WO2020175782A1 - 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지 - Google Patents

양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지 Download PDF

Info

Publication number
WO2020175782A1
WO2020175782A1 PCT/KR2019/018588 KR2019018588W WO2020175782A1 WO 2020175782 A1 WO2020175782 A1 WO 2020175782A1 KR 2019018588 W KR2019018588 W KR 2019018588W WO 2020175782 A1 WO2020175782 A1 WO 2020175782A1
Authority
WO
WIPO (PCT)
Prior art keywords
active material
positive electrode
electrode active
region
transition metal
Prior art date
Application number
PCT/KR2019/018588
Other languages
English (en)
French (fr)
Inventor
서민호
김지영
Original Assignee
주식회사 에스엠랩
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 에스엠랩 filed Critical 주식회사 에스엠랩
Priority to JP2021548277A priority Critical patent/JP7258373B6/ja
Priority to CN201980091469.1A priority patent/CN113412548A/zh
Priority to US17/425,531 priority patent/US20220190316A1/en
Priority to EP19916791.7A priority patent/EP3933983A4/en
Priority claimed from KR1020190176119A external-priority patent/KR102159701B1/ko
Publication of WO2020175782A1 publication Critical patent/WO2020175782A1/ko

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00—Compounds of nickel
    • C01G53/40—Nickelates
    • C01G53/42—Nickelates containing alkali metals, e.g. LiNiO2
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00—Compounds of nickel
    • C01G53/40—Nickelates
    • C01G53/42—Nickelates containing alkali metals, e.g. LiNiO2
    • C01G53/44—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
    • C01G53/50—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese of the type [MnO2]n-, e.g. Li(NixMn1-x)O2, Li(MyNixMn1-x-y)O2
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0471—Processes of manufacture in general involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/51—Particles with a specific particle size distribution
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • cathode active material cathode active material, method for manufacturing the same, and lithium secondary battery including anode comprising the same
  • the present invention provides funding from the Ministry of Trade, Industry and Energy under the title of "Development of high strength/long life/high stability Ni-rich NCA (> 210mAh/g, @4.3V) anode material for medium and large lithium secondary batteries” It was accepted.
  • Ni-based cathode active materials are transition metals synthesized by coprecipitation.
  • the compound precursor is mixed with a lithium source and then synthesized in a solid state.
  • the Ni-based anode material synthesized in this way exists in the form of secondary particles in which small primary particles are aggregated, and is fine inside the secondary particles during a long period of medium/discharge. There is a problem that micro-cracking occurs.
  • Micro-cracking causes a side reaction of the electrolyte with the new interface of the positive electrode active material, and as a result, battery performance such as deterioration of stability due to gas generation and degradation of battery performance due to depletion of the electrolyte.
  • an increase in electrode density (>3.6g/cc) is required to achieve high energy density, which causes the collapse of secondary particles, causing electrolyte depletion due to side reactions with the electrolyte, resulting in initial lifespan.
  • the Ni-based cathode active material in the form of secondary particles synthesized by the conventional co-precipitation method cannot achieve high energy density.
  • a positive electrode active material with improved high energy density and long life characteristics in which unstable ions are stabilized, even though it does not contain 00 ions in the single crystal type positive electrode active material as described above.
  • the first region contains an element other than the (3 ⁇ 4 element
  • the second region includes a 3 ⁇ 4 element
  • the second region includes an abundance multiple region in which the concentration of 3 ⁇ 4 atom changes, and a positive electrode active material is provided.
  • part of 1 is replaced with, (elements other than 3 ⁇ 4
  • a lithium secondary battery including a positive electrode; a negative electrode; and an electrolyte; including the above-described positive electrode active material.
  • the positive electrode active material according to one side (even though it does not contain 3 ⁇ 4, part of 1 is replaced with Na element, and (the first region containing elements other than the 3 ⁇ 4 element and By including a second region containing an element, and the second region including a concentration gradient region in which the concentration of 3 ⁇ 4 atom changes, unstable cations present in the anode active material are stabilized, and the crystal structure is stabilized, Lithium secondary batteries including this have high energy density and long life characteristics.
  • Figure 1 is a SEM photograph of the positive electrode active material of Example 1 and Comparative Example 1, and Figure 1 (ratio is a graph showing the particle size distribution of the positive electrode active material of Example 1 and Comparative Example 1).
  • FIG. 2 is an SEM photograph of the positive electrode active material of Example 2 and Comparative Example 8, and FIG. 2 (ratio is a graph showing the particle size distribution of the positive electrode active material of Example 2 and Comparative Example 8).
  • 3 is a high resolution transmission electron microscopy (HR-TEM) photograph of the positive electrode active material of Comparative Example 1.
  • Figure 4 is a high-resolution transmission electron microscope of the positive electrode active material of Example 1 (high resolution
  • Figure 5 is a high-resolution transmission electron microscope of the positive electrode active material of Comparative Example 8 (high resolution
  • Figure 6 is a high-resolution transmission electron microscope of the positive electrode active material of Example 2 (high resolution
  • Fig. 7 is a life maintenance ratio for the half cells of Example 3 and Comparative Examples 15 to 18
  • Fig. 8 is a life-sustaining ratio for the half cells of Example 3 and Comparative Examples 19 to 21
  • Fig. 9 is a life-sustaining ratio for the half cells of Example 4 and Comparative Examples 22 to 25
  • Fig. W shows the life-sustaining ratio for the half cells of Example 4 and Comparative Examples 26 to 28
  • Fig. 11 is a schematic diagram of a lithium battery according to an exemplary embodiment.
  • the lithium secondary battery including the included anode will be described in more detail.
  • the positive electrode active material according to one side is partially substituted with Na, and the first region and
  • the first region contains an element other than the (3 ⁇ 4 element, and the second region Element, and the second region is
  • It may contain lithium transition metal oxide particles that include an agglomeration multiple region in which the concentration of 00 atoms changes.
  • a layered single crystal cathode active material (3 ⁇ 4 is included in the anode active material composition in order to maintain structural stability during the charging and discharging process.
  • structural stability which increases the content of 3/4
  • the first region (because it does not include 3 ⁇ 4)
  • structural instability due to the absence of 3 ⁇ 4 is It was suppressed by substituting one or more elements and substituting some of the oxygen with 8 elements.
  • the present inventors have developed a single crystal in order to improve the structural stability of the (3 ⁇ 4-free lithium transition metal oxide particles).
  • the first region may form an interior of the lithium transition metal oxide particle, and the second region may form an outer portion of the lithium transition metal oxide particle.
  • the first area and the second area are continuous areas, and the first area is an area separated from the outside by the second area.
  • the (3 ⁇ 4 atomic concentration in the farming tool pear area, can have an agricultural tool pear that increases toward the outside.
  • the (3 ⁇ 4 atom concentration is a part adjacent to the first area It can have the minimum value at, and at the interface with the outside, for example in the first area and the farthest part.
  • the concentration of the (3 ⁇ 4 atom may be 20 mol% or less in the farming tool vessel area.
  • the farming tool ship region further includes an atom
  • the concentration of the atom can have a multiplicity of farming that decreases towards the outside.
  • concentration of atoms has the minimum value at the interface of the positive electrode active material, it is possible to prevent the capacity decrease due to side reactions of the overelectrolyte.
  • the farming tool pear area may have a thickness of 500 11111 or less.
  • the farming tool area may have a thickness of 450 11111, 400 11111, 350 11111, 300 11111, or 250 11111 or less. Since the farming tool area exists as much as the distance from the surface of the lithium transition metal oxide particle, The high capacity and long life characteristics of the positive electrode active material are achieved.
  • the first region may be represented by the following formula 1:
  • M includes at least one element selected from elements of groups 3 to 12 of the periodic table, except for Co, W, Mg, and kin;
  • the and 0 ⁇ + 2) ⁇ a can be satisfied 0.02 where, ⁇ means the element molar ratio of on the one selected from among W, Mg and II. Therefore, the Mg and The molar ratio of one or more elements selected from II may be greater than 0 and less than 0.02.
  • the first region may be represented by the following formula (2):
  • It may contain one or more selected elements.
  • the above may be 0 ⁇ £0.
  • the structural stability can be improved. 1
  • Na is substituted in the lattice space where this is located, the expansion of the crystal structure due to the repulsive force between the oxygen atoms in the delithium lithium transition metal oxide of lithium in the charged state is suppressed by the intervention of Na, which has an ionic radius larger than that of lithium.
  • the structural stability of the lithium transition metal oxide is achieved even during repeated charging.
  • (X may be 0 ⁇ ( 3 ⁇ 4 £0.), where (X denotes the denture substitution molar ratio for element M in the first region represented by Chemical Formula 2.
  • Virtual group range In the case of substitution with, structural stability of the first region is improved.If the substitution molar ratio of the compound exceeds 0.01, a decrease in structural stability due to distortion of the crystal structure is caused, and 0 3 is formed as an impurity, and electrochemical properties It can lead to deterioration.
  • (3 may be 0 ⁇ (3 ⁇ 0.005).
  • (3 means the substitution molar ratio of Mg to element M in the first region represented by Formula 2. Substitution of Mg) When the molar ratio satisfies the above range, structural expansion of the first region in the charged state can be suppressed.
  • the 7 ⁇ 0 ⁇ 7 may be ⁇ 0.005.
  • (X, (3 and 7 summation can be 0 ⁇ ( 3 ⁇ 4 +(3 ⁇ 0.02).
  • (I 3 and summation 0 ⁇ ( 3 ⁇ 4 +(3+ 7 It may be £0.016. 0 If the 3 bamboo meets the above range, the structural stability of the first region is guaranteed. If the 0 burr exceeds 0.02, an impurity phase is formed, which not only acts as a lithium delithiation resistance, but also acts as a lithium delithiation resistance. Decay of the crystal structure may occur during repeated charging.
  • Formula 2 in Formula 2 (3 and 7 may be 0 ⁇ (3 ⁇ 0.003, 0 ⁇ 7 ⁇ 0.0033 ⁇ 4, respectively.
  • & may be 0 ⁇ & ⁇ 0.()1.
  • & Means the substitution molar ratio of 3 to the 0 element in the first region represented by Formula 2.
  • this oxygen element As a part of this oxygen element is replaced by 3, the bonding strength with the transition metal increases, and the transition of the crystal structure in the first region is suppressed, and as a result, the structural stability in the first region is improved.
  • the lithium transition metal oxide may be a single particle. Accordingly, the first region and the second region do not exist separately, but exist as two regions within a single particle.
  • a single particle is a secondary particle formed by agglomeration of a plurality of particles or a plurality of particles agglomerates around the agglomerate. It is a concept that is distinguished from particles formed by coating.
  • the structure of the positive electrode active material including the lithium transition metal oxide It is possible to realize energy density.
