KR20180017654A - Cathode for lithium-sulfur battery comprising secondary particle of carbon, manufacturing method thereof and lithium-sulfur battery comprising the same - Google Patents

Abstract

The present invention relates to a high loading positive electrode applying carbon-based secondary particles and a sulfur complex, a manufacturing method thereof and a lithium-sulfur battery comprising the same. A lithium-sulfur battery according to the present invention improves loading of an electrode since energy density is increased due to carbon-based materials in a secondary particle structure, and improves initial capacity. Also, even if a high loading electrode is realized, problems such as cracks of an electrode or separation from a current collector and a battery short circuit do not occur.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive electrode for a lithium-sulfur battery including a carbon-based secondary particle, a method for producing the same, and a lithium-sulfur battery including the same,

The present invention relates to a positive electrode for a lithium-sulfur battery including carbon-based secondary particles, and more particularly, to a high-loading positive electrode to which a composite of a plurality of primary particles and aggregated spherical carbon- And a lithium-sulfur battery including the same.

In recent years, miniaturization and weight reduction of electronic products, electronic devices, and communication devices are rapidly proceeding. As the necessity of electric automobiles has been greatly increased with respect to environmental problems, there has been an increase in demand for performance improvement of secondary batteries used as power sources for these products . Among them, lithium secondary batteries are attracting considerable attention as high performance batteries due to high energy density and high standard electrode potential.

In particular, a lithium-sulfur (Li-S) battery is a secondary battery in which a sulfur-based material having a sulfur-sulfur bond is used as a cathode active material and lithium metal is used as an anode active material. Sulfur, the main material of the cathode active material, is very rich in resources, has no toxicity, and has a low atomic weight. The theoretical energy density of the lithium-sulfur battery is 1675 mAh / g-sulfur and the theoretical energy density is 2,600 Wh / kg. The theoretical energy density (Ni-MH battery: 450 Wh / , Which is the most promising among the batteries that have been developed to date, because it is much higher than the FeS battery (480Wh / kg), Li-MnO ₂ battery (1,000Wh / kg) and Na-S battery (800Wh / kg).

The lithium-sulfur battery has been studied as a next-generation battery using a high theoretical capacity and a higher energy density than a lithium ion battery, and its application field is gradually expanding. In order to increase the energy density of a lithium-sulfur battery, it is necessary to manufacture a high loading electrode which realizes a high capacity. In order to satisfy such a high efficiency lithium-sulfur battery characteristic, a capacity per unit weight or a high efficiency per unit volume of the electrode active material and a high packing density are required.

Korean Patent Laid-Open Publication No. 2016-0042622 "A method for producing a porous electrode active material, a porous electrode active material prepared thereby, a porous electrode active material, an electrode including the same and a secondary battery &

As described above, when the amount of loading of the active material per unit area of the anode is increased in order to satisfy the characteristics of the lithium-sulfur battery with high efficiency, cracks are generated, or when the sheet- There is a problem that a crack is generated in the portion and short-circuiting occurs. The inventors of the present invention conducted various studies to solve such problems and found that the above problem can be solved by preparing a carbon-based material, which is a cathode composition, as a secondary particle, and completed the present invention.

Accordingly, it is an object of the present invention to provide a high loading electrode having high capacity per unit weight or high efficiency per unit volume of electrode active material and high packing density, and it is possible to prevent electrode cracking, And the like.

To achieve the above object, the present invention provides a positive electrode for a lithium-sulfur battery including a spherical carbon-based secondary particle and sulfur containing a plurality of primary particles assembled and agglomerated.

The present invention also provides a method for producing a positive electrode for a lithium-sulfur battery.

The present invention also provides a lithium-sulfur battery including the positive electrode.

Since the lithium-sulfur battery according to the present invention has a high energy density due to the carbon-based material having the secondary particle structure, the loading of the electrode is improved and the initial capacity is also improved. Also, even if a high loading electrode is implemented, there is no problem such as cracking of the electrode, detachment from the current collector and short-circuit of the battery.

