WO2019078680A2 - Method for producing negative active material - Google Patents

Method for producing negative active material Download PDF

Info

Publication number
WO2019078680A2
WO2019078680A2 PCT/KR2018/012435 KR2018012435W WO2019078680A2 WO 2019078680 A2 WO2019078680 A2 WO 2019078680A2 KR 2018012435 W KR2018012435 W KR 2018012435W WO 2019078680 A2 WO2019078680 A2 WO 2019078680A2
Authority
WO
WIPO (PCT)
Prior art keywords
sio
active material
reactant
heat treatment
battery
Prior art date
Application number
PCT/KR2018/012435
Other languages
French (fr)
Korean (ko)
Other versions
WO2019078680A3 (en
Inventor
오일근
김은경
이용주
조래환
이수민
최정현
김동혁
박세미
Original Assignee
주식회사 엘지화학
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 주식회사 엘지화학 filed Critical 주식회사 엘지화학
Priority to US16/754,388 priority Critical patent/US11515515B2/en
Priority claimed from KR1020180124981A external-priority patent/KR102290960B1/en
Publication of WO2019078680A2 publication Critical patent/WO2019078680A2/en
Publication of WO2019078680A3 publication Critical patent/WO2019078680A3/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/20—Silicates
    • C01B33/32—Alkali metal silicates

Definitions

  • the present invention relates to a method of manufacturing an anode active material, and more particularly, to a method of manufacturing an anode active material, comprising the steps of: mixing SiO x (0 ⁇ x ⁇ 2) particles containing SiO 2 with Li 2 O to form a mixture; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
  • the secondary battery is composed of an anode, a cathode, an electrolyte, and a separator.
  • a negative electrode comprising a negative electrode active material that insertion and desorption of lithium ions emitted from the positive electrode, as the anode active material may be used as a large SiO x (0 ⁇ x ⁇ 2 ) discharge capacity.
  • SiO x (0 ⁇ x ⁇ 2) reacts with a lithium source in the battery to generate lithium silicate, and the lithium silicate is formed in an irreversible phase, thereby reducing the amount of lithium source contributing to battery charge and discharge. Therefore, there arises a problem that the initial efficiency of the battery is lowered.
  • a problem to be solved by the present invention is to provide a method for manufacturing an anode active material which can prevent the grain size of the silicon from being excessively grown while minimizing the occurrence of irreversible phase caused by a lithium source in the battery.
  • a method of manufacturing a semiconductor device comprising: mixing a SiO x (0 ⁇ x ⁇ 2) particle containing SiO 2 with Li 2 O to form a mixture; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
  • the method of manufacturing an anode active material since lithium silicate is formed in advance through Li 2 O, the occurrence of irreversible phase by the lithium source supplied from the anode can be minimized, Can be improved. Further, at the time of forming the lithium silicate, since the heat treatment temperature is as low as 400 ° C to 600 ° C, the growth of silicon crystal grains in the negative electrode active material can be suppressed, and the lifetime characteristics of the battery can be improved.
  • a method of manufacturing an anode active material according to an embodiment of the present invention includes: forming a mixture by mixing SiO x (0 ⁇ x ⁇ 2) particles containing SiO 2 with Li 2 O; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
  • the SiO x (0 ⁇ x ⁇ 2) particles may include SiO 2 , specifically, Si and SiO 2 . That is, x corresponds to the number ratio of O to Si contained in the SiO x (0 ⁇ x ⁇ 2) particles.
  • the average particle diameter (D 50 ) of the SiO x (0 ⁇ x ⁇ 2) particles may be 3 ⁇ m to 10 ⁇ m, specifically 3 ⁇ m to 7 ⁇ m, and more specifically 3 ⁇ m to 5 ⁇ m .
  • the average particle diameter (D 50 ) can be defined as a particle diameter corresponding to 50% of the number cumulative amount in the particle diameter distribution curve of the particles.
  • the average particle diameter (D 50 ) can be measured using, for example, a laser diffraction method.
  • the laser diffraction method generally enables measurement of a particle diameter of several millimeters from a submicron region, resulting in high reproducibility and high degradability.
  • the Li 2 O reacts with the SiO x (0 ⁇ x ⁇ 2) particles to form lithium silicate.
  • the lithium in the battery for example, lithium supplied from the anode to react with oxygen in the SiO x (0 ⁇ x ⁇ 2) particles to form an irreversible phase.
  • the initial efficiency of the battery can be improved.
  • the average particle diameter (D 50 ) of the Li 2 O may be 1 ⁇ to 10 ⁇ , specifically 1 ⁇ to 5 ⁇ , and more specifically, 1 ⁇ to 3 ⁇ .
  • D 50 The average particle diameter of the Li 2 O
  • the SiO x (0 ⁇ x ⁇ 2) particles and the Li 2 O may be mixed in a weight ratio of 1: 0.1 to 1: 0.666. Specifically, the weight ratio is 1: 1: 0.334.
  • Li ions can be sufficiently supplied from the Li 2 O, and lithium silicate such as Li 4 SiO 4 can be formed smoothly.
  • the mixing may be carried out by a conventional method.
  • the mixing may be carried out by at least one method selected from the group consisting of ball mill, stirring, induction mixing, and the like.
  • the heat treatment temperature of the mixture may be 400 ° C to 600 ° C, specifically, 500 ° C to 600 ° C.
  • the heat treatment temperature is required to be 900 ° C. or higher.
  • silicon crystal grains in SiO x (0 ⁇ x ⁇ 2) grains excessively grow, which causes a problem of deteriorating the life characteristics of the battery.
  • the heat treatment temperature for lithium silicate formation may be a relatively low temperature.
  • SiO x (0 ⁇ x ⁇ 2) grains it is possible to prevent excessive growth of silicon grains in the SiO x (0 ⁇ x ⁇ 2) grains, so that the lifetime characteristics of the battery can be improved.
  • the heat treatment time may be 3 hours or more, specifically 3 hours to 5 hours. Since the negative electrode active material having a heat treatment time of more than 5 hours is not significantly different from the negative electrode active material produced by the heat treatment for 3 hours to 5 hours, considering the process efficiency, 3 hours to 5 hours correspond to the most preferable time do.
  • lithium silicate may be formed in the SiO x (0 ⁇ x ⁇ 2) particles by the heat treatment.
  • the lithium silicate may be formed by reacting SiO 2 and Li 2 O existing on the surface and / or inside the SiO x (0 ⁇ x ⁇ 2) particle during the heat treatment.
  • the lithium silicate can minimize the phenomenon that lithium supplied from a lithium source in the cell, for example, lithium supplied from an anode, reacts with the SiO x (0 ⁇ x ⁇ 2) particles to form an irreversible phase.
  • the initial efficiency of the battery can be improved.
  • the lithium silicate may include Li 4 SiO 4 , Li 2 SiO 3 , Li 2 Si 2 O 5 , and the like.
  • the Li 4 SiO 4 corresponds to lithium silicate which is mainly generated in the heat treatment temperature range of the present invention.
  • the reactant formed by the heat treatment may include Li 4 SiO 4 .
  • the Li 4 SiO 4 may be 40 wt% to 60 wt%, and more preferably 40 wt% to 55 wt%, of the total weight of the reactants.
  • the capacity decrease of the battery is minimized, and at the same time, SiO x (0 ⁇ x ⁇ 2) particles are smoothly reduced and the initial efficiency can be improved.
  • the reactant formed by the heat treatment may include at least one of Li 2 SiO 3 and Li 2 Si 2 O 5 .
  • the total content of Li 2 SiO 3 and Li 2 Si 2 O 5 may be 0.3 wt% to 4 wt% based on the total weight of the reactants formed by the heat treatment, specifically 0.5 wt% to 3 wt% have.
  • the initial efficiency can be improved at the same time as the capacity drop of the battery is minimized.
  • the washing may be performed using water.
  • the lithium silicate to be removed may include Li 4 SiO 4 .
  • Li 4 SiO 4 formed in the process of the present invention is lithium silicate which can be easily washed with water. Therefore, Li 4 SiO 4 can be easily removed from the reactants by using water even if there is no acid such as HCl. Thus, the manufacturing process of the negative electrode active material can be simplified.
  • Li 2 SiO 3 and Li 2 Si 2 O 5 are not water-soluble lithium silicate, they are not removed by washing with water, but remain in the negative electrode active material.
  • the initial efficiency of the battery can be improved by the appropriate amounts of Li 2 SiO 3 and Li 2 Si 2 O 5 .
  • the negative electrode active material according to another embodiment of the present invention is the negative electrode active material prepared by the above-described method of manufacturing the negative electrode active material.
  • the negative electrode according to another embodiment of the present invention may include a current collector and a negative electrode active material layer disposed on the current collector.
  • the negative electrode active material layer may include the negative electrode active material.
  • the negative electrode active material layer may further include a binder and / or a conductive material.
  • the current collector is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery.
  • the current collector may be made of copper, stainless steel, aluminum, nickel, titanium, sintered carbon, or a surface of aluminum or stainless steel surface treated with carbon, nickel, titanium or silver.
  • a transition metal that adsorbs carbon well such as copper or nickel can be used as a current collector.
  • the current collector may have a thickness of 6 to 20 ⁇ , but the thickness of the current collector is not limited thereto.
  • the binder may be selected from the group consisting of polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride, polyacrylonitrile, polymethylmethacrylate, poly Polypropylene, polyacrylic acid, ethylene-propylene-diene monomer (EPDM), liquor, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, And may include at least any one selected from the group consisting of polyvinylidene fluoride (EPDM), styrene butadiene rubber (SBR), fluorine rubber, poly acrylic acid, and materials in which hydrogen thereof is substituted with Li, Na, Ca, And may include various copolymers thereof.
  • PVDF-co-HFP polyvinylidene fluoride-hexafluoropropylene cop
  • the conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, and examples thereof include graphite such as natural graphite and artificial graphite; Carbon black such as carbon black, acetylene black, Ketjen black, channel black, panes black, lamp black, and thermal black; Conductive fibers such as carbon fiber and metal fiber; Conductive tubes such as carbon nanotubes; Metal powders such as fluorocarbon, 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.
  • graphite such as natural graphite and artificial graphite
  • Carbon black such as carbon black, acetylene black, Ketjen black, channel black, panes black, lamp black, and thermal black
  • Conductive fibers such as carbon fiber and metal fiber
  • Conductive tubes such as carbon nanotubes
  • Metal powders such as fluorocarbon, aluminum and nickel powder
  • the secondary battery according to another embodiment of the present invention may include a cathode, an anode, a separator interposed between the anode and the cathode, and an electrolyte, and the cathode is the same as the cathode described above. Since the negative electrode has been described above, a detailed description thereof will be omitted.
  • the positive electrode may include a positive electrode collector and a positive electrode active material layer formed on the positive electrode collector and including the positive electrode active material.
  • the cathode current collector is not particularly limited as long as it has conductivity without causing a chemical change in the battery, and for example, a metal such as stainless steel, aluminum, nickel, titanium, sintered carbon, , Nickel, titanium, silver, or the like may be used.
  • the cathode current collector may have a thickness of 3 to 500 ⁇ , and fine unevenness may be formed on the surface of the current collector to increase the adhesive force of the cathode active material.
  • it can be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric.
  • the cathode active material may be a commonly used cathode active material.
  • the cathode active material may be a layered compound such as lithium cobalt oxide (LiCoO 2 ) or lithium nickel oxide (LiNiO 2 ) or a compound substituted with one or more transition metals; Lithium iron oxides such as LiFe 3 O 4 ; Formula Li 1 + c1 Mn 2-c1 O 4 (0 ⁇ c1 ⁇ 0.33), LiMnO 3, the lithium manganese oxide such as LiMn 2 O 3, LiMnO 2; Lithium copper oxide (Li 2 CuO 2 ); Vanadium oxides such as LiV 3 O 8 , V 2 O 5 and Cu 2 V 2 O 7 ; Formula LiNi 1-c2 M c2 O 2 expressed as (where, M is at least one, satisfies 0.01 ⁇ c2 ⁇ 0.3 selected from the group consisting of Co, Mn, Al, Cu, Fe, Mg, B and Ga) ≪ / RTI &
  • the positive electrode active material layer may include a positive electrode conductive material and a positive electrode binder together with the above-described positive electrode active material.
  • the positive electrode conductive material is used for imparting conductivity to the electrode, and the positive electrode conductive material can be used without particular limitation as long as it has electron conductivity without causing chemical change.
  • Specific examples thereof include graphite such as natural graphite and artificial graphite; Carbon-based materials such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, summer black and carbon fiber; Metal powder or metal fibers such as copper, nickel, aluminum and silver; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; And polyphenylene derivatives. These may be used alone or in admixture of two or more.
  • the positive electrode binder improves adhesion between the positive electrode active material particles and adhesion between the positive electrode active material and the positive electrode collector.
  • Specific examples include polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethylcellulose ), Starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated-EPDM, styrene butadiene rubber (SBR), fluororubber, and various copolymers thereof.
  • PVDF polyvinylidene fluoride
  • PVDF-co-HFP vinylidene fluoride-hexafluoropropylene copolymer
  • PVDF-co-HFP polyvinyl
  • the separator separates the cathode and the anode and provides a passage for lithium ion.
  • the separator can be used without any particular limitation as long as it is used as a separator in a secondary battery.
  • the separator can be used with low resistance against electrolyte migration, .
  • porous polymer films such as porous polymer films made of polyolefin-based polymers such as ethylene homopolymers, propylene homopolymers, ethylene / butene copolymers, ethylene / hexene copolymers and ethylene / methacrylate copolymers, May be used.
  • a nonwoven fabric made of a conventional porous nonwoven fabric for example, glass fiber of high melting point, polyethylene terephthalate fiber, or the like may be used.
  • a coated separator containing a ceramic component or a polymer material may be used, and the separator may be selectively used as a single layer or a multilayer structure.
  • Examples of the electrolyte include an organic liquid electrolyte, an inorganic liquid electrolyte, a solid polymer electrolyte, a gel polymer electrolyte, a solid inorganic electrolyte, and a molten inorganic electrolyte that can be used in the production of a lithium secondary battery, but are not limited thereto.
  • the electrolyte may include a non-aqueous organic solvent and a metal salt.
  • non-aqueous organic solvent examples include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma-butylolactone, Tetrahydrofuran, tetrahydrofuran, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate
  • organic solvent examples include methyl acetate, phosphoric acid triester, trimethoxy methane, dioxolane derivatives, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, Propylenic organic solvents such as methylmethyl, ethylpropionate and
  • ethylene carbonate and propylene carbonate which are cyclic carbonates in the carbonate-based organic solvent, can be preferably used because they have high permittivity as a high viscosity organic solvent and dissociate the lithium salt well.
  • dimethyl carbonate and diethyl carbonate When the same low viscosity and low dielectric constant linear carbonate are mixed in an appropriate ratio, an electrolyte having a high electric conductivity can be prepared, and thus it can be used more preferably.
  • the metal salt may be a lithium salt, and the lithium salt may be soluble in the non-aqueous electrolyte.
  • the anion of the lithium salt include F - , Cl - , I - , NO 3 - , N ) 2 -, BF 4 -, ClO 4 -, PF 6 -, (CF 3) 2 PF 4 -, (CF 3) 3 PF 3 -, (CF 3) 4 PF 2 -, (CF 3) 5 PF - , (CF 3) 6 P - , CF 3 SO 3 -, CF 3 CF 2 SO 3 -, (CF 3 SO 2) 2 N -, (FSO 2) 2 N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2 ) 2 CH -, (SF 5) 3 C -, (CF 3 SO 2) 3 C -, CF 3 (CF 2) 7 SO 3 -, CF 3 CO 2 -, CH 3 At least one selected from the group consist
  • the electrolyte may contain, for example, a haloalkylene carbonate-based compound such as difluoroethylene carbonate or the like, pyridine, triethanolamine, or the like for the purpose of improving lifetime characteristics of the battery, Ethyl phosphite, triethanol amine, cyclic ether, ethylenediamine, glyme, hexametriamide, nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, At least one additive such as benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol
  • a battery module including the secondary battery as a unit cell and a battery pack including the same. Since the battery module and the battery pack include the secondary battery having a high capacity, high speed-rate characteristics, and a cycling characteristic, the battery module and the battery pack can be suitably used as a middle- or large-sized device selected from the group consisting of electric vehicles, hybrid electric vehicles, plug- As shown in FIG.
  • Example 1 The reaction was poured into water and stirred (washed) for 30 minutes to partially remove lithium silicate in the reaction.
  • the negative electrode active material of Example 1 was prepared. Table 1 shows the sizes of the silicon crystal grains in the prepared negative electrode active material.
  • Carbon methylmethyl cellulose (CMC) and styrene butadiene rubber (SBR) were mixed in a weight ratio of 4.8: 91: 1: 1.7: 1.5 to prepare a negative electrode active material, graphite, carbon black as a conductive material, 5 g of a mixture was prepared. 28.9 g of distilled water was added to the mixture to prepare an anode slurry.
  • the negative electrode slurry was applied to a copper (Cu) metal thin film as an anode current collector having a thickness of 20 ⁇ and dried. The temperature of the circulated air was 60 ° C. Subsequently, this was rolled, dried in a vacuum oven at 130 DEG C for 12 hours, and then drum-shaped in a circular shape of 1.4875 cm < 2 > to produce a negative electrode.
  • Cu copper
  • the prepared negative electrode was cut into a circle of 1.7671 cm < 2 > and a lithium metal thin film was used as the positive electrode.
  • 0.5% by weight of vinylene carbonate dissolved in a mixed solution of methyl ethyl carbonate (EMC) and ethylene carbonate (EC) at a mixing volume ratio of 7: 3 was placed between the anode and the cathode through a separator of porous polyethylene, And an electrolytic solution in which 1 M LiPF 6 was dissolved was injected to prepare a lithium coin half-cell.
  • EMC methyl ethyl carbonate
  • EC ethylene carbonate
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 450 ⁇ in the heat treatment process of Example 1.
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the heat treatment time was changed to 5 hours in the heat treatment step of Example 1.
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the heat treatment time in Example 1 was changed to 6 hours.
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 900 ° C. in the heat treatment step of Example 1.
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 300 ⁇ in the heat treatment step of Example 1.
  • a negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reaction furnace was changed to 650 ° C in the heat treatment step of Example 1.
  • a negative electrode and a secondary battery were produced in the same manner as in Example 1.
  • Example 1 Li 4 SiO 4 content (wt%) Li 2 SiO 3 content (wt%) Li 2 Si 2 O 5 content (wt%) Silicon grain size (nm)
  • Example 1 48.7 0.8 2.0 0
  • Example 2 42.1 0.3 0.5 0
  • Example 3 48.6 0.8 2.0 0
  • Example 4 48.7 0.8 1.9 0
  • Comparative Example 1 30.7 14.0 22.3 11.3
  • Comparative Example 2 23.1 0.4 0.8 0 Comparative Example 3 40.6 2.5 3.1 6.6 Comparative Example 4 7.3 3.2 3.2 0 Comparative Example 5 25.8 11.4 11.4 11.1
  • the lithium silicate The content was based on the total weight of the reactants after the heat treatment and before washing, and was measured by XRD quantitative analysis.
  • the size of silicon grains was measured by the XRD scherrer equation.
  • Test Example 1 Evaluation of Discharge Capacity, Initial Efficiency, Capacity Retention Rate
  • the first cycle and the second cycle were charged and discharged at 0.1 C, and charge and discharge were performed at 0.5 C from the third cycle to the 49th cycle.
  • the 50 cycles were terminated in the state of charge (state in which lithium was contained in the cathode).
  • the discharge capacity (mAh / g) and the initial efficiency (%) were derived from the results of one charge / discharge cycle. Specifically, the initial efficiency (%) was derived by the following calculation.
  • the capacity retention rate and the electrode thickness change ratio were derived by the following calculation, respectively.
  • Capacity retention rate (%) (49 times discharge capacity / one time discharge capacity) x 100
  • Example 1 405.5 89.9 73.2
  • Example 2 405.2 89.6 72.9
  • Example 3 405.5 89.8 73.1
  • Example 4 405.4 89.9 73.2 Comparative Example 1 398.1 89.5 68.9 Comparative Example 2 401.6 86.0 70.1 Comparative Example 3 404.0 89.6 69.5 Comparative Example 4 400.8 86.2 70.3 Comparative Example 5 405.3 89.6 67.1
  • Comparative Example 3 where Li 2 O was used and a high temperature of 650 ⁇ was used, the silicon crystal grains were excessively grown and the capacity retention rate was low. In addition, it was confirmed that Li 2 SiO 3 and Li 2 Si 2 O 5 exist in an excessively large content, and the capacity characteristics of the battery are poor.
  • Comparative Example 2 using Li 2 O and Comparative Example 2 using Li at a low temperature and Comparative Example 3 using Li at a low temperature of 550 ° C did not find silicon grains but a small amount of Li 4 SiO 4 It can be seen that the reduction of SiO was not performed smoothly at the formed point. Thus, the effect of improving the initial efficiency, the discharge capacity, and the capacity retention rate is insufficient.
  • Comparative Example 5 in which Li was used and subjected to a heat treatment at a high temperature of 900 ⁇ , a large amount of lithium silicate was formed to increase the initial efficiency, but the crystal grains were excessively grown and the capacity retention rate was low.
  • Example 1 Compared Example 1 with Example 2, it can be seen that the discharge capacity, initial efficiency, and capacity retention rate of Example 1 heat-treated at 550 ° C are superior to those of Example 2 that was heat-treated at 450 ° C. Comparing Example 1, Example 3 and Example 4, it was confirmed that Example 4 in which the heat treatment time exceeded 5 hours was equivalent to Example 1 in which heat treatment for 3 hours was performed and Example 3 for heat treatment for 5 hours . Therefore, it is most preferable to conduct the heat treatment for 3 hours to 5 hours for the process efficiency.

