CN110854345B - High-performance lithium-sulfur battery diaphragm and preparation method and application thereof - Google Patents
High-performance lithium-sulfur battery diaphragm and preparation method and application thereof Download PDFInfo
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- 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
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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
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- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
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- H—ELECTRICITY
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- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/431—Inorganic material
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- H—ELECTRICITY
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- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
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- H—ELECTRICITY
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
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- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses a high-performance lithium-sulfur battery diaphragm and a preparation method and application thereof, and belongs to the technical field of battery diaphragms. The invention relates to a high-performance lithium-sulfur battery diaphragm, which comprises a porous diaphragm matrix, wherein the preparation raw materials of the porous diaphragm matrix comprise the following components in percentage by mass: 20-40% of polyethylene, 0.5-10% of carbon nano tube and 0.5-10% of conductive carbon black and/or graphene; the preparation process of the diaphragm comprises the following steps: blending and modifying polyethylene, carbon nano tubes and conductive carbon black and/or graphene through an extruder, and then preparing a cellular porous diaphragm matrix through biaxial tension and extraction; and coating or compounding an inorganic nano ceramic layer on the surface of the porous diaphragm substrate to obtain the high-performance lithium-sulfur battery diaphragm. By adopting the technical scheme of the invention, the shuttle effect of lithium polysulfide of the lithium-sulfur battery can be effectively inhibited, so that the service performance of the lithium-sulfur battery is improved.
Description
Technical Field
The invention belongs to the technical field of battery diaphragms, and particularly relates to a high-performance lithium-sulfur battery diaphragm and a preparation method and application thereof.
Background
Energy crisis and environmental problems are two major challenges facing the present human society, so that adjusting energy structure and developing clean renewable new energy have become urgent needs of the present society. In all electrochemical energy storage systems, lithium secondary batteries are widely researched and applied by virtue of the advantages of high voltage, high specific capacity, long cycle life, no environmental pollution and the like. The elemental sulfur has extremely high theoretical capacity and energy density, and meanwhile, the sulfur has a series of advantages of no toxicity, environmental friendliness, wide raw material source, low cost and the like. Therefore, the lithium-sulfur battery is predicted to be the next generation of energy storage system with great development prospect, and will play a key role in the development of emerging advanced technology industries, such as pure electric vehicles.
However, the discharging process of the lithium-sulfur battery is accompanied by the dissolution of polysulfide, and polysulfide shuttles back and forth between the positive electrode and the negative electrode during the charging process under the promotion of the concentration gradient and the electrochemical gradient, thereby causing the reduction of coulombic efficiency and the capacity attenuation. Therefore, if the shuttle effect can be effectively inhibited, the performance of the lithium-sulfur battery can be greatly improved. The separator, which is one of the important components of the lithium sulfur battery as a channel for ion transport of the lithium sulfur battery, has been developed to seriously affect the performance of the lithium sulfur battery. The good lithium-sulfur battery diaphragm can not only ensure the normal transmission of lithium ions, but also block the shuttling of polysulfide, and can provide certain conductivity, thereby exerting the capacity of the electrode to the maximum extent. However, the currently widely used commercial polyolefin separator is difficult to inhibit the shuttle effect, resulting in low charging and discharging efficiency.
The current research is mainly to inhibit the shuttling of lithium polysulfide by preparing a functional coating on the surface of a membrane-based film. For example, chinese patent application No. 201910193367.2 inhibits the occurrence of the shuttling effect by loading polyoxometallate-phosphotungstic acid and polyvinylidene fluoride onto a lithium sulfur battery separator PP membrane. The application with the Chinese patent application number of 2018109608097 discloses a functional diaphragm for a lithium-sulfur battery, a preparation method thereof and application thereof in the lithium-sulfur battery, wherein the functional diaphragm consists of a polymer diaphragm substrate and a functional modification layer coated on one side surface of the polymer diaphragm substrate, wherein the functional modification layer comprises a binder, a conductive carbon material and a dendritic branched macromolecule.