  • breakage during rolling is suppressed, high energy density can be realized, and life deterioration due to particle breakage can be prevented.
  • the lithium transition metal oxide may have a single crystal.
  • a single crystal has a concept that is distinguished from a single particle: a single particle refers to a particle formed as a single particle regardless of the type and number of crystals inside, and a single crystal means having only one crystal within the particle.
  • the single crystal lithium transition metal oxide not only has very high structural stability, but also has better lithium ion conduction than polycrystal, and has excellent high-speed charging characteristics compared to polycrystalline active materials.
  • the positive electrode active material is a single crystal and a single particle.
  • the lithium secondary battery including the same has improved lifespan characteristics and high energy. It can have density at the same time.
  • the first region may be represented by the following Chemical Formula 3 or 4: 6] [Formula 3]
  • Chemical Formula 3 it may be 0.78 1' ⁇ 1, 0 ⁇ 2'£0.2, 0 ⁇ & ' ⁇ 0.001.
  • the first region can stabilize unstable ions existing in the first region by satisfying the above composition, and maintain high energy density and long life stability.
  • Stabilization of ions is essential, but by introducing W, Mg, and II to some of the transition metal sites in the crystal, the first region can achieve an overall charge balance.
  • Ni(P) ions Inhibits oxidation from Ni(P) ions to unstable Ni(m) or Ni(IV) ions, and unstable ?3 ⁇ 4(111) or Ni(IV) can be reduced to Ni(P).
  • transition metals The loss of conductivity due to substituting some of the heterogeneous elements W, Mg, and II was compensated for by substituting a part of 0 with 3, and the decrease of the conductivity of the teeth due to structural deformation during charge/discharge as part of was replaced with Na. By suppressing the degree, the structural stability of the first region can be obtained, thereby obtaining a positive electrode active material having a high capacity and a long life.
  • the second area may be represented by the following formula (5):
  • the second region may exist on the first region.
  • the above formula 5 can satisfy 0 ⁇ /( + 2+) £0.2.
  • it may include a tail.
  • Yes for example, can be 0£ ⁇ 0.
  • Formula 5 may satisfy 0 ⁇ / ⁇ 1+ 2+ )£0.2.
  • the average particle diameter of the lithium transition metal oxide particles (1) 5 () ) is 0.1 If it falls within the above range, the desired energy density per volume can be achieved. If the average particle diameter of the lithium transition metal oxide exceeds 20//II1, a sharp drop in charging and discharging capacity is brought, and if it is less than 0.1/ffli It is difficult to obtain the desired energy density per volume.
  • a method for preparing a cathode active material includes preparing a precursor compound in which a part of Li is substituted with Na and contains an element other than the Co element; The precursor compound is heat treated to contain Co- free) obtaining lithium transition metal oxide particles; obtaining a cathode active material precursor by mixing the Co-free lithium transition metal oxide particles and a Co element-containing compound; and sintering the cathode active material precursor to obtain a cathode active material; Include.
  • the step of preparing the precursor compound is: Li element-containing
  • a compound, a Na element-containing compound, an element-containing compound, an Mg element-containing compound, a Ti element-containing compound, an M element-containing compound, and an S element-containing compound are mixed, wherein the M element may contain a transition metal.
  • the mixing step is to mechanically mix the specific element-containing compounds.
  • the mechanical mixing is performed dry.
  • the mechanical mixing is the application of a mechanical force to pulverize and mix the substances to be mixed to form a homogeneous mixture.
  • Mechanical mixing is, for example, chemically inert beads. It can be carried out by using mixing equipment such as ball mill, planetary mill, stirred ball mill, vibrating mill, etc. that use (beads).
  • mixing equipment such as ball mill, planetary mill, stirred ball mill, vibrating mill, etc. that use (beads).
  • an alcohol such as ethanol and a high-level fatty acid such as stearic acid may be selectively added in small amounts.
  • the lithium element-containing compound may include, but is not limited to, lithium hydroxide, oxide, nitride, carbon oxide, or a combination thereof.
  • the lithium precursor may be LiOH or Li 2 C0 3 .
  • the Na element-containing compound may include, but is not limited to, a hydroxide, oxide, nitride, carbon oxide of Na, or a combination thereof.
  • a hydroxide oxide, nitride, carbon oxide of Na, or a combination thereof.
  • it may be NaOH, Na 2 C0 3 or a combination thereof.
  • the W element-containing compound may include, but is not limited to, a hydroxide, oxide, nitride, carbon oxide, or a combination thereof of W.
  • W(OH) 6 WO 2020/175782 1»(:1 ⁇ 1 ⁇ 2019/018588
  • Element-containing compounds may include, but are not limited to, hydroxides, oxides, nitrides, carbon oxides, or combinations thereof.
  • they may be Mg(OH) 2 , MgC0 3 , or combinations thereof.
  • the II element-containing compound is a hydroxide, oxide, nitride, carbon oxide of II, or
  • Combinations of these may include, but are not limited to, for example, 11(03 ⁇ 4 2 , 110 2 , or combinations thereof.
  • the compound containing the element M is (3rd group of the periodic table of elements except 3 ⁇ 4,, Mg, and Kreul
  • Hydroxide, oxide, nitride, carbonate, or a combination of one or more elements selected from Group 12 elements may be included, but are not limited thereto.
  • the 8-element-containing compound is an 8 hydroxide, oxide, nitride, carbon oxide,
  • Ammonium compounds, or combinations thereof, may be included, but are not limited thereto. For example, 3 ⁇ 4) 2 8 days.
  • the heat treatment step may include a first heat treatment step and a second heat treatment step.
  • the first heat treatment step and the second heat treatment step may be performed continuously or may have a rest period after the first heat treatment step.
  • the first heat treatment step and the second heat treatment step may be performed within the same chamber or in different chambers. Can be done in
  • the first heat treatment step may be performed at a heat treatment temperature of 800°0 to 1200°.
  • the heat treatment temperature is, for example, 850 to 1200° (:, 860° 0 to 1200° (:, 870° 0 to 1200° (:, 880° 0 to 1200° (:, 890° 0 to 1200°): ,
  • 900°0 to 1200° may be, but is not limited thereto, and includes all the ranges configured by selecting any two points within the range.
  • the heat treatment temperature may be performed at 650°0 to 850.
  • the heat treatment temperature is 680°0 to 830°(:, 690°0 to 820°(:, 700°0 to 810°(:, 650°0 to 800°(), 650°0 to 780°(), 650) °0 to 760°(), 650°0 to 740°(), 650°0 to 720°(:, or 680°0 to 720°(: may be, but not limited to, any two points within the above range Select to include all configured ranges.
  • the heat treatment time in the first heat treatment step is the second
  • the heat treatment time in the first heat treatment step may be 3 to 9 hours, 4 to 9 hours, or 5 to 8 hours, but is not limited thereto, and any two points within the above range Includes all selected ranges.
  • the heat treatment time in the second heat treatment step is 15 to 25 hours
  • the first heat treatment step may include a step of heat-treating for 3 to hours at a heat treatment temperature of 800 ° 0 to 1200 ° (:.
  • the second heat treatment step may include a step of heat treatment at a heat treatment temperature of 650°0 to 850° (:) for 15 to 23 hours.
  • the precursor compound forms a -free lithium transition metal oxide particle having a layered structure and at the same time induces growth of the grains, thereby forming a single crystal shape.
  • the second heat treatment step increases the crystallinity of the layered structure generated in the first heat treatment step by performing heat treatment at a lower temperature for a longer time than in the first heat treatment step. Through the first and second heat treatment steps, the first region is formed. Single phase, single crystal, single particle high-nickel-based cobalt-free ((3 ⁇ 4-& lithium transition metal oxide particles can be obtained.
  • the (3 ⁇ 4 element-containing compound in the step of obtaining the cathode active material precursor, may be included in the organic solvent.
  • the organic solvent may be a volatile solvent.
  • the above-mentioned organic solvent may be a volatile solvent.
  • the organic solvent can be a solvent that is volatile at temperatures below 80°0, for example methanol or ethanol.
  • the firing step is at a temperature of 500°0 to 900 ⁇ (:
  • the firing step may be carried out at a temperature of 600°0 to 900° ( : According to an embodiment, the firing step may be carried out for 1 to 6 hours. For example, the firing step may be performed for 2 to 4 hours.
  • the firing step may be carried out for 1 to 6 hours at a temperature of 500°0 to 900° (:.
  • a temperature of 500°0 to 900° By firing the cathode active material precursor at the firing temperature and time, (3 ⁇ 4 atom A positive electrode active material in which a second region including a concentration gradient region having a concentration gradient is formed can be obtained.
  • the positive electrode active material according to an embodiment of the present invention is (3 ⁇ 4-the first step of producing free lithium transition metal oxide particles; and -concentration having a (3 ⁇ 4 concentration gradient) inside the free lithium transition metal oxide particles. It is summarized as a second step of forming a second region including the gradient region.
  • the lithium transition metal oxide manufactured by the above manufacturing method is a single crystal or a single particle, and the single crystal may have a layered structure.
  • the lithium transition metal oxide may have a layered structure.
  • the average particle diameter of the transition metal oxide may be 0.1/ffli to 20/ffli.
  • transition metal oxides W, Mg and Ti elements are substituted at the M element in the structure, the S element is substituted at the 0 site, and the Na element is substituted at the Li site, thereby inhibiting the existing oxidation of Ni 2+ .
  • reduction of existing unstable Ni 3+ ions to Ni 2+ ions is induced, resulting in structural stability and high-density lithium transition metal oxide.
  • reduced Ni 2+ ions and Li + ions have ion radiuses.
  • Li/Ni disordering is promoted, and the structural stability of the crystal is achieved by filling the empty lattice with Ni ions upon Li deoxidation.
  • a positive electrode comprising the positive electrode active material described above is provided.
  • a lithium secondary battery including the anode; the cathode; and an electrolyte is provided.
  • the anode and the lithium secondary battery including the anode may be manufactured in the following manner.
  • a positive electrode active material composition in which the above-described positive electrode active material, conductive material, binder, and solvent are mixed is prepared.
  • the positive electrode active material composition is directly coated on a metal current collector to produce a positive electrode plate.
  • the active material composition is cast on a separate support, and then the film peeled from the support is placed on the metal current collector.
  • a positive electrode plate may be manufactured by lamination.
  • the positive electrode is not limited to the shapes listed above, but may be in a shape other than the above.
  • Examples of the conductive material include graphite such as natural graphite and artificial graphite; carbon black; conductive tubes such as carbon nanotubes; conductive whiskers such as fluorocarbon, zinc oxide, and potassium titanate; Conductive metal oxides such as titanium oxide; etc. may be used, but are not limited thereto, and any material that can be used as a reprint in the relevant technical field may be used.