1 is a scanning electron microscope (SEM) image of an S / KB-2 composite prepared according to Example 1 of the present invention.
2 is a scanning electron microscope (SEM) image of the S / KB-1 complex prepared according to Comparative Example 1 of the present invention.
FIG. 3 is an optical microscope image of a cathode manufactured according to Example 1 of the present invention. FIG.
4 is an optical microscope image of a positive electrode prepared according to Comparative Example 1 of the present invention.
5 is an optical microscope image of a positive electrode prepared according to Comparative Example 2 of the present invention.
6 is charge / discharge data of a lithium-sulfur battery manufactured according to Example 2 and Comparative Example 3 of the present invention.

Hereinafter, the present invention will be described in detail.

The present invention discloses a positive electrode for a lithium-sulfur battery comprising a spherical carbon-based secondary particle and a sulfur which are aggregated with a plurality of primary particles assembled together.

As used herein, the term "initial particle" means the original particle when a different kind of particle is formed from a particle, and "secondary particles" Quot; means a physically distinguishable large particle formed by aggregation, bonding, or granulation.

As used herein, the term "primary particle assembly" refers to a process in which primary particles spontaneously or artificially flocculate or aggregate to form an aggregate of a plurality of primary particles, thereby forming a secondary particle. Or a combination thereof.

The carbonaceous material applicable to the present invention is not limited in its kind, but natural graphite, artificial graphite, expanded graphite, Graphene, Graphene oxide, Super-P, Graphite systems such as Super-C; Active carbon system; Denka black, Ketjen black, Channel black, Furnace black, Thermal black, Contact black, Lamp black, Acetylene A carbon black system such as black (Acetylene black); Carbon nanotubes such as carbon fiber, carbon nanotube (CNT), and fullerene; And a combination thereof, and preferably a carbon black system is used.

The average particle diameter of the carbon-based primary particles varies depending on the kind of the carbon-based material. For example, the average particle diameter of the carbon-based primary particles may be 10 to 100 nm in the case of carbon black. In the case of carbon nanotubes, Can be selected to be 1 to 30 占 퐉, but it is not limited thereto.

Generally, when a composite of carbon-based primary particles and sulfur (S) is used as a positive electrode composition of a lithium-sulfur battery, since particles are randomly entangled with each other, when loaded at a high capacity, cracks are generated, The efficiency is low.

However, according to the present invention, when the carbon-based particles are secondary-granulated and then sulfur is added to form a composite, the secondary particle structure can be maintained well and the electrode can be manufactured with high loading, . Specifically, the carbon-based secondary particles according to the present invention have excellent rolling properties due to micropores present therein, and thus can be densified. The fine pores in the carbon-based secondary particles can serve as a microscopic buffer, and when used in combination with sulfur, they can have excellent rolling properties without being deformed or decomposed even in a relatively strong rolling, It is possible to increase the density of the semiconductor device. According to the present invention, it is possible to produce a positive electrode having a high loading amount of 1.0 to 10.0 mAh / cm < 2 >

In consideration of the slurry mixing and the smoothness of the surface of the electrode, the carbon-based secondary particles preferably have an average particle diameter of 1 to 50 mu m. If the average particle diameter exceeds the above range, the porosity between the secondary particles increases and the tap density decreases, and the slurry mixing and sedimentation phenomenon gradually occurs. On the contrary, when the average particle diameter is less than the above range, It can be prepared within the above range.

In addition to the pores of the primary particles, the carbon-based secondary particles have porosity due to the texture pores generated during agglomeration of the primary particles, which can be measured by BET analysis. The measured pore volume may range from about 0.2 to 4.0 cm ³ / g, and the specific surface area may be from 100 to 2000 m ² / g.

The carbon-based secondary particles are preferably combined with sulfur (S), which is a cathode active material, and applied as a cathode composition for a lithium-sulfur battery. The sulfur (S) includes elemental sulfur (S8), a sulfur-based compound, or a mixture thereof. The sulfur-based compound is particularly, solid Li ₂ S _{n (n} ≥1) is dissolved kaessol light (Catholyte), organic sulfur compounds, and carbon-sulfur polymer _{[(C 2 S x) n} , x = 2.5 to 50, n > = 2].