Abstract

The present invention relates to a method for producing a negative active material, comprising the steps of: forming a mixture by mixing Li2O with SiOx (0<x<2) particles comprising SiO2; forming a reactant by heat-treating the mixture at 400°C to 600°C; and removing some of the lithium silicates in the reactant by cleaning the reactant.

Description

음극 활물질의 제조방법Method for manufacturing negative electrode active material
관련출원과의 상호인용Mutual citation with related application
본 출원은 2017년 10월 19일자 출원된 한국 특허 출원 제10-2017-0135616호 및 2018년 10월 19일자 출원된 한국 특허 출원 제10-2018-0124981호에 기초한 우선권의 이익을 주장하며, 해당 한국 특허 출원의 문헌에 개시된 모든 내용은 본 명세서의 일부로서 포함된다.This application claims the benefit of priority based on Korean Patent Application No. 10-2017-0135616, filed on October 19, 2017, and Korean Patent Application No. 10-2018-0124981, filed on October 19, 2018, All the contents disclosed in the Korean patent application are incorporated herein by reference.
기술분야Technical field
본 발명은 음극 활물질의 제조 방법에 관한 것으로, 구체적으로 상기 음극 활물질의 제조 방법은 SiO2를 포함하는 SiOx(0<x<2) 입자와 Li2O를 혼합하여 혼합물을 형성하는 단계; 상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계; 및 상기 반응물을 세척하여 상기 반응물 내 리튬 실리케이트를 일부 제거하는 단계;를 포함할 수 있다.The present invention relates to a method of manufacturing an anode active material, and more particularly, to a method of manufacturing an anode active material, comprising the steps of: mixing SiO x (0 <x <2) particles containing SiO 2 with Li 2 O to form a mixture; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
화석연료 사용의 급격한 증가로 인하여 대체 에너지나 청정에너지의 사용에 대한 요구가 증가하고 있으며, 그 일환으로 가장 활발하게 연구되고 있는 분야가 전기화학 반응을 이용한 발전, 축전 분야이다.Due to the rapid increase in the use of fossil fuels, the demand for the use of alternative energy or clean energy is increasing. As a part of this, the most active field of research is electric power generation and storage.
현재 이러한 전기화학적 에너지를 이용하는 전기화학 소자의 대표적인 예로 이차 전지를 들 수 있으며, 점점 더 그 사용 영역이 확대되고 있는 추세이다. 최근에는 휴대용 컴퓨터, 휴대용 전화기, 카메라 등의 휴대용 기기에 대한 기술 개발과 수요가 증가함에 따라 에너지원으로서 이차전지의 수요가 급격히 증가하고 있고, 그러한 이차 전지 중 높은 에너지 밀도, 즉 고용량의 리튬 이차전지에 대해 많은 연구가 행해져 왔고, 또한 상용화되어 널리 사용되고 있다.At present, a typical example of an electrochemical device utilizing such electrochemical energy is a secondary battery, and the use area thereof is gradually increasing. 2. Description of the Related Art [0002] Recently, as technology development and demand for portable devices such as portable computers, portable phones, cameras, and the like have increased, the demand for secondary batteries as energy sources has been rapidly increasing. Among such secondary batteries, high energy density, Have been studied, and they have been commercialized and widely used.
일반적으로 이차 전지는 양극, 음극, 전해질, 및 분리막으로 구성된다. 음극은 양극으로부터 나온 리튬 이온을 삽입하고 탈리시키는 음극 활물질을 포함하며, 상기 음극 활물질로는 방전 용량이 큰 SiOx(0<x<2)가 사용될 수 있다. 다만, SiOx(0<x<2)는 전지 내 리튬 소스와 반응하여 리튬 실리케이트를 발생시키며, 상기 리튬 실리케이트는 비가역상으로 형성되어, 전지 충방전에 기여하는 리튬 소스의 양이 줄어들게 된다. 따라서, 전지 초기 효율이 저하되는 문제가 발생한다. Generally, the secondary battery is composed of an anode, a cathode, an electrolyte, and a separator. A negative electrode comprising a negative electrode active material that insertion and desorption of lithium ions emitted from the positive electrode, as the anode active material may be used as a large SiO x (0 <x <2 ) discharge capacity. However, SiO x (0 < x < 2) reacts with a lithium source in the battery to generate lithium silicate, and the lithium silicate is formed in an irreversible phase, thereby reducing the amount of lithium source contributing to battery charge and discharge. Therefore, there arises a problem that the initial efficiency of the battery is lowered.
이에, 종래에는 SiOx(0≤x<2)를 리튬 금속과 혼합하여 열처리시켜서 리튬 실리케이트는 미리 형성시키는 기술을 사용해왔다. 이 경우, 비가역상으로 전환되는 전지 내 리튬 소스의 양이 최소화될 수 있어서, 전지의 초기 효율이 개선될 수 있다. Thus, conventionally, a technique of preliminarily forming lithium silicate by mixing SiO x (0? X <2) with lithium metal and heat-treating has been used. In this case, the amount of the lithium source in the battery which is converted into the non-reversed phase can be minimized, so that the initial efficiency of the battery can be improved.
그러나, 리튬 금속과 SiOx(0≤x<2)을 반응시키기 위해서는 일반적으로 900℃이상의 고온에서의 열처리가 필요하며, 이러한 고온에서는 SiOx(0≤x<2) 내 실리콘의 결정립 크기가 과도하게 커지게 된다. 실리콘의 결정립 크기가 과도하게 커짐에 따라, 전지의 사이클 특성이 저하되는 문제가 발생한다.However, in order to react lithium metal with SiO x (0? X <2), heat treatment at a high temperature of 900 ° C. or more is generally required, and at such a high temperature, the grain size of silicon in SiO x (0≤x <2) . As the crystal grain size of silicon becomes excessively large, there arises a problem that the cycle characteristics of the battery are deteriorated.
따라서, 전지 내 리튬 소스에 의한 비가역상 발생을 최소화하면서, 실리콘의 결정립 크기가 과도하게 성장하는 것을 방지할 수 있는 음극 활물질의 제조 방법이 요구되고 있다.Therefore, there is a demand for a method of manufacturing an anode active material that can prevent the crystal grain size from being excessively grown while minimizing the occurrence of non-reversible phase caused by the lithium source in the battery.
본 발명이 해결하고자 하는 일 과제는 전지 내 리튬 소스에 의한 비가역상 발생을 최소화하면서, 실리콘의 결정립 크기가 과도하게 성장하는 것을 방지할 수 있는 음극 활물질의 제조 방법을 제공하는 것이다.A problem to be solved by the present invention is to provide a method for manufacturing an anode active material which can prevent the grain size of the silicon from being excessively grown while minimizing the occurrence of irreversible phase caused by a lithium source in the battery.
본 발명의 일 실시예에 따르면, SiO2를 포함하는 SiOx(0<x<2) 입자와 Li2O를 혼합하여 혼합물을 형성하는 단계; 상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계; 및 상기 반응물을 세척하여 상기 반응물 내 리튬 실리케이트를 일부 제거하는 단계;를 포함하는 음극 활물질 제조 방법이 제공된다.According to an embodiment of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: mixing a SiO x (0 < x < 2) particle containing SiO 2 with Li 2 O to form a mixture; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
본 발명의 일 실시예에 따른 음극 활물질의 제조 방법에 따르면, Li2O를 통해 리튬 실리케이트를 미리 형성시켜, 양극에서 공급되는 리튬 소스에 의한 비가역상 발생을 최소화할 수 있으므로, 전지의 초기 효율이 개선될 수 있다. 또한, 상기 리튬 실리케이트 형성 시, 열처리 온도가 400℃ 내지 600℃로 낮기 때문에, 음극 활물질 내 실리콘 결정립의 성장을 억제할 수 있어서, 전지의 수명 특성이 개선될 수 있다.According to the method of manufacturing an anode active material according to an embodiment of the present invention, since lithium silicate is formed in advance through Li 2 O, the occurrence of irreversible phase by the lithium source supplied from the anode can be minimized, Can be improved. Further, at the time of forming the lithium silicate, since the heat treatment temperature is as low as 400 ° C to 600 ° C, the growth of silicon crystal grains in the negative electrode active material can be suppressed, and the lifetime characteristics of the battery can be improved.
이하, 본 발명에 대한 이해를 돕기 위해 본 발명을 더욱 상세하게 설명한다. Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.
본 명세서 및 청구범위에 사용된 용어나 단어는 통상적이거나 사전적인 의미로 한정해서 해석되어서는 아니되며, 발명자는 그 자신의 발명을 가장 최선의 방법으로 설명하기 위해 용어의 개념을 적절하게 정의할 수 있다는 원칙에 입각하여 본 발명의 기술적 사상에 부합하는 의미와 개념으로 해석되어야만 한다.The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.
본 명세서에서 사용되는 용어는 단지 예시적인 실시예들을 설명하기 위해 사용된 것으로, 본 발명을 한정하려는 의도는 아니다. 단수의 표현은 문맥상 명백하게 다르게 뜻하지 않는 한, 복수의 표현을 포함한다. The terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.
본 명세서에서, "포함하다", "구비하다" 또는 "가지다" 등의 용어는 실시된 특징, 숫자, 단계, 구성 요소 또는 이들을 조합한 것이 존재함을 지정하려는 것이지, 하나 또는 그 이상의 다른 특징들이나 숫자, 단계, 구성 요소, 또는 이들을 조합한 것들의 존재 또는 부가 가능성을 미리 배제하지 않는 것으로 이해되어야 한다.In this specification, the terms " comprising, " " comprising, " or " having ", and the like are intended to specify the presence of stated features, But do not preclude the presence or addition of one or more other features, integers, steps, components, or combinations thereof.
본 발명의 일 실시예에 따른 음극 활물질의 제조 방법은 SiO2를 포함하는 SiOx(0<x<2) 입자와 Li2O를 혼합하여 혼합물을 형성하는 단계; 상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계; 및 상기 반응물을 세척하여 상기 반응물 내 리튬 실리케이트를 일부 제거하는 단계;를 포함할 수 있다.A method of manufacturing an anode active material according to an embodiment of the present invention includes: forming a mixture by mixing SiO x (0 <x <2) particles containing SiO 2 with Li 2 O; Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And washing the reactant to partially remove lithium silicate in the reactant.
상기 혼합물을 형성하는 단계에 있어서, 상기 SiOx(0<x<2) 입자는 SiO2를 포함할 수 있으며, 구체적으로 Si 및 SiO2이 포함된 형태일 수 있다. 즉, 상기 x는 상기 SiOx(0<x<2) 입자 내에 포함된 Si에 대한 O의 개수비에 해당한다. In the step of forming the mixture, the SiO x (0 < x < 2) particles may include SiO 2 , specifically, Si and SiO 2 . That is, x corresponds to the number ratio of O to Si contained in the SiO x (0 <x <2) particles.
상기 SiOx(0<x<2) 입자의 평균 입경(D50)은 3㎛ 내지 10㎛일 수 있으며, 구체적으로 3㎛ 내지 7㎛일 수 있고, 더욱 구체적으로 3㎛ 내지 5㎛일 수 있다. 상기 범위를 만족하는 경우, Li2O와의 반응성이 향상되어 반응 효율이 증가될 수 있다. 본 명세서에서 평균 입경(D50)은 입자의 입경 분포 곡선에 있어서, 개수 누적량의 50%에 해당하는 입경으로 정의할 수 있다. 상기 평균 입경(D50)은 예를 들어, 레이저 회절법(laser diffraction method)을 이용하여 측정할 수 있다. 상기 레이저 회절법은 일반적으로 서브미크론(submicron) 영역에서부터 수 mm 정도의 입경의 측정이 가능하며, 고 재현성 및 고 분해성의 결과를 얻을 수 있다.The average particle diameter (D 50 ) of the SiO x (0 <x <2) particles may be 3 μm to 10 μm, specifically 3 μm to 7 μm, and more specifically 3 μm to 5 μm . When the above range is satisfied, the reactivity with Li 2 O is improved and the reaction efficiency can be increased. In the present specification, the average particle diameter (D 50 ) can be defined as a particle diameter corresponding to 50% of the number cumulative amount in the particle diameter distribution curve of the particles. The average particle diameter (D 50 ) can be measured using, for example, a laser diffraction method. The laser diffraction method generally enables measurement of a particle diameter of several millimeters from a submicron region, resulting in high reproducibility and high degradability.