For another example, chinese patent application No. 2018101907885 discloses a method for preparing a surface-modified high-performance lithium-sulfur battery separator, which comprises the following steps: dissolving a multi-walled carbon nanotube in absolute ethyl alcohol to prepare a first suspension; mixing a multi-wall carbon nano tube, conductive carbon black and polyethyleneimine according to a proportion, and dissolving in absolute ethyl alcohol to prepare a second suspension; preparing a circular polyethylene diaphragm by using a tablet press, and attaching the circular polyethylene diaphragm to the glass slide; coating the first suspension on the polyethylene diaphragm by using an LBS method, then drying, and repeating the steps of coating the first suspension and drying; drying the polyethylene diaphragm; coating the second suspension on the polyethylene diaphragm repeatedly coated with the first suspension by using an LBS method, and then drying for at least five times; and after the required number of layers is reached, drying the polyethylene diaphragm to obtain the surface-modified high-performance lithium-sulfur battery diaphragm.
The applications mentioned above all inhibit shuttling of lithium polysulfide by preparing a functional coating on the surface of the separator substrate, but the inhibition effect is very limited, so how to further improve the inhibition effect of the shuttling phenomenon of lithium polysulfide in the lithium sulfur battery has important significance for ensuring the service performance of the lithium sulfur battery.
Disclosure of Invention
1. Problems to be solved
The invention aims to overcome the defect that the service performance of a lithium-sulfur battery is affected by shuttle effect of lithium polysulfide which is easy to occur in the using process of the conventional lithium-sulfur battery, and provides a high-performance lithium-sulfur battery diaphragm and a preparation method and application thereof. By adopting the technical scheme of the invention, the shuttle effect of lithium polysulfide of the lithium-sulfur battery can be effectively inhibited, so that the service performance of the lithium-sulfur battery is improved.
2. Technical scheme
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the high-performance lithium-sulfur battery diaphragm comprises a porous diaphragm matrix, wherein the preparation raw materials of the porous diaphragm matrix comprise the following components in percentage by mass: 20-40% of polyethylene, 0.5-10% of carbon nano tube and 0.5-10% of conductive carbon black and/or graphene.
Furthermore, the adding proportion of the carbon nano tube is preferably 2-5%, and the adding total amount of the conductive carbon black and the graphene is preferably 5-10%.
Furthermore, the porous diaphragm substrate is a honeycomb-shaped three-dimensional mesh porous membrane with certain conductivity, wherein the carbon nano tubes are distributed along the thickness direction of the diaphragm, the conductive carbon black and the graphene are distributed along the plane direction of the diaphragm, and the carbon nano tubes and the conductive carbon black and/or the graphene form a three-dimensional network conductor.
Furthermore, the surface of the porous diaphragm substrate is provided with an inorganic nano ceramic layer.
Furthermore, the thickness of the porous diaphragm substrate is 5-30 mu m, and the electric conductivity of the porous diaphragm substrate is not less than 10 -6 S/cm, the thickness of the inorganic nano ceramic layer is 1-10 mu m, and the porosity is 50-80%; the ceramic is one or a combination of more of silicon dioxide, aluminum oxide, boehmite, titanium dioxide, magnesium oxide, barium sulfate and molybdenum disulfide.
Furthermore, the coating of the inorganic nano ceramic layer comprises the following components in parts by weight: 0.2-5 parts of water-soluble polymer thickener, 0.2-5 parts of water-based dispersant, 17.6-45 parts of ceramic particles and 2-7 parts of water-based adhesive.
Furthermore, the aqueous polymer thickener is one or a combination of several of hydroxyethyl cellulose, methyl hydroxyethyl cellulose and sodium carboxymethyl cellulose; the water-based dispersant is one or a combination of more of polyethylene glycol, polyacrylic acid, sodium polyacrylate and potassium polyacrylate; the water-based adhesive is one or a combination of a plurality of styrene-acrylic latex, styrene-butadiene latex, polymethyl methacrylate and polyethyl acrylate.
Secondly, the preparation method of the high-performance lithium-sulfur battery diaphragm is characterized in that polyethylene, carbon nano tubes and conductive carbon black and/or graphene are subjected to blending modification through an extruder, and then a cellular porous diaphragm matrix is prepared through biaxial stretching and extraction; and coating or compounding an inorganic nano ceramic layer on the surface of the porous diaphragm substrate to obtain the high-performance lithium-sulfur battery diaphragm.
