CN108987714B - Lithium-sulfur battery positive electrode active material and preparation method thereof, lithium-sulfur battery positive electrode material and lithium-sulfur battery - Google Patents
Lithium-sulfur battery positive electrode active material and preparation method thereof, lithium-sulfur battery positive electrode material and lithium-sulfur battery Download PDFInfo
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- H—ELECTRICITY
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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
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
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Abstract
The invention provides a lithium-sulfur battery positive electrode active material and a preparation method thereof, a lithium-sulfur battery positive electrode material and a lithium-sulfur battery. Relates to the technical field of battery materials, the anode active material comprises lithium sulfide and a carbon material doped with sulfur element which are connected in a sintering way, and the existing Li adopted is relieved2S/Metal oxide or Li2When the S/carbon composite material is used as the anode active material of the lithium-sulfur battery, the lithium-sulfur battery has poor cycle stability. According to the invention, the carbon material phase with the sulfur element doped in the lithium sulfide is compounded, so that the conductivity of the lithium sulfide can be obviously improved, and meanwhile, the carbon material phase with the sulfur element doped in the lithium sulfide can provide a binding site for polysulfide and improve the binding force between the polysulfide and the positive active material, so that the lithium-sulfur battery can keep higher specific capacity, and the cycle stability is obviously improved.
Description
Technical Field
The invention relates to the technical field of battery materials, in particular to a lithium-sulfur battery positive electrode active material and a preparation method thereof, a lithium-sulfur battery positive electrode material and a lithium-sulfur battery.
Background
The lithium-sulfur battery is a battery in which sulfur is used as a positive electrode active material and lithium metal is used as a negative electrode. Sulfur is an element with high abundance on the earth, has the characteristics of low cost and high energy density, the theoretical energy density reaches 1675mAh/g, and Li is finally generated after the sulfur is completely discharged2And S. In recent years, Li has been used2S is widely researched for the positive active material of the lithium-sulfur battery, and the theoretical capacity of the S reaches 1166 mAh/g. However, Li2S also has the defects of poor conductivity, poor cycle performance of the lithium-sulfur battery and the like because lithium polysulfide generated in the charging and discharging process is easy to dissolve in electrolyte.
In the prior art, Li is adopted2S/Metal oxide, Li2The S/carbon composite material serving as the positive active material of the lithium-sulfur battery has certain improvement on the comprehensive performance of the lithium-sulfur battery, but still exists in lithium sulfide and in the charging and discharging processesThe weak binding force of the generated lithium polysulfide limits the improvement of the cycle performance of the lithium-sulfur battery.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
One of the objectives of the present invention is to provide a method for preparing a positive electrode active material of a lithium-sulfur battery, so as to alleviate the existing Li adopted2S/Metal oxide or Li2When the S/carbon composite material is used as the anode active material of the lithium-sulfur battery, the lithium-sulfur battery has poor cycle stability.
The invention provides a positive active material of a lithium-sulfur battery, which comprises lithium sulfide and a carbon material doped with sulfur element, wherein the lithium sulfide and the carbon material are connected in a sintering way.
Further, the lithium-sulfur battery positive active material further comprises a conductive substance, and the conductive substance, the lithium sulfide and the carbon material doped with elemental sulfur are connected in a sintering manner.
The invention also aims to provide a preparation method of the positive electrode active material of the lithium-sulfur battery, which comprises the following steps:
uniformly mixing lithium sulfide and a sulfur-containing organic substance, or uniformly mixing sulfide, a sulfur-containing organic substance and a conductive substance, and roasting to obtain a positive electrode active material of a lithium-sulfur battery; wherein the content of the first and second substances,
in the lithium-sulfur battery positive active material, lithium sulfide is connected with a carbon material doped with sulfur element in a sintering way; or
And sintering and connecting the lithium sulfide with the carbon material doped with the sulfur element and the conductive substance.