상기 혼합물을 형성하는 단계에 있어서, 상기 Li2O는 상기 SiOx(0<x<2) 입자와 반응하여 리튬 실리케이트를 형성시키는 역할을 한다. 이에 따라, 전지 내 리튬 소스, 예컨대 양극으로부터 공급된 리튬이 상기 SiOx(0<x<2) 입자 내 산소와 반응하여 비가역상을 형성하는 것을 최소화할 수 있다. 이에 따라, 전지의 초기 효율이 개선될 수 있다. In the forming the mixture, the Li 2 O reacts with the SiO x (0 <x <2) particles to form lithium silicate. Thus, it is possible to minimize the lithium in the battery, for example, lithium supplied from the anode to react with oxygen in the SiO x (0 < x < 2) particles to form an irreversible phase. Thus, the initial efficiency of the battery can be improved.
상기 Li2O의 평균 입경(D50)은 1㎛ 내지 10㎛일 수 있으며, 구체적으로 1㎛ 내지 5㎛일 수 있고, 더욱 구체적으로 1㎛ 내지 3㎛일 수 있다. 상기 범위를 만족하는 경우, 상기 SiOx(0<x<2) 입자의 반응성이 향상될 수 있다.The average particle diameter (D 50 ) of the Li 2 O may be 1 탆 to 10 탆, specifically 1 탆 to 5 탆, and more specifically, 1 탆 to 3 탆. When the above range is satisfied, the reactivity of the SiO x (0 <x <2) particles can be improved.
상기 혼합물을 형성하는 단계에 있어서, 상기 SiOx(0<x<2) 입자와 상기 Li2O는 1:0.1 내지 1:0.666의 중량비로 혼합될 수 있으며, 구체적으로 상기 중량비는 1:0.25 내지 1:0.334일 수 있다. 상기 중량비를 만족하는 경우, 상기 Li2O 으로부터 Li 이온이 충분히 공급될 수 있어서, Li4SiO4 등의 리튬 실리케이트가 원활하게 형성될 수 있다.In the step of forming the mixture, the SiO x (0 <x <2) particles and the Li 2 O may be mixed in a weight ratio of 1: 0.1 to 1: 0.666. Specifically, the weight ratio is 1: 1: 0.334. When the weight ratio is satisfied, Li ions can be sufficiently supplied from the Li 2 O, and lithium silicate such as Li 4 SiO 4 can be formed smoothly.
상기 혼합물을 형성하는 단계에 있어서, 상기 혼합은 통상의 방법을 통해 혼합될 수 있다. 예를 들어, 상기 혼합은 볼 밀, 교반, 유발 혼합 등의 방법에서 선택되는 적어도 어느 하나의 방법에 의해 진행될 수 있다.In the step of forming the mixture, the mixing may be carried out by a conventional method. For example, the mixing may be carried out by at least one method selected from the group consisting of ball mill, stirring, induction mixing, and the like.
상기 반응물을 형성하는 단계에 있어서, 상기 혼합물의 열처리 온도는 400℃ 내지 600℃일 수 있으며, 구체적으로 500℃ 내지 600℃일 수 있다. Li2O가 아닌 리튬 금속을 SiOx(0<x<2) 입자와 반응시켜 리튬 실리케이트를 형성시키는 방법의 경우, 열처리 온도는 900℃이상일 것이 요구된다. 그러나, 900℃이상의 온도에서는 SiOx(0<x<2) 입자 내의 실리콘 결정립이 과도하게 성장하게 되어, 전지의 수명 특성을 저하시키는 문제가 발생한다. 이와 달리, 본 발명에서는 리튬 금속이 아닌 Li2O를 SiOx(0<x<2) 입자와 반응시키므로, 리튬 실리케이트 형성을 위한 열처리 온도가 비교적 낮은 온도일 수 있다. 이에 따라, SiOx(0<x<2) 입자 내의 실리콘 결정립이 과도하게 성장하는 것을 방지할 수 있으므로, 전지의 수명 특성이 개선될 수 있다.In the step of forming the reactant, the heat treatment temperature of the mixture may be 400 ° C to 600 ° C, specifically, 500 ° C to 600 ° C. In the case of a method in which lithium metal other than Li 2 O is reacted with SiO x (0 <x <2) particles to form lithium silicate, the heat treatment temperature is required to be 900 ° C. or higher. However, at a temperature of 900 占 폚 or higher, silicon crystal grains in SiO x (0 <x <2) grains excessively grow, which causes a problem of deteriorating the life characteristics of the battery. Alternatively, in the present invention, since Li 2 O, which is not a lithium metal, is reacted with SiO x (0 <x <2) particles, the heat treatment temperature for lithium silicate formation may be a relatively low temperature. Thus, it is possible to prevent excessive growth of silicon grains in the SiO x (0 < x < 2) grains, so that the lifetime characteristics of the battery can be improved.
상기 열처리 시간은 3시간 이상일 수 있으며, 구체적으로 3시간 내지 5시간일 수 있다. 열처리 시간이 5시간을 초과하여 제조된 음극 활물질은, 3시간 내지 5시간 열처리 하여 제조된 음극 활물질과 물성적인 측면에서 크게 다르지 않으므로, 공정 효율성을 생각할 때 3시간 내지 5시간이 가장 바람직한 시간에 해당한다.The heat treatment time may be 3 hours or more, specifically 3 hours to 5 hours. Since the negative electrode active material having a heat treatment time of more than 5 hours is not significantly different from the negative electrode active material produced by the heat treatment for 3 hours to 5 hours, considering the process efficiency, 3 hours to 5 hours correspond to the most preferable time do.
상기 반응물을 형성하는 단계에 있어서, 상기 열처리에 의해 SiOx(0<x<2) 입자 내에 리튬 실리케이트가 형성될 수 있다. 구체적으로, 상기 리튬 실리케이트는 상기 열처리 시, SiOx(0<x<2) 입자 표면 및/또는 내부에 존재하는 SiO2와 Li2O가 반응하여 형성된 것일 수 있다. 상기 리튬 실리케이트에 의해 전지 내 리튬 소스, 예컨대 양극으로부터 공급된 리튬이 상기 SiOx(0<x<2) 입자와 반응하여 비가역상을 형성되는 현상이 최소화될 수 있다. 이에 따라, 전지의 초기 효율이 개선될 수 있다. In the step of forming the reactant, lithium silicate may be formed in the SiO x (0 <x <2) particles by the heat treatment. Specifically, the lithium silicate may be formed by reacting SiO 2 and Li 2 O existing on the surface and / or inside the SiO x (0 <x <2) particle during the heat treatment. The lithium silicate can minimize the phenomenon that lithium supplied from a lithium source in the cell, for example, lithium supplied from an anode, reacts with the SiO x (0 <x <2) particles to form an irreversible phase. Thus, the initial efficiency of the battery can be improved.
상기 리튬 실리케이트는 Li4SiO4, Li2SiO3, Li2Si2O5 등을 포함할 수 있다. 상기 Li4SiO4는 본 발명의 열처리 온도 범위로 열처리하는 경우에 주로 발생되는 리튬 실리케이트에 해당한다. The lithium silicate may include Li 4 SiO 4 , Li 2 SiO 3 , Li 2 Si 2 O 5 , and the like. The Li 4 SiO 4 corresponds to lithium silicate which is mainly generated in the heat treatment temperature range of the present invention.
보다 구체적으로, 상기 열처리하여 형성된 반응물은 Li4SiO4를 포함할 수 있다. 상기 Li4SiO4은 상기 반응물 전체 중량 중 40중량% 내지 60중량%일 수 있으며, 구체적으로 40중량% 내지 55중량%일 수 있다. 상기 범위를 만족하는 경우, 전지의 용량 저하가 최소화되면서, 동시에 SiOx(0<x<2) 입자가 원활하게 환원되어 초기 효율이 개선될 수 있다.More specifically, the reactant formed by the heat treatment may include Li 4 SiO 4 . The Li 4 SiO 4 may be 40 wt% to 60 wt%, and more preferably 40 wt% to 55 wt%, of the total weight of the reactants. When the above range is satisfied, the capacity decrease of the battery is minimized, and at the same time, SiO x (0 <x <2) particles are smoothly reduced and the initial efficiency can be improved.
상기 열처리하여 형성된 반응물은 Li2SiO3 및 Li2Si2O5 중 적어도 어느 하나를 포함할 수 있다. 상기 상기 Li2SiO3 및 상기 Li2Si2O5의 총 함량은 상기 열처리하여 형성된 반응물 전체 중량을 기준으로 0.3중량% 내지 4중량%일 수 있으며, 구체적으로 0.5중량% 내지 3중량%일 수 있다. 상기 범위를 만족하는 경우, 전지의 용량 저하가 최소화되면서, 동시에 초기 효율이 개선될 수 있다.The reactant formed by the heat treatment may include at least one of Li 2 SiO 3 and Li 2 Si 2 O 5 . The total content of Li 2 SiO 3 and Li 2 Si 2 O 5 may be 0.3 wt% to 4 wt% based on the total weight of the reactants formed by the heat treatment, specifically 0.5 wt% to 3 wt% have. When the above range is satisfied, the initial efficiency can be improved at the same time as the capacity drop of the battery is minimized.
상기 반응물을 세척하여 상기 반응물 내 리튬 실리케이트를 일부 제거하는 단계에 있어서, 상기 세척은 물을 이용하여 수행될 수 있다. 상기 제거되는 리튬 실리케이트는 Li4SiO4를 포함할 수 있다. 본 발명의 제조 방법 과정에서 형성된 Li4SiO4는 물에 의해 쉽게 세척될 수 있는 리튬 실리케이트이다. 따라서, 별도의 물질, 예컨대 HCl 등의 산이 없더라도 물을 사용하여 상기 Li4SiO4을 반응물에서 쉽게 제거할 수 있다. 이에 따라, 음극 활물질의 제조 공정이 간소화될 수 있다. 또한, 상기 Li2SiO3 및 Li2Si2O5 는 수용성 리튬 실리케이트가 아니므로, 물에 의한 세척 시 제거되지 않고 음극 활물질 내에 잔류하게 된다. 적당한 함량의 Li2SiO3 및 Li2Si2O5에 의해 전지의 초기 효율이 개선될 수 있다. In the step of washing the reactant to partially remove lithium silicate in the reactant, the washing may be performed using water. The lithium silicate to be removed may include Li 4 SiO 4 . Li 4 SiO 4 formed in the process of the present invention is lithium silicate which can be easily washed with water. Therefore, Li 4 SiO 4 can be easily removed from the reactants by using water even if there is no acid such as HCl. Thus, the manufacturing process of the negative electrode active material can be simplified. In addition, since Li 2 SiO 3 and Li 2 Si 2 O 5 are not water-soluble lithium silicate, they are not removed by washing with water, but remain in the negative electrode active material. The initial efficiency of the battery can be improved by the appropriate amounts of Li 2 SiO 3 and Li 2 Si 2 O 5 .
본 발명의 다른 실시예에 따른 음극 활물질은 앞서 설명한 음극 활물질의 제조 방법에 의해 제조된 음극 활물질이다. 아울러, 본 발명의 또 다른 실시예에 따른 음극은 집전체 및 상기 집전체 상에 배치된 음극 활물질층을 포함할 수 있다. 상기 음극 활물질층은 상기 음극 활물질을 포함할 수 있다. 나아가, 상기 음극 활물질층은 바인더 및/또는 도전재를 더 포함할 수 있다. The negative electrode active material according to another embodiment of the present invention is the negative electrode active material prepared by the above-described method of manufacturing the negative electrode active material. In addition, the negative electrode according to another embodiment of the present invention may include a current collector and a negative electrode active material layer disposed on the current collector. The negative electrode active material layer may include the negative electrode active material. Further, the negative electrode active material layer may further include a binder and / or a conductive material.
상기 집전체는 당해 전지에 화학적 변화를 유발하지 않으면서 도전성을 가진 것이라면 되고, 특별히 제한되는 것은 아니다. 예를 들어, 상기 집전체로는 구리, 스테인리스 스틸, 알루미늄, 니켈, 티탄, 소성 탄소, 또는 알루미늄이나 스테인리스 스틸의 표면에 카본, 니켈, 티탄, 은 등으로 표면 처리한 것 등이 사용될 수 있다. 구체적으로는, 구리, 니켈과 같은 탄소를 잘 흡착하는 전이 금속을 집전체로 사용할 수 있다. 상기 집전체의 두께는 6㎛ 내지 20㎛일 수 있으나, 상기 집전체의 두께가 이에 제한되는 것은 아니다.The current collector is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery. For example, the current collector may be made of copper, stainless steel, aluminum, nickel, titanium, sintered carbon, or a surface of aluminum or stainless steel surface treated with carbon, nickel, titanium or silver. Specifically, a transition metal that adsorbs carbon well such as copper or nickel can be used as a current collector. The current collector may have a thickness of 6 to 20 탆, but the thickness of the current collector is not limited thereto.
