KR100766981B1 - Cathode active material for lithium secondary battery, lithium secondary battery comprising the same, and method for preparing lithium secondary battery - Google Patents

Abstract

The present invention relates to a cathode active material for a lithium secondary battery, a lithium secondary battery comprising the same, and a method of manufacturing a lithium secondary battery, wherein the cathode active material includes an active material capable of intercalation and deintercalation of lithium; And polyether modified silicone oil supported on the active material.

The positive electrode active material of the present invention can prevent deterioration of the positive electrode active material due to charging, and is excellent in cycle characteristics and safety during charging with a high capacity.

Lithium Secondary Battery, Cathode Active Material, Polyether Modified Silicone Oil, Silicone Oil

Description

A cathode active material for a lithium secondary battery, a lithium secondary battery comprising the same, and a method of manufacturing a lithium secondary battery TECHNICAL FIELD

1 is a schematic cross-sectional view of a lithium secondary battery according to an embodiment of the present invention.

[Industrial use]

The present invention relates to a positive electrode active material for a lithium secondary battery, a lithium secondary battery comprising the same, and a method for producing a lithium secondary battery, and more particularly, to a lithium secondary battery having high capacity and excellent cycle characteristics.

[Prior art]

BACKGROUND ART Lithium secondary batteries are widely used as power sources for electronic devices such as mobile phones, digital still cameras, digital video cameras, and notebooks. Conventionally, as a lithium secondary battery, a battery is known in which LiCoO ₂ is used as a positive electrode active material, graphite is used as a negative electrode active material, and a nonaqueous solution is used as an electrolyte.

In recent years, as the use power of electronic devices increases, higher capacity of lithium secondary batteries is increasingly required. Accordingly, research on a negative electrode active material having Si as a main component instead of graphite is being conducted. Since the negative electrode active material containing Si as a main component has a charge and discharge capacity close to 10 times that of graphite, it is promising as a future electrode material. However, a negative electrode active material containing Si as a main component has problems such as formation of an alloy of Si and lithium during charging, expansion of its volume, and decomposition of the electrolyte.

In order to solve this problem, a negative electrode active material which is made of polyphase alloy powder containing Si as a main component but with Si removed thereon has been developed (Japanese Patent Laid-Open No. 2005-071772), and the practical use of a negative electrode active material containing Si Is becoming a reality.

In the conventional lithium secondary battery, when Li is deintercalated from the positive electrode active material by charging, the positive electrode active material is in an electrochemically unstable state, and metals such as Co constituting the positive electrode active material are eluted to deteriorate the positive electrode active material. There was a problem. When the positive electrode active material deteriorates, cycle characteristics deteriorate and safety during charging deteriorates. In addition, since the deterioration of the positive electrode active material is more remarkable at higher capacity, it is difficult to obtain a lithium secondary battery having high capacity and excellent cycle characteristics and safety during charging.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent deterioration of a positive electrode active material during charging, and to have a high capacity, a cathode active material for a lithium secondary battery having excellent cycle characteristics and safety during charging, including the same. It is to provide a lithium secondary battery and a method for producing a lithium secondary battery.

In order to achieve the above object, the present invention is an active material capable of intercalation and deintercalation of lithium; And it provides a cathode active material for a lithium secondary battery comprising a polyether modified silicone oil (油) supported on the active material.

The polyether-modified silicone oil is a compound selected from the group consisting of compounds of the following Formulas 1 to 5, and combinations thereof.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

(In Formulas 1 to 5, k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n has a range of 1 to 2, R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Is either one)

The polyether-modified silicone oil is preferably contained in 0.001 to 10% by mass based on the total mass of the positive electrode active material.

The polyether-modified silicone oil is preferably impregnated with an active material capable of intercalation and deintercalation of the lithium.

The present invention also includes a positive electrode comprising the positive electrode active material; A negative electrode including a negative electrode active material capable of intercalation and deintercalation of lithium; And it provides a lithium secondary battery comprising a non-aqueous electrolyte.

It is preferable that the said negative electrode active material contains Si as a main component.

The present invention also provides a method of manufacturing a lithium secondary battery comprising the step of applying a positive electrode slurry containing the positive electrode active material to a positive electrode current collector to produce a positive electrode.

In the method of manufacturing the lithium secondary battery, the positive electrode slurry is coated on a positive electrode current collector, and then immersed in a polyether-modified silicone oil selected from the group consisting of the compounds of Formulas 1 to 5, and a combination thereof, or a solution containing the same. Or by applying the same to prepare a positive electrode.

