CN110797532B - Composite positive electrode material of lithium-sulfur battery and preparation method thereof - Google Patents
Composite positive electrode material of lithium-sulfur battery and preparation method thereof Download PDFInfo
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- 239000007774 positive electrode material Substances 0.000 title claims abstract description 52
- 239000002131 composite material Substances 0.000 title claims abstract description 43
- JDZCKJOXGCMJGS-UHFFFAOYSA-N [Li].[S] Chemical compound [Li].[S] JDZCKJOXGCMJGS-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 52
- 229910021389 graphene Inorganic materials 0.000 claims abstract description 52
- 229920000767 polyaniline Polymers 0.000 claims abstract description 24
- 238000000034 method Methods 0.000 claims abstract description 9
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims description 46
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 claims description 42
- 239000010410 layer Substances 0.000 claims description 29
- 239000002210 silicon-based material Substances 0.000 claims description 28
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims description 23
- 229910004283 SiO 4 Inorganic materials 0.000 claims description 19
- 238000001027 hydrothermal synthesis Methods 0.000 claims description 16
- 238000001354 calcination Methods 0.000 claims description 14
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 14
- 238000002156 mixing Methods 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000006116 polymerization reaction Methods 0.000 claims description 10
- YUKQRDCYNOVPGJ-UHFFFAOYSA-N thioacetamide Chemical compound CC(N)=S YUKQRDCYNOVPGJ-UHFFFAOYSA-N 0.000 claims description 8
- DLFVBJFMPXGRIB-UHFFFAOYSA-N thioacetamide Natural products CC(N)=O DLFVBJFMPXGRIB-UHFFFAOYSA-N 0.000 claims description 8
- 238000011068 loading method Methods 0.000 claims description 7
- 239000011247 coating layer Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 abstract description 14
- 239000010405 anode material Substances 0.000 abstract description 13
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 7
- 229910052717 sulfur Inorganic materials 0.000 abstract description 7
- 239000011593 sulfur Substances 0.000 abstract description 7
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 239000013543 active substance Substances 0.000 abstract description 4
- 150000003377 silicon compounds Chemical class 0.000 abstract description 3
- 239000000126 substance Substances 0.000 abstract description 3
- 230000005540 biological transmission Effects 0.000 abstract description 2
- 230000001351 cycling effect Effects 0.000 abstract description 2
- 238000003487 electrochemical reaction Methods 0.000 abstract description 2
- 230000001681 protective effect Effects 0.000 abstract description 2
- 230000009286 beneficial effect Effects 0.000 abstract 2
- 239000000243 solution Substances 0.000 description 24
- 239000000047 product Substances 0.000 description 14
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 11
- 239000007864 aqueous solution Substances 0.000 description 11
- 238000005303 weighing Methods 0.000 description 9
- 239000008367 deionised water Substances 0.000 description 8
- 229910021641 deionized water Inorganic materials 0.000 description 8
- 229910010707 LiFePO 4 Inorganic materials 0.000 description 7
- 238000001291 vacuum drying Methods 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 239000000725 suspension Substances 0.000 description 6
- 229910010710 LiFePO Inorganic materials 0.000 description 5
- 238000004140 cleaning Methods 0.000 description 5
- 239000005457 ice water Substances 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000001132 ultrasonic dispersion Methods 0.000 description 4
- 229910052593 corundum Inorganic materials 0.000 description 3
- 239000010431 corundum Substances 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 238000003760 magnetic stirring Methods 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 238000007873 sieving Methods 0.000 description 3
- 238000002791 soaking Methods 0.000 description 3
- FFRBMBIXVSCUFS-UHFFFAOYSA-N 2,4-dinitro-1-naphthol Chemical compound C1=CC=C2C(O)=C([N+]([O-])=O)C=C([N+]([O-])=O)C2=C1 FFRBMBIXVSCUFS-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 239000011258 core-shell material Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 230000003446 memory effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002954 polymerization reaction product Substances 0.000 description 1
- 229920001021 polysulfide Polymers 0.000 description 1
- 239000005077 polysulfide Substances 0.000 description 1
- 150000008117 polysulfides Polymers 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
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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
- 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