상기 바인더는 폴리비닐리덴플루오라이드-헥사플루오로프로필렌 코폴리머(PVDF-co-HFP), 폴리비닐리덴플루오라이드(polyvinylidenefluoride), 폴리아크릴로니트릴(polyacrylonitrile), 폴리메틸메타크릴레이트(polymethylmethacrylate), 폴리비닐알코올, 카르복시메틸셀룰로오스(CMC), 전분, 히드록시프로필셀룰로오스, 재생 셀룰로오스, 폴리비닐피롤리돈, 테트라플루오로에틸렌, 폴리에틸렌, 폴리프로필렌, 폴리아크릴산, 에틸렌-프로필렌-디엔 모노머(EPDM), 술폰화 EPDM, 스티렌 부타디엔 고무(SBR), 불소 고무, 폴리 아크릴산 (poly acrylic acid) 및 이들의 수소를 Li, Na 또는 Ca 등으로 치환된 물질로 이루어진 군에서 선택되는 적어도 어느 하나를 포함할 수 있으며, 또한 이들의 다양한 공중합체를 포함할 수 있다.The binder may be selected from the group consisting of polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride, polyacrylonitrile, polymethylmethacrylate, poly Polypropylene, polyacrylic acid, ethylene-propylene-diene monomer (EPDM), liquor, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, And may include at least any one selected from the group consisting of polyvinylidene fluoride (EPDM), styrene butadiene rubber (SBR), fluorine rubber, poly acrylic acid, and materials in which hydrogen thereof is substituted with Li, Na, Ca, And may include various copolymers thereof.
상기 도전재는 당해 전지에 화학적 변화를 유발하지 않으면서 도전성을 가진 것이라면 특별히 제한되는 것은 아니며, 예를 들어, 천연 흑연이나 인조 흑연 등의 흑연; 카본블랙, 아세틸렌 블랙, 케첸 블랙, 채널 블랙, 파네스 블랙, 램프 블랙, 서멀 블랙 등의 카본블랙; 탄소 섬유나 금속 섬유 등의 도전성 섬유; 탄소 나노 튜브 등의 도전성 튜브; 플루오로카본, 알루미늄, 니켈 분말 등의 금속 분말; 산화아연, 티탄산 칼륨 등의 도전성 위스커; 산화 티탄 등의 도전성 금속 산화물; 폴리페닐렌 유도체 등의 도전성 소재 등이 사용될 수 있다.The conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, and examples thereof include graphite such as natural graphite and artificial graphite; Carbon black such as carbon black, acetylene black, Ketjen black, channel black, panes black, lamp black, and thermal black; Conductive fibers such as carbon fiber and metal fiber; Conductive tubes such as carbon nanotubes; Metal powders such as fluorocarbon, 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.
본 발명의 또 다른 실시예에 따른 이차 전지는, 음극, 양극, 상기 양극 및 음극 사이에 개재된 분리막, 및 전해질을 포함할 수 있으며, 상기 음극은 상술한 음극과 동일하다. 상기 음극에 대해서는 상술하였으므로, 구체적인 설명은 생략한다.The secondary battery according to another embodiment of the present invention may include a cathode, an anode, a separator interposed between the anode and the cathode, and an electrolyte, and the cathode is the same as the cathode described above. Since the negative electrode has been described above, a detailed description thereof will be omitted.
상기 양극은 양극 집전체 및 상기 양극 집전체 상에 형성되며, 상기 양극활물질을 포함하는 양극활물질층을 포함할 수 있다.The positive electrode may include a positive electrode collector and a positive electrode active material layer formed on the positive electrode collector and including the positive electrode active material.
상기 양극에 있어서, 양극 집전체는 전지에 화학적 변화를 유발하지 않으면서 도전성을 가진 것이라면 특별히 제한되는 것은 아니며, 예를 들어 스테인리스 스틸, 알루미늄, 니켈, 티탄, 소성 탄소 또는 알루미늄이나 스테인레스 스틸 표면에 탄소, 니켈, 티탄, 은 등으로 표면 처리한 것 등이 사용될 수 있다. 또, 상기 양극 집전체는 통상적으로 3 내지 500㎛의 두께를 가질 수 있으며, 상기 집전체 표면 상에 미세한 요철을 형성하여 양극활물질의 접착력을 높일 수도 있다. 예를 들어 필름, 시트, 호일, 네트, 다공질체, 발포체, 부직포체 등 다양한 형태로 사용될 수 있다.In the anode, the cathode current collector is not particularly limited as long as it has conductivity without causing a chemical change in the battery, and for example, a metal such as stainless steel, aluminum, nickel, titanium, sintered carbon, , Nickel, titanium, silver, or the like may be used. In addition, the cathode current collector may have a thickness of 3 to 500 탆, and fine unevenness may be formed on the surface of the current collector to increase the adhesive force of the cathode active material. For example, it can be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric.
상기 양극 활물질은 통상적으로 사용되는 양극 활물질일 수 있다. 구체적으로, 상기 양극 활물질은 리튬 코발트 산화물(LiCoO2), 리튬 니켈 산화물(LiNiO2) 등의 층상 화합물이나 1 또는 그 이상의 전이금속으로 치환된 화합물; LiFe3O4 등의 리튬 철 산화물; 화학식 Li1+c1Mn2-c1O4 (0≤c1≤0.33), LiMnO3, LiMn2O3, LiMnO2 등의 리튬 망간 산화물; 리튬 동 산화물(Li2CuO2); LiV3O8, V2O5, Cu2V2O7 등의 바나듐 산화물; 화학식 LiNi1-c2Mc2O2 (여기서, M은 Co, Mn, Al, Cu, Fe, Mg, B 및 Ga으로 이루어진 군에서 선택된 적어도 어느 하나이고, 0.01≤c2≤0.3를 만족한다)으로 표현되는 Ni 사이트형 리튬 니켈 산화물; 화학식 LiMn2-c3Mc3O2 (여기서, M은 Co, Ni, Fe, Cr, Zn 및 Ta 으로 이루어진 군에서 선택된 적어도 어느 하나이고, 0.01≤c3≤0.1를 만족한다) 또는 Li2Mn3MO8 (여기서, M은 Fe, Co, Ni, Cu 및 Zn으로 이루어진 군에서 선택된 적어도 어느 하나이다.)으로 표현되는 리튬 망간 복합 산화물; 화학식의 Li 일부가 알칼리토금속 이온으로 치환된 LiMn2O4 등을 들 수 있지만, 이들만으로 한정되는 것은 아니다. 상기 양극은 Li-metal일 수도 있다.The cathode active material may be a commonly used cathode active material. Specifically, the cathode active material may be a layered compound such as lithium cobalt oxide (LiCoO 2 ) or lithium nickel oxide (LiNiO 2 ) or a compound substituted with one or more transition metals; Lithium iron oxides such as LiFe 3 O 4 ; Formula Li 1 + c1 Mn 2-c1 O 4 (0≤c1≤0.33), LiMnO 3, the lithium manganese oxide such as LiMn 2 O 3, LiMnO 2; Lithium copper oxide (Li 2 CuO 2 ); Vanadium oxides such as LiV 3 O 8 , V 2 O 5 and Cu 2 V 2 O 7 ; Formula LiNi 1-c2 M c2 O 2 expressed as (where, M is at least one, satisfies 0.01≤c2≤0.3 selected from the group consisting of Co, Mn, Al, Cu, Fe, Mg, B and Ga) &Lt; / RTI &gt; Ni-type lithium nickel oxide; Formula LiMn 2-c3 M c3 O 2 ( where, M is Co, Ni, Fe, Cr, Zn , and is at least one selected from the group consisting of Ta, satisfies 0.01≤c3≤0.1) or Li 2 Mn 3 MO 8 (wherein M is at least one selected from the group consisting of Fe, Co, Ni, Cu and Zn); And LiMn 2 O 4 in which a part of Li in the formula is substituted with an alkaline earth metal ion. However, the present invention is not limited to these. The anode may be Li-metal.
상기 양극활물질층은 앞서 설명한 양극 활물질과 함께, 양극 도전재 및 양극 바인더를 포함할 수 있다.The positive electrode active material layer may include a positive electrode conductive material and a positive electrode binder together with the above-described positive electrode active material.
이때, 상기 양극 도전재는 전극에 도전성을 부여하기 위해 사용되는 것으로서, 구성되는 전지에 있어서, 화학변화를 야기하지 않고 전자 전도성을 갖는 것이면 특별한 제한없이 사용가능하다. 구체적인 예로는 천연 흑연이나 인조 흑연 등의 흑연; 카본 블랙, 아세틸렌블랙, 케첸블랙, 채널 블랙, 퍼네이스 블랙, 램프 블랙, 서머 블랙, 탄소섬유 등의 탄소계 물질; 구리, 니켈, 알루미늄, 은 등의 금속 분말 또는 금속 섬유; 산화아연, 티탄산 칼륨 등의 도전성 위스키; 산화 티탄 등의 도전성 금속 산화물; 또는 폴리페닐렌 유도체 등의 전도성 고분자 등을 들 수 있으며, 이들 중 1종 단독 또는 2종 이상의 혼합물이 사용될 수 있다. At this time, the positive electrode conductive material is used for imparting conductivity to the electrode, and the positive electrode conductive material can be used without particular limitation as long as it has electron conductivity without causing chemical change. Specific examples thereof include graphite such as natural graphite and artificial graphite; Carbon-based materials such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, summer black and carbon fiber; Metal powder or metal fibers such as copper, nickel, aluminum and silver; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; And polyphenylene derivatives. These may be used alone or in admixture of two or more.
또, 상기 양극 바인더는 양극 활물질 입자들 간의 부착 및 양극 활물질과 양극 집전체와의 접착력을 향상시키는 역할을 한다. 구체적인 예로는 폴리비닐리덴플로라이드(PVDF), 비닐리덴플루오라이드-헥사플루오로프로필렌 코폴리머(PVDF-co-HFP), 폴리비닐알코올, 폴리아크릴로니트릴(polyacrylonitrile), 카르복시메틸셀룰로우즈(CMC), 전분, 히드록시프로필셀룰로우즈, 재생 셀룰로우즈, 폴리비닐피롤리돈, 테트라플루오로에틸렌, 폴리에틸렌, 폴리프로필렌, 에틸렌-프로필렌-디엔 폴리머(EPDM), 술폰화-EPDM, 스티렌 부타디엔 고무(SBR), 불소 고무, 또는 이들의 다양한 공중합체 등을 들 수 있으며, 이들 중 1종 단독 또는 2종 이상의 혼합물이 사용될 수 있다.In addition, the positive electrode binder improves adhesion between the positive electrode active material particles and adhesion between the positive electrode active material and the positive electrode collector. Specific examples include polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethylcellulose ), Starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated-EPDM, styrene butadiene rubber (SBR), fluororubber, and various copolymers thereof. One kind or a mixture of two or more kinds of them may be used.
분리막으로는 음극과 양극을 분리하고 리튬 이온의 이동 통로를 제공하는 것으로, 통상 이차 전지에서 분리막으로 사용되는 것이라면 특별한 제한 없이 사용가능하며, 특히 전해질의 이온 이동에 대하여 저저항이면서 전해액 함습 능력이 우수한 것이 바람직하다. 구체적으로는 다공성 고분자 필름, 예를 들어 에틸렌 단독중합체, 프로필렌 단독중합체, 에틸렌/부텐 공중합체, 에틸렌/헥센 공중합체 및 에틸렌/메타크릴레이트 공중합체 등과 같은 폴리올레핀계 고분자로 제조한 다공성 고분자 필름 또는 이들의 2층 이상의 적층 구조체가 사용될 수 있다. 또 통상적인 다공성 부직포, 예를 들어 고융점의 유리 섬유, 폴리에틸렌테레프탈레이트 섬유 등으로 된 부직포가 사용될 수도 있다. 또, 내열성 또는 기계적 강도 확보를 위해 세라믹 성분 또는 고분자 물질이 포함된 코팅된 분리막이 사용될 수도 있으며, 선택적으로 단층 또는 다층 구조로 사용될 수 있다.The separator separates the cathode and the anode and provides a passage for lithium ion. The separator can be used without any particular limitation as long as it is used as a separator in a secondary battery. In particular, the separator can be used with low resistance against electrolyte migration, . Specifically, porous polymer films such as porous polymer films made of polyolefin-based polymers such as ethylene homopolymers, propylene homopolymers, ethylene / butene copolymers, ethylene / hexene copolymers and ethylene / methacrylate copolymers, May be used. Further, a nonwoven fabric made of a conventional porous nonwoven fabric, for example, glass fiber of high melting point, polyethylene terephthalate fiber, or the like may be used. In order to secure heat resistance or mechanical strength, a coated separator containing a ceramic component or a polymer material may be used, and the separator may be selectively used as a single layer or a multilayer structure.
상기 전해질은 전해질로는 리튬 이차전지 제조시 사용 가능한 유기계 액체 전해질, 무기계 액체 전해질, 고체 고분자 전해질, 겔형 고분자 전해질, 고체 무기 전해질, 용융형 무기 전해질 등을 들 수 있으며, 이들로 한정되는 것은 아니다.Examples of the electrolyte include an organic liquid electrolyte, an inorganic liquid electrolyte, a solid polymer electrolyte, a gel polymer electrolyte, a solid inorganic electrolyte, and a molten inorganic electrolyte that can be used in the production of a lithium secondary battery, but are not limited thereto.