At this time, the weight ratio of the carbon-based material and sulfur (S) in the composite may be adjusted to be 5: 5 to 1: 9. The above range is a content range capable of sufficiently performing the function as an electrode active material and ensuring electron conductivity by the carbon-based material (C). If the content of sulfur is less than the above range, the amount of active material suitable for a high energy density battery can not be secured at the anode. On the other hand, when sulfur is used in excess of the above range, sulfur is molten and sulfur, They are bundled together and are difficult to receive electrons, so that it is difficult to directly participate in the electrode reaction, which may lead to deterioration of the battery performance.

When a composite of the above-described carbon-based material and sulfur is used as the positive electrode composition of a lithium-sulfur battery, the composite of the carbon-based material and sulfur may be used alone, or in addition to the composite of the carbon- Conducting material, binder, filler, etc. may be further added.

The conductive material serves as a path through which electrons move from the current collector to the sulfur, thereby not only imparting electron conductivity, but also electrically connecting the electrolyte and the cathode active material to form a lithium ion (Li ⁺ ) dissolved in the electrolyte Sulfur, and react to the reaction.

Therefore, if the amount of the conductive material is insufficient or does not perform properly, the portion of the sulfur in the electrode that does not react increases and eventually the capacity decreases. In addition, the high rate discharge characteristics and the charge / discharge cycle life are adversely affected. Therefore, it is necessary to add an appropriate conductive material. The conductive material is preferably added in an amount of 0.01 to 30% by weight based on the total weight of the cathode composition.

The conductive material is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery, for example, graphite; Carbon black such as Denka black, acetylene black, Ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskers such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used. Concrete examples of commercially available conductive materials include acetylene black series such as Chevron Chemical Company, Denka Singapore Private Limited, Gulf Oil Company, Ketjenblack, Armak Company products, Vulcan XC-72 Cabot Company products and Super-P (Timcal) products can be used.

The binder is a component that assists in bonding of the active material and the conductive material and bonding to the current collector, and is usually added in an amount of 1 to 50 wt% based on the total weight of the mixture containing the electrode active material. If the content of the binder resin is less than 1% by weight, the physical properties of the positive electrode may deteriorate and the positive electrode active material and the conductive material may fall off. When the amount of the binder resin exceeds 50% by weight, the ratio of the active material and the conductive material in the positive electrode is relatively decreased The battery capacity can be reduced.

The binder applicable to the present invention may be any binder known in the art and specifically includes a fluororesin binder containing polyvinylidene fluoride (PVdF) or polytetrafluoroethylene (PTFE) ; Rubber-based binders including styrene-butadiene rubber, acrylonitrile-butadiene rubber, and styrene-isoprene rubber; Cellulosic binders including carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, and regenerated cellulose; Polyalcohol-based binders; Polyolefin binders including polyethylene and polypropylene; But are not limited to, polyimide-based binders, polyester-based binders, and silane-based binders, or a mixture or copolymer of two or more thereof.

The filler is not particularly limited as long as it is a fibrous material without causing any chemical change in the battery, and examples thereof include oligomer polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

Manufacturing method

The most preferred method for producing the carbon-based secondary particles of the present invention is the spray drying method. First, a carbon-based material is selected, mixed with a predetermined solvent to prepare a solution, and the solution is injected into nano-sized fine droplets to prepare a secondary particle form.

More specifically, the carbon-based secondary particles have a particle diameter

I) diluting a carbon-based powder as a primary particle in a solvent to prepare a spray liquid;

Ii) feeding the spray liquid into a spray chamber; And

And (iii) spray-drying the sprayed liquid to prepare carbon-based secondary particles.

The spray drying apparatus may be a conventional spray drying apparatus, for example, an ultrasonic spray drying apparatus, an air nozzle spray drying apparatus, an ultrasonic nozzle spray drying apparatus, a filter expansion droplet generating apparatus or an electrostatic spray drying apparatus May be used, but is not limited thereto.

The solvent for diluting the carbon-based powder may be any one of water, methanol, ethanol, isopropyl alcohol, and acetone, but is not limited thereto and may be a solvent capable of evenly dispersing the carbon-based powder. In addition, a predetermined dispersing agent may be further added for strengthening the bonding force between the primary particles and dispersing the primary particles.

According to an embodiment of the present invention, the content of the solid content in the spray liquid is 0.5 to 40% by weight, and more preferably 15 to 30% by weight. This can be prepared by suitably controlling the carbon content of the primary particles.