  • the binder includes vinylidene fluoride/hexafluoropropylene copolymer, polyvinylidene fluoride (PVDF), polyacrylonitrile,
  • Polymethyl methacrylate, polytetrafluoroethylene, mixtures thereof, metal salts, or styrene butadiene rubber-based polymers may be used, but are not limited thereto, and any one that can be used as a binder in the art may be used.
  • a binder lithium salt, sodium salt, calcium salt or Na salt of the above-described polymer may be used.
  • N-methylpyrrolidone N-methylpyrrolidone, acetone, or water
  • any solvent that can be used in the relevant technical field may be used.
  • the contents of the positive electrode active material, the conductive material, the binder, and the solvent are the levels commonly used in lithium batteries. Depending on the use and configuration of the lithium battery, one or more of the above conductive material, binder, and solvent may be omitted.
  • a negative electrode active material for example, a negative electrode active material, a conductive material, a binder and a solvent are mixed
  • the composition is prepared.
  • the negative electrode active material composition is directly coated and dried on a metal current collector having a thickness of 3 ⁇ to 500 ⁇ to produce a negative electrode plate.
  • a film peeled from the support is laminated on a metal current collector, thereby manufacturing a negative electrode plate.
  • the cathode current collector is not particularly limited as long as it does not cause chemical changes in the cell and has conductivity, and for example, copper, nickel, copper surface treated with carbon may be used.
  • the cathode active material can be any material that can be used as a cathode active material for a lithium battery in the relevant technical field.
  • lithium metal lithium-alloyable metal, transition metal oxide, non-transition metal oxide and carbon-based material. It may contain one or more selected from the group consisting of.
  • Alloy (above is an alkali metal, alkaline earth metal, group 13 element, group 14 element, transition metal, rare earth element or a combination element thereof, but not), 811- ⁇ alloy (above is alkali metal, alkaline earth metal, group 13 element , Group 14 elements, transition metals, rare earth elements or their
  • the transition metal oxide is lithium titanium oxide, vanadium oxide, lithium
  • the non-transition metal oxide may be 3 ⁇ 40 2 , (3 ⁇ 4(0 ⁇ 2), etc.
  • the carbon-based material may be crystalline carbon, amorphous carbon, or a mixture thereof.
  • the crystalline carbon may be graphite such as amorphous, plate-like, lean, spherical or fibrous natural graphite or artificial graphite. 0 when 15011), meso face pitch (111680) 31 86! ⁇ )It may be carbide or fired coke.
  • the same material as that of the positive electrode active material composition may be used as the transfer material, binder and solvent.
  • the contents of the cathode active material, conductive material, binder, and solvent are the levels normally used in lithium batteries. Depending on the use and configuration of the lithium battery, one or more of the above conductive material, binder, and solvent may be omitted. 2020/175782 1»(:1 ⁇ 1 ⁇ 2019/018588
  • the above separator can be used as long as it is commonly used in a lithium battery. It can be used that has a low resistance against the movement of ions of an electrolyte and has excellent electrolyte-moisturizing ability.
  • the separator may be a single film or a multilayer film, for example, glass fiber, polyester, Teflon, polyethylene, polypropylene, polyvinylidene fluoride, polytetrafluoroethylene (1 M3 or a combination thereof), and may be in the form of a non-woven fabric or a woven fabric. Ethylene/polypropylene two-layer separator,
  • Mixed multilayer films such as polypropylene/polyethylene/polypropylene three-layer separator can be used, for example, polyethylene,
  • a rollable separator such as polypropylene is used,
  • a separator having an excellent organic electrolyte impregnation ability can be used for a lithium ion polymer battery.
  • the separator can be manufactured according to the following method.
  • a separator composition is prepared by mixing a polymer resin, a filler, and a solvent.
  • the separator composition can be directly coated and dried on an upper electrode to form a separator.
  • the separator composition is cast and dried on a support. Thereafter, the separator film peeled off from the support may be laminated on the upper portion of the electrode to form a separator.
  • the polymer resin used in the manufacture of the separator is not particularly limited, and all materials used for the bonding material of the electrode plate may be used.
  • vinylidene fluoride/hexafluoropropylene copolymer vinylidene fluoride/hexafluoropropylene copolymer
  • Polymethyl methacrylate or mixtures thereof may be used.
  • the electrolyte may be an organic electrolyte.
  • the electrolyte may be a solid.
  • it may be boron oxide, lithium oxynitride, etc., but is not limited thereto, and a solid electrolyte in the art. Anything that can be used can be used.
  • the solid electrolyte can be formed on the cathode by a method such as sputtering.
  • an organic electrolyte can be prepared by dissolving a lithium salt in an organic solvent.
  • organic solvent can be used as an organic solvent in the relevant technical field
  • cyclic carbonates such as propylene carbonate, ethylene carbonate, fluoroethylene carbonate, butylene carbonate, and vinylene carbonate; dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate , Chain carbonates such as methyl isopropyl carbonate, dipropyl carbonate, and dibutyl carbonate; methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, 1 butyrolactone Esters such as; 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran,
  • Ethers such as 1,2-dioxane and 2-methyltetrahydrofuran; nitriles such as acetonitrile; amides such as dimethylformamide, etc. These can be used alone or in combination of a plurality of them.
  • a mixed solvent of cyclic carbonate and chain carbonate can be used.
  • a gel polymer electrolyte impregnated with an electrolyte in a polymer electrolyte such as polyethylene oxide and polyacrylonitrile, or Lil, Li 3 N, Li x Ge y P z S a , Li x Ge y P z S a Inorganic solid electrolytes such as X 6 (X F, Cl, Br) can be used.
  • a polymer electrolyte such as polyethylene oxide and polyacrylonitrile, or Lil, Li 3 N, Li x Ge y P z S a , Li x Ge y P z S a
  • lithium salt can also be used as a lithium salt in the relevant technical field
  • All can be used, e.g. LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiC10 4 , LiCF 3 S0 3 , Li(CF 3 S0 2 ) 2 N, LiC 4 F 9 S0 3 , LiA10 2 , L1AICI 4 , LiN(C x F 2x+1 S0 2 )(C y F 2y+1 S0 2 ) (but is a natural number), LiCl, Lil or a mixture thereof.
  • LiPF 6 LiBF 4 , LiSbF 6 , LiAsF 6 , LiC10 4 , LiCF 3 S0 3 , Li(CF 3 S0 2 ) 2 N, LiC 4 F 9 S0 3 , LiA10 2 , L1AICI 4 , LiN(C x F 2x+1 S0 2 )(C y F 2y+1 S0 2 ) (but is a natural number), LiCl, Lil or a mixture thereof.
  • the lithium battery (1) includes a positive electrode (3), a negative electrode (2), and
  • the organic electrolyte is injected into the battery case 5 and sealed with a cap assembly 6 so that the lithium battery 1
  • the battery case 5 may be a cylinder type, a square type, a pouch type, a coin type, a thin film type, etc.
  • the lithium battery 1 may be a thin film type battery.
  • the lithium battery 1 is a lithium battery It can be an ion battery.
  • a battery structure can be formed by arranging a separator between the positive electrode and the negative electrode.
  • the battery structure After the battery structure is laminated in a bi-cell structure, it is impregnated with an organic electrolyte, and the resulting product is received in a pouch and sealed to complete a lithium ion polymer battery.
  • the battery structure is stacked in plurality to form a battery pack
  • the lithium battery can be used in electric vehicles (EV) because of its excellent lifespan and high rate characteristics.
  • EV electric vehicles
  • hybrid vehicles such as plug-in hybrid electric vehicles (PHEV).
  • PHEV plug-in hybrid electric vehicles
  • it can be used in applications where a large amount of power storage is required, e.g. electric bicycles, power tools, systems for power storage, etc.
  • Ni 0.8 Mn 0.2 (OH) 2 of 10 and 0 2 00 3 of 41.8 silver and NaOH of 0.45 silver are mechanically mixed for about 15 minutes.
  • the mixed powder is heat treated for 8 hours at 920°0 and for 20 hours at 700°0 ( 3 ⁇ 4 -free lithium transition metal oxide particles were obtained.
  • the four added to the lithium transition metal oxide particle-containing group to the costume silver cobalt acetate solution is dissolved in ethanol and stirred for 30 minutes, and the mixture solution 80. (: was allowed to stand in the evaporation of ethanol, the obtained powder
  • the positive electrode active material was obtained by firing at 800° ( :) for 3 hours.
  • the specific composition of the obtained positive electrode active material can be confirmed in Table 1.
  • Ni 0.8 Mn 0.2 (OH) 2 of 10 and 1 ⁇ of 41.8 silver (:0 3 , 3 of 0 3 , 0.24 of 110 2 of silver are mechanically mixed for about 15 minutes.
  • the mixed powder is 920°0 for 8 hours.
  • the mixed powder was heat-treated at 880°0 for 8 hours and 700°0 for 20 hours to obtain lithium transition metal oxide particles.
  • a positive electrode active material After firing for 3 hours, a positive electrode active material was obtained.
  • the specific composition of the obtained positive electrode active material can be confirmed in Table 1.
  • 0 2 00 3 , 3. 0 3 , 0.2 of MgC0 3 , 0.24 ⁇ £] 110 2 , 0.45 silver NaOH and 0.2 silver NH 4 F are mechanically mixed for about 15 minutes.
  • the mixed powder is 880°0 for 8 hours.
  • Example 231 The positive electrode active material obtained in Example 1: the conductive material: the binder in a weight ratio of 94:3:3
  • the mixture was mixed to prepare a slurry.
  • carbon black was used as the conductive material
  • polyvinylidene fluoride (1 ⁇ (s)) was used as the binder.
  • the slurry was evenly applied to a new current collector and dried for 2 hours at 1 o (:) to produce a positive electrode.
  • the loading level of the electrode plate was 11.0.
  • the electrode density was 3.6 silver/ ⁇ : ⁇ :.
  • the prepared positive electrode was used as a working electrode, and lithium foil was used as a counter electrode.
  • a half cell was manufactured in the same manner as in Example 3, except that the positive electrode active material obtained in Example 2 was used instead of the positive electrode active material obtained in Example 1, respectively.
  • a half cell was manufactured in the same manner as in Example 3, except that the positive electrode active material was used respectively. 2020/175782 1»(:1/10 ⁇ 019/018588
  • Example 1 and Comparative Example 1 The positive electrode active material synthesized in Example 1 and Comparative Example 1, and Example 2 and Comparative Example 8 was subjected to inductively coupled plasma (ICP) analysis using a 700-ES (Varian) equipment, and the results are shown in the following table. It is listed in 2 and 3 respectively.
  • ICP inductively coupled plasma
  • the transition metal in the positive electrode active material for example, and Mn
  • the concentration remains substantially constant toward the surface and center of the positive electrode active material.
  • the concentration gradient layer is about 500 11111.