Furthermore, the longitudinal stretching multiplying power is 5-8 times during bidirectional stretching, and the stretching temperature is 90-120 ℃; the transverse stretching rate is 6-9 times, and the stretching temperature is 110-125 ℃; the preparation process of the coating of the inorganic nano ceramic layer comprises the following steps: uniformly stirring and mixing a water-soluble polymer thickener, a water-based dispersant and water to obtain a mixture 1; then adding the ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; and adding the aqueous adhesive into the mixture 2, and uniformly stirring to form the inorganic nano ceramic layer coating.
Thirdly, the diaphragm of the invention is applied to the lithium-sulfur battery.
3. Advantageous effects
Compared with the prior art, the invention has the beneficial effects that:
(1) the invention relates to a high-performance lithium-sulfur battery diaphragm which comprises a porous diaphragm substrate, wherein the preparation raw material of the porous diaphragm substrate comprises one or two of polyethylene, a carbon nano tube and conductive carbon black and graphene, and the carbon nano tube and the conductive carbon black and/or the graphene are added into the polyethylene raw material, so that the carbon nano tube and the conductive carbon black and/or the graphene are mutually embedded to form a three-dimensional conductive net structure, so that on one hand, the conductivity of the porous substrate can be effectively improved, the problem of poor conductivity of sulfur in a lithium-sulfur battery is solved, the polarization effect is reduced, the shuttle effect can be reduced, and the battery performance is improved; on the other hand, the formed three-dimensional conductive network structure has good adsorption effect on polysulfide, so that the shuttle effect can be further prevented.
(2) According to the high-performance lithium-sulfur battery diaphragm, the addition amounts of the carbon nano tube, the conductive carbon black and the graphene are optimally designed, so that the inhibition effect of the shuttle effect can be further ensured, and the mechanical strength and the safety performance of the obtained diaphragm are improved; in addition, the surface of the porous separator substrate of the invention is also coated with an inorganic nanoceramic layer, so that on one hand, the insulating property of the finally obtained separator can be ensured, and on the other hand, the shuttle of polysulfide can be better inhibited.
(3) According to the preparation method of the high-performance lithium-sulfur battery diaphragm, polyethylene, the carbon nano tube, the conductive carbon black and/or graphene are subjected to blending modification through an extruder, and then subjected to bidirectional stretching and extraction, so that a three-dimensional mesh porous diaphragm matrix with certain conductivity can be prepared, and finally, an inorganic nano ceramic layer is coated on the surface of the diaphragm matrix, so that the shuttle effect can be effectively inhibited, and the use performance of the lithium-sulfur battery can be improved.
(4) According to the preparation method of the high-performance lithium-sulfur battery diaphragm, the addition proportion of the polyethylene, the carbon nano tube, the conductive carbon black and/or the graphene and the specific preparation process parameters are optimally designed, so that the inhibition effect of the shuttle effect can be ensured, the mechanical strength and the heat resistance of the obtained diaphragm can be further improved, and the firmness of the combination of the inorganic nano ceramic layer and the porous diaphragm substrate can be ensured.
Drawings
Fig. 1 is a schematic structural view of a lithium sulfur separator according to the present invention;
fig. 2 is a microscopic structure view of a lithium sulfur separator according to the present invention.
Detailed Description
As shown in fig. 1 and 2, the high-performance lithium-sulfur battery separator provided by the invention comprises a porous separator substrate and an inorganic nano ceramic layer coated on the surface of the porous separator substrate, wherein the preparation raw material of the porous separator substrate comprises the following components in percentage by mass: 20-40% of polyethylene, 0.5-10% of carbon nano tube and 0.5-10% of conductive carbon black and/or graphene. The porous diaphragm substrate is a honeycomb porous membrane with certain conductivity, wherein carbon nano tubes are distributed along the thickness direction of the diaphragm, conductive carbon black and graphene are distributed along the plane direction of the diaphragm, and the carbon nano tubes and the conductive carbon black and/or the graphene are mutually embedded to form a three-dimensional network conductor.