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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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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- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
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- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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Abstract
The invention belongs to the technical field of lithium-sulfur batteries, and particularly relates to a lithium-sulfur battery composite positive electrode material and a preparation method thereof. In the invention, the polyaniline layer has a protective effect on the composite anode material, has higher conductivity and more complete structure, and is beneficial to realizing charge and discharge under high current density; the PANI conductive layer does not participate in electrochemical reaction, so that the conductive performance of the PANI conductive layer is improved, the PANI conductive layer can be well adapted to the charge and discharge process under high current density, meanwhile, the PANI layer reduces the loss of active substances in the charge and discharge process, and the structural integrity is maintained; PANI layer contains silicon compound and VS 4 Better adapt to Li + The volume change caused by embedding and de-embedding improves the charge-discharge cycling stability of the composite anode material; the graphene material has a large specific surface area, so that the graphene material has a large contact area with a sulfur simple substance, is beneficial to improving the electron transmission rate and the reaction area, and contains silicon compound and VS 4 The specific capacity of the composite positive electrode material can be further improved.
Description
Technical Field
The invention belongs to the technical field of lithium-sulfur batteries, and particularly relates to a lithium-sulfur battery composite positive electrode material and a preparation method thereof.
Background
The lithium-sulfur battery has the advantages of large specific energy, high working voltage, long cycle life, low self-discharge rate, no memory effect, environmental friendliness and the like, and is widely applied to the field of portable electronic equipment. The material used as the positive electrode material is also continuously expanded, and is used as an important component in the lithium sulfur battery, so that the large-scale popularization and application of the lithium sulfur battery are restricted. When the lithium-sulfur battery uses sulfur as a positive electrode material, the problems of poor electrochemical performance, low utilization rate and the like of sulfur in an electrode are caused by low ionic conductivity and electronic conductivity of the sulfur, and lithium polysulfide generated in the charging and discharging process can be irreversibly dissolved in electrolyte, and dispersed sulfur particles can be agglomerated. In addition, the conductive structure of the electrode may be changed during charge and discharge, and these factors cause degradation of the cyclic charge and discharge performance and decrease of specific capacity of the battery.
Disclosure of Invention
In view of the above, the present invention aims to provide a lithium-sulfur battery composite positive electrode material and a preparation method thereof. The lithium-sulfur battery composite anode material provided by the invention has good cyclic charge and discharge performance and high specific capacity.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a lithium-sulfur battery composite anode material,comprises a lithium iron phosphate layer, a graphene wrapping layer and a polyaniline layer which are sequentially stacked, wherein the graphene wrapping layer comprises a silicon-containing compound and VS 4 The silicon-containing compound and VS 4 Loaded on graphene.
Preferably, the mass content of the graphene coating layer is 15-20%.
Preferably, the mass content of the polyaniline layer is 5-10%.
Preferably, the silicon-containing compound comprises Li 2 SiO 3 、Li 4 SiO 4 And one or more of silica.
Preferably, the silicon-containing compound and VS 4 The loading amount on the graphene is 30-40 wt%.
Preferably, the silicon-containing compound and VS 4 The mass ratio of (2) is 1:1-5.
The invention also provides a preparation method of the lithium-sulfur battery composite anode material, which comprises the following steps:
providing a lithium iron phosphate positive electrode material;
graphene oxide, water and Na 3 VO 4 Mixing with thioacetamide and then carrying out hydrothermal reaction to obtain a hydrothermal product;
mixing the lithium iron phosphate positive electrode material, the silicon-containing compound solution and the hydrothermal product, and calcining to obtain a graphene-coated positive electrode material;
and immersing the graphene-coated positive electrode material in aniline for polymerization reaction to obtain the lithium-sulfur battery composite positive electrode material.