Further, dissolving lithium sulfide and a sulfur-containing organic substance in a solvent respectively, uniformly mixing, and then removing the solvent, or dissolving lithium sulfide, a sulfur-containing organic substance and a conductive substance in a solvent respectively, uniformly mixing, and then removing the solvent to obtain a precursor material;
and roasting the precursor material to obtain the lithium-sulfur battery positive electrode active material.
Further, the sulfur-containing organic matter is a polymer containing carbon and sulfur;
preferably, the polymer containing carbon and sulfur is a polymer containing carbon and sulfur in the main chain;
preferably, the polymer containing carbon and sulfur is selected from at least one of polythiophene, polysulfone or polythioether.
Further, the conductive substance is selected from at least one of carbon nanotubes, carbon fibers, graphene oxide, or conductive carbon black.
Further, roasting under the protection of inert gas;
preferably, during roasting, the temperature rise speed is 1-5 ℃/min, the temperature rises to 600-1000 ℃, and the temperature is kept for 0.5-3h, so as to obtain the lithium-sulfur battery positive electrode active material.
Further, the solvent is selected from at least one of N-methyl pyrrolidone, tetrahydrofuran, chloroform, toluene, xylene, dichlorobenzene or dimethyl sulfoxide.
The invention also aims to provide a lithium-sulfur positive electrode material, which comprises the lithium-sulfur battery positive electrode active material provided by the invention or the positive electrode active material obtained by the preparation method of the lithium-sulfur battery positive electrode active material provided by the invention.
The invention also aims to provide a lithium-sulfur battery, which comprises the positive electrode active material of the lithium-sulfur battery provided by the invention, the positive electrode active material obtained by the preparation method of the positive electrode active material of the lithium-sulfur battery provided by the invention or the positive electrode material of the lithium-sulfur battery provided by the invention.
According to the lithium-sulfur battery positive active material provided by the invention, the lithium sulfide and the carbon material doped with the sulfur element are compounded, so that the conductivity of the lithium sulfide can be obviously improved, meanwhile, the carbon material doped with the sulfur element can provide a binding site for polysulfide, and the binding force between the polysulfide and the positive active material is improved, so that the lithium-sulfur battery can keep higher specific capacity, and the cycle stability is obviously improved.
According to the preparation method of the lithium-sulfur battery positive active material, the lithium sulfide and the sulfur-containing organic matter are mixed and then roasted, so that the lithium-sulfur battery positive active material compounded by the lithium sulfide and the carbon material doped with the sulfur element is obtained, the process is simple, the operation is convenient, the preparation method is suitable for industrial production, the production cost is reduced, and the production efficiency is improved.
The positive electrode material of the lithium-sulfur battery provided by the invention adopts the positive electrode active material of the lithium-sulfur battery as the positive electrode active material, so that the conductivity of the positive electrode material is improved, the lithium-sulfur battery can keep higher specific capacity, and the cycling stability is obviously improved.
The lithium-sulfur battery provided by the invention adopts the positive electrode active material of the lithium-sulfur battery as the positive electrode active material, so that not only can higher specific capacity be kept, but also the cycling stability is obviously improved.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
According to one aspect of the present invention, the present invention provides a positive active material for a lithium-sulfur battery, comprising lithium sulfide and a carbon material doped with elemental sulfur, which are sintered and connected.
According to the lithium-sulfur battery positive active material provided by the invention, the lithium sulfide and the carbon material doped with the sulfur element are compounded, so that the conductivity of the lithium sulfide can be obviously improved, meanwhile, the carbon material doped with the sulfur element can provide a binding site for polysulfide, and the binding force between the polysulfide and the positive active material is improved, so that the lithium-sulfur battery can keep higher specific capacity, and the cycle stability is obviously improved.
In a preferred embodiment of the present invention, the positive electrode active material for a lithium-sulfur battery further includes a conductive material, and the conductive material, lithium sulfide, and the carbon material doped with elemental sulfur are sinter-bonded.