Aiming at the problem that the lithium sulfur battery is easy to generate the shuttling effect of lithium polysulfide so as to influence the capacity exertion and the commercial application of the battery, the existing research is generally to directly coat a functional coating on the surface of a separator, but the effect is not obvious. According to the preparation method, the carbon nano tube and one or two of conductive carbon black and graphene are added into the raw material polyethylene of the diaphragm substrate, so that the diaphragm substrate is modified, the diaphragm substrate is creatively prepared into the three-dimensional mesh porous membrane with certain conductivity, and then the whole insulating property of the diaphragm is ensured by coating the inorganic nano ceramic layer, so that the shuttle effect of polysulfide can be effectively inhibited.
Specifically, one of the main reasons for the occurrence of the shuttling effect is that the sulfur material in the lithium-sulfur battery has very poor conductivity, large polarization effect and unbalanced potential, thereby generating the shuttling effect. According to the invention, the three-dimensional conductive mesh structure is formed by matching the carbon nano tube and the conductive carbon black (and/or graphene), so that the diaphragm substrate has higher conductivity, the polarization effect is weakened, and the shuttle effect can be effectively inhibited. Meanwhile, the honeycomb network structure formed by the PE, the CNT and the conductive carbon black or the graphene has better adsorption effect on polysulfide, so that the shuttle of the polysulfide is further reduced. The matching and proportion control of the carbon nano tube and the conductive carbon black and/or the graphene are crucial to guarantee the effect of the diaphragm, the effect is best when the adding proportion of the carbon nano tube is 2-5% and the adding total amount of the conductive carbon black and the graphene is 5-10%, and meanwhile, the mechanical strength and the heat resistance of the diaphragm can be effectively improved. The diaphragm of the invention has the thickness of 5-40 μm, the air permeability of 50-10000 s/100cc, the puncture resistance of more than 50gf/μm, and the size shrinkage of the heat resistance of less than or equal to 5% under the condition of 105 ℃/h.
The coating of the inorganic nano ceramic layer comprises the following components in parts by weight: 0.2-5 parts of water-soluble polymer thickener, 0.2-5 parts of water-based dispersant, 17.6-45 parts of ceramic particles and 2-7 parts of water-based adhesive. The ceramic is one or a combination of more of silicon dioxide, aluminum oxide, boehmite, titanium dioxide, magnesium oxide, barium sulfate and molybdenum disulfide, and is preferably molybdenum disulfide of a flaky material (the inorganic ceramic coating is prepared by a flaky inorganic material to obtain a compact multilayer stacked result, so that shuttle of polysulfide is further inhibited); the water-based polymer thickener is one or a combination of more of hydroxyethyl cellulose, methyl hydroxyethyl cellulose and sodium carboxymethyl cellulose; the water-based dispersant is one or a combination of more of polyethylene glycol, polyacrylic acid, sodium polyacrylate and potassium polyacrylate; the water-based adhesive is one or a combination of a plurality of styrene-acrylic latex, styrene-butadiene latex, polymethyl methacrylate and polyethyl acrylate.
The preparation method of the high-performance lithium-sulfur battery diaphragm comprises the following steps:
firstly, melting, plasticizing and mixing ultra-high molecular weight polyethylene (with the molecular weight of 30-200 ten thousand), a pore-forming agent (paraffin oil, the adding proportion of which is 50% -70%), a carbon nano tube and conductive carbon black and/or graphene by a double-screw extruder to obtain a sheet, cooling the sheet by a sheet casting roller to form a membrane with the thickness of 500-1500 mu m, wherein the temperature of the sheet casting roller is 10-60 ℃, expanding holes of the obtained sheet by a two-way stretching (longitudinal and transverse) system and improving the mechanical strength to obtain a film with uniform thickness, washing out the paraffin oil by the film through solvent extraction, and shaping by shaping equipment to obtain the honeycomb-shaped porous diaphragm matrix. Wherein the longitudinal stretching magnification is 5-8 times, and the stretching temperature is 90-120 ℃; the transverse stretching rate is 6-9 times, the stretching temperature is 110-125 ℃, the shaping temperature is 120-135 ℃, the thickness of the obtained porous diaphragm substrate is 5-30 mu m, and the electric conductivity is not less than 10 -6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: uniformly stirring and mixing a water-soluble polymer thickener, a water-based dispersant and water to obtain a mixture 1; then adding the ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; and adding the aqueous adhesive into the mixture 2, and uniformly stirring to form the inorganic nano ceramic layer coating.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the thickness of the inorganic nano ceramic layer is 1-10 mu m, and the porosity of the inorganic nano ceramic layer is 50-80%.