In spray drying, the drying temperature may vary depending on the solvent used, and may be, for example, from 100 to 220 ° C, and the spraying pressure may be from 1.5 to 3 bar, but is not limited thereto . In addition, the rate of supplying the spraying liquid can be adjusted up to 10 ml / min, which may vary depending on the pressure-reducing pressure.

After the secondary particles are prepared, a carbonization process at 400 to 900 ° C. for about 2 to 10 hours may be further performed to strengthen the bonding force between primary particles and to remove the dispersant used for primary particle dispersion.

The carbon-based secondary particles can be compounded with sulfur according to a conventional method. For example, the process of dissolving sulfur in the organic solvent to fill the pore volume of the carbon-based secondary particles and drying the solvent is repeated several times, Impregnation method, and a melt-diffusion method in which sulfur is dissolved by heating at a melting point (about ~ 115 ° C) and then impregnated by capillary phenomenon of pore volume.

The thus-prepared carbon / sulfur composite can be prepared by mixing a conductive material and a binder in an organic solvent to prepare a cathode composition, coating the collector on the collector, drying the mixture, and selectively compressing the collector to improve the electrode density .

At this time, it is preferable that the organic solvent, the cathode active material, the binder and the conductive material can be uniformly dispersed and easily evaporated. Specific examples thereof include acetonitrile, methanol, ethanol, tetrahydrofuran, water, isopropyl alcohol and the like.

The current collector generally has a thickness of 3 to 500 μm and is not particularly limited as long as it has high conductivity without causing chemical change in the battery. Specifically, a conductive material such as stainless steel, aluminum, copper, or titanium can be used, and more specifically, a carbon-coated aluminum current collector can be used. The use of a carbon-coated aluminum substrate is advantageous in that it has an excellent adhesion to an active material, has a low contact resistance, and can prevent corrosion caused by aluminum polysulfide, as compared with a carbon-coated aluminum substrate. The current collector may be in various forms such as a film, a sheet, a foil, a net, a porous body, a foam or a nonwoven fabric.

The slurry may be coated on the current collector with an appropriate thickness according to the viscosity of the slurry and the thickness of the anode to be formed, and may be suitably selected within the range of 100 to 200 mu m.

The slurry may be coated by a method such as doctor blade coating, dip coating, gravure coating, slit die coating, spin coating, Spin coating, comma coating, bar coating, reverse roll coating, screen coating, cap coating and the like.

Further, by replacing the existing liquid phase process in which a problem such as a high temperature, a variety of organic matter residues, and a long reaction time is brought about in order to obtain a nano-sized powder having a uniform composition and a coagulated material, Of the nano-sized powder and the agglomerate structure made of the nano-sized powder can be easily synthesized.

Furthermore, it is possible to obtain secondary battery powders having various aggregate structures easily by controlling the composition of the spraying solution used in the spray drying process, and the size of the agglomerate powder can be easily controlled by adjusting the concentration of the slurry.

The positive electrode of the lithium-sulfur battery according to the present invention typically comprises a composite of a carbon-based secondary particle and sulfur on a current collector, and for example, a binder and a solvent, and a conductive material and a dispersant, Followed by stirring to prepare a slurry, which is then applied to a current collector of a metal material, followed by rolling and drying.

Lithium-sulfur battery

The lithium-sulfur battery according to the present invention comprises a positive electrode containing carbon-based secondary particles and sulfur; A negative electrode comprising lithium metal or a lithium alloy; A separator interposed between the anode and the cathode; And an electrolyte.

In particular, the lithium-sulfur battery of the present invention suppresses elution of lithium polysulfide, thereby improving the electrode loading and initial discharge capacity, and ultimately increasing the energy density of the lithium-sulfur battery. As a result, the lithium-sulfur battery is preferably applicable as a high-density battery or a high-performance battery.

The negative electrode active material of the lithium-sulfur battery according to the present invention may be one selected from the group consisting of lithium metal, lithium alloy, lithium metal composite oxide, lithium-containing titanium composite oxide (LTO), and combinations thereof. The lithium alloy may be an alloy of lithium and at least one metal selected from Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Al and Sn. In addition, lithium metal composite oxide is lithium and Si, Sn, Zn, Mg, Cd, Ce, Ni, and is one of a metal (Me) oxide (MeO _x) selected from the group consisting of Fe, for example in Li _x Fe ₂ O ₃ (0 < x? 1) or Li _x WO ₂ (0 <x? 1).

