CN112968158B - Organic silicon sulfur positive electrode material, preparation method thereof, positive electrode piece and lithium sulfur battery - Google Patents
Organic silicon sulfur positive electrode material, preparation method thereof, positive electrode piece and lithium sulfur battery Download PDFInfo
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Abstract
The invention discloses an organic silicon sulfur positive electrode material and a preparation method thereof, a positive electrode piece and a lithium sulfur battery, wherein the preparation method of the organic silicon sulfur positive electrode material comprises the following steps: polysulfide is dissolved in an organic solvent, and then halogenated siloxane is added to react at the temperature of 150-250 ℃; then the temperature is reduced to 50-100 ℃, alkali liquor is added for hydrolysis condensation reaction, and then the product is washed and dried to obtain the catalyst. The preparation method of the organic silicon sulfur positive electrode material is simple in process, the nano-structure coated sulfur is formed by hydrolytic condensation between siloxane, and the organic silicon sulfur positive electrode material is connected with sulfur through chemical bonds, so that the dissolution and shuttling phenomena of polysulfide in the circulating process are further reduced, the prepared organic silicon sulfur positive electrode material can be used as a positive electrode material of a lithium sulfur battery, and the circulating stability of the lithium sulfur battery can be improved.
Description
Technical Field
The invention relates to the technical field of battery positive electrode materials, in particular to an organic silicon-sulfur positive electrode material and a preparation method thereof, a positive electrode piece and a lithium-sulfur battery.
Background
At present, the specific capacity of the positive electrode material based on nickel and cobalt oxide is low (less than 250mAh g) -1 ) Meanwhile, nickel and cobalt resources are in short supply, and the environmental toxicity is high, so that the traditional commercial lithium ion battery has the defects of low energy density, high cost, high environmental toxicity and the like. The research and development of a new generation of low-toxicity, low-cost, long-life, high-capacity and high-energy density lithium ion battery and key materials thereof have always been an important direction for developing electrochemical energy storage and nano energy materials.
The lithium-sulfur battery system has the advantages of high energy density, low cost and the like as a novel secondary battery system. One of the problems to be solved in order to realize the practical application of lithium-sulfur batteries is the "shuttling effect" of polysulfides. In the process of discharging the lithium sulfur battery, the nanocarbon material with a non-polar surface is used as the positive electrode of the lithium sulfur battery, and sufficient surface binding force and limiting effect are hardly provided for the polar polysulfide, so that the polysulfide is dissolved and diffused to the surface of the negative electrode to react, and loss of active substances and capacity attenuation are caused.
In recent years, researchers have achieved a series of innovative academic achievements in overcoming the scientific problems of dissolution and shuttling of active substances, SEI (solid electrolyte interphase) of electrode interfaces and the like in the circulation process of the materials. Most of the work is focused on the construction of a micro-nano structure of a lithium-sulfur battery anode material/electrode, and complex porous carbon (doping modification) and nano metal sulfide, oxide, nitride, hydroxide and the like are mainly adopted as carriers to overcome the dissolution and shuttling of polysulfide in the circulating process so as to improve the circulating and multiplying power performance. For example:
compared with the corresponding block or nano particles, the metal oxide micro nano tube added in the positive electrode material has high porosity, large specific surface area and large aperture, can better inhibit the dissolution of polysulfide and maintain the charging and discharging stability of the lithium sulfur battery.
In addition, an active substance layer composed of aluminum, porous carbon and sulfur and a current collector are fused and cast to be compounded, the aluminum in the active substance layer forms a conductive metal network, the porous carbon is used for filling sulfur, and the conductivity and the structural stability of the obtained lithium-sulfur battery anode are greatly improved compared with those of the conventional lithium-sulfur battery anode, so that the rate capability and the cycle performance of the lithium-sulfur battery are effectively improved.