The invention also optimizes the preparation process parameters of the diaphragm, such as stretching and shaping temperature, the composition and proportion of the inorganic nano ceramic layer coating, the coating thickness of the coating and the like, so that the mechanical strength, the heat resistance and the safety performance of the obtained diaphragm can be further improved on the basis of ensuring the shuttle effect inhibition effect, the performance uniformity of the obtained diaphragm is better, the normal performance of the lithium-sulfur battery is facilitated, meanwhile, the preparation process is simple, the cost is relatively lower, and the industrialized production is easy to realize.
The invention is further described with reference to specific examples.
Example 1
The preparation method of the high-performance lithium-sulfur battery diaphragm comprises the following steps:
step one, melting, plasticizing and mixing 20% of ultra-high molecular weight polyethylene, 70% of pore-forming agent paraffin oil, 3% of carbon nano tubes and 7% of conductive carbon black by a double-screw extruder to obtain a sheet, and then cooling the sheet by a sheet casting roller to form a membrane with the thickness of 500 mu m, wherein the temperature of the sheet casting roller is 10 ℃; and reaming the obtained sheet by a biaxial tension system and improving the mechanical strength to obtain a film with uniform thickness, extracting the film by a solvent, washing out paraffin oil, and shaping by a shaping device to obtain the honeycomb porous diaphragm matrix. Wherein the longitudinal stretching multiplying power is 5 times, and the stretching temperature is 90 ℃; the transverse stretching ratio is 9 times, the stretching temperature is 110 ℃, the shaping temperature is 120 ℃, the thickness of the obtained porous diaphragm substrate is 5 mu m, and the electric conductivity is not less than 10 - 6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: stirring and uniformly mixing 0.2 part of water-soluble polymer thickener, 0.2 part of water-based dispersant and water to obtain a mixture 1; then adding 18 parts of ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; and 2 parts of aqueous adhesive is added into the mixture 2, and the inorganic nano ceramic layer coating is formed after uniform stirring. The ceramic of this embodiment is molybdenum disulfide of a sheet material, the aqueous polymer thickener is hydroxyethyl cellulose, the aqueous dispersant is polyethylene glycol, and the aqueous binder is styrene-acrylic latex.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the thickness of the inorganic nano ceramic layer is 1 mu m, and the porosity of the inorganic nano ceramic layer is 50%.
Example 2
The preparation method of the high-performance lithium-sulfur battery separator of the embodiment comprises the following steps:
firstly, melting, plasticizing and mixing 40% of ultra-high molecular weight polyethylene, 50% of pore-forming agent paraffin oil, 5% of carbon nano tube and 5% of graphene by a double-screw extruder to obtain a sheet, and then cooling by a sheet casting roller to form a membrane with the thickness of 1000 mu m, wherein the temperature of the sheet casting roller is 25 ℃; and reaming the obtained sheet by a biaxial tension system and improving the mechanical strength to obtain a film with uniform thickness, extracting the film by a solvent, washing out paraffin oil, and shaping by a shaping device to obtain the honeycomb porous diaphragm matrix. Wherein the longitudinal stretching multiplying power is 7 times, and the stretching temperature is 95 ℃; the transverse stretching ratio is 8 times, the stretching temperature is 114 ℃, the shaping temperature is 122 ℃, the thickness of the obtained porous diaphragm substrate is 18 mu m, and the electric conductivity is not less than 10 -6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: stirring and uniformly mixing 3 parts of water-soluble polymer thickener, 2 parts of water-based dispersant and water to obtain a mixture 1; then adding 24 parts of ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; 4 parts of aqueous adhesive is added into the mixture 2, and the inorganic nano ceramic layer coating is formed after even stirring. The ceramic of the embodiment is aluminum oxide, the aqueous polymer thickener is methyl hydroxyethyl cellulose, the aqueous dispersant is sodium polyacrylate, and the aqueous binder is polymethyl methacrylate.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the inorganic nano ceramic layer is 5 microns in thickness and 70% in porosity.