Preferably, the temperature of the hydrothermal reaction is 160-180 ℃, and the time of the hydrothermal reaction is 20-24 hours.
Preferably, the calcination temperature is 400-600 ℃ and the time is 1-2 h.
Preferably, the aniline is polymerized in the presence of ammonium persulfate in a molar ratio of 1:1.
The invention provides a lithium-sulfur battery composite positive electrode material, which comprises sequentially laminated phosphorusLithium iron oxide layer, graphene coating layer and polyaniline layer, wherein the graphene coating layer comprises silicon-containing compound and VS 4 The silicon-containing compound and VS 4 Loaded on graphene. In the invention, the core-shell structure material taking PANI (polyaniline) as the shell has the advantages of simple structure, low cost, stable circulation and high circulation capacity, and the polyaniline layer has a protective effect on the composite anode material, so that compared with the composite material directly exposed to the electrolyte environment, the composite anode material coated by the polyaniline layer has higher conductivity and more complete structure, is favorable for realizing charge and discharge under high current density, and has great potential in development and application of the lithium-sulfur battery; the PANI conductive layer does not participate in electrochemical reaction, and is coated on the surface of the silicon-containing compound to improve the conductivity of the silicon-containing compound, so that the silicon-containing compound can be well adapted to the charge-discharge process under high current density, and meanwhile, the PANI layer reduces the loss of active substances of the silicon-containing compound in the charge-discharge process, such as the falling and dissolution of the active substances in the charge-discharge process, so that the structural integrity is maintained; PANI layer contains silicon compound and VS 4 Better adapt to Li + The volume change caused by embedding and de-embedding reduces the loss of active substances on a current collector, thereby obviously improving the charge-discharge cycling stability of the anode material; silicon-containing compound and VS 4 The graphene material is loaded on graphene, the specific surface area of the graphene material is large, so that the graphene material has a larger contact area with a sulfur simple substance, the electron transmission rate and the reaction area are improved, the conductivity and the cycle performance of the sulfur simple substance positive electrode material are improved, and meanwhile, the silicon-containing compound and the VS are improved 4 The specific capacity of the composite positive electrode material can be further improved. The data of the embodiment show that the lithium-sulfur battery composite positive electrode material provided by the invention has the initial discharge specific capacity of 1782-1947 mAh/g under the charge-discharge current density of 100mA/g, and the discharge specific capacity is kept at 90-94% after 50 times of circulation.
Detailed Description
The invention provides a lithium-sulfur battery composite positive electrode material, which comprises a lithium iron phosphate layer, a graphene wrapping layer and a polyaniline layer which are sequentially stacked, wherein the graphene wrapping layer comprises a silicon-containing compound and VS 4 The silicon-containing compound and VS 4 Load(s)On graphene.
In the invention, the mass content of the graphene coating layer is preferably 15-20%.
In the present invention, the mass content of the polyaniline layer is preferably 5 to 10%.
In the present invention, the silicon-containing compound preferably includes Li 2 SiO 3 、Li 4 SiO 4 And one or more of silica.
In the present invention, the silicon-containing compound and VS 4 The loading on the graphene is preferably 30 to 40wt%.
In the present invention, the silicon-containing compound and VS 4 The mass ratio of (2) is preferably 1:1-5.
The invention also provides a preparation method of the lithium-sulfur battery composite anode material, which comprises the following steps:
providing a lithium iron phosphate positive electrode material;
graphene oxide, water and Na 3 VO 4 Mixing with thioacetamide and then carrying out hydrothermal reaction to obtain a hydrothermal product;
mixing the lithium iron phosphate positive electrode material, the silicon-containing compound solution and the hydrothermal product, and calcining to obtain a graphene-coated positive electrode material;
and immersing the graphene-coated positive electrode material in aniline for polymerization reaction to obtain the lithium-sulfur battery composite positive electrode material.