The separation membrane of the lithium-sulfur battery according to the present invention is a physical separator having a function of physically separating an electrode, and can be used without any particular limitation as long as it is used as a conventional separator. Particularly, It is preferable that the wetting ability is excellent.

In addition, the separator separates or insulates the positive electrode and the negative electrode from each other, and enables transport of lithium ions between the positive electrode and the negative electrode. Such a separator may be made of a porous, nonconductive or insulating material. The separator may be an independent member such as a film, or a coating layer added to the anode and / or the cathode.

Specifically, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer and an ethylene / methacrylate copolymer may be used alone Or they may be laminated. Alternatively, nonwoven fabrics made of conventional porous nonwoven fabrics such as glass fibers of high melting point, polyethylene terephthalate fibers and the like may be used, but the present invention is not limited thereto.

The electrolyte of the lithium-sulfur battery according to the present invention is a non-aqueous electrolyte containing a lithium salt, which is composed of a lithium salt and an electrolyte. Non-aqueous organic solvents, organic solid electrolytes, and inorganic solid electrolytes are used as the electrolyte.

The lithium salt of the present invention can be dissolved in a non-aqueous organic solvent, for example, LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiB (Ph) _{4 ,} LiPF ₆ , LiCF ₃ SO ₃ , _{LiCF 3 CO 2, LiAsF 6,} LiSbF 6, LiAlCl 4, LiSO 3 CH 3, LiSO 3 CF 3, LiSCN, LiC (CF 3 SO 2) 3, LiN (CF 3 SO 2) 2, chloroborane lithium, lower aliphatic Lithium tetraborate, lithium tetraborate, lithium tetraborate, lithium tetraborate, lithium tetraborate, lithium tetraborate, and lithium imide.

The concentration of the lithium salt may be 0.2 to 2 M according to various factors such as the precise composition of the electrolyte mixture, the solubility of the salt, the conductivity of the dissolved salt, the charging and discharging conditions of the battery, the working temperature and other factors known to the lithium battery May be 0.6 to 2M, more specifically 0.7 to 1.7M. If it is used at less than 0.2 M, the conductivity of the electrolyte may be lowered and the performance of the electrolyte may be deteriorated. If it is used in excess of 2 M, the viscosity of the electrolyte may increase and the mobility of lithium ions (Li ⁺ ) may be reduced.

The non-aqueous organic solvent should dissolve the lithium salt well. Examples of the non-aqueous organic solvent of the present invention include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate Dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, gamma-butylolactone, 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydroxyfuran, But are not limited to, tetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, 4-methyl-1,3-dioxolane, diethylether, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate , Methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, ether , Methyl pyrophosphate, ethyl propionate and the like Castle, an organic solvent may be used, the organic solvent may be a mixture of one or two or more organic solvents.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, A polymer including a group can be used.

Examples of the inorganic solid electrolyte of the present invention include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides and sulfates of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ can be used.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.

&Lt; Examples 1 and 2 >

Secondary particles (KB-2) of Ketjen black were prepared by introducing a spray drying process, and then impregnated with sulfur (S) to prepare S / KB-2 composite.

A slurry was prepared by mixing the S / KB-2 composite material: conductive material: binder in a composition of 90: 5: 5 to prepare a positive electrode. Denka black was used as the conductive material and CMC / SBR was used as the binder. The loading amounts were 7.47 mAh / cm2 and 4.3 mAh / cm2, respectively.

&Lt; Comparative Examples 1 to 3 >

Primary particles (KB-1) of Ketjenblack were mixed with sulfur (S) to prepare S / KB-1 composite.

The prepared S / KB-1 composite was formed by the same composition and method as in Example 1 to prepare a positive electrode, and the loading amounts were 4.785 mAh / cm 2, 2.275 mAh / cm 2, and 1.9 mAh / cm 2, respectively.

