2 hours to form PU-SiO2-Glycerol-Al2O3Dispersion of, among others, PU-SiO2-Glycerol-Al2O3Al in the dispersion2O3The mass percentage of (A) is 3%;
PVDF and oxalic acid were dispersed in NMP and stirred for 1h, PVDF: the mass ratio of oxalic acid is 1:2, then ultrasonic treatment is carried out for 30min to obtain PVDF dispersion liquid, and the solid content in the PVDF dispersion liquid is 12%;
the PVDF dispersion was slowly added to the continuously stirred PU-SiO2-Glycerol-Al2O3Adding into the dispersion, and continuing stirring for 3h to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry;
cutting the porous non-woven fabric, putting the cut porous non-woven fabric into a pre-customized polytetrafluoroethylene groove for film paving, putting the porous non-woven fabric into a vacuum drying oven for drying and dewatering, and taking the prepared PU-SiO in an argon atmosphere2-Glycerol-Al2O3PVDF solid electrolyte slurry is added into a polytetrafluoroethylene groove paved with porous non-woven fabric for natural drying, and when no obvious liquid is seen on the surface, the PVDF solid electrolyte slurry is transferred into a vacuum drying oven at 60 DEG CAnd (4) drying until no water vapor is seen on the glass of the drying oven, and then continuously drying for 8 hours to obtain the nano composite diaphragm.
The assembled lithium-air battery is used for testing the performance of the battery, and the nano composite diaphragm and the unfilled and coated porous glass fiber are used as diaphragms under the same conditions, a lithium sheet (d is 14mm) is used as a negative electrode, and the thickness of the lithium sheet is 0.3mg/cm2Lithium-air battery with MWCNTs @ foamed nickel as positive electrode is 1A g-1Constant capacity at current density (1000mAh g)-1) The test result of the cycle curve of the charge and discharge cycle is shown in fig. 5, after the measure is used, the cycle number of the battery is increased from 32 times to 73 times, and the cycle number is greatly improved, and the specific test conditions are as follows: the cycle life of the battery was evaluated by conducting a constant current charge/discharge cycle for a long time in a test container (99.9%, degree of vacuum of 0.1atm) in a pure oxygen atmosphere using a CT2001A-5V type battery test system manufactured by blue electronic corporation, Wuhan City, in which cutoff potentials of 2.0V and 4.5V were set and a current density of 1A g was set-1Setting the specific charge/discharge capacity to 1000mAh g based on the load mass of the positive electrode active material-1。
Examples 1, 2 and 3 differ in Al2O3Different in the amount of addition of (A), examples 2, 4 and 5 are different in the ratio of PVDF and oxalic acid added and in the ratio of Al2O3The addition amount of (b) and the ratio of PVDF to oxalic acid play an important role in the process of preparing the nano composite membrane.
Comparative example 1
Scanning electron microscope tests are carried out on the negative electrode after the unfilled and coated glass fibers are used as the diaphragm and the non-woven fabrics with the surfaces and the interiors filled and coated with the solid electrolyte are respectively used as the diaphragm (the nano composite diaphragm of example 2) in the lithium-oxygen battery for circulating for 20 cycles, the test conditions are the same as the above examples, the obtained SEM images are shown in figure 6, a) is a lithium negative electrode corresponding to the unfilled and coated glass fibers as the diaphragm, b) is a lithium negative electrode with the surfaces and the interiors filled and coated with the solid electrolyte, the untreated lithium negative electrode has a lot of powder on the surface and has larger thickness reduction ratio on the cross section thickness, which shows that the metal lithium negative electrode is seriously corroded by water, carbon dioxide, oxygen and some side reactions and pulverized, and the lithium negative electrode with the surfaces and the interiors filled and coated with the solid electrolyte as the diaphragm hardly has smooth powder and large variation of the surface thickness, the lithium ion battery has the advantages that almost no corrosion is caused under the condition, the lithium protection effect is good, as shown in fig. 7, the battery charge-discharge curve corresponding to the lithium cathode corresponding to the non-filled and coated glass fiber as the diaphragm, as shown in fig. 8, the battery charge-discharge curve corresponding to the lithium cathode of which the surface and the inside are filled with the non-woven fabric coated with the solid electrolyte as the diaphragm, the overpotential of the battery charge-discharge after the composite diaphragm is used is obviously relieved, the corrosion of the surface cathode side is obviously relieved, the interface internal resistance is reduced, the internal resistance of the battery is reduced, the charge-discharge overpotential is further reduced, the side reaction of the anode is reduced, and the composite diaphragm is used for relieving the corrosion of the cathode and playing a certain role in relieving the side reaction of the anode.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (10)
1. A polymer solid electrolyte is characterized by comprising a film-forming agent, a lithium ion conductor, a reinforcing agent, a cross-linking agent and a solvent; the film forming agent is any two of PU, Nafion or PVDF; the lithium ion conductor is SiO2Or ZnO; the reinforcing agent is Al2O3Or LiCl; the cross-linking agent is glycerol; the solvent is NMP, DMF or CHCl3Any one of them.