The invention provides a lithium iron phosphate positive electrode material. In the present invention, the lithium iron phosphate positive electrode material is preferably spherical. In the present invention, the lithium iron phosphate positive electrode material is preferably subjected to pretreatment before use, preferably comprising sieving and calcination, and the specific manner of the sieving and calcination is not particularly limited, and in the embodiment of the present invention, it is preferable that the sieving gives material particles having a particle size of 1 to 10 μm and then the calcination is performed at 400 to 600 ℃.
The invention oxidizes graphene, water and Na 3 VO 4 And mixing with thioacetamide, and performing hydrothermal reaction to obtain a hydrothermal product.
In the present invention, the temperature of the hydrothermal reaction is preferably 160 to 180 ℃, and the time of the hydrothermal reaction is preferably 20 to 24 hours.
In the present invention, the Na 3 VO 4 And thioacetamide are preferably present in a molar ratio of from 1:5 to 1:6.
In the invention, the graphene oxide and Na 3 VO 4 The mass ratio of (2) is preferably 1:27 to 1:28, more preferably 1:27.5 to 1:28.
After the hydrothermal reaction is finished, the hydrothermal reaction product is preferably obtained by alternately cleaning the hydrothermal reaction product with deionized water and ethanol, and then vacuum drying is carried out to obtain the hydrothermal product. In the present invention, the number of times of the alternate cleaning is independently preferably 4 to 6 times. In the present invention, the temperature of the vacuum drying is preferably 60 to 80 ℃, more preferably 65 to 85 ℃, and the time of the vacuum drying is preferably 10 to 12 hours.
After the lithium iron phosphate positive electrode material and the hydrothermal product are obtained, the lithium iron phosphate positive electrode material, the silicon-containing compound solution and the hydrothermal product are mixed and calcined, so that the graphene-coated positive electrode material is obtained.
In the present invention, the calcination temperature is preferably 400 to 600 ℃, the time is preferably 1 to 2 hours, and the temperature rising rate to the calcination temperature is preferably 5 to 10 ℃/min. In the present invention, the calcination is preferably performed in air. In the present invention, the silicon-containing compound solution preferably includes Li 2 SiO 3 Aqueous solution, li 4 SiO 4 One or more of an aqueous solution and an absolute ethanol solution of ethyl orthosilicate. In the present invention, the concentration of the silicon-containing compound solution is preferably 0.01 to 1mmol/L.
In the present invention, the mixing is preferably ultrasonic dispersion for 0.5 to 2 hours.
After the graphene-coated positive electrode material is obtained, the graphene-coated positive electrode material is soaked in aniline for polymerization reaction, and the lithium-sulfur battery composite positive electrode material is obtained.
In the present invention, the aniline is preferably polymerized in the presence of ammonium persulfate, and the molar ratio of aniline to ammonium persulfate is preferably 1:1.
In the present invention, the ammonium persulfate is preferably added in the form of an HCl solution of ammonium persulfate, and the HCl solution of ammonium persulfate is preferably added dropwise, and the dropwise addition is performed in an ice-water bath under stirring. In the present invention, the dropwise addition is preferably a dropwise addition.
In the present invention, the polymerization is preferably performed in an ice-water bath, and the polymerization time is preferably 8 to 10 hours.
After the polymerization reaction is finished, the invention preferably uses deionized water and ethanol to alternately clean the obtained polymerization reaction product, and then carries out vacuum drying to obtain the lithium-sulfur battery composite anode material.