The composite carbon material containing the three-dimensional interpenetrating network is formed by interpenetrating the inside of a carbon nano tube and a ZIF-67 derived hierarchical pore carbon polyhedron, the activated carbon nano tube is used as a framework, ZIF-67 grows on the surface of the activated carbon nano tube, the ZIF-67 is carbonized into the hierarchical pore carbon polyhedron through high-temperature sintering, the hierarchical pore carbon polyhedron is compounded with elemental sulfur in a CS2 solution, the mixture is stirred until the solvent is completely volatilized, the elemental sulfur in the mixture is infiltrated into the carbon structure by adopting a melting method, and finally the lithium sulfur battery anode material containing the three-dimensional interpenetrating composite carbon material is prepared.
The method prepares the lithium-sulfur battery anode material by carbon coating or filling, has great process difficulty, and the prepared lithium-sulfur battery anode material can not completely inhibit polysulfide dissolution and shuttling phenomena in the battery cycle process, so the battery cycle and rate capability are still poor.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides an organic silicon sulfur positive electrode material, a preparation method thereof, a positive electrode piece and a lithium sulfur battery.
In a first aspect of the present invention, a preparation method of an organosilicon sulfur cathode material is provided, which comprises the following steps:
s1, polysulfide is dissolved in an organic solvent, and then halogenated siloxane is added to react at the temperature of 150-250 ℃;
and S2, reducing the temperature of the materials reacted in the step S1 to 50-100 ℃, adding alkali liquor to perform a hydrolytic condensation reaction, and washing and drying the product.
The preparation method of the organic silicon-sulfur cathode material provided by the embodiment of the invention has at least the following beneficial effects: the preparation method comprises the steps of taking polysulfide and halogenated siloxane as raw materials to react, carrying out hydrolysis condensation reaction on reaction products in an alkaline environment, and forming a nano-framework structure by utilizing silicon-oxygen bonds and carbon-sulfur bonds for crosslinking; the silicon-oxygen bond has high energy and certain flexibility, can well protect the sulfur active material, and improves the stability in the circulating process; the carbon-sulfur bond can lock polysulfide through chemical bond, further reducing the dissolution and shuttling phenomena of polysulfide in the circulating process. According to the preparation method of the organic silicon sulfur positive electrode material, the process is simple, the nano-structure coated sulfur is formed by hydrolysis and condensation of siloxane, the organic silicon sulfur positive electrode material is connected with sulfur through chemical bonds, the dissolution and shuttling phenomena of polysulfide in the circulating process are further reduced, the prepared organic silicon sulfur positive electrode material can be used as a positive electrode material of a lithium sulfur battery, and the circulating stability of the lithium sulfur battery can be further improved.
According to some embodiments of the invention, in step S1, the polysulfide is selected from at least one of sodium polysulfide and potassium polysulfide.
According to some embodiments of the invention, the sodium polysulfide has the formula Na 2 S n Wherein n is an integer of 1 to 8.
According to some embodiments of the invention, in step S1, the halosiloxane has the formula:
wherein R is 1 、R 2 Each independently selected from alkoxy or alkyl substituted or unsubstituted with a halogen atom; r is 3 Selected from alkoxy or alkyl substituted by halogen atoms; r 4 Selected from alkoxy groups.
According to some embodiments of the invention, R 1 、R 2 Each independently selected from alkoxy or alkyl groups, which are terminally substituted or unsubstituted by halogen atoms; r 3 Selected from alkoxy or alkyl groups substituted at the end of the halogen atom. Further, R 1 、R 2 Each independently selected from C1-C3 alkoxy or alkyl groups substituted or unsubstituted at the end of a halogen atom; r 3 Selected from C1-C3 alkoxy or alkyl substituted at the end of halogen atom.
According to some embodiments of the invention, the halogenated siloxane is a chlorosiloxane. For example, if sodium polysulfide (Na) is used as polysulfide 2 S n ) (ii) a The halogenated siloxane is selected from the group consisting of materials of the following structures:
wherein R is 1 、R 2 Each independently selected from alkoxy or alkyl substituted or unsubstituted with chlorine; r is 3 ' is selected from-OR-OR alkylene, R is alkylene; r 4 ' is selected from alkyl; the alkali liquor in the step S2 can be NaOH, and the reaction equation of the preparation process of the organic silicon sulfur cathode material is as follows:
(ii) a Wherein R is 1 、R 2 Each independently selected from alkoxy or alkyl substituted or unsubstituted with chlorine; r 3 ' is selected from-OR-OR alkylene, R is alkylene; r is 4 ' is selected from alkyl groups, and n is generally an integer from 1 to 8.