<Experimental Example 1>

SEM images of the S / KB-2 composite prepared in Examples 1 and 2 and the S / KB-1 composite prepared in Comparative Examples 1 to 3 are shown in FIGS. 1 and 2, respectively. In the case of the S / KB-1 composite without secondary granulation shown in FIG. 2, S and KB are randomly entangled. However, in the case of the S / KB-2 composite secondary particle, It was confirmed that it maintained well.

<Experimental Example 2>

An anode having a loading amount of 7.47 mAh / cm 2 prepared in Example 1, an anode having a loading amount of 4.785 mAh / cm 2 prepared in Comparative Example 1 and a loading amount of 2.275 mAh / cm 2 prepared in Comparative Example 2 were observed under an optical microscope An image is shown in Figs. 3 to 5. Fig. In the case of S / KB-1 composite electrodes of Comparative Examples 1 and 2 which were not subjected to secondary granulation, cracks occurred at low loading in the optical microscope photograph, and cracks were more intensified as the loading amount was increased. On the other hand, / KB-2 composite electrode, it was possible to manufacture a high loading electrode and no crack occurred.

<Experimental Example 3>

100 μl of DEGDME: DOL = 6: 4, 1 M LiFSI, 1% LiNO ₃ electrolyte containing the anode prepared according to Example 2 and Comparative Example 3 was poured into a Coin cell 2032 type lithium-sulfur battery was prepared.

Comparative Example In the case of the S / KB-1 composite electrode, cracks were severely generated and the high loading cell could not be driven, so that the loading as in the embodiment could not be compared. Therefore, a lithium-sulfur battery was fabricated using electrodes of Example 2 (loading: 4.3 mAh / cm 2) and Comparative Example 3 (loading: 1.9 mAh / cm 2), and their charge and discharge characteristics are shown in FIG. By comparing the initial capacities, it was confirmed that the initial capacity was better in Example 2, which was made from secondary particles, despite the high loading.

Claims (11)

Spherical carbon-based secondary particles in which a plurality of primary particles are assembled and aggregated; And
Anodes for lithium-sulfur batteries containing sulfur.
The method according to claim 1,
Wherein the average particle diameter of the carbon-based secondary particles is 1 to 50 占 퐉.
The method according to claim 1,
Wherein the pore volume of the carbon-based secondary particles is about 0.2 to 4.0 cm &lt; ³ &gt; / g.
The method according to claim 1,
Wherein the specific surface area of the carbon-based secondary particles is 100 to 2000 m ² / g.
The method according to claim 1,
The carbon-based secondary particles include natural graphite, artificial graphite, expanded graphite, Graphene, Graphene oxide, Super-P and Super-C. Graphite system; Active carbon system; Denka black, Ketjen black, Channel black, Furnace black, Thermal black, Contact black, Lamp black and Acetylene A carbon black system including black (Acetylene black); A carbon nanostructure including a carbon fiber system, a carbon nanotube (CNT), and a fullerene; And combinations thereof. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
The method according to claim 1,
Wherein the weight ratio of the carbon-based secondary particles to sulfur is 5: 5 to 1: 9.
The method according to claim 1,
Wherein the loading amount of the positive electrode is 1.0 to 10.0 mAh / cm &lt; 2 &gt;.
A method for producing a positive electrode for a lithium-sulfur battery in which a positive electrode composition containing sulfur and a carbon-based material is coated on a current collector,
The carbon-
I) diluting a carbon-based powder as a primary particle in a solvent to prepare a spray liquid;
Ii) feeding the spray liquid into a spray chamber; And
Iii) spray-drying the sprayed liquid to prepare carbon-based secondary particles;
The method of manufacturing a positive electrode for a lithium-sulfur battery according to claim 1,
9. The method of claim 8,
The method for producing a positive electrode for a lithium-sulfur battery according to any one of claims 1 to 3, wherein the solid content of the spray liquid in step (i) is 0.5 to 30 wt%.
9. The method of claim 8,
Wherein the temperature of spray drying in step iii) is 100 to 220 ° C and the spray pressure is 1.5 to 3 bar.
anode; cathode; A lithium-sulfur battery comprising an electrolyte disposed therebetween,
The lithium-sulfur battery according to any one of claims 1 to 7, wherein the positive electrode is a positive electrode.

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