구체적으로, 상기 전해질은 비수계 유기용매와 금속염을 포함할 수 있다. Specifically, the electrolyte may include a non-aqueous organic solvent and a metal salt.
상기 비수계 유기용매로는, 예를 들어, N-메틸-2-피롤리디논, 프로필렌 카보네이트, 에틸렌 카보네이트, 부틸렌 카보네이트, 디메틸 카보네이트, 디에틸 카보네이트, 감마-부틸로 락톤, 1,2-디메톡시 에탄, 테트라히드록시 프랑(franc), 2-메틸 테트라하이드로푸란, 디메틸술폭시드, 1,3-디옥소런, 포름아미드, 디메틸포름아미드, 디옥소런, 아세토니트릴, 니트로메탄, 포름산 메틸, 초산메틸, 인산 트리에스테르, 트리메톡시 메탄, 디옥소런 유도체, 설포란, 메틸 설포란, 1,3-디메틸-2-이미다졸리디논, 프로필렌 카보네이트 유도체, 테트라하이드로푸란 유도체, 에테르, 피로피온산 메틸, 프로피온산 에틸 등의 비양자성 유기용매가 사용될 수 있다.Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma-butylolactone, Tetrahydrofuran, tetrahydrofuran, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, Examples of the organic solvent include methyl acetate, phosphoric acid triester, trimethoxy methane, dioxolane derivatives, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, Propylenic organic solvents such as methylmethyl, ethylpropionate and the like can be used.
특히, 상기 카보네이트계 유기 용매 중 고리형 카보네이트인 에틸렌 카보네이트 및 프로필렌 카보네이트는 고점도의 유기 용매로서 유전율이 높아 리튬염을 잘 해리시키므로 바람직하게 사용될 수 있으며, 이러한 고리형 카보네이트에 디메틸카보네이트 및 디에틸카보네이트와 같은 저점도, 저유전율 선형 카보네이트를 적당한 비율로 혼합하여 사용하면 높은 전기 전도율을 갖는 전해질을 만들 수 있어 더욱 바람직하게 사용될 수 있다. In particular, ethylene carbonate and propylene carbonate, which are cyclic carbonates in the carbonate-based organic solvent, can be preferably used because they have high permittivity as a high viscosity organic solvent and dissociate the lithium salt well. To such a cyclic carbonate, dimethyl carbonate and diethyl carbonate When the same low viscosity and low dielectric constant linear carbonate are mixed in an appropriate ratio, an electrolyte having a high electric conductivity can be prepared, and thus it can be used more preferably.
상기 금속염은 리튬염을 사용할 수 있고, 상기 리튬염은 상기 비수 전해액에 용해되기 좋은 물질로서, 예를 들어, 상기 리튬염의 음이온으로는 F-, Cl-, I-, NO3 -, N(CN)2 -, BF4 -, ClO4 -, PF6 -, (CF3)2PF4 -, (CF3)3PF3 -, (CF3)4PF2 -, (CF3)5PF-, (CF3)6P-, CF3SO3 -, CF3CF2SO3 -, (CF3SO2)2N-, (FSO2)2N-, CF3CF2(CF3)2CO-, (CF3SO2)2CH-, (SF5)3C-, (CF3SO2)3C-, CF3(CF2)7SO3 -, CF3CO2 -, CH3CO2 -, SCN- 및 (CF3CF2SO2)2N-로 이루어진 군으로부터 선택되는 1종 이상을 사용할 수 있다.The metal salt may be a lithium salt, and the lithium salt may be soluble in the non-aqueous electrolyte. Examples of the anion of the lithium salt include F - , Cl - , I - , NO 3 - , N ) 2 -, BF 4 -, ClO 4 -, PF 6 -, (CF 3) 2 PF 4 -, (CF 3) 3 PF 3 -, (CF 3) 4 PF 2 -, (CF 3) 5 PF - , (CF 3) 6 P - , CF 3 SO 3 -, CF 3 CF 2 SO 3 -, (CF 3 SO 2) 2 N -, (FSO 2) 2 N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2 ) 2 CH -, (SF 5) 3 C -, (CF 3 SO 2) 3 C -, CF 3 (CF 2) 7 SO 3 -, CF 3 CO 2 -, CH 3 At least one selected from the group consisting of CO 2 - , SCN - and (CF 3 CF 2 SO 2 ) 2 N - can be used.
상기 전해질에는 상기 전해질 구성 성분들 외에도 전지의 수명특성 향상, 전지 용량 감소 억제, 전지의 방전 용량 향상 등을 목적으로 예를 들어, 디플루오로 에틸렌카보네이트 등과 같은 할로알킬렌카보네이트계 화합물, 피리딘, 트리에틸포스파이트, 트리에탄올아민, 환상 에테르, 에틸렌 디아민, n-글라임(glyme), 헥사인산 트리아미드, 니트로벤젠 유도체, 유황, 퀴논 이민 염료, N-치환옥사졸리디논, N,N-치환 이미다졸리딘, 에틸렌 글리콜 디알킬 에테르, 암모늄염, 피롤, 2-메톡시 에탄올 또는 삼염화 알루미늄 등의 첨가제가 1종 이상 더 포함될 수도 있다.In addition to the electrolyte components, the electrolyte may contain, for example, a haloalkylene carbonate-based compound such as difluoroethylene carbonate or the like, pyridine, triethanolamine, or the like for the purpose of improving lifetime characteristics of the battery, Ethyl phosphite, triethanol amine, cyclic ether, ethylenediamine, glyme, hexametriamide, nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, At least one additive such as benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol, benzyl alcohol,
본 발명의 또 다른 실시예에 따르면, 상기 이차 전지를 단위 셀로 포함하는 전지 모듈 및 이를 포함하는 전지 팩을 제공한다. 상기 전지 모듈 및 전지 팩은 고용량, 높은 율속 특성 및 사이틀 특성을 갖는 상기 이차 전지를 포함하므로, 전기자동차, 하이브리드 전기자동차, 플러그-인 하이브리드 전기자동차 및 전력 저장용 시스템으로 이루어진 군에서 선택되는 중대형 디바이스의 전원으로 이용될 수 있다.According to another embodiment of the present invention, there is provided a battery module including the secondary battery as a unit cell and a battery pack including the same. Since the battery module and the battery pack include the secondary battery having a high capacity, high speed-rate characteristics, and a cycling characteristic, the battery module and the battery pack can be suitably used as a middle- or large-sized device selected from the group consisting of electric vehicles, hybrid electric vehicles, plug- As shown in FIG.
이하, 본 발명의 이해를 돕기 위하여 바람직한 실시예를 제시하나, 상기 실시예는 본 기재를 예시하는 것일 뿐 본 기재의 범주 및 기술사상 범위 내에서 다양한 변경 및 수정이 가능함은 당업자에게 있어서 명백한 것이며, 이러한 변형 및 수정이 첨부된 특허청구범위에 속하는 것은 당연한 것이다.It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the appended claims. Such variations and modifications are intended to be within the scope of the appended claims.
실시예 및 비교예Examples and Comparative Examples
실시예 1: 전지의 제조Example 1: Preparation of battery
(1) 음극 활물질의 제조(1) Preparation of negative electrode active material
1) SiOx(0<x<2) 입자와 Li2O의 혼합물 형성1) Formation of mixture of SiO x (0 <x <2) particles and Li 2 O
평균 입경(D50)이 5㎛인 SiO 입자 3g과 평균 입경(D50)이 3㎛인 Li2O 1g을 볼밀을 통해 30분간 동안 교반하여, 혼합물을 형성하였다.3 g of SiO particles having an average particle diameter (D 50 ) of 5 탆 and 1 g of Li 2 O having an average particle diameter (D 50 ) of 3 탆 were stirred for 30 minutes through a ball mill to form a mixture.
2) 열처리 공정2) Heat treatment process
상기 혼합물 3g을 반응로에 투입하고, 상기 반응로 온도를 550℃로 하여 3시간 동안 열처리하여 반응물을 형성하였다. 형성된 상기 반응물 내의 리튬 실리케이트 각각의 함량을 표 1에 나타내었다.3 g of the mixture was charged into a reaction furnace, and the mixture was heat-treated at 550 DEG C for 3 hours to form a reaction product. The contents of each of the lithium silicates in the reactants formed are shown in Table 1.
3) 리튬 실리케이트의 제거3) Removal of lithium silicate
상기 반응물을 물에 투입하고, 30분 동안 교반(세척)하여 반응물 내 리튬 실리케이트를 일부 제거하였다. 이를 통해, 실시예 1의 음극 활물질을 제조하였다. 제조된 음극 활물질 내 실리콘 결정립의 크기를 표 1에 나타내었다.The reaction was poured into water and stirred (washed) for 30 minutes to partially remove lithium silicate in the reaction. Thus, the negative electrode active material of Example 1 was prepared. Table 1 shows the sizes of the silicon crystal grains in the prepared negative electrode active material.
(2) 음극의 제조(2) Manufacture of cathodes
상기 제조된 음극 활물질, 흑연, 도전재인 카본 블랙, 바인더인 카르복시메틸 셀룰로오스(Carboxylmethyl cellulose, CMC) 및 스티렌 부타디엔 고무(Styrene butadiene rubber, SBR)을 4.8:91:1:1.7:1.5의 중량비로 혼합하여 혼합물 5g을 제조하였다. 상기 혼합물에 증류수를 28.9g 첨가하여 음극 슬러리를 제조하였다. 상기 음극 슬러리를 두께가 20㎛인 음극 집전체인 구리(Cu) 금속 박막에 도포, 건조하였다. 이때 순환되는 공기의 온도는 60℃였다. 이어서, 압연(roll press)하고 130℃의 진공 오븐에서 12시간 동안 건조한 뒤, 1.4875cm2의 원형으로 타발하여 음극을 제조하였다.Carbon methylmethyl cellulose (CMC) and styrene butadiene rubber (SBR) were mixed in a weight ratio of 4.8: 91: 1: 1.7: 1.5 to prepare a negative electrode active material, graphite, carbon black as a conductive material, 5 g of a mixture was prepared. 28.9 g of distilled water was added to the mixture to prepare an anode slurry. The negative electrode slurry was applied to a copper (Cu) metal thin film as an anode current collector having a thickness of 20 탆 and dried. The temperature of the circulated air was 60 ° C. Subsequently, this was rolled, dried in a vacuum oven at 130 DEG C for 12 hours, and then drum-shaped in a circular shape of 1.4875 cm &lt; 2 &gt; to produce a negative electrode.
(3) 이차 전지의 제조(3) Production of secondary battery
제조된 음극을 1.7671㎠의 원형으로 절단한 리튬(Li) 금속 박막을 양극으로 하였다. 상기 양극과 음극 사이에 다공성 폴리에틸렌의 분리막을 개재하고, 메틸에틸카보네이트(EMC)와 에틸렌카보네이트(EC)의 혼합 부피비가 7:3인 혼합 용액에 0.5 중량%로 용해된 비닐렌 카보네이트를 용해시키고, 1M 농도의 LiPF6가 용해된 전해액을 주입하여, 리튬 코인 하프 셀(coin half-cell)을 제조하였다.The prepared negative electrode was cut into a circle of 1.7671 cm &lt; 2 &gt; and a lithium metal thin film was used as the positive electrode. 0.5% by weight of vinylene carbonate dissolved in a mixed solution of methyl ethyl carbonate (EMC) and ethylene carbonate (EC) at a mixing volume ratio of 7: 3 was placed between the anode and the cathode through a separator of porous polyethylene, And an electrolytic solution in which 1 M LiPF 6 was dissolved was injected to prepare a lithium coin half-cell.
실시예 2: 전지의 제조Example 2: Preparation of battery
실시예 1의 열처리 공정에서, 상기 반응로 온도를 450℃로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 450 캜 in the heat treatment process of Example 1.
실시예 3: 전지의 제조Example 3: Preparation of battery
실시예 1의 열처리 공정에서, 열처리 시간을 5시간으로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the heat treatment time was changed to 5 hours in the heat treatment step of Example 1.
실시예 4: 전지의 제조Example 4: Preparation of battery
실시예 1의 열처리 공정에서, 열처리 시간을 6시간으로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the heat treatment time in Example 1 was changed to 6 hours.
비교예 1: 전지의 제조Comparative Example 1: Manufacture of battery
실시예 1의 열처리 공정에서, 상기 반응로 온도를 900℃로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 900 ° C. in the heat treatment step of Example 1.
비교예 2: 전지의 제조Comparative Example 2: Manufacture of battery
실시예 1의 열처리 공정에서, 상기 반응로 온도를 300℃로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reactor was changed to 300 캜 in the heat treatment step of Example 1.
비교예 3: 전지의 제조Comparative Example 3: Preparation of battery
실시예 1의 열처리 공정에서, 상기 반응로 온도를 650℃로 한 것을 제외하고는 실시예 1과 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.A negative electrode active material, a negative electrode and a secondary battery were prepared in the same manner as in Example 1, except that the temperature of the reaction furnace was changed to 650 ° C in the heat treatment step of Example 1.
비교예 4: 전지의 제조Comparative Example 4: Manufacture of battery