According to some embodiments of the invention, the halosiloxane is selected from at least one of 3-chloropropyltriethoxysilane, (chloromethyl) trimethoxysilane, bis (chloromethyl) dimethoxysilane, tris (chloromethyl) methoxysilane.
According to some embodiments of the invention, in step S1, the molar ratio of the polysulfide to the halosiloxane is 1: (1-10).
According to some embodiments of the invention, in step S1, the reaction time is greater than 4h; and/or in the step S2, the time of the hydrolytic condensation reaction is more than 12h. In addition, in step S1, at least one of ethanol, methanol and isopropanol can be used as the organic solvent; in step S2, alkali liquor is added to provide an alkaline environment for the hydrolysis condensation reaction, and the alkali liquor can specifically adopt sodium hydroxide, potassium hydroxide and the like.
In a second aspect of the present invention, an organosilicon sulfur cathode material is provided, which is prepared by any one of the preparation methods of the organosilicon sulfur cathode material provided in the first aspect of the present invention. The organic silicon sulfur anode material comprises the following materials with the structural formula:
wherein R is 1 、R 2 Each independently selected from alkoxy or alkyl substituted or unsubstituted with halogen atoms; r 3 ' is selected from-OR-OR alkylene, R is alkylene; r is 4 ' is selected from alkyl, and n is an integer of 1 to 8.
In a third aspect of the invention, a positive electrode plate is provided, which includes a current collector and a positive electrode material layer coated on the current collector, and the material of the positive electrode material layer includes any one of the organosilicon sulfur positive electrode materials provided in the second aspect of the invention.
In a fourth aspect of the invention, a lithium-sulfur battery is provided, which comprises any one of the positive electrode plates provided in the third aspect of the invention.
Drawings
The invention is further described with reference to the following figures and examples, in which:
FIG. 1 is an SEM image of an organosilicon sulfur cathode material of example 1 of the present invention;
FIG. 2 is an EDS diagram of an organosilicon sulfur positive electrode material according to example 1 of the present invention;
fig. 3 is a schematic discharge capacity 200 times before constant current charge-discharge cycle test at 0.5C rate of button cell C1# prepared by using the organic silicon sulfur positive electrode material in example 1;
fig. 4 is a schematic discharge capacity diagram of a button cell C1# prepared by using the organosilicon sulfur positive electrode material of example 1 in a constant current charge-discharge cycle test under different multiplying factors.
Detailed Description
The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.
Example 1
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then 0.03mol3-chloropropyltriethoxysilane (structural formula:
) (ii) a Then placing the solution in a water bath environment at 175 ℃ to be stirred and reacted for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon sulfur cathode material.
When the organosilicon sulfur cathode material prepared in this example was observed by a Scanning Electron Microscope (SEM), the obtained result is shown in fig. 1, and it can be seen that the prepared organosilicon sulfur cathode material is a spherical nanomaterial with a particle size of about 20-50 nm, and has a small size. In addition, the organosilicon sulfur positive electrode material prepared in this example was analyzed by an X-ray energy spectrometer (EDS), and the results are shown in fig. 2, and the test results show that the prepared material contains S, O, si, C, etc., which proves that the material contains siloxane and sulfur, and the expected reaction results are the same.
Example 2
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then adding 0.01mol3-chloropropyltriethoxysilane into the solution; then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, cooling the water bath temperature to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolytic condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon sulfur cathode material.
Example 3
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then 0.1mol L3-chloropropyltriethoxysilane is added into the solution; then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, cooling the water bath temperature to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolytic condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon sulfur cathode material.