By adding the conductive substance into the positive active material of the lithium-sulfur battery, the lithium sulfide, the conductive substance and the carbon material doped with sulfur are mutually cooperated, and the conductive performance of the positive active material is obviously improved.
According to a second aspect of the present invention, there is provided a method for preparing a positive electrode material for a lithium-sulfur battery, comprising the steps of: uniformly mixing lithium sulfide, a polymer containing carbon and sulfur and an optional conductive substance, and roasting to obtain a positive electrode active material of the sulfur-lithium-sulfur battery; wherein the content of the first and second substances,
in the positive active material of the lithium-sulfur battery, lithium sulfide is connected with a carbon material doped with sulfur element and an optional conductive substance by sintering.
In the present invention, among others, lithium sulfide: polymer (b): the mass ratio of the conductive agent is 100: 10-100: 0.5-10; further preferably 100: 20-80: 3-7; further preferably: 100: 30-60: 4-6; still more preferably 100: 40-50: 5-6.
According to the preparation method of the lithium-sulfur battery positive active material, the lithium sulfide and the sulfur-containing organic matter are uniformly mixed, or the sulfide, the sulfur-containing organic matter and the conductive substance are uniformly mixed and then are roasted, so that the composite lithium-sulfur battery positive active material is obtained.
In a preferred embodiment of the present invention, in the method for preparing the positive electrode active material of the lithium-sulfur battery, lithium sulfide and a sulfur-containing organic substance are respectively dissolved in a solvent and uniformly mixed to remove the solvent, or lithium sulfide, a sulfur-containing organic substance and a conductive substance are respectively dissolved in a solvent and uniformly mixed to remove the solvent, so as to obtain a precursor material; and removing the solvent to obtain a precursor material, and roasting the precursor material to obtain the lithium-sulfur battery positive electrode active material.
Through dissolving lithium sulfide and sulfur-containing organic matter, or lithium sulfide, sulfur-containing organic matter and conductive substance in the solvent, and then removing the solvent, the substances can be mixed more uniformly, and the method is favorable for generating more stable lithium-sulfur battery positive active material in the roasting process.
In a preferred embodiment of the present invention, the sulfur-containing organic substance is a polymer containing carbon and sulfur.
By selecting the polymer containing carbon element and sulfur element as the sulfur-containing carbon source, the polymer can be mixed with lithium sulfide more uniformly.
In a further preferred embodiment of the present invention, the polymer containing carbon and sulfur is a polymer containing carbon and sulfur in the main chain.
By selecting the polymer containing the carbon element and the sulfur element on the main chain, the sulfur-doped carbon material with the sulfur element uniformly distributed in the carbon material can be formed in the roasting process.
In a further preferred embodiment of the invention, the polymer containing elemental carbon and elemental sulfur is selected from one or more of polythiophene, polysulfone or polythioether.
In a preferred embodiment of the present invention, the weight average molecular weight of the polymer containing carbon and sulfur is 103-106So as to ensure that the polymer can be completely dissolved in the solvent and achieve the effect of uniform dispersion.
In a preferred embodiment of the present invention, the conductive material is selected from one or more of carbon nanotubes, graphene, and graphene oxide or conductive carbon black.
The conductive substance, the carbon material doped with the sulfur element and the lithium sulfide are mutually cooperated in the generated positive active material by selecting the conductive substance, the sulfur-containing organic matter and the lithium sulfide to be mixed and then sintered, so that the conductive performance of the positive active material is obviously improved.
In the preferred embodiment of the present invention, the conductive material, the lithium sulfide and the sulfur-containing organic material are mixed and baked, so that the baked conductive material, the carbon material doped with sulfur and the lithium sulfide are tightly combined, thereby improving the conductivity and stability of the cathode active material.
In a preferred embodiment of the invention, the calcination is carried out under an inert gas blanket.
The roasting is carried out under the protection of inert gas, so that the influence of other impurity elements on the performance of the positive active material in the roasting process is avoided.
In this preferred embodiment of the present invention, the inert gas is selected from at least one of helium, nitrogen and argon, preferably argon.