(1) 음극 활물질의 제조(1) Preparation of negative electrode active material
1) SiOx(0<x<2) 입자와 Li의 혼합물 형성1) Formation of mixture of SiO x (0 <x <2) particles and Li
평균 입경(D50)이 5㎛인 SiO 입자 3g과 평균 입경(D50)이 20㎛인 Li 0.92g을 볼밀을 통해 30분 동안 교반하여, 혼합물을 형성하였다.3 g of SiO particles having an average particle diameter (D 50 ) of 5 μm and 0.92 g of Li having an average particle diameter (D 50 ) of 20 μm were stirred for 30 minutes through a ball mill to form a mixture.
2) 열처리 공정2) Heat treatment process
상기 혼합물 3g을 반응로에 투입하고, 상기 반응로 온도를 550℃로 하여 3시간 동안 열처리하여 반응물을 형성하였다. 상기 반응물 내의 Li4SiO4 함량은 표 1에 나타내었다.3 g of the mixture was charged into a reaction furnace, and the mixture was heat-treated at 550 DEG C for 3 hours to form a reaction product. The Li 4 SiO 4 content in the reactant is shown in Table 1.
3) 리튬 실리케이트의 제거3) Removal of lithium silicate
상기 반응물을 물에 투입하고, 30분 동안 교반(세척)하여 반응물 내 리튬 실리케이트를 일부 제거하였다. 이를 통해, 비교예 3의 음극 활물질을 제조하였다. 제조된 음극 활물질 내 실리콘 결정립의 크기를 표 1에 나타내었다.The reaction was poured into water and stirred (washed) for 30 minutes to partially remove lithium silicate in the reaction. Thus, the negative electrode active material of Comparative Example 3 was prepared. Table 1 shows the sizes of the silicon crystal grains in the prepared negative electrode active material.
(2) 음극 및 이차 전지의 제조(2) Manufacture of cathode and secondary battery
실시예 1과 동일한 방법으로 음극 및 이차 전지를 제조하였다.A negative electrode and a secondary battery were produced in the same manner as in Example 1.
비교예 5: 전지의 제조Comparative Example 5: Manufacture of battery
비교예 4의 열처리 공정에서, 상기 반응로 온도를 900℃로 한 것을 제외하고는 비교예 4와 동일한 방법으로 음극 활물질, 음극 및 이차 전지를 제조하였다.In the heat treatment step of Comparative Example 4, an anode active material, a cathode and a secondary battery were prepared in the same manner as in Comparative Example 4, except that the temperature of the reactor was changed to 900 ° C.
Li4SiO4 함량(wt%)Li 4 SiO 4 content (wt%) Li2SiO3 함량(wt%)Li 2 SiO 3 content (wt%) Li2Si2O5 함량(wt%)Li 2 Si 2 O 5 content (wt%) 실리콘 결정립 크기(nm)Silicon grain size (nm)
실시예 1Example 1 48.748.7 0.80.8 2.02.0 00
실시예 2Example 2 42.142.1 0.30.3 0.50.5 00
실시예 3Example 3 48.648.6 0.80.8 2.02.0 00
실시예 4Example 4 48.748.7 0.80.8 1.91.9 00
비교예 1Comparative Example 1 30.730.7 14.014.0 22.322.3 11.311.3
비교예 2Comparative Example 2 23.123.1 0.40.4 0.80.8 00
비교예 3Comparative Example 3 40.640.6 2.52.5 3.13.1 6.66.6
비교예 4Comparative Example 4 7.37.3 3.23.2 3.23.2 00
비교예 5Comparative Example 5 25.825.8 11.411.4 11.411.4 11.111.1
상기 표 1에서, 리튬 실리케이트의 함량은 열처리 후, 세척 전의 반응물 전체 중량을 기준으로 한 함량이며, XRD 정량 분석으로 측정되었다. 또한, 상기 표 1에서 실리콘 결정립의 크기는 XRD scherrer equation의 방법으로 측정되었다.In the above Table 1, the lithium silicate The content was based on the total weight of the reactants after the heat treatment and before washing, and was measured by XRD quantitative analysis. In Table 1, the size of silicon grains was measured by the XRD scherrer equation.
시험예 1: 방전 용량, 초기 효율, 용량 유지율 평가Test Example 1: Evaluation of Discharge Capacity, Initial Efficiency, Capacity Retention Rate
실시예 1 내지 4 및 비교예 1 내지 5의 이차 전지에 대해 충·방전을 수행하여, 방전 용량, 초기 효율 및 용량 유지율을 평가하였고, 이를 하기 표 2에 기재하였다.The secondary batteries of Examples 1 to 4 and Comparative Examples 1 to 5 were charged / discharged to evaluate the discharge capacity, initial efficiency and capacity retention ratio, and these are shown in Table 2 below.
한편, 1회 사이클과 2회 사이클은 0.1C로 충·방전하였고, 3회 사이클부터 49회 싸이클까지는 0.5C로 충·방전을 수행하였다. 50회 사이클은 충전(리튬이 음극에 들어있는 상태)상태에서 종료하였다.On the other hand, the first cycle and the second cycle were charged and discharged at 0.1 C, and charge and discharge were performed at 0.5 C from the third cycle to the 49th cycle. The 50 cycles were terminated in the state of charge (state in which lithium was contained in the cathode).
충전 조건: CC(정전류)/CV(정전압)(5mV/0.005C current cut-off) Charging conditions: CC (constant current) / CV (constant voltage) (5mV / 0.005C current cut-off)
방전 조건: CC(정전류) 조건 1.5VDischarge Condition: CC (Constant Current) Condition 1.5V
1회 충방전 시의 결과를 통해, 방전 용량(mAh/g) 및 초기 효율(%)을 도출하였다. 구체적으로 초기 효율(%)은 다음과 같은 계산에 의해 도출되었다.The discharge capacity (mAh / g) and the initial efficiency (%) were derived from the results of one charge / discharge cycle. Specifically, the initial efficiency (%) was derived by the following calculation.
초기 효율(%) = (1회 방전 후 방전 용량 / 1회 충전 용량)×100Initial efficiency (%) = (discharge capacity after one discharge / capacity of one charge) x 100
용량 유지율과 전극 두께 변화율은 각각 다음과 같은 계산에 의해 도출되었다. The capacity retention rate and the electrode thickness change ratio were derived by the following calculation, respectively.
용량 유지율(%) = (49회 방전 용량 / 1회 방전 용량)×100Capacity retention rate (%) = (49 times discharge capacity / one time discharge capacity) x 100
전지battery 방전 용량(mAh/g)Discharge capacity (mAh / g) 초기 효율(%)Initial efficiency (%) 용량 유지율(%)Capacity retention rate (%)
실시예 1Example 1 405.5405.5 89.989.9 73.273.2
실시예 2Example 2 405.2405.2 89.689.6 72.972.9
실시예 3Example 3 405.5405.5 89.889.8 73.173.1
실시예 4Example 4 405.4405.4 89.989.9 73.273.2
비교예 1Comparative Example 1 398.1398.1 89.589.5 68.968.9
비교예 2Comparative Example 2 401.6401.6 86.086.0 70.170.1
비교예 3Comparative Example 3 404.0404.0 89.689.6 69.569.5
비교예 4Comparative Example 4 400.8400.8 86.286.2 70.370.3
비교예 5Comparative Example 5 405.3405.3 89.689.6 67.167.1
상기 표 1 및 표 2를 참조하며, Li2O를 사용하고 각각 550℃, 450℃의 적절한 온도를 사용한 실시예 1 내지 4의 경우, 실리콘 결정립이 형성되지 않아서 용량 유지율이 높은 것을 알 수 있다. 또한, 실시예 1 내지 4의 경우, 중간 생성물(세척 전)의 수용성 리튬 실리케이트(Li4SiO4)의 함량이 높으므로, SiO의 환원이 원활하게 진행되었기에, 전지 용량이 개선될 수 있음을 알 수 있다. 아울러, 물에 의해 세척되지 않는 Li2SiO3 및 Li2Si2O5이 적당량으로 존재하기에, 초기 효율이 개선될 수 있음을 확인하였다.한편, Li2O를 사용하고 900℃의 높은 온도를 사용한 비교예 1의 경우, 실리콘 결정립이 과도하게 성장하여 용량 유지율이 낮은 것을 알 수 있다. 또한, Li2SiO3 및 Li2Si2O5가 지나치게 큰 함량으로 존재하여, 전지의 용량 특성이 지나치게 열악한 것을 확인하였다. Referring to Tables 1 and 2, it can be seen that in Examples 1 to 4 using Li 2 O and at appropriate temperatures of 550 ° C and 450 ° C, silicon crystal grains were not formed and the capacity retention rate was high. Further, in Examples 1 to 4, since the content of the water-soluble lithium silicate (Li 4 SiO 4 ) in the intermediate product (before washing) was high, the reduction of SiO 2 proceeded smoothly, . In addition, it was confirmed that the initial efficiency can be improved because Li 2 SiO 3 and Li 2 Si 2 O 5 which are not washed by water exist in appropriate quantities. On the other hand, when Li 2 O is used and a high temperature It is found that the silicon crystal grains are excessively grown and the capacity retention ratio is low. In addition, it was confirmed that Li 2 SiO 3 and Li 2 Si 2 O 5 were present in an excessively large content, and the capacity characteristics of the battery were extremely poor.
또한, Li2O를 사용하고 650℃의 높은 온도를 사용한 비교예 3의 경우에도, 실리콘 결정립이 과도하게 성장하였으며, 용량 유지율이 낮았다. 또한, Li2SiO3 및 Li2Si2O5가 지나치게 큰 함량으로 존재하여, 전지의 용량 특성이 열악한 것을 확인하였다. Also, in Comparative Example 3 where Li 2 O was used and a high temperature of 650 캜 was used, the silicon crystal grains were excessively grown and the capacity retention rate was low. In addition, it was confirmed that Li 2 SiO 3 and Li 2 Si 2 O 5 exist in an excessively large content, and the capacity characteristics of the battery are poor.
Li2O를 사용하고 300℃의 낮은 온도를 사용한 비교예 2과 Li를 사용하고 550℃의 낮은 온도를 사용한 비교예 3의 경우, 실리콘 결정립이 발견되지는 않으나, 적은 양의 Li4SiO4가 형성된 점에서 SiO의 환원이 원활하게 이루어지지 않았음을 알 수 있다. 이에 따라, 초기 효율, 방전 용량, 용량 유지율 개선 효과가 미비하다.Comparative Example 2 using Li 2 O and Comparative Example 2 using Li at a low temperature and Comparative Example 3 using Li at a low temperature of 550 ° C did not find silicon grains but a small amount of Li 4 SiO 4 It can be seen that the reduction of SiO was not performed smoothly at the formed point. Thus, the effect of improving the initial efficiency, the discharge capacity, and the capacity retention rate is insufficient.
Li을 사용하고 550℃에서 열처리를 한 비교예 4의 경우, Li2SiO3 및 Li2Si2O5가 지나치게 큰 함량으로 존재하여, 전지의 용량 특성이 열악한 것을 확인하였다.In the case of Comparative Example 4 in which Li was used and subjected to heat treatment at 550 캜, Li 2 SiO 3 and Li 2 Si 2 O 5 were present in an excessively large content, and the capacity characteristics of the battery were poor.
Li을 사용하고 900℃의 높은 온도에서 열처리를 한 비교예 5의 경우, 다량의 리튬 실리케이트가 형성되어 초기 효율 상승 효과가 있으나, 결정립이 과도하게 성장하여 용량 유지율이 낮은 것을 알 수 있다.In Comparative Example 5 in which Li was used and subjected to a heat treatment at a high temperature of 900 캜, a large amount of lithium silicate was formed to increase the initial efficiency, but the crystal grains were excessively grown and the capacity retention rate was low.
한편, 실시예 1과 실시예 2를 비교하면, 550℃에서 열처리한 실시예 1의 방전 용량, 초기 효율, 용량 유지율이 450℃에서 열처리한 실시예 2보다 뛰어난 것을 알 수 있다. 또한, 실시예 1, 실시예 3 및 실시예 4를 비교하면, 열처리 시간이 5시간을 초과하는 실시예 4의 경우, 3시간 열처리한 실시예 1 및 5시간 열처리한 실시예 3의 효과와 동등 수준임을 알 수 있다. 이에, 공정 효율성을 위해서 3시간 내지 5시간의 열처리를 진행하는 것이 가장 바람직한 것으로 보인다.On the other hand, comparing Example 1 with Example 2, it can be seen that the discharge capacity, initial efficiency, and capacity retention rate of Example 1 heat-treated at 550 ° C are superior to those of Example 2 that was heat-treated at 450 ° C. Comparing Example 1, Example 3 and Example 4, it was confirmed that Example 4 in which the heat treatment time exceeded 5 hours was equivalent to Example 1 in which heat treatment for 3 hours was performed and Example 3 for heat treatment for 5 hours . Therefore, it is most preferable to conduct the heat treatment for 3 hours to 5 hours for the process efficiency.