  • cobalt ions among the transition metals contribute to the structural stability of the positive electrode active material having a layered structure compared to nickel ions.
  • the concentration of the transition metal, for example, and god, in the positive electrode active material is substantially constant in the direction of the surface and the center of the positive electrode active material.
  • the concentration gradient layer is about 500 11111.
  • cobalt ions among the transition metals contribute to the structural stability of the positive electrode active material having a layered structure compared to nickel ions. 2020/175782 1»(:1 ⁇ 1 ⁇ 2019/018588
  • Example 3 in which the positive electrode active material including the second region including the agricultural tool pear region was applied, exhibited a high lifespan retention rate of about 7% in 100 cycles. This is because the positive electrode active material used in Example 3 did not contain (3 ⁇ 4). Nevertheless, the introduction of Na element to the lithium site in the structure inhibits the spontaneous reduction of nickel ions.
  • Electrochemically inactive win-win is inhibited.
  • the introduction of elements increases structural stability by increasing the zero of ions in the structure, and increases the bonding strength between the transition metal and oxygen to suppress the release of oxygen in the structure during electrochemical evaluation, thereby suppressing side reactions with the electrolyte.
  • the three elements substituted at the oxygen site have high electronegativity compared to oxygen, increasing the bonding strength between the transition metal and oxygen, and at the same time improving the conductivity of the active material.
  • Example 3 is Comparative Example 16,
  • Example 4 As the second region including the concentration gradient region was introduced, the lifespan was improved by about 9% in 0 cycles compared to Comparative Example 22 that did not include the concentration gradient region. Comparative Example 23 in which elements were introduced, Comparative Example 24 in which ⁇ , 11 were introduced, Compared to Comparative Example 25 in which the element was introduced

Abstract

Li의 일부가 Na으로 치환되고, 제1영역 및 제2영역을 포함하는 리튬 전이금속 산화물 입자로서, 상기 제1영역은 Co 원소 이외의 원소를 포함하고, 상기 제2영역은 Co 원소를 포함하고, 상기 제2영역은 Co 원자의 농도가 변화하는 농도구배영역을 포함하는 리튬 전이금속 산화물 입자를 포함하는, 양극활물질, 이의 제조방법, 이를 포함하는 양극을 구비한 리튬 이차전지에 관한 것이다.

Description

명세서
발명의 명칭:양극활물질，이의제조방법 및이를포함하는양극을 포함한리튬이차전지
기술분야
[1] 신규조성의양극활물질,이를포함하는양극및상기양극을포함하는리튬 이차전지에관한것이다.
[2] 본발명은 "중대형리튬이차전지용고강도/장수명/고안정성 Ni-rich NCA(> 210mAh/g, @4.3V)양극소재개발”이라는제목의과제고유번호 P0009541의 산업통상자원부의자금을지원받아이루어졌다.
배경기술
[3] 리튬이차전지는 1991년 Sony社에의해상용화된이후 mobile IT제품과같은 소형가전으로부터,중대형전기자동차및에너지저장시스템까지다양한 분야에서수요가급증하고있다.특히,중대형전기자동차및에너지저장 시스템을위해서는저가형고에너지양극소재가필수적인데,현재상용화된 양극활물질인단결정형 LiCo02 (LCO)의주원료인코발트는고가이다.
[4] 최근에는,제조단가를낮추면서용량을극대화하기위하여, 의몰비율이 50몰%이상으로포함한고-니켈계양극활물질이주목받고있다.이러한 Ni계 양극활물질은공침법으로합성한전이금속화합물전구체를리튬소스와 혼합한후고상으로합성하여제조된다.그러나,이렇게합성된 Ni계양극 소재는작은일차입자들이뭉쳐져있는이차입자형태로존재하여,장기간의 중/방전과정에서이차입자내부에미세균열 (micro-crack)이발생된다는 문제점이존재한다.미세균열은양극활물질의새로운계면과전해액의 부반응을유발하고,그결과가스발생에따른안정성저하및전해액고갈로 인한전지성능저하와같은전지성능열화가유발된다.또한,고에너지밀도 구현을위해전극밀도의증가 (>3.6g/cc)를필요로하는데,이는이차입자의 붕괴를유발해전해액과의부반응으로인한전해액고갈을유발하여초기수명 급락을유발한다.결국,기존의공침법으로합성한이차입자형태의 Ni계 양극활물질은고에너지밀도를구현할수없음을의미한다.
[5] 전술한이차입자형태의 Ni계양극활물질의문제점을해결하고자,최근에 단입자형 Ni계양극활물질에대한연구가이루어지고있다.단결정형 Ni계 양극활물질은 3.6g/cc초과의전극밀도에서도,입자의붕괴가발생하지않아 뛰어난전기화학성능을구현할수있다.하지만,이러한단결정형 Ni계 양극활물질은전기화학평가시，불안정한 Ni3+, Ni4+이온으로인해구조적 및/또는열적불안정성으로인해배터리안정성이저하된다는문제점이 제기되었다.따라서 ,고에너지리튬이차전지개발을위해서 ,단결정형 Ni계 양극활물질의불안정한 Ni이온을안정화시키는기술에대한요구가여전히 2020/175782 1»（：1^1{2019/018588
2 존재한다.
[6] 한편,최근에는코발트의가격이상승함에따라양극활물질의가격이상승하고 있다.이에,코발트원소를함유하지않는저가형양극활물질의개발을위한 연구가진행되고있으나,코발트원소를포함하지않는경우상의안정성이 저하된다는문제점이발생하였다.
[7] 따라서,코발트원소를포함하지않으면서도,고에너지밀도를갖고,높은
전극밀도를갖는양극활물질의개발에대한요구가상당하다.
발명의상세한설명
기술적과제
[8] 일측면에따르면,전술한바와같은단결정형 계양극활물질중에 00이온을 포함하지않음에도불구하고,불안정한 이온이안정화된고에너지밀도및 장수명특성이향상된양극활물질을제공하는것이다.
과제해결수단
[9] 일측면에따라, 1 의일부가 으로치환되고,제 1영역및제 2영역을포함하는 리튬전이금속산화물입자로서 ,상기제 1영역은 (¾원소이외의원소를 포함하고,상기제 2영역은 (¾원소를포함하고,상기제 2영역은 (¾원자의 농도가변화하는농도구배영역을포함하는,양극활물질이제공된다.
[1이 다른측면에따라, 1 의일부가 으로치환되고, (¾원소이외의원소를
포함하는전구체화합물을준비하는단계;상기전구체화합물을열처리하여 함유 ((¾-:6 )리튬전이금속산화물입자를얻는단계 ;상기 (¾-:6 리튬 전이금속산화물입자, (¾원소함유화합물을혼합하여양극활물질전구체를 얻는단계;및상기양극활물질전구체를소성하여양극활물질을얻는단계를 포함하는양극활물질의제조방법이제공된다.
[11] 또다른측면에따라,전술한양극활물질을포함하는양극;음극;및전해질;을 포함하는리튬이차전지가제공된다.
발명의효과
[12] 일측면에따른양극활물질은 (¾를포함하지않음에도불구하고, 1 의일부가 Na원소로치환되고, (¾원소이외의원소를포함하는제 1영역및
Figure imgf000003_0001
원소를 포함하는제 2영역을포함하고,상기제 2영역이 (¾원자의농도가변화하는 농도구배영역을포함하는것에의하여 ,양극활물질에존재하는불안정한 양이온이안정화되고,결정구조가안정화되어,이를포함한리튬이차전지는 고에너지밀도및장수명특성을갖는다.
도면의간단한설명
[13] 도 1知)는실시예 1및비교예 1의양극활물질에대한 SEM사진이고,도 1(비는 실시예 1및비교예 1의양극활물질의입도분포를보여주는그래프이다.
[14] 도 2知)는실시예 2및비교예 8의양극활물질에대한 SEM사진이고,도 2(비는 실시예 2및비교예 8의양극활물질의입도분포를보여주는그래프이다. [15] 도 3은비교예 1의양극활물질의고해상도투과전자현미경 (high resolution transmission electron microscopy (HR-TEM))사진이다.
[16] 도 4는실시예 1의양극활물질의고해상도투과전자현미경 (high resolution
transmission electron microscopy (HR-TEM))사진이다.
[17] 도 5은비교예 8의양극활물질의고해상도투과전자현미경 (high resolution
transmission electron microscopy (HR-TEM))사진이다.
[18] 도 6는실시예 2의양극활물질의고해상도투과전자현미경 (high resolution
transmission electron microscopy (HR-TEM))사진이다.
[19] 도 7은실시예 3및비교예 15내지 18의하프셀에대한수명유지율
그래프이다.
[2이 도 8는실시예 3및비교예 19내지 21의하프셀에대한수명유지율
그래프이다.
[21] 도 9는실시예 4및비교예 22내지 25의하프셀에대한수명유지율
그래프이다.
[22] 도 W은실시예 4및비교예 26내지 28의하프셀에대한수명유지율
그래프이다.
[23] 도 11는예시적인구현예에따른리튬전지의모식도이다.
[24]
[25] ＜도면의주요부분에대한부호의설명＞
[26] 1:리튬전지 2:음극
[27] 3:양극 4:세퍼레이터
[28] 5:전지케이스 6:캡어셈블리
[29]
발명의실시를위한형태
[30] 이하에서설명되는본창의적사상 (present inventive concept)은다양한변환을 가할수있고여러가지실시예를가질수있는바,특정실시예들을도면에 예시하고,상세한설명에상세하게설명한다.그러나,이는본창의적사상을 특정한실시형태에대해한정하려는것이아니며 ,본창의적사상의기술 범위에포함되는모든변환,균등물또는대체물을포함하는것으로이해되어야 한다.
[31] 이하에서사용되는용어는단지특정한실시예를설명하기위해사용된
것으로,본창의적사상을한정하려는의도가아니다.단수의표현은문맥상 명백하게다르게뜻하지않는한,복수의표현을포함한다.이하에서, "포함한다” 또는 "가지다”등의용어는명세서상에기재된특징,숫자,단계,동작,구성요소, 부품,성분,재료또는이들을조합한것이존재함을나타내려는것이지,하나 또는그이상의다른특징들이나,숫자,단계 ,동작,구성요소,부품,성분,재료 또는이들을조합한것들의존재또는부가가능성을미리배제하지않는것으로 2020/175782 1»（：1^1{2019/018588
4 이해되어야한다.이하에서사용되는 " 는상황에따라 "및”으로해석될수도 있고 "또는’’으로해석될수도있다.