Example 4
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, adding 0.01moL of tetrasulfideDissolving sodium (Na) 2 S 4 ) Dissolving in 100mL of ethanol; then 0.03mol3-chloropropyltriethoxysilane is added into the solution; then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
Example 5
The preparation method of the organic silicon sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium sulfide (Na) 2 S) dissolving in 100mL of ethanol; then 0.03mol of 3-chloropropyltriethoxysilane is added into the solution; then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
Example 6
The preparation method of the organic silicon sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then 0.03moL (chloromethyl) trimethoxysilane (formula:
) (ii) a Then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
Example 7
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, adding 0.01moL sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL ethanol; then, 0.03moL of bis (chloromethyl) dimethoxysilane (structural formula:
) (ii) a Then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
Example 8
The preparation method of the organic silicon sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL ethanol; then 0.03moL of tris (chloromethyl) methoxysilane (having the structural formula:
) (ii) a Then placing the solution in a water bath environment at 175 ℃ to be stirred and react for 6 hours;
s2, cooling the water bath temperature to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolytic condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
Example 9
The preparation method of the organic silicon sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then 0.03mol3-chloropropyltriethoxysilane is added into the solution; then placing the solution in a water bath environment at 150 ℃ to be stirred and react for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon sulfur cathode material.
Example 10
The preparation method of the organic silicon-sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL ethanol; then 0.03mol3-chloropropyltriethoxysilane is added into the solution; then placing the solution in a water bath environment at 250 ℃ to be stirred and react for 6 hours;
s2, cooling the water bath temperature to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolytic condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon sulfur cathode material.
Comparative example 1
The preparation method of the organic silicon sulfur cathode material comprises the following steps:
s1, mixing 0.01moL of sodium octasulfide (Na) 2 S 8 ) Dissolving in 100mL of ethanol; then 0.03moL of tetrachlorosilane is added into the solution; then placing the solution in a water bath environment at 175 ℃ to be stirred and reacted for 6 hours;
s2, reducing the temperature of the water bath to 100 ℃, adding 0.06moL of sodium hydroxide, and carrying out hydrolysis condensation reaction for 12 hours under the stirring condition; and after the reaction is cooled, repeatedly washing the product by using deionized water and ethanol, and drying to obtain the organic silicon-sulfur cathode material.
The organic silicon sulfur positive electrode material prepared by the method can be used as a positive electrode material of a battery to prepare a positive electrode plate, and further used for preparing a lithium sulfur battery. For example, the organosilicon sulfur positive electrode materials prepared in the above examples 1 to 10 and comparative example 1 can be used to prepare a positive electrode sheet, and then prepare a CR2032 type button lithium sulfur battery. Specifically, the organosilicon sulfur positive electrode material, acetylene black and hydroxymethyl cellulose are mixed in an N-methyl pyrrolidone solution according to the mass ratio of 85. The negative pole piece can adopt a metal lithium piece, and the electrolyte is LiPF with the concentration of 1mol/L 6 The solvent was dissolved in a mixture of Ethylene Carbonate (EC), dimethyl carbonate (DMC) and Ethyl Methyl Carbonate (EMC) (volume ratio 1.
The organic silicon sulfur positive electrode materials of the above examples 1-10 and the comparative example 1 are adopted to prepare button lithium sulfur batteries C1-C11 according to the method, and then electrochemical performance tests are carried out on the batteries. Specifically, each battery was charged and discharged at constant current at a rate of 0.5C and 1C, respectively, at room temperature. Wherein, the charge and discharge capacity and the first effect of the battery are tested under 0.5C multiplying power, the multiplying power performance is tested under 1C multiplying power, the voltage range is 1.6-2.8V, and the obtained results are shown in Table 1.
TABLE 1 electrochemical Performance test results for each button cell
From the above, comparing the battery C1# to C3# (adopting the organic silicon sulfur positive electrode materials of examples 1 to 3 respectively) and the performance test results thereof, it can be known that the usage amount of the halogenated siloxane (3-chloropropyltriethoxysilane) is reduced, and the overall rate performance of the battery can be improved; the amount of the halogenated siloxane (3-chloropropyltriethoxysilane) is increased, so that the overall cycle performance of the battery can be improved. This is because, by reducing the amount of halogenated siloxane, the protective framework of the siloxane is reduced, and the sulfur embedded therein is more accessible to electrons and ions, and therefore the rate capability is improved; and the amount of the halogenated siloxane is increased, the protective structure is denser, the shuttle effect of polysulfide is weakened, and the cycle performance is better.