2. The polymer solid electrolyte according to claim 1, wherein the lithium ion conductor is SiO2The particle size is 15 +/-5 nm.
3. A polymer solid electrolyte according to claim 1,the reinforcing agent is Al2O3。
4. The polymer solid electrolyte according to claim 1, wherein said film forming agents are PU and PVDF.
5. The polymer solid electrolyte according to claim 1, wherein the solvent is NMP.
6. A nanocomposite separator comprising a porous substrate and a polymer solid electrolyte according to any one of claims 1 to 5 filled or coated in and on the surface of the porous substrate and dried.
7. The nanocomposite separator according to claim 6, wherein the thickness of the porous matrix is 20 μm to 50 μm, and the thickness of the polymer solid electrolyte covered on the surface of the porous matrix is 5 μm to 15 μm.
8. A preparation method of a nano composite diaphragm is characterized by comprising the following steps:
s100, preparing the polymer solid electrolyte slurry as defined in any one of claims 1 to 5;
and S200, filling or coating polymer solid electrolyte slurry in the porous matrix and on the surface of the porous matrix, and drying to obtain the nano composite diaphragm.
9. The method for preparing a nanocomposite separator according to claim 8, wherein the specific steps of S100 are as follows:
s110, mixing PU particles, NMP and SiO2Mixing the nanometer gel particles to obtain PU-SiO2A dispersion liquid;
s120, mixing PU-SiO2Dispersion, glycerin, Al2O3Mixing the solid nano particles to obtain PU-SiO2-Glycerol-Al2O3A dispersion liquid;
s130, mixing PVDF, oxalic acid and NMP to obtain PVDF dispersion liquid;
s140, mixing the PVDF dispersion liquid with PU-SiO2-Glycerol-Al2O3Mixing the dispersion to obtain PU-SiO2-Glycerol-Al2O3-PVDF solid electrolyte slurry.
10. A lithium metal battery comprising the nanocomposite separator obtained by the preparation method according to claim 8 or 9.
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Cited By (2)
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| CN111933998A (en) * | 2020-09-10 | 2020-11-13 | 苏州清陶新能源科技有限公司 | Composite electrolyte, preparation method thereof, composite electrode plate containing composite electrolyte and battery |
| CN114335898A (en) * | 2021-12-31 | 2022-04-12 | 北京卫蓝新能源科技有限公司 | Diaphragm for metal lithium battery, preparation method of diaphragm and corresponding metal lithium battery |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1452794A (en) * | 2000-05-24 | 2003-10-29 | 株式会社华仁电池 | Microporous solid electrolytes and methods for preparing them |
| CN101552359A (en) * | 2009-05-12 | 2009-10-07 | 湖南大学 | Micro-nano porous structure polymer electrolyte membrane used for lithium ion battery and method of producing the same |
| CN104852086A (en) * | 2015-05-29 | 2015-08-19 | 上海交通大学 | Polymer electrolyte for lithium air cell and preparation method of polymer electrolyte |
| CN106410269A (en) * | 2016-04-12 | 2017-02-15 | 中国科学院大学 | All-solid-state composite polymer electrolyte and preparation method thereof |
| US20170263977A1 (en) * | 2016-03-09 | 2017-09-14 | Samsung Sdi Co., Ltd. | Secondary battery |
| CN107170941A (en) * | 2017-05-28 | 2017-09-15 | 桂林理工大学 | A kind of preparation method of the nano combined barrier film of lithium-air battery |
| CN107293779A (en) * | 2017-05-10 | 2017-10-24 | 华南农业大学 | A kind of preparation method based on silicon based anode material polymer dielectric film |
| CN108878964A (en) * | 2018-06-04 | 2018-11-23 | 南京工业大学 | Composite gel polymer electrolyte, preparation method and application thereof in lithium air battery |
| CN109075384A (en) * | 2016-06-14 | 2018-12-21 | 三星Sdi株式会社 | For the composite electrolyte of lithium metal battery, preparation method and including the lithium metal battery of the composite electrolyte |
| CN109565075A (en) * | 2016-07-28 | 2019-04-02 | 三星Sdi株式会社 | Electrolyte for lithium metal battery and the lithium metal battery comprising the electrolyte |