In order to further illustrate the present invention, the lithium sulfur battery composite cathode material and the preparation method thereof provided by the present invention are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
(1) Fe is added to 3 (PO 4 ) 2 Powder and Li 2 CO 3 Fully and uniformly mixing according to the stoichiometric ratio, calcining for 10 hours at 400 ℃ in nitrogen atmosphere to obtain LiFePO 4 。
(2) Weighing graphene oxide powder in 150mL of deionized water, ultrasonically dispersing until the solution is golden yellow, and sequentially adding Na with a metering ratio of 1:5 3 VO 4 (2.0125 g) and thioacetamide, and stirred for 1h. The solution is transferred into a hydrothermal reaction kettle and reacted for 24 hours at 160 ℃. After the reaction is finished, alternately cleaning the mixture for 4 to 6 times by deionized water and ethanol, and vacuum drying the mixture at 60 ℃ for 12 hours to obtain a hydrothermal product, wherein VS 4 The loading on graphene was 32wt%;
according to Li 4 SiO 4 The content was 8wt% based on the mass of graphene, li was weighed 4 SiO 4 Aqueous solution, 0.01mmol/L of Li is obtained 4 SiO 4 An aqueous solution. LiFePO is prepared 4 Hydrothermal products and Li 4 SiO 4 The aqueous solution is subjected to ultrasonic dispersion for 1h to obtain a suspension with uniform dispersion, the suspension is moved to a magnetic heating stirrer, the magnetic stirring is continued and the heating is carried out at 30 ℃ until the materials are dried, the dried materials are moved into a corundum boat, the temperature is programmed to 600 ℃ in a muffle furnace, and the temperature is kept for 4h to obtain a layer of graphene-coated LiFePO 4 The mass of the graphene accounts for 20% of the total mass of the composite positive electrode material;
(3) Weighing aniline according to the mass content of the polyaniline layer accounting for 10 percent of the total mass of the composite positive electrode material, weighing ammonium persulfate according to the molar ratio of the aniline to the ammonium persulfate of 1:1, mixing the ammonium persulfate with an HCl solution to obtain an HCl solution of the ammonium persulfate, dripping the HCl solution of the ammonium persulfate into the aniline under the conditions of ice-water bath and stirring, and adding Li 4 SiO 4 Coated LiFePO 4 Soaking in aniline for polymerization reaction for 8 hours to obtain the lithium-sulfur battery composite anode material.
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the embodiment is tested, and the result is as follows: the specific discharge capacity for the first time is 1947mAh/g under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 94% after 50 cycles.
Comparative example 1
The same as in example 1, except that the lithium sulfur battery composite positive electrode material does not contain a polyaniline layer.
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the comparative example is tested, and the result is as follows: the specific discharge capacity for the first time is 1647mAh/g under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 70% after 50 cycles.
Example 2
(1) Fe is added to 3 (PO 4 ) 2 Powder and Li 2 CO 3 Fully and uniformly mixing according to the stoichiometric ratio, calcining for 10 hours at 400 ℃ in nitrogen atmosphere to obtain LiFePO 4 。
(2) Weighing graphene oxide powder in 150mL of deionized water, and dispersing the graphene oxide powder into a solution by ultrasonicGolden yellow, then sequentially adding Na with the metering ratio of 1:5 3 VO 4 (2.0125 g) and thioacetamide, and stirred for 1h. The solution is transferred into a hydrothermal reaction kettle and reacted for 24 hours at 160 ℃. After the reaction is finished, alternately cleaning the mixture for 4 to 6 times by deionized water and ethanol, and vacuum drying the mixture at 60 ℃ for 12 hours to obtain a hydrothermal product, wherein VS 4 The loading on graphene was 15wt%;
according to Li 4 SiO 4 The content accounts for 15wt% of the mass of the graphene, and Li is weighed 4 SiO 4 Aqueous solution, 0.01mmol/L of Li is obtained 4 SiO 4 An aqueous solution. LiFePO is prepared 4 Hydrothermal products and Li 4 SiO 4 The aqueous solution is subjected to ultrasonic dispersion for 1h to obtain a suspension with uniform dispersion, the suspension is moved to a magnetic heating stirrer, the magnetic stirring is continued and the heating is carried out at 30 ℃ until the materials are dried, the dried materials are moved into a corundum boat, the temperature is programmed to 600 ℃ in a muffle furnace, and the temperature is kept for 4h to obtain a layer of graphene-coated LiFePO 4 The mass of the graphene accounts for 15% of the total mass of the composite positive electrode material;
(3) Weighing aniline according to the mass content of the polyaniline layer accounting for 5wt% of the total mass of the composite positive electrode material, weighing ammonium persulfate according to the molar ratio of the aniline to the ammonium persulfate of 1:1, mixing the ammonium persulfate with an HCl solution to obtain an HCl solution of ammonium persulfate, dripping the HCl solution of ammonium persulfate into the aniline under the conditions of ice-water bath and stirring, and coating LiFePO with graphene 4 Soaking in aniline for polymerization reaction for 8 hours to obtain the lithium-sulfur battery composite anode material.