Claims (10)

  1. SiO2를 포함하는 SiOx(0<x<2) 입자와 Li2O를 혼합하여 혼합물을 형성하는 단계;Mixing Li 2 O with SiO x (0 < x < 2) particles containing SiO 2 to form a mixture;
    상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계; 및Heat-treating the mixture at 400 ° C to 600 ° C to form a reactant; And
    상기 반응물을 세척하여 상기 반응물 내 리튬 실리케이트를 일부 제거하는 단계;를 포함하는 음극 활물질 제조 방법.And washing the reactant to partially remove lithium silicate in the reactant.
  2. 청구항 1에 있어서,The method according to claim 1,
    상기 열처리는 500℃ 내지 600℃에서 수행되는 음극 활물질 제조 방법.Wherein the heat treatment is performed at a temperature of 500 ° C to 600 ° C.
  3. 청구항 1에 있어서,The method according to claim 1,
    상기 열처리는 3시간 내지 5시간 동안 수행되는, 음극 활물질 제조 방법.Wherein the heat treatment is performed for 3 hours to 5 hours.
  4. 청구항 1에 있어서,The method according to claim 1,
    상기 제거되는 리튬 실리케이트는 Li4SiO4를 포함하는, 음극 활물질 제조 방법.Wherein the lithium silicate to be removed comprises Li 4 SiO 4 .
  5. 청구항 1에 있어서,The method according to claim 1,
    상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계에 있어서,Treating the mixture at 400 ° C to 600 ° C to form a reactant,
    상기 열처리하여 형성된 반응물은 Li4SiO4를 포함하며,The reactant formed by the heat treatment includes Li 4 SiO 4 ,
    상기 Li4SiO4은 상기 반응물 전체 중량 중 40중량% 내지 60중량%로 포함되는, 음극 활물질 제조 방법.Wherein the Li 4 SiO 4 is contained in an amount of 40 wt% to 60 wt% of the total weight of the reactants.
  6. 청구항 1에 있어서,The method according to claim 1,
    상기 혼합물을 400℃ 내지 600℃에서 열처리하여 반응물을 형성하는 단계에 있어서,Treating the mixture at 400 ° C to 600 ° C to form a reactant,
    상기 열처리하여 형성된 반응물은 Li2SiO3 및 Li2Si2O5 중 적어도 어느 하나를 포함하며,The reactant formed by the heat treatment includes at least one of Li 2 SiO 3 and Li 2 Si 2 O 5 ,
    상기 Li2SiO3 및 상기 Li2Si2O5의 총 함량은 상기 열처리하여 형성된 반응물 전체 중량을 기준으로 0.3중량% 내지 4중량%인, 음극 활물질 제조 방법.Wherein the total content of Li 2 SiO 3 and Li 2 Si 2 O 5 is 0.3 wt% to 4 wt% based on the total weight of reactants formed by the heat treatment.
  7. 청구항 1에 있어서,The method according to claim 1,
    상기 세척은 물을 이용하여 수행되는 음극 활물질 제조 방법.Wherein the cleaning is performed using water.
  8. 청구항 1에 있어서,The method according to claim 1,
    상기 혼합물을 형성하는 단계에 있어서,In the step of forming the mixture,
    상기 SiOx(0<x<2) 입자와 상기 Li2O는 1:0.1 내지 1:0.666의 중량비로 혼합되는 음극 활물질 제조 방법.Wherein the SiO x (0 <x <2) particles and the Li 2 O are mixed in a weight ratio of 1: 0.1 to 1: 0.666.
  9. 청구항 1에 있어서,The method according to claim 1,
    상기 SiOx(0<x<2) 입자의 평균 입경(D50)은 3㎛ 내지 10㎛인 음극 활물질의 제조 방법.Wherein the average particle diameter (D 50 ) of the SiO x (0 <x <2) particles is 3 μm to 10 μm.
  10. 청구항 1에 있어서,The method according to claim 1,
    상기 Li2O의 평균 입경(D50)은 1㎛ 내지 10㎛인 음극 활물질의 제조 방법.Wherein the Li 2 O has an average particle diameter (D 50 ) of 1 μm to 10 μm.
PCT/KR2018/012435 2017-10-19 2018-10-19 Method for producing negative active material WO2019078680A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/754,388 US11515515B2 (en) 2017-10-19 2018-10-19 Method of preparing negative electrode active material