Example 3
The preparation method of the high-performance lithium-sulfur battery separator of the embodiment comprises the following steps:
firstly, melting, plasticizing and mixing 30% of ultra-high molecular weight polyethylene, 58% of pore-forming agent paraffin oil, 2% of carbon nano tube and 10% of conductive carbon black and graphene by a double-screw extruder to obtain a sheet, and then cooling by a sheet casting roller to form a film with the thickness of 1500 mu m, wherein the temperature of the sheet casting roller is 40 ℃; and reaming the obtained sheet by a biaxial tension system and improving the mechanical strength to obtain a film with uniform thickness, extracting the film by a solvent, washing out paraffin oil, and shaping by a shaping device to obtain the honeycomb porous diaphragm matrix. Wherein the longitudinal stretching multiplying power is 8 times, and the stretching temperature is 120 ℃; the transverse stretching ratio is 6 times, the stretching temperature is 125 ℃, the shaping temperature is 130 ℃, the thickness of the obtained porous diaphragm substrate is 30 mu m, and the electric conductivity is not less than 10 -6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: stirring and uniformly mixing 5 parts of water-soluble polymer thickener, 5 parts of water-based dispersant and water to obtain a mixture 1; then adding 45 parts of ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; and 7 parts of aqueous adhesive is added into the mixture 2, and the inorganic nano ceramic layer coating is formed after uniform stirring. The ceramic of this embodiment is a combination of silicon dioxide, aluminum oxide, and boehmite, the aqueous polymer thickener is a combination of methylhydroxyethyl cellulose and sodium carboxymethyl cellulose, the aqueous dispersant is a combination of polyacrylic acid and potassium polyacrylate, and the aqueous binder is a combination of styrene-butadiene latex and polyethylacrylate.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the inorganic nano ceramic layer is 10 microns in thickness and 65% in porosity.
Example 4
The preparation method of the high-performance lithium-sulfur battery separator of the embodiment comprises the following steps:
firstly, melting, plasticizing and mixing 34% of ultra-high molecular weight polyethylene, 65% of pore-forming agent paraffin oil, 0.5% of carbon nano tube and 0.5% of conductive carbon black by a double-screw extruder to obtain a sheet, and then cooling by a sheet casting roller to form a membrane with the thickness of 700 mu m, wherein the temperature of the sheet casting roller is 60 ℃; and reaming the obtained sheet by a biaxial tension system and improving the mechanical strength to obtain a film with uniform thickness, extracting the film by a solvent, washing out paraffin oil, and shaping by a shaping device to obtain the honeycomb porous diaphragm matrix. Wherein the longitudinal stretching magnification is 6 times, and the stretching temperature is 114 ℃; the transverse stretching ratio is 7 times, the stretching temperature is 122 ℃, the shaping temperature is 125 ℃, the thickness of the obtained porous diaphragm substrate is 10 mu m, and the electric conductivity is not less than 10 -6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: stirring and uniformly mixing 2 parts of water-soluble polymer thickener, 3 parts of water-based dispersant and water to obtain a mixture 1; then adding 30 parts of ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; 4 parts of aqueous adhesive is added into the mixture 2, and the inorganic nano ceramic layer coating is formed after even stirring. The ceramic of this example is a combination of titanium dioxide and magnesium oxide, the aqueous polymeric thickener is sodium carboxymethylcellulose, the aqueous dispersant is potassium polyacrylate, and the aqueous binder is polyethylacrylate.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the inorganic nano ceramic layer is 4 microns in thickness and 60% in porosity.