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the embodiment is tested, and the result is as follows: the specific discharge capacity for the first time is 1782mAh/g under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 90% after 50 cycles.
Comparative example 2
The same as in example 2, except that VS was not added 4 。
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the comparative example is tested, and the result is as follows: the specific discharge capacity for the first time is 1467mAh/g under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 78% after 50 cycles.
Example 3
(1) Fe is added to 3 (PO 4 ) 2 powder and Li 2 CO 3 Fully and uniformly mixing according to the stoichiometric ratio, calcining for 10 hours at 400 ℃ in nitrogen atmosphere to obtain LiFePO 4 。
(2) Weighing graphene oxide powder in 150mL of deionized water, ultrasonically dispersing until the solution is golden yellow, and sequentially adding Na with a metering ratio of 1:5 3 VO 4 (2.0125 g) and thioacetamide, and stirred for 1h. The solution is transferred into a hydrothermal reaction kettle and reacted for 24 hours at 160 ℃. After the reaction is finished, alternately cleaning the mixture for 4 to 6 times by deionized water and ethanol, and vacuum drying the mixture at 60 ℃ for 12 hours to obtain a hydrothermal product, wherein VS 4 The loading on graphene was 30wt%;
according to Li 4 SiO 4 The content was 6wt% based on the mass of graphene, li was weighed 4 SiO 4 Aqueous solution, 0.01mmol/L of Li is obtained 4 SiO 4 An aqueous solution. LiFePO is prepared 4 Hydrothermal products and Li 4 SiO 4 The aqueous solution is subjected to ultrasonic dispersion for 1h to obtain a suspension with uniform dispersion, the suspension is moved to a magnetic heating stirrer, the magnetic stirring is continued and the heating is carried out at 30 ℃ until the materials are dried, the dried materials are moved into a corundum boat, the temperature is programmed to 600 ℃ in a muffle furnace, and the temperature is kept for 4h to obtain a layer of graphene-coated LiFePO 4 The mass of the graphene accounts for 18% of the total mass of the composite positive electrode material;
(3) Weighing aniline according to the mass content of the polyaniline layer accounting for 6wt% of the total mass of the composite positive electrode material, weighing ammonium persulfate according to the molar ratio of the aniline to the ammonium persulfate of 1:1, mixing the ammonium persulfate with an HCl solution to obtain an HCl solution of ammonium persulfate, dripping the HCl solution of ammonium persulfate into the aniline under the conditions of ice-water bath and stirring, and coating LiFePO with graphene 4 Soaking in aniline for polymerization reaction for 8 hours to obtain the lithium-sulfur battery composite anode material.
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the embodiment is tested, and the result is as follows: the specific discharge capacity for the first time is 1872mAh/g under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 92% after 50 cycles.
Comparative example 3
The same as in example 3, except that the silicon-containing compound was not added.
The electrochemical performance of the lithium-sulfur battery composite positive electrode material prepared in the comparative example is tested, and the result is as follows: the specific discharge capacity is 1501mAh/g for the first time under the charge-discharge current density of 100mA/g, and the specific discharge capacity is kept at 76% after 50 cycles.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (5)
1. The lithium-sulfur battery composite positive electrode material is characterized by comprising a lithium iron phosphate layer, a graphene wrapping layer and a polyaniline layer which are sequentially stacked, wherein the graphene wrapping layer comprises a silicon-containing compound and VS 4 The silicon-containing compound and VS 4 Loading on graphene;
the mass content of the graphene coating layer is 20%;
the mass content of the polyaniline layer is 10%;
the silicon-containing compound is Li 4 SiO 4 The Li is 4 SiO 4 And VS (VS) 4 The mass ratio of the Li is 1:4 4 SiO 4 And VS (VS) 4 The loading on graphene was 40wt%.