In a preferred embodiment of the invention, during roasting, the temperature rise speed is 1-5 ℃/min, the temperature is raised to 600-1000 ℃, and the temperature is kept for 0.5-3h, so as to obtain the lithium-sulfur battery positive electrode active material.
In this preferred embodiment of the invention, the calcination is carried out at a typical but non-limiting ramp rate of, for example, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 or 5 ℃/min, a typical but non-limiting soak temperature of, for example, 600, 650, 700, 750, 800, 850, 900, 950 or 1000 ℃, and a typical but non-limiting soak time of, for example, 0.5, 0.8, 1, 1.5, 2, 2.5 or 3 hours.
By controlling the roasting speed to be 1-5 ℃/min, raising the temperature to 600-plus-one temperature of 1000 ℃ and keeping the temperature for 0.5-3h, the lithium sulfide, the carbon material doped with the sulfur element and the conductive substance are combined more uniformly and compactly, so that the performance stability of the prepared positive electrode active material of the lithium-sulfur battery is ensured.
In a further preferred embodiment of the present invention, the calcination effect is better when the temperature rise rate is 2 ℃/min, the heat preservation temperature is 800-.
In a preferred embodiment of the present invention, the solution for mixing the three raw materials is one or more selected from the group consisting of N-methylpyrrolidone, tetrahydrofuran, chloroform, toluene, xylene, dichlorobenzene, and dimethylsulfoxide.
The organic solvent is selected as the solvent of the raw material, so that the three raw materials are mixed more uniformly, and the lithium-sulfur battery positive active material with more stable performance can be prepared in the roasting process conveniently.
In a preferred embodiment of the invention, the solvent removal method is selected from one of rotary evaporation, thermal evaporation or freeze drying, preferably rotary evaporation.
When the solvent is removed by rotary evaporation, on one hand, the solvent can be recovered, and on the other hand, the lithium sulfide and the conductive substance can be uniformly dispersed; when freeze drying is selected, the uniformity of material mixing can be maintained.
According to a third aspect of the invention, the invention provides a lithium-sulfur battery positive electrode material, which comprises the lithium-sulfur battery active material provided by the invention or the positive electrode active material obtained by the preparation method provided by the invention.
In a preferred embodiment of the present invention, the positive electrode material for a lithium sulfur battery further includes a conductive agent and a binder.
In a preferred embodiment of the present invention, the conductive agent is selected from one or more of graphite, carbon black, acetylene black, graphene, carbon fiber, and carbon nanotube.
In a preferred embodiment of the present invention, the binder is selected from one or more of polyacrylic acid, polytetrafluoroethylene, polyvinylidene chloride, soluble polytetrafluoroethylene, styrene butadiene rubber, hydroxypropyl methylcellulose, carboxymethyl cellulose, polyvinyl alcohol, acrylonitrile copolymer, sodium alginate, chitosan and chitosan derivatives.
The positive electrode material of the lithium-sulfur battery provided by the invention adopts the positive electrode active material of the lithium-sulfur battery as the positive electrode active material, so that the conductivity of the positive electrode material is improved, the lithium-sulfur battery can keep higher specific capacity, and the cycling stability is obviously improved.
According to a fourth aspect of the invention, the invention provides a lithium-sulfur battery, which comprises the positive electrode active material provided by the invention, the positive electrode active material prepared by the preparation method of the positive electrode active material provided by the invention or the positive electrode active material provided by the invention.
The lithium-sulfur battery provided by the invention adopts the positive electrode active material of the lithium-sulfur battery as the positive electrode active material, so that not only can higher specific capacity be kept, but also the cycling stability is obviously improved.
The technical solution provided by the present invention is further described below with reference to examples and comparative examples.