Example 5
The preparation method of the high-performance lithium-sulfur battery separator of the embodiment comprises the following steps:
step one, melting, plasticizing and mixing 27% of ultra-high molecular weight polyethylene, 60% of pore-forming agent paraffin oil, 10% of carbon nano tube and 3% of conductive carbon black and graphene by a double-screw extruderExtruding to obtain a sheet, cooling by a sheet casting roller to form a film with the thickness of 1200 mu m, wherein the temperature of the sheet casting roller is 35 ℃; and reaming the obtained sheet by a biaxial tension system and improving the mechanical strength to obtain a film with uniform thickness, extracting the film by a solvent, washing out paraffin oil, and shaping by a shaping device to obtain the honeycomb porous diaphragm matrix. Wherein the longitudinal stretching multiplying power is 6 times, and the stretching temperature is 98 ℃; the transverse stretching ratio is 6 times, the stretching temperature is 117 ℃, the shaping temperature is 135 ℃, the thickness of the obtained porous diaphragm substrate is 22 mu m, and the electric conductivity is not less than 10 -6 S/cm。
Step two, preparing the inorganic nano ceramic layer coating: 1 part of water-soluble polymer thickener, 1.5 parts of water-based dispersant and water are stirred and mixed uniformly to obtain a mixture 1; then adding 25 parts of ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; 3 parts of aqueous adhesive is added into the mixture 2, and the inorganic nano ceramic layer coating is formed after even stirring. The ceramic of this embodiment is a combination of titanium dioxide and magnesium oxide, the aqueous polymer thickener is a combination of hydroxyethyl cellulose, methyl hydroxyethyl cellulose, and sodium carboxymethyl cellulose, the aqueous dispersant is a combination of polyethylene glycol, sodium polyacrylate, and potassium polyacrylate, and the aqueous binder is styrene-butadiene latex.
And step three, coating or compounding the inorganic nano ceramic layer coating on the surface of the porous diaphragm substrate in a micro-concave coating, dip coating or transfer coating mode and the like to obtain the high-performance lithium-sulfur battery diaphragm, wherein the inorganic nano ceramic layer is 8 microns in thickness and 80% in porosity.
Claims (6)
1. A preparation method of a high-performance lithium-sulfur battery diaphragm is characterized by comprising the following steps: blending and modifying polyethylene, carbon nano tubes, conductive carbon black and graphene by an extruder, and then preparing a cellular porous diaphragm matrix by biaxial tension and extraction; coating or compounding an inorganic nano ceramic layer on the surface of the porous diaphragm substrate to obtain the high-performance lithium-sulfur battery diaphragm; the high-performance lithium-sulfur battery diaphragm comprises a porous diaphragm matrix, and the preparation raw materials of the porous diaphragm matrix comprise the following components in percentage by mass: 20-40% of polyethylene, 2-5% of carbon nano tube, 5-10% of conductive carbon black and graphene; the porous diaphragm matrix is a honeycomb three-dimensional mesh porous membrane with certain conductivity, wherein the carbon nano tubes are distributed along the thickness direction of the diaphragm, the conductive carbon black and the graphene are distributed along the plane direction of the diaphragm, and the carbon nano tubes, the conductive carbon black and the graphene form a three-dimensional network conductor; and an inorganic nano ceramic layer is arranged on the surface of the porous diaphragm substrate.
2. The method for preparing a high-performance lithium-sulfur battery separator according to claim 1, wherein: the thickness of the porous diaphragm substrate is 5-30 mu m, and the electric conductivity of the porous diaphragm substrate is not less than 10 -6 S/cm, the thickness of the inorganic nano ceramic layer is 1-10 mu m, and the porosity is 50-80%; the ceramic is one or a combination of more of silicon dioxide, aluminum oxide, boehmite, titanium dioxide, magnesium oxide, barium sulfate and molybdenum disulfide.
3. The method for preparing a high-performance lithium-sulfur battery separator according to claim 1, wherein: the coating of the inorganic nano ceramic layer comprises the following components in parts by weight: 0.2-5 parts of water-soluble polymer thickener, 0.2-5 parts of water-based dispersant, 17.6-45 parts of ceramic particles and 2-7 parts of water-based adhesive.
4. The method for preparing a high-performance lithium-sulfur battery separator according to claim 3, wherein: the water-based polymer thickener is one or a combination of more of hydroxyethyl cellulose, methyl hydroxyethyl cellulose and sodium carboxymethyl cellulose; the water-based dispersant is one or a combination of more of polyethylene glycol, polyacrylic acid, sodium polyacrylate and potassium polyacrylate; the water-based adhesive is one or a combination of a plurality of styrene-acrylic latex, styrene-butadiene latex, polymethyl methacrylate and polyethyl acrylate.