2. The method for preparing the lithium-sulfur battery composite positive electrode material as claimed in claim 1, which is characterized by comprising the following steps:
providing a lithium iron phosphate positive electrode material;
graphene oxide, water and Na 3 VO 4 Mixing with thioacetamide and then carrying out hydrothermal reaction to obtain a hydrothermal product;
mixing the lithium iron phosphate positive electrode material, the silicon-containing compound solution and the hydrothermal product, and calcining to obtain a graphene-coated positive electrode material;
and immersing the graphene-coated positive electrode material in aniline for polymerization reaction to obtain the lithium-sulfur battery composite positive electrode material.
3. The preparation method according to claim 2, wherein the temperature of the hydrothermal reaction is 160-180 ℃, and the time of the hydrothermal reaction is 20-24 hours.
4. The method according to claim 2, wherein the calcination is carried out at a temperature of 400 to 600 ℃ for a time of 1 to 2 hours.
5. The method of claim 2, wherein the aniline is polymerized in the presence of ammonium persulfate, and wherein the molar ratio of aniline to ammonium persulfate is 1:1.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1162677A2 (en) * | 1996-05-22 | 2001-12-12 | Moltech Corporation | Electrochemical cells comprising composite cathodes, and processes for fabricating same |
| CN105514378A (en) * | 2015-12-22 | 2016-04-20 | 湘潭大学 | Lithium-sulfur battery positive-pole composite material with imitated cellular structure and preparation method thereof |
| CN106876699A (en) * | 2015-12-13 | 2017-06-20 | 中国科学院大连化学物理研究所 | A kind of combination electrode and its preparation and application |
| CN108987725A (en) * | 2018-08-21 | 2018-12-11 | 南开大学 | A kind of anode composite material of lithium sulfur battery and preparation method thereof |
| CN109585828A (en) * | 2018-11-29 | 2019-04-05 | 济南大学 | RGO/VS is prepared in situ in one-step method4/ S compound is as lithium sulfur battery anode material |
| CN109755553A (en) * | 2019-03-20 | 2019-05-14 | 北京航空航天大学 | A kind of magnesium lithium Dual-ion cell composite positive pole and its preparation method and application, battery system |
-
2019
- 2019-11-12 CN CN201911098999.7A patent/CN110797532B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1162677A2 (en) * | 1996-05-22 | 2001-12-12 | Moltech Corporation | Electrochemical cells comprising composite cathodes, and processes for fabricating same |
| CN106876699A (en) * | 2015-12-13 | 2017-06-20 | 中国科学院大连化学物理研究所 | A kind of combination electrode and its preparation and application |
| CN105514378A (en) * | 2015-12-22 | 2016-04-20 | 湘潭大学 | Lithium-sulfur battery positive-pole composite material with imitated cellular structure and preparation method thereof |
| CN108987725A (en) * | 2018-08-21 | 2018-12-11 | 南开大学 | A kind of anode composite material of lithium sulfur battery and preparation method thereof |
| CN109585828A (en) * | 2018-11-29 | 2019-04-05 | 济南大学 | RGO/VS is prepared in situ in one-step method4/ S compound is as lithium sulfur battery anode material |
| CN109755553A (en) * | 2019-03-20 | 2019-05-14 | 北京航空航天大学 | A kind of magnesium lithium Dual-ion cell composite positive pole and its preparation method and application, battery system |
Non-Patent Citations (1)
| Title |
|---|
| Lithium storage performance and mechanism of VS4/rGO as an electrode material associated with lithium-sulfur batteries;LiyaZhu等;《Journal of Alloys and Compounds》;20190123;第785卷;第855-861页 * |
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