Example 1
The embodiment provides a positive active material of a lithium-sulfur battery, which comprises sintering connected lithium sulfide and a carbon material doped with sulfur element, and is prepared according to the following steps:
(1) 1g of poly-3-hexylthiophene (weight-average molecular weight: 10)5g/mol) in 50ml of tetrahydrofuran solvent;
(2) weighing 5gLi2S, ultrasonically dispersing in 50ml of tetrahydrofuran solvent;
(3) mixing the solutions obtained in the step (1) and the step (2), and magnetically stirring for 30min at the speed of 800 r/min;
(4) removing the tetrahydrofuran solvent in the step (3) by rotary evaporation at 68 ℃ to obtain a solid;
(5) and (4) putting the solid obtained in the step (4) into a crucible, heating to 850 ℃ at a heating rate of 2 ℃/min under the protection of argon, and keeping the temperature for 1h to obtain the lithium-sulfur battery active material.
Example 2
The present example provides a positive active material for a lithium-sulfur battery, which is prepared according to the following steps:
(1) 1g of poly-3-hexylthiophene (weight-average molecular weight: 10)5g/mol) in 50ml of tetrahydrofuran solvent;
(2) 0.05g of carbon nanotubes and 5gLi g of carbon nanotubes were weighed out separately2S, ultrasonically dispersing in 50ml of tetrahydrofuran solvent;
(3) mixing the solutions obtained in the step (1) and the step (2), and magnetically stirring for 30min at the speed of 800 r/min;
(4) removing the tetrahydrofuran solvent in the step (3) by rotary evaporation at 68 ℃ to obtain a solid;
(5) and (4) putting the solid obtained in the step (4) into a crucible, heating to 850 ℃ at a heating rate of 2 ℃/min under the protection of argon, and keeping the temperature for 1h to obtain the lithium-sulfur battery active material.
Example 3
The present example provides a positive active material for a lithium-sulfur battery, which is prepared according to the following steps:
(1) 1g of polyphenylene sulfide (weight average molecular weight: 10) was weighed5g/mol)，Dissolving in 50ml NMP (N-methylpyrrolidone) solvent;
(2) 0.05g of graphene and 5gLi g of graphene are weighed respectively2S, ultrasonically dispersing in 50ml of tetrahydrofuran solvent;
(3) mixing the solutions obtained in the step (1) and the step (2), and magnetically stirring for 30min at the speed of 800 r/min;
(4) removing the NMP solvent in the step (3) by rotary evaporation at 203 ℃ to obtain a solid;
(5) and (4) putting the solid obtained in the step (4) into a crucible, heating to 850 ℃ at a heating rate of 2 ℃/min under the protection of argon, and keeping the temperature for 1h to obtain the lithium-sulfur battery active material.
Example 4
The present example provides a positive active material for a lithium-sulfur battery, which is prepared according to the following steps:
(1) 1g of polyethersulfone (weight average molecular weight 10) was weighed5g/mol) in 50ml of tetrahydrofuran solvent;
(2) 0.05g of graphene oxide and 5gLi g of graphene oxide were weighed out separately2S, ultrasonically dispersing in 50ml of tetrahydrofuran solvent;
(3) mixing the solutions obtained in the step (1) and the step (2), and magnetically stirring for 30min at the speed of 800 r/min;
(4) removing the tetrahydrofuran solvent in the step (3) by rotary evaporation at 68 ℃ to obtain a solid;
(5) and (4) putting the solid obtained in the step (4) into a crucible, heating to 850 ℃ at a heating rate of 2 ℃/min under the protection of argon, and keeping the temperature for 1h to obtain the lithium-sulfur battery active material.
Comparative example 1
This comparative example provides a positive active material for a lithium-sulfur battery, which was prepared in a method different from that of example 1 in that polyacrylonitrile was used instead of poly-3-hexylthiophene in step (1).
Comparative example 2
This comparative example provides a positive active material for a lithium-sulfur battery, which was prepared in a method different from that of example 2 in that polyacrylonitrile was used instead of poly-3-hexylthiophene in step (1).
Comparative example 3
This comparative example provides a positive active material for a lithium-sulfur battery, which was prepared by a method different from that of example 2 in that, in step (1), a phenol resin was used instead of poly-3-hexylthiophene.