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR10-2017-0135616 2017-10-19
KR20170135616 2017-10-19
KR10-2018-0124981 2018-10-19
KR1020180124981A KR102290960B1 (en) 2017-10-19 2018-10-19 Method for preparing negative electrode active material

Publications (2)

Publication Number Publication Date
WO2019078680A2 true WO2019078680A2 (en) 2019-04-25
WO2019078680A3 WO2019078680A3 (en) 2019-06-06

Family

ID=66173393

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2018/012435 WO2019078680A2 (en) 2017-10-19 2018-10-19 Method for producing negative active material

Country Status (1)

Country Link
WO (1) WO2019078680A2 (en)

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6123430B2 (en) * 2013-03-29 2017-05-10 日本電気株式会社 Secondary battery and negative electrode active material
JP6359836B2 (en) * 2014-02-07 2018-07-18 信越化学工業株式会社 Negative electrode material for nonaqueous electrolyte secondary battery, negative electrode for nonaqueous electrolyte secondary battery, method for producing the same, and nonaqueous electrolyte secondary battery
US10879531B2 (en) * 2015-10-26 2020-12-29 Lg Chem, Ltd. Negative electrode active particle and method for manufacturing the same
JP6448510B2 (en) * 2015-11-05 2019-01-09 信越化学工業株式会社 Method for producing negative electrode active material for nonaqueous electrolyte secondary battery and method for producing nonaqueous electrolyte secondary battery
KR101937020B1 (en) * 2017-03-29 2019-01-09 포항공과대학교 산학협력단 Synthesis method of silicon composite and anodes for li-ion battery and li-ion battery having the same

Also Published As

Publication number Publication date
WO2019078680A3 (en) 2019-06-06

Similar Documents

Publication Publication Date Title
WO2019078690A2 (en) Negative active material, negative electrode comprising negative active material, and secondary battery comprising negative electrode
WO2015030402A1 (en) Lithium transition metal composite particles, method for preparing same, and positive active materials comprising same
WO2019112390A1 (en) Anode active material for lithium secondary battery and method for manufacturing same
WO2019151774A1 (en) Anode active material, preparation method for anode active material, anode comprising anode active material, and secondary battery comprising anode
WO2018164405A1 (en) Anode active material, anode comprising anode active material, and secondary battery comprising anode
WO2018208111A1 (en) Negative electrode active material, negative electrode comprising negative electrode active material, and secondary battery comprising negative electrode
WO2017164702A1 (en) Negative electrode and method for manufacturing same
WO2019172661A1 (en) Method for manufacturing negative electrode
WO2019078544A1 (en) Negative electrode for lithium secondary battery, and lithium secondary battery comprising same
WO2018203599A1 (en) Anode active material, anode comprising anode active material, secondary battery comprising anode, and method for preparing anode active material
WO2018088735A1 (en) Anode and method for fabricating same
WO2021025370A1 (en) Cathode active material for lithium secondary battery
WO2019103499A1 (en) Anode active material for lithium secondary battery, and preparation method therefor
WO2019093830A1 (en) Negative electrode active material, negative electrode comprising same negative electrode active material, and secondary battery comprising same negative electrode
WO2019093820A1 (en) Negative electrode active material, negative electrode comprising same negative electrode active material, and secondary battery comprising same negative electrode
WO2019212321A1 (en) Method for cleaning positive electrode active material, positive electrode active material manufacturing method comprising same, and positive electrode active material manufactured by same
WO2019083332A2 (en) Silicon-carbon composite and lithium secondary battery comprising same
WO2019078688A2 (en) Lithium secondary battery positive electrode active material, method for preparing same, and lithium secondary battery positive electrode and lithium secondary battery comprising same
WO2022055309A1 (en) Negative electrode active material, negative electrode comprising negative electrode active material, and secondary battery comprising negative electrode
WO2020149681A1 (en) Anode and secondary battery comprising anode
WO2019050216A2 (en) Anode active material, anode comprising same anode active material, and secondary battery comprising same anode
WO2019147084A1 (en) Method for manufacturing lithium secondary battery anode
WO2014061973A1 (en) Method for preparing silicon oxide
WO2020149618A1 (en) Method for preparing negative electrode active material
WO2020153701A1 (en) Method for producing positive electrode active material for secondary batteries

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18867387

Country of ref document: EP

Kind code of ref document: A2

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18867387

Country of ref document: EP

Kind code of ref document: A2