[32] 도면에서 여러층및 영역을명확하게표현하기위하여두께를확대하거나 축소하여 나타내었다.명세서 전체를통하여유사한부분에 대해서는동일한 도면부호를붙였다.명세서 전체에서층,막,영역,판등의부분이다른부분 "상에”또는 "위에”있다고할때,이는다른부분의 바로위에 있는경우뿐만 아니라그중간에또다른부분이 있는경우도포함한다.명세서 전체에서제 1, 제 2등의용어는다양한구성요소들을설명하는데사용될수있지만,구성 요소들은용어들에의하여 한정되어서는안된다.용어들은하나의구성요소를 다른구성요소로부터구별하는목적으로만사용된다.
[33]
[34] 이하에서 예시적인구현예들에따른양극활물질,이의제조방법 및이를
포함하는양극을포함한리튬이차전지에관하여 더욱상세히 설명한다.
[35] 일측면에 따른양극활물질은 의 일부가 Na으로치환되고,제 1영역 및
제 2영역을포함하는리튬전이금속산화물입자로서 ,상기제 1영역은 (¾원소 이외의 원소를포함하고,상기 제 2영역은
Figure imgf000005_0001
원소를포함하고,상기제 2영역은
00원자의농도가변화하는농도구배영역을포함하는리튬전이금속산화물 입자를포함할수있다.
[36] 통상적으로층상형 단결정 양극활물질은충방전과정에서구조적 안정성을 유지하기 위하여 (¾를양극활물질조성내에포함한다.하지만 (¾의높은 가격으로인해,구조적 안정성을위하여 (¾의함량을높이는경우제조비용이 현저히증가하여산업적 적용은어려운실정이다.이에 , (¾를포함하지 않는 고용량의 양극활물질에관한연구가지속적으로이루어지고있으나,충방전시 상전환에 의한비가역용량이 현저히증가하는한계점이존재한다.
[37] 본발명의 발명자는 (¾를포함하지 않음에도불구하고,고-니켈계리튬
전이금속산화물의 중일부를 Na으로치환하고, (¾를제외한원소를 포함하는제 1영역 및제 1영역을둘러싸면서 (¾원소를포함하는제 2영역을 포함하고,상기 제 2영역이 (¾원자의농도가변화하는농도구배영역을포함하는 것에 의하여충방전에도비가역상의발생이 억제되어구조적 안정성을갖는 양극활물질을제조하였다.
[38] 후술하겠지만,제 1영역은 (¾를포함하지 않는영역이므로,충방전과정에서 층상형구조가암염구조로변형될우려가있으나, (¾의 비함유에따른구조적 불안정성은 , 및 II중 1종이상의 원소를치환하고,산소중일부를 8 원소로치환하는것에 의하여 억제되었다.더 나아가,본발명자는 (¾ -비함유 리튬전이금속산화물입자의구조적 안정성을향상시키기 위하여,단결정
-비함유양극활물질의표면에 (¾농도구배 영역을포함하는제 2영역을 도입하였으며，이러한제 2영역은제 1영역이 전해액과직접적으로접촉하는 것을막을뿐만아니라,양극활물질의 전기화학적 반응과정에상안정성에 2020/175782 1»（：1^1{2019/018588
5 기여하여 ,구조적 안정성을향상시킨다.
[39] 일구현예에 따르면,상기상기 제 1영역은상기 리튬전이금속산화물입자의 내부를형성하고,상기제 2영역은상기 리튬전이금속산화물입자의외곽부를 형성할수있다.예를들어,제 1영역과제 2영역은연속적인영역이며,제 1영역은 제 2영역에 의하여외부와분리된영역이다.
[4이 일구현예에 따르면,상기농도구배영역에서상기（¾원자의농도는외부측을 향하여증가하는농도구배를가질수있다.예를들어,상기（¾원자의농도는 제 1영역과인접한부분에서 최소값을가질수있고,외부와접하는계면에서 , 예를들어제 1영역과가장먼부분에서최대값을가질수있다.
[41] 일구현예에 따르면,상기농도구배영역에서상기（¾원자의농도는 20몰% 이하일수있다.
[42] 일구현예에 따르면,상기농도구배영역은 원자를더포함하고,상기
원자의농도는외부측을향해감소하는농도구배를가질수있다. 원자의 농도가양극활물질계면에서 최소값을가짐에 따라, 과전해액의부반응에 의한용량저하를방지할수있다.
[43] 일구현예에 따르면,상기농도구배영역은 500 11111이하의두께를가질수있다. 예를들어 ,상기농도구배영역은 450 11111, 400 11111, 350 11111, 300 11111또는 250 11111 이하의두께를가질수있다.상기농도구배 영역이상기 리튬전이금속산화물 입자표면으로부터상기 거리만큼존재하는것에의하여,양극활물질의고용량 및장수명특성이 달성된다.
[44] 일구현예에 따르면,상기제 1영역은하기화학식 1로표시될수있다:
[45] [화학식 1]
[46] - ’02浴
[47] 상기화학식 1중,
[48] M은Co, W, Mg및꾜를제외한원소주기율표제 3족내지제 12족원소로부터 선택된 1종이상의 원소를포함하고;
[49] Mg및 II중에서선택된 1종이상의원소를포함하고,
[50] 0＜＜0.01, 0에, 0에, 0＜1＜■이다.
[51] 일구현예에 따르면,상기 및 는 0＜ +2）＜0.02를만족할수있다.여기서 , å는 W, Mg및 II중에서선택된 1종이상의 원소의몰비를의미한다.따라서,상기 Mg및 II중에서선택된 1종이상의 원소의몰비는 0초과 0.02이하일수있다.
[52] 예를들어,상기 및 는 0＜2分+2）＜0.016일수있다.
[53] 일구현예에 따르면,상기제 1영역은하기화학식 2로표시될수있다:
[54] [화학식 2]
Figure imgf000006_0001
[56] 상기화학식 2중,
Figure imgf000006_0002
2020/175782 1»（：1^1{2019/018588
6
[58] 0< <0.01, 0<(¾<0.01, 0<(3<0.005, 0
[59] 일구현예에따르면,상기화학식
Figure imgf000007_0001
선택된 1종이상의원소를포함할수있다.
[6이 예를들어 ,상기화학식
Figure imgf000007_0002
원소를포함할수있다.
[61] 일구현예에따르면,상기 는 0< £0.이일수있다.여기서, 는화학식 2로 표시되는제 1영역에서니에대한 Na의치환몰비율을의미한다.상기화학식 2로 표시되는제 1영역은니의일부가 Na으로치환됨에따라,구조적안정성이 향상될수있다. 1 이위치하는격자공간에 Na이치환되는경우리튬에비하여 이온반경이큰 Na의개입에의하여충전상태에서리튬의탈리시리튬전이금속 산화물내의산소원자들간반발력에의한결정구조의팽창이억제되고,그 결과반복적충전시에도리튬전이금속산화물의구조적안정성이달성된다.
[62] 일구현예에따르면,상기 (X는 0<(¾£0.이일수있다.여기서 (X는화학식 2로 표시되는제 1영역에서 M원소에대한 의치환몰비율을의미한다. 가상기 범위로치환되는경우에제 1영역의구조적안정성이향상된다. 의치환 몰비율이 0.01을초과하는경우,결정구조상의비틀림에따른구조적안정성의 저하가유발되고,불순물로서 03이형성되어,전기화학적특성의저하가 초래될수있다.
[63] 일구현예에따르면,상기 (3는 0< (3 <0.005일수있다.여기서 (3는화학식 2로 표시되는제 1영역에서 M원소에대한 Mg의치환몰비율을의미한다. Mg의치환 몰비율이상기범위를만족하는경우충전상태에서제 1영역의구조적팽창이 억제될수있다.
[64] 일구현예에따르면,상기 7 ^ 0< 7 <0.005일수있다.여기서 는화학식 2로 표시되는제 1영역에서 M원소에대한 II의치환몰비율을의미한다. II의치환 몰비율이상기범위를만족하는경우충전상태에서제 1영역의구조적팽창이 억제될수있다.
[65] 상기제 1영역에서 , Mg, II가상기몰비율로치환되는경우,충전상태에서 리튬탈리시에도산소들간의상호작용에의한결정의구조적팽창억제에 의하여,구조적안정성이향상되어수명특성이향상된다.
[66] 일구현예에따르면, (X, (3및 7의합은 0<(¾+(3竹<0.02일수있다.예를들어 , (나 3 및 의합은 0<(¾+(3+7£0.016일수있다. 0버 3竹가상기범위를만족하는경우에 제 1영역의구조적안정성이보장된다. 0버 가 0.02를초과하는경우불순물 상이형성되고,이는리튬탈리시저항으로작용할뿐만아니라,반복적 충전시에결정구조의붕괴가야기될수있다.
[67] 일구현예에따르면,상기화학식 2에서 (3및 7는각각 0<(3<0.003, 0<7<0.003¾ 수있다.
[68] 예를들어,상기화학식 2
Figure imgf000007_0003
수있다. (3=7 ¾경우,예를들어 Mg및 II의 몰비율이동일한경우)에충전및방전시제 1영역내의전하균형이이루어져 2020/175782 1»（：1^1{2019/018588
7 결정구조의붕괴가억제되어구조적 안정성이 향상되고,그결과수명특성이 향상된다.
[69] 일구현예에 따르면,상기 &는 0<&<0.()1일수있다.예를들어, 0¾£0.005, 0<&<0.003또는 0<&<0.0()1일수있다.여기서, &는화학식 2로표시되는 제 1영역에서 0원소에 대한 3의치환몰비율을의미한다.
이 산소원소의 일부가 3로치환됨에따라전이금속과의결합력이증가하여 , 제 1영역에서 결정구조의 전이가억제되고,그결과제 1영역에서의구조적 안정성이 향상된다.
1] 한편, 8의치환몰비율이 0.()1을초과하는경우 8음이온의 반발력으로인해 결정구조가불안정해져서오히려수명특성이 저하된다.
2] 일구현예에 따르면,상기 리튬전이금속산화물은단일입자일수있다. 따라서,제 1영역 및제 2영역이분리되어존재하지 않고,단일입자내에 2개의 영역으로존재하는것이다.또한,단일입자는복수의 입자가응집되어 형성된 이차입자또는복수의 입자가응집되고응집체의둘레가코팅되어 형성된 입자와는구분되는개념이다.상기 리튬전이금속산화물이단일입자의 형태를 가짐으로써,높은전극밀도에서도입자의부서짐을방지할수있다.따라서, 리튬전이금속산화물을포함하는양극활물질의고에너지 밀도의구현이 가능해진다.또한,복수의 단일입자가응집된이차입자에비하여 압연시에 부서짐이 억제되어고에너지 밀도의구현이 가능하며,입자의부서짐에 따른 수명 열화도방지할수있다.