The results of comparing batteries C1#, C4# and C5# (using the organosilicon sulfur positive electrode materials of examples 1, 4 and 5 respectively) and performance tests thereof show that sodium polysulfide (Na) 2 S n ) The lower the value of n, the better the cycling performance of the cell, since the lower the sulfur content and the lower the discharge capacity, the better the protection of the sulfur by the protective framework of silicone and the better the cycling performance of the cell.
Comparing batteries C6#, C7# and C8# (adopting the organosilicon sulfur positive electrode materials of examples 6, 7 and 8 respectively) and performance test results thereof, it can be known that increasing the chlorine content in the chlorosiloxane has little effect on the first effect of the battery, but can improve the rate capability of the battery. An increase in the amount of chlorine results in an increase in the number of polysulfide bonds attached to the siloxane monomer structure, i.e., a decrease in the amount of siloxane attached to the polysulfide bonds, which makes the structure more porous and easier to charge transfer, and thus an increase in rate capability.
Comparing the batteries C9# and C10# (using the organosilicon sulfur positive electrode materials of examples 9 and 10, respectively) and the performance test results thereof, it can be seen that in step S1, the reaction can be performed normally at a water bath temperature of 150 to 250 ℃, and the implosion and gelation phenomena can be avoided.
As can be seen from the battery C11# (using the organosilicon sulfur positive electrode material of comparative example 1) and the electrochemical performance test results thereof, the cycle performance of the battery was seriously deteriorated without the protection of siloxane, which shows that the organosilicon sulfur positive electrode material of each example of the present invention can well inhibit the dissolution and shuttling effects of polysulfides.
Specifically, a constant current charge-discharge cycle test was performed at room temperature at a rate of 0.5C on a button cell C1# prepared by using the organic silicon-sulfur positive electrode material of example 1, wherein the voltage range was 1.6-2.8V, and a schematic diagram of the discharge capacity obtained in the previous 200 times is shown in fig. 3. The test shows that the battery discharge capacity of the battery C1# after 200 cycles is 828mAh/g, the capacity retention rate is 95.8%, and the battery has better cycle stability.
In addition, the battery C1# is subjected to constant current charge and discharge cycle tests under different multiplying factors (discharge current densities of 0.2, 0.5, 1.0, 2.0 and 5.0C) at normal temperature, and the discharge voltage range is 1.6-2.8V. The results of the test are shown in FIG. 4. Tests show that under the current densities of 0.2C, 0.5C, 1.0C, 2.0C and 5.0C, the discharge capacities are 978mAh/g, 864mAh/g, 723mAh/g, 634mAh/g and 413mAh/g respectively.
As can be seen from the above, the lithium-sulfur battery assembled by the organosilicon sulfur nanomaterial of example 1 has higher capacity, better cycling stability and rate capability.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.
Claims (10)
1. The preparation method of the organic silicon sulfur cathode material is characterized by comprising the following steps of:
s1, dissolving polysulfide in an organic solvent, adding halogenated siloxane, and reacting at 150 to 250 ℃; the structural formula of the halogenated siloxane is as follows:
(ii) a Wherein R is 1 Selected from halogen atoms substituted or unsubstituted alkoxy or alkyl radicals, R 2 Selected from alkoxy or alkyl substituted by halogen atoms; r is 3 Selected from alkoxy or alkyl substituted by halogen atoms; r is 4 Is selected from alkoxy;
s2, cooling the temperature of the material after the reaction in the step S1 to 50-100 ℃, adding an alkali liquor to carry out a hydrolytic condensation reaction, washing and drying the product to obtain the organic silicon-sulfur positive electrode material; the organic silicon sulfur positive electrode material is a spherical nano material with a nano framework structure, and the nano framework structure is coated with sulfur and is connected with the sulfur through a chemical bond to lock polysulfide.