| CN109755630A (en) * | 2017-11-03 | 2019-05-14 | 深圳格林德能源集团有限公司 | A kind of Recombination gel polymer dielectric preparation method and its lithium ion battery |
| CN110112458A (en) * | 2019-05-16 | 2019-08-09 | 广东工业大学 | A kind of halloysite nanotubes modified polyurethane solid electrolyte, preparation method and its battery |
| CN110165295A (en) * | 2019-06-03 | 2019-08-23 | 宁德新能源科技有限公司 | Composite electrolyte and the electrochemical appliance and electronic device for using it |
-
2019
- 2019-12-14 CN CN201911287044.6A patent/CN111342120B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1452794A (en) * | 2000-05-24 | 2003-10-29 | 株式会社华仁电池 | Microporous solid electrolytes and methods for preparing them |
| CN101552359A (en) * | 2009-05-12 | 2009-10-07 | 湖南大学 | Micro-nano porous structure polymer electrolyte membrane used for lithium ion battery and method of producing the same |
| CN104852086A (en) * | 2015-05-29 | 2015-08-19 | 上海交通大学 | Polymer electrolyte for lithium air cell and preparation method of polymer electrolyte |
| US20170263977A1 (en) * | 2016-03-09 | 2017-09-14 | Samsung Sdi Co., Ltd. | Secondary battery |
| CN106410269A (en) * | 2016-04-12 | 2017-02-15 | 中国科学院大学 | All-solid-state composite polymer electrolyte and preparation method thereof |
| CN109075384A (en) * | 2016-06-14 | 2018-12-21 | 三星Sdi株式会社 | For the composite electrolyte of lithium metal battery, preparation method and including the lithium metal battery of the composite electrolyte |
| CN109565075A (en) * | 2016-07-28 | 2019-04-02 | 三星Sdi株式会社 | Electrolyte for lithium metal battery and the lithium metal battery comprising the electrolyte |
| CN107293779A (en) * | 2017-05-10 | 2017-10-24 | 华南农业大学 | A kind of preparation method based on silicon based anode material polymer dielectric film |
| CN107170941A (en) * | 2017-05-28 | 2017-09-15 | 桂林理工大学 | A kind of preparation method of the nano combined barrier film of lithium-air battery |
| CN109755630A (en) * | 2017-11-03 | 2019-05-14 | 深圳格林德能源集团有限公司 | A kind of Recombination gel polymer dielectric preparation method and its lithium ion battery |
| CN108878964A (en) * | 2018-06-04 | 2018-11-23 | 南京工业大学 | Composite gel polymer electrolyte, preparation method and application thereof in lithium air battery |
| CN110112458A (en) * | 2019-05-16 | 2019-08-09 | 广东工业大学 | A kind of halloysite nanotubes modified polyurethane solid electrolyte, preparation method and its battery |
| CN110165295A (en) * | 2019-06-03 | 2019-08-23 | 宁德新能源科技有限公司 | Composite electrolyte and the electrochemical appliance and electronic device for using it |
Non-Patent Citations (1)
| Title |
|---|
| KUN LUO ET AL: "Enhanced Cycling Stability of Li-O2 Batteries by Using a Polyurethane/SiO2/Glass Fiber Nanocomposite Separator", 《JOURNAL OF MATERIALS CHEMISTRY A》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111933998A (en) * | 2020-09-10 | 2020-11-13 | 苏州清陶新能源科技有限公司 | Composite electrolyte, preparation method thereof, composite electrode plate containing composite electrolyte and battery |
| CN111933998B (en) * | 2020-09-10 | 2021-02-02 | 苏州清陶新能源科技有限公司 | Composite electrolyte, preparation method thereof, composite electrode plate containing composite electrolyte and battery |
| CN114335898A (en) * | 2021-12-31 | 2022-04-12 | 北京卫蓝新能源科技有限公司 | Diaphragm for metal lithium battery, preparation method of diaphragm and corresponding metal lithium battery |
| CN114335898B (en) * | 2021-12-31 | 2024-02-23 | 北京卫蓝新能源科技有限公司 | Diaphragm for metal lithium battery, preparation method of diaphragm and corresponding metal lithium battery |
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| CN111342120B (en) | 2021-08-31 |
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Denomination of invention: Polymer solid electrolyte, nanocomposite separator and their preparation method and lithium metal battery Granted publication date: 20210831 Pledgee: Guanggu Branch of Wuhan Rural Commercial Bank Co.,Ltd. Pledgor: WUHAN RUIKEMEI NEW ENERGY Co.,Ltd. Registration number: Y2024980018586 |