3] 일구현예에 따르면,상기 리튬전이금속산화물은단결정을가질수있다. 단결정은단일입자와는구별되는개념을갖는다.단일입자는내부에결정의 유형과개수에상관없이하나의 입자로형성된입자를지칭하는것이며, 단결정은입자내에 단하나의 결정을갖는것을의미한다.이러한단결정의 리튬전이금속산화물은구조적 안정성이 매우높을뿐만아니라,다결정에비해 리튬이온전도가용이하여,다결정의활물질에 비하여고속충전특성이 우수하다.
4] 일구현예에 따르면,상기 양극활물질은단결정 및단일입자이다.단결정 및 단일입자로형성됨으로써,구조적으로안정하고고밀도의 전극의구현이 가능하여,이를포함한리튬이차전지가향상된수명특성 및고에너지 밀도를 동시에 가질수있다.
5] 일구현예에 따르면,상기제 1영역은하기화학식 3또는 4로표시될수있다: 6] [화학식 3]
[77] 니 Nax.NiyrMny2.Wa.Mgp.lv) ¾
8] [화학식 4]
[79]
Figure imgf000008_0001
[8이 상기화학식 3에서,
[81] 0<^<0.01, 0<^<0.01, 0<(3'<0.005, 0< <0.005, 0<^<0.01, 0<於'+(3'+ <0.02, 2020/175782 1»（：1^1{2019/018588
8
0.68< '<1,어守 , + 十 + (3'+ =1이고,
[82] 상기화학식 4에서,
Figure imgf000009_0001
[84] 예를들어,상기 화학식 3에서, 0<(3'£0.003, 0<7'<0.003, 0<끄'+(3'+ <0.016이고, 상기 화학식 4에서, 0< 03, 0</ 03, 0< +(3"+'/,<0.016일수있다.
[85] 예를들어,상기 화학식 3에서, 0.78 1’<1, 0今2’£0.2, 0<&'<0.001일수있다.
[86] 예를들어,상기 화학식 4에서, 0.88£ ”<1, 0今2”<0.1, 0<^'<0.001일수있다.
[87] 상기제 1영역은상기조성을만족하는것에 의하여제 1영역 내부에존재하는 불안정한 이온을안정화시킬수있으며 ,고에너지밀도및장수명 안정성을 보유할수있다.
[88] 일반적인코발트-
Figure imgf000009_0002
양극활물질의 경우불안정한
이온의 안정화가필수적인데,결정 내의 전이금속자리중일부에 W, Mg및 II가 도입됨으로써,제 1영역이 전체적으로전하균형을이룰수있게되어
Ni(P)이온으로부터불안정한 Ni(m)또는 Ni(IV)이온으로의산화를억제하고, 불안정한 ?¾(111)또는 Ni(IV)은 Ni(P)로환원될수있다.한편,전이금속의 일부를 이종원소인 W, Mg및 II로치환함에따른전도도의손실은 0의 일부를 3로 치환하는것에의하여보상되었고, 의 일부를 Na으로치환함에따라 충방전시의구조적 변형에 의한니의 전도도저하도억제함으로써,제 1영역의 구조적 안정성을얻음으로써,고용량및장수명의 양극활물질을얻을수있다.
[89] 일구현예에 따르면,상기제 2영역은하기화학식 5로표시될수있다:
[9이 [화학식 5]
[91] 此 네。0 1 0241¾
[92] 상기화학식 5중,
[93]
Figure imgf000009_0003
제외한원소주기율표제 3족내지제 12족원소로부터 선택된 1종이상의 원소를포함하고;
[94] 중에서선택된 1종이상의원소를포함하고,
[95]
Figure imgf000009_0004
1, 0今2<1, 0< <1, 0 1<0.()1이다.
[96] 일구현예에 따르면,상기제 2영역은제 1영역상에존재할수있다.
[97] 일구현예에 따르면,상기화학식 5는 0< /( + 2+ )£0.2를만족할수있다.
[98] 일구현예에 따르면, 은 , ,신, ¼  ¾：8및 I5중에서선택된 1종
이상의 원소를포함할수있다.예를들어, 은 , ,신, ¾：8및모중에서 선택된 1종이상의 원소를포함할수있다.
[99] 일구현예에 따르면, 끄를포함할수있다.
[10이 일구현예에 따르면,
Figure imgf000009_0005
있다.예를들어, 은 0£ <0.이일수 있다.
[101] 일구현예에 따르면,상기화학식 5는 0 < /分1+ 2+ )£0.2를만족할수있다.
[102] 일구현예에 따르면,상기 리튬전이금속산화물입자의평균입경 (1)5())은 0.1 상기범위에속하는경우,소망하는체적당에너지밀도를구현할수있다.상기 리튬전이금속산화물의평균입경이 20//II1을초과하는경우충방전용량의 급격한저하를가져오게되고, 0.1/ffli이하인경우원하는체적당에너지밀도를 얻기어렵다.
[103]
[104] 이하,일측면에따른양극활물질의제조방법에대하여상세히설명한다.
[105] 일측면에따른양극활물질의제조방법은 Li의일부가 Na으로치환되고, Co 원소이외의원소를포함하는전구체화합물을준비하는단계;상기전구체 화합물을열처리하여 Co-미함유 (Co-free)리튬전이금속산화물입자를얻는 단계 ;상기 Co-free리튬전이금속산화물입자, Co원소함유화합물을혼합하여 양극활물질전구체를얻는단계;및상기양극활물질전구체를소성하여 양극활물질을얻는단계;를포함한다.
[106] 일구현예에따르면,상기전구체화합물을준비하는단계는: Li원소함유
화합물, Na원소함유화합물, 원소함유화합물, Mg원소함유화합물, Ti원소 함유화합물, M원소함유화합물및 S원소함유화합물을혼합하는단계를 포함하고,상기 M원소는전이금속을포함할수있다.
[107] 상기혼합단계는상기특정원소함유화합물들을기계적혼합하는것을
포함할수있다.상기기계적혼합은건식으로수행된다.상기기계적혼합은 기계적힘을가하여혼합하고자하는물질들을분쇄및혼합하여균일한 혼합물을형성하는것이다.기계적혼합은예를들어 ,화학적으로불활성인 비드 (beads)를이용하는볼밀 (ball mill),유성밀 (planetary mill),교반볼밀 (stirred ball mill),진동밀 (vibrating mill)등과같은혼합장치를이용하여수행될수있다. 이때,혼합효과를극대화하기위하여,에탄올과같은알코올,스테아르산과 같은고급지방산을선택적으로소량첨가할수있다.
[108] 상기기계적혼합은산화분위기에서수행되는데,이는전이금속공급원 (예, Ni 화합물)에서전이금속의환원을막아서,활물질의구조적안정성을구현하기 위한것이다.
[109] 상기리튬원소함유화합물은리튬수산화물,산화물,질화물,탄산화물,또는 이들의조합을포함할수있으나,이에한정되지않는다.예를들어,리튬 전구체는 LiOH또는 Li2C03일수있다.
[110] 상기 Na원소함유화합물은 Na의수산화물,산화물,질화물,탄산화물,또는 이들의조합을포함할수있으나,이에한정되지않는다.예를들어, NaOH, Na2 C03또는이들의조합일수있다.
[111] 상기 W원소함유화합물은 W의수산화물,산화물,질화물,탄산화물,또는 이들의조합을포함할수있으나,이에한정되지않는다.예를들어, W(OH)6, WO 2020/175782 1»（：1^1{2019/018588
10
3또는이들의조합일수있다.
[112] 상기
Figure imgf000011_0001
원소함유화합물은 수산화물,산화물,질화물,탄산화물,또는 이들의조합을포함할수있으나,이에 한정되지 않는다.예를들어, Mg（OH）2, MgC03,또는이들의조합일수있다.
[113] 상기 II원소함유화합물은 II의수산화물,산화물,질화물,탄산화물,또는
이들의조합을포함할수있으나,이에 한정되지 않는다.예를들어, 11（0¾2, 1102 ，또는이들의조합일수있다.
[114] 상기 M원소함유화합물은（¾, , Mg및끄를제외한원소주기율표제 3족
내지 제 12족원소로부터선택된 1종이상의원소의수산화물,산화물,질화물, 탄산화물,또는이들의조합을포함할수있으나,이에 한정되지 않는다.예를 들어, 0. ¾1（0¾2또는 0.9必10.05（0¾2일수있다.
[115] 상기 8원소함유화합물은 8의수산화물,산화물,질화물,탄산화물,
암모늄화물,또는이들의조합을포함할수있으나,이에 한정되지 않는다.예를 들어 ,어¾）28일수있다.
[116] 상기 열처리 단계는제 1열처리단계 및제 2열처리단계를포함할수있다. 상기 제 1열처리 단계및제 2열처리 단계는연속적으로수행되거나,제 1열처리 단계 이후에휴식기를가질수있다.또한,상기제 1열처리단계 및제 2열처리 단계는동일한챔버 내에서 이루어지거나,서로상이한챔버 내에서 이루어질수 있다.
[117] 상기제 1열처리단계에서의 열처리온도는상기제 2열처리단계에서의
열처리온도보다높을수있다.
[118] 상기제 1열처리단계는열처리온도 800°0내지 1200ᄋ（:에서수행될수있다. 상기 열처리온도는예를들어, 850 내지 1200ᄋ（:, 860°0내지 1200ᄋ（:, 870°0 내지 1200ᄋ（:, 880°0내지 1200ᄋ（:, 890°0내지 1200ᄋ（:,또는 900°0내지 1200ᄋ（：일수 있으나,이에 한정되지 않고,상기 범위내에 임의의두지점을선택하여구성된 범위를모두포함한다.
[119] 상기제 2열처리단계는열처리온도는 650°0내지 850 에서수행될수있다. 상기 열처리온도는 680°0내지 830ᄋ（:, 690°0내지 820ᄋ（:, 700°0내지 810ᄋ（:, 650°0 내지 800°（〕, 650°0내지 780°（〕, 650°0내지 760°（〕, 650°0내지 740°（〕, 650°0내지 720ᄋ（:,또는 680°0내지 720ᄋ（:일수있으나,이에 한정되지않고,상기범위내에 임의의두지점을선택하여구성된범위를모두포함한다.
[12이 일구현예에 따르면,상기제 1열처리단계에서의 열처리시간은상기제 2
열처리 단계에서의 열처리시간보다짧을수있다.
[121] 예를들어 ,상기 제 1열처리 단계에서 열처리시간은 3시간내지 시간, 4시간 내지 9시간,또는 5시간내지 8시간일수있으나,이에 한정되는것은아니며 , 상기 범위내에 임의의두지점을선택하여구성된범위를모두포함한다.
[122] 예를들어,상기 제 2열처리 단계에서 열처리시간은 15시간내지 25시간,
18시간내지 23시간일수있으나,이에 한정되는것은아니며 ,상기 범위내에 2020/175782 1»（：1^1{2019/018588
11
임의의두지점을선택하여구성된범위를모두포함한다.