Hereinafter, the present invention will be described in more detail.

A lithium secondary battery according to an embodiment of the present invention includes a positive electrode, a negative electrode, and an electrolyte.

(anode)

Examples of the positive electrode include a positive electrode material containing a positive electrode active material, a conductive agent, and a binder; And a positive electrode current collector bonded to the positive electrode mixture can be used. In addition, a pellet-like or sheet-like electrode formed by forming the cathode mixture in a disc shape can be used.

In the lithium secondary battery of the present invention, polyether-modified silicone oil is supported on the positive electrode active material constituting the positive electrode. The polyether modified silicone oil supported on the positive electrode active material refers to a state in which polyether modified silicone oil is soaked in the positive electrode active material itself, or a state in which polyether modified silicone oil is coated on the surface of the positive electrode active material.

The positive electrode active material is composed of an active material capable of intercalation and deintercalation of lithium. Such active materials include compounds including Li, oxides, sulfides, and the like. The positive electrode active material may further include metals such as Mn, Co, Ni, Fe, and Al. With the active material such as _{LiMn 2 O 4, LiCoO 2,} LiNiO 2, LiFeO 2, LiNi 1/3 Co 1/3 Mn 1/3 O 2, LiNi 0 .8 Co 0 .2 O 2 is preferred. Moreover, as a binder, polyvinylidene fluoride, polytetrafluoro ethylene, etc. are preferable. Moreover, as a conductive agent, carbon black, KETJEN BLACK, graphite, etc. are preferable. Moreover, as a positive electrode collector, metal foil or a metal net which consists of aluminum, stainless steel, etc. is preferable.

As the polyether-modified silicone oil, polyether-modified silicone oil containing a compound selected from the group consisting of compounds represented by the above formulas (1) to (5), and combinations thereof can be used. The polyether-modified silicone oils of the above formulas (1) to (5) include one to _two linear polysiloxane chains (SiR ₂ -O- (SiR ₂ O-) _k -SiR ₂ ) or cyclic polysiloxanes. Polyether chain [(-(CH ₂ ) _l- (CH (CH ₃ ) CH ₂ ) _m -O- (C ₂ H ₄ 0) _n -Z) or (-(CH ₂ ) _l- (CH (CH ₃ ) CH ₂ ) _m -O- (C ₂ H ₄ 0) _n- (CH ₂ CH (CH ₃ )) _m- (CH ₂ ) _l )-] is a bond. The polyether-modified silicone oils of the formulas (1) to (5) have high thermal stability because they have a linear or cyclic polysiloxane chain.

In the polyether-modified silicone oil of the above formulas (1) to (5), k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n is Has a range of 1-2 and R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Either.

Thermal stability improves when K exceeds 9, but there exists a problem that a viscosity becomes high, and when manufacturing with a battery, since electrolyte solution becomes difficult to penetrate, it is unpreferable. Moreover, when k is less than 1, silicone oil is easy to decompose, and it is unpreferable.

When l exceeds 3, there is a problem that the viscosity becomes high, and when the battery is manufactured, it is not preferable because the electrolyte solution becomes difficult to penetrate.

Even when m exceeds 1, there is a problem that the polyether chain is long and the viscosity is high, and when the battery is manufactured, the electrolyte solution becomes difficult to penetrate, which is not preferable.

When n is less than 1, silicone oil is liable to decompose and is not preferable. When n exceeds 2, there is a problem in that the polyether chain is long and the viscosity becomes high. In the case of producing a battery, the electrolyte solution becomes difficult to penetrate, which is not preferable.

R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ In any case, since the synthesis | combination of a polyether modified silicone oil becomes easy, it is preferable.

The amount of the polyether-modified silicone oil supported on the positive electrode active material is preferably in the range of 0.001% by mass to 10% by mass, and more preferably in the range of 0.001% by mass to 5% by mass with respect to the positive electrode active material. When the amount of polyether modified silicone oil is less than 0.001 mass% with respect to the positive electrode active material, the effect of preventing the deterioration of the positive electrode is not sufficiently obtained, and when the amount of polyether modified silicone oil exceeds 10 mass% with respect to the positive electrode active material, the electrolyte The contact between the positive electrode active material and the positive electrode active material is undesirably interrupted and the charge and discharge efficiency is lowered.