Comparative example 4
This comparative example provides a positive active material for a lithium-sulfur battery, which was prepared by a method different from that of example 2 in that epoxy resin was used instead of poly-3-hexylthiophene in step (1).
Comparative example 5
This comparative example provides a positive active material for a lithium-sulfur battery, which was prepared in a method different from that of example 2 in that step (1) and step (3) were not performed, i.e., no sulfur-containing organic material was added to the raw material.
Examples 5 to 8
Examples 5 to 8 respectively provide a positive electrode material for a lithium sulfur battery, which comprises the positive electrode active material for a lithium sulfur battery, conductive carbon black and a binder (polyacrylic acid) provided in examples 1 to 4, in a mass ratio of 8: 1: 1.
comparative examples 6 to 10
Comparative examples 6 to 10 respectively provide a positive electrode material for lithium sulfur batteries, respectively comprising the positive electrode active material for lithium sulfur batteries, provided in comparative examples 1 to 5, conductive carbon black and a binder (polyacrylic acid), in a mass ratio of 8: 1: 1.
examples 9 to 12
Examples 9 to 12 each provide a lithium sulfur battery fabricated by assembling a positive electrode sheet, a lithium foil for a counter electrode, a separator and an electrolyte, wherein the positive electrode sheets are prepared by coating the positive electrode materials provided in examples 5 to 8 on aluminum foils, respectively.
Comparative examples 11 to 15
Comparative examples 11 to 15 respectively provide lithium sulfur batteries each assembled from a positive electrode sheet, a lithium foil for a counter electrode, a separator and an electrolyte, wherein the positive electrode sheets were each prepared by coating the positive electrode material provided in comparative examples 6 to 10 on an aluminum foil.
Test example 1
The lithium sulfur batteries provided in examples 9 to 12 and comparative examples 10 to 15 were subjected to specific capacity and 80% cycle life tests, respectively, and the results are shown in table 1.
TABLE 1 lithium-sulfur battery Performance data sheet
| Gram capacity (mAh/g) | 80% cycle life (week) | |
| Example 9 | 950 | 350 |
| Example 10 | 1073 | 400 |
| Example 11 | 1027 | 380 |
| Example 12 | 995 | 380 |
| Comparative example 11 | 868 | 150 |
| Comparative example 12 | 968 | 200 |
| Comparative example 13 | 890 | 180 |
| Comparative example 14 | 833 | 150 |
| Comparative example 15 | 910 | 30 |
As can be seen from table 1, the gram capacity and cycle life of the lithium sulfur battery provided in example 9 are significantly higher than those of comparative example 11, which indicates that the gram capacity and cycle stability of the lithium sulfur battery provided in example 9 are significantly higher than those of the undoped lithium sulfide cathode active material by using the cathode active material in which lithium sulfide is composited with the carbon material doped with elemental sulfur.
As can be seen from the comparison between examples 10 to 12 and example 9, the gram capacity and the cycling stability of the lithium-sulfur battery are significantly improved by using the positive electrode active material in which lithium sulfide is compounded with the conductive material and the carbon material doped with sulfur, which is significantly higher than those of the lithium-sulfur battery made of the positive electrode material in which lithium sulfide is compounded with the carbon material doped with sulfur.