2. The method of preparing the positive electrode material of claim 1, wherein in step S1, the polysulfide is at least one selected from the group consisting of sodium polysulfide and potassium polysulfide.
3. The method of claim 2, wherein the sodium polysulfide has a formula of Na 2 S n Wherein n is an integer of 1 to 8.
4. The method for producing the organosilicon sulfur positive electrode material according to claim 1, wherein R is 1 、R 2 Each independently selected from alkoxy or alkyl substituted by halogen atoms; r 3 Selected from alkoxy or alkyl substituted by halogen atoms; r is 4 Selected from alkoxy groups.
5. The method for producing the organosilicon sulfur positive electrode material according to claim 1, wherein R is 1 Selected from the group consisting of alkoxy or alkyl groups, unsubstituted or substituted at the end of the halogen atom, R 2 Selected from alkoxy or alkyl groups substituted at the end of the halogen atom; r is 3 Selected from alkoxy or alkyl groups substituted at the end of the halogen atom.
6. The method for producing the organosilicon sulfur positive electrode material according to claim 5, wherein the halogenated siloxane is a chlorosiloxane; the halogenated siloxane is at least one selected from bis (chloromethyl) dimethoxysilane and tris (chloromethyl) methoxysilane.
7. The method for producing the silicone sulfur positive electrode material according to claim 1, wherein in step S1, the molar ratio of the polysulfide to the halosiloxane is 1: (1 to 10).
8. An organosilicon sulfur positive electrode material, characterized by being produced by the method for producing an organosilicon sulfur positive electrode material according to any one of claims 1 to 7.
9. A positive pole piece, which is characterized by comprising a current collector and a positive pole material layer coated on the current collector, wherein the material of the positive pole material layer comprises the organosilicon sulfur positive pole material according to claim 8.
10. A lithium-sulfur battery comprising the positive electrode sheet according to claim 9.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105702960A (en) * | 2014-11-25 | 2016-06-22 | 江苏合志锂硫电池技术有限公司 | Composite binder, lithium secondary battery positive electrode using composite binder, and making method of positive electrode |
| JP2016177980A (en) * | 2015-03-20 | 2016-10-06 | コニカミノルタ株式会社 | Positive electrode material for battery and all-solid lithium ion battery |
| WO2020016174A1 (en) * | 2018-07-19 | 2020-01-23 | Shell Internationale Research Maatschappij B.V. | Process for preparing sulfur containing organosilane polymers |
| CN110892561A (en) * | 2017-07-25 | 2020-03-17 | 国际壳牌研究有限公司 | Electric energy storage device |
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| DE10351736B3 (en) * | 2003-11-06 | 2005-01-13 | Degussa Ag | Preparation of (mercaptoorganyl)alkoxysilanes comprises reacting alkali metal sulfide with mixture of (haloorganyl)alkoxysilane and (haloorganyl)halosilane in alcohol with exclusion of air and at elevated pressure |
| CN104448321B (en) * | 2013-09-18 | 2017-02-15 | 中国石油化工股份有限公司 | Modified ordered mesoporous organosilicon material, preparation method and application thereof |
| CN104716297B (en) * | 2013-12-15 | 2017-02-15 | 中国科学院大连化学物理研究所 | Oleophylic sulfur electrode preparation method |
| KR102326642B1 (en) * | 2019-03-19 | 2021-11-16 | 전남대학교산학협력단 | Cathode for lithium-sulfur battery comprising siloxene compound |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105702960A (en) * | 2014-11-25 | 2016-06-22 | 江苏合志锂硫电池技术有限公司 | Composite binder, lithium secondary battery positive electrode using composite binder, and making method of positive electrode |
| JP2016177980A (en) * | 2015-03-20 | 2016-10-06 | コニカミノルタ株式会社 | Positive electrode material for battery and all-solid lithium ion battery |
| CN110892561A (en) * | 2017-07-25 | 2020-03-17 | 国际壳牌研究有限公司 | Electric energy storage device |
| WO2020016174A1 (en) * | 2018-07-19 | 2020-01-23 | Shell Internationale Research Maatschappij B.V. | Process for preparing sulfur containing organosilane polymers |
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