As a method of supporting the polyether-modified silicone oil on the active material, any method conventionally used may be used. For example, a positive electrode mixture including the active material, a conductive agent, and a binder is coated on a current collector to prepare a positive electrode, and the polyether modified silicone oil is added to the positive electrode by immersing the positive electrode in polyether modified silicone oil. After supporting, the method of drying can be used. In this case, instead of polyether-modified silicone oil, a solution containing polyether-modified silicone oil and a solvent may be used, and then the method may be used in which the positive electrode is immersed in the solution, followed by drying and volatilizing the solvent.

The solvent may be any solvent so long as it can dissolve the polyether-modified silicone oil such as carbonate solvent (dimethyl carbonate, diethyl carbonate, etc.) used in a battery electrolyte solution, acetone, ether, alcohol, and the like. However, since a solvent may remain, it is preferable to use the solvent used as a battery electrolyte solution. Moreover, since a high boiling point and a nonvolatile solvent are easy to handle, it is more preferable to use a high boiling point and a nonvolatile solvent.

As another method of supporting the polyether-modified silicone oil in the active material, for example, the active material, the conductive agent, and the binder in which the polyether-modified silicone oil is impregnated with the active material is impregnated with the polyether-modified silicone oil. And a positive electrode mixture comprising a positive electrode mixture containing a solvent such as N-methyl-2-pyrrolidone to prepare a positive electrode slurry, the positive electrode slurry is applied onto a current collector, and dried to volatilize the solvent.

As another method of supporting the polyether-modified silicone oil on the active material, for example, a positive electrode mixture containing the active material, a conductive agent, and a binder may be added together with N-methyl-2- with polyether-modified silicone oil. The positive electrode slurry is manufactured by mixing with solvents, such as a pyrrolidone, and apply | coating the said positive electrode slurry on an electrical power collector, and then drying and volatilizing a solvent is mentioned.

Method for producing a polyether-modified silicone oil is obtained by replacing a part with respect to a polysiloxane of the group consisting of hydrogen, for example, reacting a polyether compound containing a double bond such as (CH ₂ = CH-).

In addition, the polyether-modified silicone oil prepared as described above contains Pt (platinum) as a catalyst component and butylated hydroxy toluene (BHT) as a polymerization inhibitor in several to several tens of ppm. Since Pt and BHT are substances which adversely affect the cycle characteristics, it is preferable to remove them as much as possible. In this invention, it is preferable that Pt contained in a polyether modified silicone oil is at least 5 ppm, and BHT is less than 60 ppm, and it is more preferable that Pt and BHT are respectively below a detection limit.

(cathode)

Examples of the negative electrode include a negative electrode mixture containing a negative electrode active material, a conductive agent, and a binder in the present invention; And a negative electrode current collector bonded to the negative electrode mixture can be used. In addition, a pellet-like or sheet-like electrode formed by forming the negative electrode mixture in a disc shape can be used.

The binder of the negative electrode may be any organic or inorganic material, as long as the binder is dispersed or dissolved in a solvent together with the negative electrode active material and the negative electrode active material can be bound by removing the solvent. It is also possible to mix the negative electrode active material by mixing with the negative electrode active material and performing solidification molding such as pressure molding. As such a binder, a vinyl resin, a cellulose resin, a phenol resin, a thermoplastic resin, a thermosetting resin, or the like is preferably used, and polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose, styrene butadiene rubber or the like is used. More preferably.

In addition to the negative electrode active material and the binder, carbon black, graphite powder, carbon fiber, metal powder, metal fiber and the like may be further added as a conductive agent.

Moreover, as a negative electrode collector, the metal foil or metal net manufactured from copper can be illustrated.

As the negative electrode active material, carbonaceous materials such as artificial graphite, natural graphite, graphitized carbon fibers, graphitized mesocarbon microbeads, and amorphous carbon may be used. In addition to the carbonaceous material, a metallic compound capable of alloying with lithium, or a composite containing a metallic compound and a carbonaceous material can also be used as the negative electrode active material. As a metal which can be alloyed with lithium, Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, Si alloy, Sn alloy, Al alloy, etc. can be illustrated. Moreover, a metal lithium thin film can also be used as a negative electrode active material.

(Nonaqueous electrolyte)

As the nonaqueous electrolyte, an organic electrolyte solution in which a lithium salt is dissolved in an aprotic solvent can be used.