It can be seen from the comparison of examples 10 to 12 with comparative examples 12 to 15 that the use of the positive electrode active material in which lithium sulfide is compounded with a conductive material and a carbon material doped with sulfur element not only enables a higher specific capacity to be maintained but also significantly improves the cycle stability.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (8)
1. A preparation method of a positive electrode active material of a lithium-sulfur battery is characterized by comprising the following steps:
uniformly mixing lithium sulfide and a sulfur-containing organic substance, or uniformly mixing sulfide, a sulfur-containing organic substance and a conductive substance, and roasting to obtain a positive electrode active material of a lithium-sulfur battery; wherein the content of the first and second substances,
in the lithium-sulfur battery positive active material, lithium sulfide is connected with a carbon material doped with sulfur element in a sintering way; or the like, or, alternatively,
sintering and connecting lithium sulfide with a carbon material doped with sulfur and a conductive substance;
in the preparation method, firstly, respectively dissolving lithium sulfide and a sulfur-containing organic substance in a solvent, uniformly mixing, and then removing the solvent, or respectively dissolving lithium sulfide, a sulfur-containing organic substance and a conductive substance in a solvent, uniformly mixing, and then removing the solvent, so as to obtain a precursor material;
roasting the precursor material to obtain the lithium-sulfur battery positive active material;
the sulfur-containing organic matter is a polymer containing carbon and sulfur;
the polymer containing carbon and sulfur is a polymer containing carbon and sulfur on the main chain.
2. The method according to claim 1, wherein the polymer containing elemental carbon and elemental sulfur is at least one selected from the group consisting of polythiophene, polysulfone, and polythioether.
3. The production method according to claim 1, wherein the conductive substance is at least one selected from the group consisting of carbon nanotubes, carbon fibers, graphene oxide, and conductive carbon black.
4. The method according to claim 1, wherein the firing is performed under an inert gas atmosphere.
5. The preparation method as claimed in claim 4, wherein the temperature is raised to 1000 ℃ at a rate of 1-5 ℃/min during the calcination, and the temperature is maintained for 0.5-3h to obtain the positive active material of the lithium-sulfur battery.
6. The method according to claim 1, wherein the solvent is at least one selected from the group consisting of N-methylpyrrolidone, tetrahydrofuran, chloroform, toluene, xylene, dichlorobenzene, and dimethylsulfoxide.
7. A positive electrode material for a lithium-sulfur battery, comprising the positive electrode active material obtained by the production method according to any one of claims 1 to 6.
8. A lithium-sulfur battery comprising the positive electrode active material obtained by the production method according to any one of claims 1 to 6, or comprising the positive electrode material for a lithium-sulfur battery according to claim 7.
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Citations (5)
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| CN105977488A (en) * | 2015-03-13 | 2016-09-28 | 现代自动车株式会社 | Method for manufacturing positive active material for all-solid lithium-sulfur battery |
| CN106159221A (en) * | 2015-04-27 | 2016-11-23 | 中国人民解放军63971部队 | A kind of nano-sized carbon sulfur composite for lithium-sulfur cell |
| CN106299307A (en) * | 2016-09-30 | 2017-01-04 | 上海空间电源研究所 | A kind of lithium-sulfur cell high-performance positive electrode and preparation method thereof |
| CN107026260A (en) * | 2016-02-02 | 2017-08-08 | 中国科学院苏州纳米技术与纳米仿生研究所 | A kind of lithium sulfide/carbon nano-composite material, its preparation method and application |
| JP2017216054A (en) * | 2016-05-30 | 2017-12-07 | トヨタ自動車株式会社 | Method for manufacturing lithium sulfur battery |
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Patent Citations (5)
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| CN105977488A (en) * | 2015-03-13 | 2016-09-28 | 现代自动车株式会社 | Method for manufacturing positive active material for all-solid lithium-sulfur battery |
| CN106159221A (en) * | 2015-04-27 | 2016-11-23 | 中国人民解放军63971部队 | A kind of nano-sized carbon sulfur composite for lithium-sulfur cell |
| CN107026260A (en) * | 2016-02-02 | 2017-08-08 | 中国科学院苏州纳米技术与纳米仿生研究所 | A kind of lithium sulfide/carbon nano-composite material, its preparation method and application |
| JP2017216054A (en) * | 2016-05-30 | 2017-12-07 | トヨタ自動車株式会社 | Method for manufacturing lithium sulfur battery |
| CN106299307A (en) * | 2016-09-30 | 2017-01-04 | 上海空间电源研究所 | A kind of lithium-sulfur cell high-performance positive electrode and preparation method thereof |
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