[123] 상기제 1열처리단계는, 800°0내지 1200ᄋ (:의열처리온도에서 3내지 시간 열처리하는단계를포함할수있다.
[124] 상기제 2열처리단계는, 650°0내지 850ᄋ (:의열처리온도에서 15내지 23시간 열처리하는단계를포함할수있다.
[125] 상기제 1열처리단계는전구체화합물이층상구조의 -미함유리튬전이금속 산화물입자를형성함과동시에입자의성장을유발하여,단결정의형상을이룰 수있도록한다.상기제 1열처리단계에서는이차입자형상의 -미함유리튬 전이금속산화물입자내의각각의일차입자들이급격하게성장하여입자간 응력을견디지못함에따라일차입자들의내부가드러나면서서로융합되어, 이차전지용단결정양극활물질이형성되는것으로생각된다.상기제 2열처리 단계는제 1열처리단계에서보다낮은온도로열처리를장시간수행함으로써 , 제 1열처리단계에서생성된층상구조의결정도를높인다.제 1및제 2열처리 단계를통하여제 1영역을포함하는단일상,단결정,단일입자의고-니켈계 코발트-비함유 ((¾ -& 리튬전이금속산화물입자가얻어질수있다.
[126] 일구현예에따르면,상기양극활물질전구체를얻는단계에서,상기 (¾원소 함유화합물은유기용매중에포함될수있다.예를들어,상기유기용매는 휘발성용매일수있다.예를들어,상기유기용매는 80°0이하의온도에서 휘발성인용매 ,예를들어메탄올또는에탄올일수있다.
[127] 일구현예에따르면,상기소성하는단계는 500°0내지 900ᄋ (:의온도에서
수행될수있다.예를들어,상기소성하는단계는 600°0내지 900ᄋ (:의온도에서 수행될수있다.일구현예에따르면,상기소성하는단계는 1내지 6시간동안 수행될수있다.예를들어 ,상기소성하는단계는 2내지 4시간동안수행될수 있다.
[128] 일구현예에따르면,상기소성하는단계는 500°0내지 900ᄋ (:의온도에서 1 내지 6시간동안수행될수있다.상기소성온도및시간에서양극활물질 전구체를소성함으로써, (¾원자가농도구배를갖는농도구배영역을포함한 제 2영역이형성된양극활물질이얻어질수있다.
[129] 본발명의일구현예에따른양극활물질은, (¾ -비함유리튬전이금속산화물 입자를제조하는제 1단계;및 -비함유리튬전이금속산화물입자내부에 (¾ 농도구배를갖는농도구배영역을포함하는제 2영역을형성하는제 2단계로 요약된다.
[130] (¾ -비함유리튬전이금속산화물입자내부에 (¾농도구배영역을형성하는 것에의하여,단결정,단일입자내부에 (¾를포함하지않는제 1영역및 (¾ 농도구배를포함하는제 2영역을동시에포함할수있으며 ,이러한구조에 의하여고용량및장수명특성을가질수있다.
[131] 일구현예에따르면,상기제조방법에의해제조된리튬전이금속산화물은 단결정,단일입자이고,상기단결정은층상구조를가질수있다.또한,상기리튬 전이금속산화물의평균입경은 0.1/ffli내지 20/ffli일수있다.
[132] 또한,상기양극활물질의제조방법에의해제조된코발트-비함유리튬
전이금속산화물은 W, Mg및 Ti원소는구조내 M원소의자리에치환되고, S 원소가 0자리에치환되고, Na원소가 Li의자리에치환됨으로써 ,기존에 Ni2+의 산화를억제할뿐만아니라,기존에존재하는불안정한 Ni3+이온의 Ni2+ 이온으로의환원이유발되어구조적안정성및고밀도의리튬전이금속 산화물이얻어진다.또한,환원된 Ni2+이온과 Li+이온이이온반경이비슷하여 Li/Ni무질서화 (disordering)가촉진되어 , Li탈리시에빈격자를 Ni이온이 채움으로써결정의구조적안정성이도모된다.
[133] 그밖에양극활물질의구조및조성에관한내용은양극활물질에관한설명을 참고한다.
[134]
[135] 다른측면에따르면,전술한양극활물질을포함하는양극이제공된다.
[136] 또다른측면에따르면,상기양극;음극;및전해질;을포함하는리튬이차 전지가제공된다.
[137] 상기양극및이를포함하는리튬이차전지는다음과같은방법으로제조될수 있다.
[138] 먼저양극이준비된다.
[139] 예를들어,전술한양극활물질,도전재,바인더및용매가혼합된양극활물질 조성물이준비된다.상기양극활물질조성물이금속집전체위에직접코팅되어 양극판이제조된다.다르게는,상기양극활물질조성물이별도의지지체상에 캐스팅된다음,상기지지체로부터박리된필름이금속집전체상에
라미네이션되어양극판이제조될수있다.상기양극은상기에서열거한형태에 한정되는것은아니고상기형태이외의형태일수있다.
[140] 상기도전재로는천연흑연,인조흑연등의흑연;카본블랙;탄소나노튜브 등의도전성튜브;플루오로카본,산화아연,티탄산칼륨등의도전성위스커 ; 산화티탄등의도전성금속산화물;등이사용될수있으나,이들로한정되지 않으며,당해기술분야에서도전재로사용될수있는것이라면모두사용될수 있다.
[141] 상기바인더로는비닐리덴플루오라이드/핵사플루오로프로필렌코폴리머, 폴리비닐리덴플루오라이드 (PVDF),폴리아크릴로니트릴,
폴리메틸메타크릴레이트,폴리테트라플루오로에틸렌,그혼합물,금속염,또는 스티렌부타디엔고무계폴리머등이사용될수있으나,이들로한정되지않으며 당해기술분야에서바인더로사용될수있는것이라면모두사용될수있다.또 다른바인더의예로는,전술한폴리머의리튬염,나트륨염,칼슘염또는 Na염 등이사용될수있다.
[142] 상기용매로는 N-메틸피롤리돈,아세톤또는물등이사용될수있으나,이들로 한정되지않으며당해기술분야에서사용될수있는것이라면모두사용될수 2020/175782 1»（：1^1{2019/018588
13 있다.
[143] 상기 양극활물질,도전재,바인더 및용매의함량은리튬전지에서통상적으로 사용되는수준이다.리튬전지의용도및구성에 따라상기도전재,바인더 및 용매중하나이상이 생략될수있다.
[144] 다음으로음극이준비된다.
[145] 예를들어,음극활물질,도전재,바인더 및용매를혼합하여음극활물질
조성물이준비된다.상기음극활물질조성물이 3^내지 500^두께를갖는금속 집전체상에직접코팅 및건조되어음극판이 제조된다.다르게는,상기
음극활물질조성물이별도의지지체상에 캐스팅된다음,상기지지체로부터 박리된필름이금속집전체상에 라미네이션되어 음극판이제조될수있다.
[146] 상기음극집전체는,당해전지에 화학적 변화를유발하지 않으면서도전성을 가진것이라면특별히 제한되는것은아니며,예를들어,구리,니켈,구리의 표면에카본으로표면처리한것이사용될수있다.
[147] 상기음극활물질은당해기술분야에서 리튬전지의음극활물질로사용될수 있는것이라면모두가능하다.예를들어,리튬금속,리튬과합금가능한금속, 전이금속산화물,비전이금속산화물및탄소계재료로이루어진군에서선택된 하나이상을포함할수있다.
[148] 예를들어,상기 리튬과합금가능한금속은
Figure imgf000014_0001
06, 1¾, 31,예 ᅵ
합금（상기 는알칼리금속,알칼리토금속, 13족원소, 14족원소,전이금속, 희토류원소또는이들의조합원소이며, 는아님）, 811-¥합금（상기 는알칼리 금속,알칼리토금속, 13족원소, 14족원소,전이금속,희토류원소또는이들의
Figure imgf000014_0002
수있다.
[149] 예를들어,상기 전이금속산화물은리튬티탄산화물,바나듐산화물,리튬
바나듐산화물등일수있다.
[15이 예를들어,상기 비전이금속산화물은 ¾02, （¾（0＜＜2）등일수있다.
[151] 상기탄소계 재료로는결정질탄소,비정질탄소또는이들의혼합물일수있다. 상기 결정질탄소는무정형,판상,린편상여쇼句,구형또는섬유형의천연흑연 또는인조흑연과같은흑연일수있으며,상기 비정질탄소는소프트카본（80¾ 0^011：저온소성 탄소）또는하드카본（1 0때15011）,메조페이스피치（111680]31 86 ! 此）탄화물,소성된코크스등일수있다.
[152] 음극활물질조성물에서도전재,바인더 및용매는상기 양극활물질조성물의 경우와동일한것을사용할수있다.
[153] 상기음극활물질,도전재,바인더 및용매의 함량은리튬전지에서통상적으로 사용하는수준이다.리튬전지의용도및구성에 따라상기도전재,바인더 및 용매중하나이상이 생략될수있다. 2020/175782 1»（：1^1{2019/018588
14
[154] 다음으로,상기 양극과음극사이에삽입될세퍼레이터가준비된다.
[155] 상기세퍼레이터는리튬전지에서통상적으로사용되는것이라면모두사용 가능하다.전해질의 이온이동에 대하여 저저항이면서 전해액함습능력이 우수한것이사용될수있다.상기 세퍼레이터는단일막또는다층막일수 있으며,예를들어,유리섬유,폴리에스테르,테프론,폴리에틸렌,폴리프로필렌, 폴리비닐리덴플루오라이드,폴리테트라플루오로에틸렌（1 므¾또는이들의 조합물중에서선택된것으로서,부직포또는직포형태이어도무방하다.또한, 폴리에틸텐/폴리프로필렌 2층세퍼레이터 ,
폴리에틸텐/폴리프로필텐/폴리에틸렌 3층세퍼레이터 ,
폴리프로필텐/폴리에틸텐/폴리프로필렌 3층세퍼레이터등과같은혼합 다층막이사용될수있다.예를들어,리튬이온전지에는폴리에틸렌,
폴리프로필렌등과같은권취가능한세퍼레이터가사용되며 ,
리튬이온폴리머전지에는유기전해액함침 능력이우수한세퍼레이터가사용될 수있다.예를들어 ,상기 세퍼레이터는하기 방법에따라제조될수있다.
[156] 고분자수지 ,충진제 및용매를혼합하여세퍼레이터조성물이준비된다.상기 세퍼레이터조성물이 전극상부에직접코팅 및건조되어세퍼레이터가형성될 수있다.또는,상기세퍼레이터조성물이지지체상에 캐스팅 및건조된후,상기 지지체로부터 박리시킨세퍼레이터 필름이 전극상부에 라미네이션되어 세퍼레이터가형성될수있다.