As an aprotic solvent, propylene carbonate, ethylene carbonate, butylene carbonate, benzonitrile, acetonitrile, tetrahydrofuran, 2-methyltetrahydrofuran, γ-butyrolactone, dioxolane, 4-methyl dioxolane, N , N-dimethylformamide, dimethyl acetamide, dimethyl sulfoxide, dioxane, 1,2-dimethoxyethane, sulfolane, dichloroethane, chlorobenzene, nitrobenzene, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, methyl Aprotic solvents such as propyl carbonate, methyl isopropyl carbonate, ethyl butyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, diethylene glycol, dimethyl ether, or a mixed solvent in which two or more kinds of the above solvents are mixed. Preference is given to, in particular, propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC) Which it is more preferred to be included in either the one at the same time necessarily include dimethyl carbonate (DMC), methylethyl carbonate (MEC), diethyl carbonate (DEC).

Lithium salts include LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiAsF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, LiC ₄ F ₉ SO ₃ , LiSbF ₆ , LiAlO ₄ , LiAlCl ₄ , LiN (C _x F _{2x + 1} SO ₂ ) (C _y F _{2y +1} SO ₂ ) (where x, y is an integer), LiCl, LiI, etc. that it is more preferable to preferred, and include LiPF _6.

Instead of the non-aqueous electrolyte, a polymer electrolyte such as a mixture of any one of the lithium salts with a polymer such as PEO or PVA, or an organic electrolyte solution impregnated with a polymer having good swelling properties may be used.

In addition, the lithium secondary battery of the present invention not only includes the positive electrode, the negative electrode and the electrolyte, but may also include other members as necessary. A separator may be provided to isolate the positive and negative electrodes, which is essential when using a non-gelling nonaqueous electrolyte. As a separator, a well-known separator, such as a porous polypropylene film and a porous polyethylene film, can be used.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

1 is a schematic cross-sectional view of a rechargeable lithium battery according to one embodiment of the present invention.

Referring to FIG. 1, a lithium secondary battery according to an exemplary embodiment of the present invention is described. The lithium secondary battery 1 includes a positive electrode 11, a negative electrode 12, and a space between the positive electrode 11 and the negative electrode 12. The electrode assembly 14 including the existing separator 13 is placed in the case 15, and then the electrolyte is injected into the upper portion of the case 15 and sealed with the cap plate 16 and the gasket 17. .

Next, a charging reaction of a lithium secondary battery according to an embodiment of the present invention will be described.

The charging reaction generally proceeds as follows. When LiCoO ₂ is used as the active material, lithium ions are deintercalated from LiCoO ₂ by charging, and the deintercalated lithium ions are intercalated in the crystal of the negative electrode active material (for example, graphite). When charging is charged end of progress, a LiCoO ₂ Li _{0 .5} CoO ₂ An electrochemically unstable state such as Co, which is a state in which Co is liable to elute.

In the positive electrode active material according to the embodiment of the present invention, since the polyether-modified silicone oil is supported on the positive electrode active material, the surface of the positive electrode active material is prevented from contacting with the electrolyte, thereby preventing deterioration of the positive electrode active material during charging. Therefore, the lithium secondary battery according to the present invention has excellent cycle characteristics and safety during charging, and excellent safety even when overcharged.

In the lithium secondary battery according to the exemplary embodiment of the present invention, since the polyether-modified silicone oil is supported on the positive electrode active material, electrochemical stability of the positive electrode active material during charging is improved, and deterioration of the positive electrode active material is prevented. In addition, since the electrochemical stability of the positive electrode active material at the time of charging is improved and Li ions are easily deintercalated from the positive electrode active material, the cycle characteristics are improved.

When the lithium secondary battery according to one embodiment of the present invention uses a negative electrode active material containing Si as a main component, a battery having high capacity and excellent cycle characteristics and safety during charging can be obtained.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited by the following examples.

Example 1

Hereinafter, a method of manufacturing a lithium secondary battery according to an embodiment of the present invention will be described.

96 parts by mass of LiCoO ₂ as active material, 10 parts by mass of polyvinylidene fluoride as binder, and ₂ parts by mass of carbon powder (carbon black (trade name)) as a battery conduction aid, N-methyl-2 -Pyrrolidone was further added to prepare a positive electrode slurry. The prepared positive electrode slurry was apply | coated to the aluminum foil which is a collector using the doctor blade method, N-methyl- 2-pyrrolidone was dried and volatilized, and it rolled and manufactured the sheet-like electrode.