5. The method for preparing the high-performance lithium-sulfur battery separator according to any one of claims 1 to 4, wherein the longitudinal stretching ratio in the biaxial stretching is 5 to 8 times, and the stretching temperature is 90 to 120 ℃; the transverse stretching rate is 6-9 times, and the stretching temperature is 110-125 ℃; the preparation process of the coating of the inorganic nano ceramic layer comprises the following steps: uniformly stirring and mixing a water-soluble polymer thickener, a water-based dispersant and water to obtain a mixture 1; then adding the ceramic particles into the mixture 1, continuously stirring and uniformly dispersing to obtain a mixture 2; and adding the aqueous adhesive into the mixture 2, and uniformly stirring to form the inorganic nano ceramic layer coating.
6. Use of the separator prepared by the method according to any one of claims 1 to 5 in a lithium-sulfur battery.
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| CN112072075A (en) * | 2020-09-02 | 2020-12-11 | 昆山宝创新能源科技有限公司 | Negative electrode film and preparation method and application thereof |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102315406A (en) * | 2010-06-30 | 2012-01-11 | 比亚迪股份有限公司 | Nickel-hydrogen battery diaphragm, and preparation method and nickel-hydrogen battery thereof |
| CN103618059A (en) * | 2013-12-10 | 2014-03-05 | 深圳市星源材质科技有限公司 | Lithium ion battery diaphragm with polymer inorganic coating and preparation method for lithium ion battery diaphragm |
| CN105140447A (en) * | 2015-07-23 | 2015-12-09 | 中国科学院上海硅酸盐研究所 | Functional composite membrane for lithium-sulfur battery and preparation method of functional composite membrane |
| CN108091878A (en) * | 2017-12-05 | 2018-05-29 | 四川华昆能源有限责任公司 | A kind of preparation method of lithium-sulfur cell graphene carbon nanotube composite conducting skeleton |
| CN108258176A (en) * | 2017-12-29 | 2018-07-06 | 成都市银隆新能源有限公司 | A kind of lithium battery diaphragm |
| CN108539265A (en) * | 2017-03-02 | 2018-09-14 | 深圳格林德能源有限公司 | A kind of lithium-sulfur cell |
| CN109103492A (en) * | 2018-09-03 | 2018-12-28 | 江西克莱威纳米碳材料有限公司 | Hydroxyapatite nanowire-carbon nanotube film, preparation method thereof and lithium-sulfur battery |
| CN109216631A (en) * | 2018-09-14 | 2019-01-15 | 力信（江苏）能源科技有限责任公司 | A kind of high security lithium ion battery composite diaphragm and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9373829B2 (en) * | 2013-10-11 | 2016-06-21 | GM Global Technology Operations LLC | Porous interlayer for a lithium-sulfur battery |
-
2019
- 2019-12-02 CN CN201911213813.8A patent/CN110854345B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102315406A (en) * | 2010-06-30 | 2012-01-11 | 比亚迪股份有限公司 | Nickel-hydrogen battery diaphragm, and preparation method and nickel-hydrogen battery thereof |
| CN103618059A (en) * | 2013-12-10 | 2014-03-05 | 深圳市星源材质科技有限公司 | Lithium ion battery diaphragm with polymer inorganic coating and preparation method for lithium ion battery diaphragm |
| CN105140447A (en) * | 2015-07-23 | 2015-12-09 | 中国科学院上海硅酸盐研究所 | Functional composite membrane for lithium-sulfur battery and preparation method of functional composite membrane |
| CN108539265A (en) * | 2017-03-02 | 2018-09-14 | 深圳格林德能源有限公司 | A kind of lithium-sulfur cell |
| CN108091878A (en) * | 2017-12-05 | 2018-05-29 | 四川华昆能源有限责任公司 | A kind of preparation method of lithium-sulfur cell graphene carbon nanotube composite conducting skeleton |
| CN108258176A (en) * | 2017-12-29 | 2018-07-06 | 成都市银隆新能源有限公司 | A kind of lithium battery diaphragm |
| CN109103492A (en) * | 2018-09-03 | 2018-12-28 | 江西克莱威纳米碳材料有限公司 | Hydroxyapatite nanowire-carbon nanotube film, preparation method thereof and lithium-sulfur battery |
| CN109216631A (en) * | 2018-09-14 | 2019-01-15 | 力信（江苏）能源科技有限责任公司 | A kind of high security lithium ion battery composite diaphragm and preparation method thereof |
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