In addition, a polyether-modified silicone oil represented by the following formula (6) was added to dimethyl carbonate (DMC) as a solvent to prepare a 10 mass% silicone solution.

The electrode was immersed in the prepared silicone solution, and then dried to volatilize the solvent to prepare a positive electrode. On the other hand, the amount of polyether modified silicone oil supported on the positive electrode active material of the produced positive electrode was 0.5 mass% with respect to the positive electrode active material.

[Formula 6]

Hereinafter, a method of manufacturing a negative electrode active material consisting of a multiphase alloy powder according to an embodiment of the present invention will be described.

60 mass parts of mass Si, 30 mass parts of Ni powder, and 10 mass parts of Ag powder were mixed, it melt | dissolved by the high frequency heating method, and the molten alloy was manufactured.

The prepared molten alloy was quenched by a gas atomization method using helium gas to prepare a quench alloy powder having an average diameter of 10 m.

30 g of the prepared quenching alloy powder was added to 500 ml of 5N aqueous sodium hydroxide solution, and impregnated for 1 hour while stirring at room temperature slowly. Thereafter, the mixture was washed sufficiently with pure water so as not to have residual sodium, and dried, and then the particle size was adjusted to an average diameter of 12 m. A negative electrode active material consisting of a multiphase alloy powder was prepared in the same manner as described above.

The impregnated negative active material was observed with a scanning electron microscope. As a result, it was confirmed that the surface of the negative electrode active material had a porous structure. Moreover, IPC analysis was performed about the negative electrode active material. As a result, it was confirmed that the amount of Si decreased from 60 parts by mass to 50 parts by mass. In addition, the element distribution on the surface of the negative electrode active material was examined by energy dispersive X-ray (EDX). As a result, it was confirmed that Si existed only in the alloy phase of Ni and Si, and that there was almost no Si single phase which existed before the impregnation treatment.

A negative electrode slurry was prepared by mixing 70 parts by mass of the obtained negative electrode active material, 20 parts by mass of graphite powder having an average diameter of 3 μm, 10 parts by mass of polyvinylidene fluoride as a binder, and N-methyl-2-pyrrolidone. After apply | coating the said negative electrode slurry on 14-micrometer-thick Cu foil which is an electrical power collector by the doctor blade method, N-methyl- 2-pyrrolidone was dried and volatilized, and it rolled. In the same manner as described above to prepare a negative electrode according to an embodiment of the present invention.

Ethylene carbonate (EC) and diethyl carbonate (DEC) were mixed with EC: DEC = 30: 70 to prepare a mixed solvent, and LiPF ₆ was added to the mixed solvent to a concentration of 1.3 mol / L to prepare a nonaqueous electrolyte. Prepared.

The positive electrode and the negative electrode are cut out in a disc shape, the positive electrode and the negative electrode face each other, the porous separator made of polypropylene is interposed between the positive electrode and the negative electrode, and the positive electrode, the negative electrode and the separator are housed in a battery case. After pouring the electrolyte, the battery case was sealed to manufacture a coin-type lithium secondary battery.

(Comparative Example 1)

A negative electrode and a nonaqueous electrolyte were prepared in the same manner as in Example 1, except that a sheet-like electrode was prepared as in Example 1, the electrode was not immersed in polyether modified silicone oil, and a coin-type lithium secondary battery was prepared. Prepared.

The lithium secondary batteries of Example 1 and Comparative Example 1 were subjected to constant current charging at 0.2C until the battery voltage became 4.15V, and then constant voltage charging until 0.01C. Thereafter, constant current discharge was performed at 0.2C until the battery voltage became 5.75V. Subsequently, the above charging and discharging was performed for 100 cycles at 1C. The results are shown in Table 1.

On the other hand, Table 1 shows the capacity retention rate at 100 cycles when charging and discharging at 1 C is performed at a capacity of 100 cycles.

TABLE 1

Capacity retention rate (%) Example 1 84 Comparative Example 1 65

As shown in Table 1, it can confirm that the lithium secondary battery of Example 1 has a high capacity retention rate compared with the lithium secondary battery of Comparative Example 1. This is because the polyether-modified silicone oil is supported on the positive electrode active material of Example 1, and the result is that the degradation of the positive electrode active material due to the progress of the charge / discharge cycle is prevented.

All simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

In the lithium secondary battery of the present invention, a polyether-modified silicone oil containing a compound selected from the group consisting of a compound represented by the above formulas (1) to (5), and a combination thereof is supported on the positive electrode active material, thereby preventing deterioration of the positive electrode active material. The lithium secondary battery is excellent in cycle characteristics and safety at the time of charging even in the case of high capacity.

Claims (17)

Active materials capable of intercalation and deintercalation of lithium; And It includes a polyether modified silicone oil supported on the active material, The polyether-modified silicone oil is a positive electrode active material for a lithium secondary battery containing a compound selected from the group consisting of a compound of the formula 1 to 5, and combinations thereof. [Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

(In Formulas 1 to 5, k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n has a range of 1 to 2, R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Is either one) The method of claim 1, The polyether-modified silicone oil is a cathode active material for a lithium secondary battery that is contained in 0.001 to 10% by mass based on the total mass of the positive electrode active material. The method of claim 2, The polyether-modified silicone oil is a cathode active material for a lithium secondary battery that is contained in 0.001 to 5% by mass based on the total mass of the positive electrode active material. The method of claim 1, The polyether-modified silicone oil is a positive electrode active material for a lithium secondary battery that is impregnated with an active material capable of intercalation and deintercalation of lithium. A positive electrode including a positive electrode active material capable of intercalation and deintercalation of lithium; A negative electrode including a negative electrode active material capable of intercalation and deintercalation of lithium; And Includes nonaqueous electrolyte, The cathode active material may include an active material capable of intercalation and deintercalation of lithium; And a polyether-modified silicone oil supported on the active material, wherein the polyether-modified silicone oil includes a compound selected from the group consisting of compounds of Formulas 1 to 5, and combinations thereof . [Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

(In Formulas 1 to 5, k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n has a range of 1 to 2, R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Is either one) The method of claim 5, The negative active material is a lithium secondary battery containing Si as a main component. The method of claim 5, The polyether-modified silicone oil is a lithium secondary battery that is contained in 0.001 to 10% by mass based on the total mass of the positive electrode active material. The method of claim 7, wherein The polyether-modified silicone oil is a lithium secondary battery that is contained in 0.001 to 5% by mass based on the total mass of the positive electrode active material. The method of claim 5, The polyether modified silicone oil is impregnated with an active material capable of intercalation and deintercalation of lithium. Applying a positive electrode slurry containing a positive electrode active material to a positive electrode current collector to manufacture a positive electrode, The cathode active material may include an active material capable of intercalation and deintercalation of lithium; And It includes a polyether modified silicone oil supported on the active material, The polyether-modified silicone oil is a method for producing a lithium secondary battery comprising a compound selected from the group consisting of a compound of the formula 1 to 5, and combinations thereof. [Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

(In Formulas 1 to 5, k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n has a range of 1 to 2, R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Is either one) The method of claim 10, The polyether-modified silicone oil is a method for producing a lithium secondary battery that is contained in 0.001 to 10% by mass relative to the total mass of the positive electrode active material. The method of claim 11, The polyether-modified silicone oil is a manufacturing method of a lithium secondary battery that is contained in 0.001 to 5% by mass relative to the total mass of the positive electrode active material. The method of claim 10, The polyether-modified silicone oil is a method of manufacturing a lithium secondary battery that is impregnated with an active material capable of intercalation and deintercalation of lithium. After applying a positive electrode active material containing an active material capable of intercalation and deintercalation of lithium to the positive electrode current collector, a polyether modified silicone selected from the group consisting of the compounds of Formulas 1 to 5, and combinations thereof Method of manufacturing a lithium secondary battery comprising the step of immersing or applying oil or a solution containing the same to prepare a positive electrode. [Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

(In Formulas 1 to 5, k has a range of 1 to 9, l has a range of 0 to 3, m has a range of 0 to 1, n has a range of 1 to 2, R is CH ₃ or C ₆ H ₅ Any one of which Z is CH ₃ or C ₂ H ₅ Is either one) The method of claim 14, The polyether-modified silicone oil is a method of manufacturing a lithium secondary battery that is impregnated with an active material capable of intercalation and deintercalation of lithium. The method of claim 15, The polyether-modified silicone oil is a method for producing a lithium secondary battery that is contained in 0.001 to 10% by mass relative to the total mass of the positive electrode active material. The method of claim 16, The polyether-modified silicone oil is a manufacturing method of a lithium secondary battery that is contained in 0.001 to 5% by mass relative to the total mass of the positive electrode active material.

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