[157] 상기세퍼레이터 제조에사용되는고분자수지는특별히 한정되지 않으며 , 전극판의 결합재에사용되는물질들이모두사용될수있다.예를들어, 비닐리덴플루오라이드/핵사플루오로프로필렌코폴리머 ,
폴리비닐리덴플루오라이드（1^0므）,폴리아크릴로니트릴,
폴리메틸메타크릴레이트또는이들의혼합물등이사용될수있다.
[158] 다음으로전해질이준비된다.
[159] 예를들어,상기 전해질은유기전해액일수있다.또한,상기 전해질은고체일 수있다.예를들어,보론산화물,리튬옥시나이트라이드등일수있으나이들로 한정되지 않으며 당해기술분야에서고체전해질로사용될수있은것이라면 모두사용가능하다.상기고체 전해질은스퍼터링등의방법으로상기음극상에 형성될수있다.
[160] 예를들어,유기전해액은유기용매에 리튬염이용해되어제조될수있다.
[161] 상기유기용매는당해기술분야에서유기용매로사용될수있는것이라면
모두사용될수있다.예를들어,프로필렌카보네이트,에틸렌카보네이트, 플루오로에틸렌카보네이트,부틸렌카보네이트,비닐렌카보네이트등의환상 카보네이트;디메틸카보네이트,디에틸카보네이트,메틸에틸카보네이트, 메틸프로필카보네이트,에틸프로필카보네이트,메틸이소프로필카보네이트, 디프로필카보네이트,디부틸카보네이트등의 쇄상카보네이트;아세트산메틸, 아세트산에틸,아세트산프로필,프로피온산메틸,프로피온산에틸, 1부티로락톤 등의에스테르류; 1,2 -디메톡시에탄, 1,2 -디에톡시에탄,테트라히드로푸란,
1,2 -디옥산, 2 -메틸테트라히드로푸란등의에테르류;아세토니트릴등의 니트릴류;디메틸포름아미드등의아미드류등이 있다.이들을단독또는복수개 조합하여사용할수있다.예를들어,환상카보네이트와쇄상카보네이트를 혼합한용매를사용할수있다.
[162] 또한,폴리에틸렌옥시드,폴리아크릴로니트릴등의중합체전해질에전해액을 함침한겔상중합체전해질이나, Lil, Li3N, LixGeyPzSa, LixGeyPzSaX6 (X=F, Cl, Br) 등의무기고체전해질을사용할수있다.
[163] 상기리튬염도당해기술분야에서리튬염으로사용될수있는것이라면
모두사용될수있다.예를들어, LiPF6, LiBF4, LiSbF6, LiAsF6, LiC104, LiCF3S03, Li(CF3S02)2N, LiC4F9S03, LiA102, L1AICI4, LiN(CxF2x+1S02)(CyF2y+1S02)(단 는 자연수), LiCl, Lil또는이들의혼합물등이다.
[164] 도 11에서보여지는바와같이상기리튬전지 (1)는양극 (3),음극 (2)및
세퍼레이터 (4)를포함한다.상술한양극 (3),음극 (2)및세퍼레이터 (4)가
와인딩되거나접혀서전지케이스 (5)에수용된다.이어서,상기전지케이스 (5)에 유기전해액이주입되고캡 (cap)어셈블리 (6)로밀봉되어리튬전지 (1)가
완성된다.상기전지케이스 (5)는원통형,각형,파우치형,코인형,또는박막형 등일수있다.예를들어,상기리튬전지 (1)는박막형전지일수있다.상기 리튬전지 (1)는리튬이온전지일수있다.
[165] 상기양극및음극사이에세퍼레이터가배치되어전지구조체가형성될수
있다.상기전지구조체가바이셀구조로적층된다음,유기전해액에함침되고, 얻어진결과물이파우치에수용되어밀봉되면리튬이온폴리머전지가완성된다.
[166] 또한,상기전지구조체는복수개적층되어전지팩을형성하고,이러한
전지팩이고용량및고출력이요구되는모든기기에사용될수있다.예를들어, 노트북,스마트폰,전기차량등에사용될수있다.
[167] 또한,상기리튬전지는수명특성및고율특성이우수하므로전기차량 (electric vehicle, EV)에사용될수있다.예를들어,플러그인하이브리드차량 (plug-in hybrid electric vehicle, PHEV)등의하이브리드차량에사용될수있다.또한,많은 양의전력저장이요구되는분야에사용될수있다.예를들어,전기자전거,전동 공구,전력저장용시스템등에사용될수있다.
[168]
[169] 이하의제조예,실시예및비교예를통하여본발명이더욱상세하게설명된다. 단,실시예는본발명을예시하기위한것으로서이들만으로본발명의범위가 한정되는것이아니다.
[17이
[171] (양극활물질의제조)
[172] 심시예 1
[173] 100g의 Ni0.8Mn0.2(OH)2와 4L8g의 Li2C03, 3.0g의 W03, 0.27g의 MgC03, 0.24g의 2020/175782 1»（：1^1{2019/018588
16
1102, 0.45은의 011및 0.75은의어¾）23를약 15분기계적으로혼합한다.혼합된 분말을 920°0 8시간및 700°0 20시간열처리하여（¾ -미함유리튬전이금속 산화물입자를얻었다.
[174] ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기
Figure imgf000017_0001
유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。（:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。（:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[175]
[176] 심시예 2
[177] 10 의 0.9必10.05（0¾2와 42.4§의 02003, 3. 의 03, 0.2걔의 MgC03, 0.24§의 1102, 0.45은의 011및 0.75은의어¾）23를약 15분기계적으로혼합한다.혼합된 분말을 880°0 4시간및 700°0 20시간열처리하여（¾ -미함유리튬전이금속 산화물입자를얻었다.
[178] ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기
Figure imgf000017_0002
유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。（:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。（:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[179]
[180] 비교예 1
[181] 10 의 08 102（0¾2와 41 의 02003, 3. 의 03, 0.2걔의 MgC03, 0.24¾의 1102, 0.45은의 011및 0.75은의어¾）23를약 15분기계적으로혼합한다.혼합된 분말을 920°0 8시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진 양극활물질의구체적인조성은표 1에서 확인할수있다.
[182]
[183] 비교예 2
[184] 10 의 0.8 10.2（0¾2와 41.8은의 02003, 0.45은의 011를약 15분기계적으로 혼합한다.혼합된분말을 920°0 8시간및 700°0 20시간열처리하여 양극활물질을 얻었다.얻어진양극활물질의구체적인조성은표 1에서확인할수있다.
[185]
[186] 비교예 3
[187] 10 의 Nio.8Mn0.2（OH）2와 41.8은의 1山（：03, 3. 의 03, 0.24은의 1102를약 15분 기계적으로혼합한다.혼합된분말을 920°0 8시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진양극활물질의구체적인조성은표 1에서 확인할 수있다.
[188]
[189] 비교예 4 2020/175782 1»（：1^1{2019/018588
17
[19이 10 의 Ni0.8Mn0.2(OH)2와 41 의 02003, 3. 의 03, 0.2걔의 MgC03, 0.2Ag$]
1102, 0.45은의 NaOH및 0.2은의 NH4F를약 15분기계적으로혼합한다.혼합된 분말을 920°0 8시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진 양극활물질의구체적인조성은표 1에서 확인할수있다.
[191]
[192] 비교예 5
[193] 10 의 Ni0.8Mn0.2(OH)2와 41.8은의 02003, 0.45은의 NaOH를약 15분기계적으로 혼합한다.혼합된분말을 920°0 8시간및 700°0 20시간열처리하여 (¾ -미함유 리튬전이금속산화물입자를얻었다.
[194] 이어서 ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기 함유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。 (:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。(:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[195]
[196] 비교예 6
[197] 10 의 Ni0.8Mn0.2(OH)2와 41.8은의 1山(：03, 3. 의 03, 0.24은의 1102를약 15분 기계적으로혼합한다.혼합된분말을 920°0 8시간및 700°0 20시간열처리하여 함유리튬전이금속산화물입자를얻었다.
[198] 이어서 ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기 함유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。 (:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。(:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[199]
[200] 비교예 7
[201] 10 의 Ni0.8Mn0.2(OH)2와 41 의 02003, 3. 의 03, 0.2걔의 MgC03, 0.24¾의 1102, 0.45은의 NaOH및 0.2은의 NH4F를약 15분기계적으로혼합한다.혼합된 분말을 920°0 8시간및 700°0 20시간열처리하여 (¾ -미함유리튬전이금속 산화물입자를얻었다.
[202] ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기
Figure imgf000018_0001
유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。 (:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。(:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[203]
[204] 비교예 8
[205] 10 의 0.9必1_(0¾2와 42.4§의 02003, 3. 의 \¥03, 0.2걔의 MgC03, 0.24§의 2020/175782 1»（：1^1{2019/018588
18
1102, 0.45은의 011및 0.75은의어¾)23를약 15분기계적으로혼합한다.혼합된 분말을 880°0 4시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진 양극활물질의구체적인조성은표 1에서 확인할수있다.
[206]
[207] 비교예 9
[208] 10 의 0.9必1_(0¾2와 41.8은의 !山(：03, 0.45은의 NaOH를약 15분기계적으로 혼합한다.혼합된분말을 880°0 8시간및 700°0 20시간열처리하여 양극활물질을 얻었다.얻어진양극활물질의구체적인조성은표 1에서확인할수있다.
[209]
[210] 비교예 10
[211] 10 의 0.9必10.05(0¾2와사抑의 02003, 3. 의 03, 0.2起의끄02를약 15분 기계적으로혼합한다.혼합된분말을 880°0 8시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진양극활물질의구체적인조성은표 1에서 확인할 수있다.
[212]
[213] 비교예 11
[214] 10 의 0.9必1_(0¾2와 41抑의 02003, 3. 의 \¥03, 0.2걔의 MgC03, 0.24§의 1102, 0.45은의 NaOH및 0.2은의 NH4F를약 15분기계적으로혼합한다.혼합된 분말을 880°0 8시간및 700°0 20시간열처리하여 양극활물질을얻었다.얻어진 양극활물질의구체적인조성은표 1에서 확인할수있다.
[215]
[216] 己예 12
[217] 10 의 0.9必1_(0¾2와 41.8은의 !山(：03, 0.45은의 NaOH를약 15분기계적으로 혼합한다.혼합된분말을 880°0 8시간및 700°0 20시간열처리하여 (¾ -미함유 리튬전이금속산화물입자를얻었다.
[218] 이어서 ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기 함유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。 (:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。(:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[219]
Figure imgf000019_0001
기계적으로혼합한다.혼합된분말을 880°0 8시간및 700°0 20시간열처리하여 함유리튬전이금속산화물입자를얻었다.
[222] 이어서 ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기 함유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。 (:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。(:에서 2020/175782 1»（：1^1{2019/018588
19
3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
Figure imgf000020_0001
02003, 3. 의 03, 0.2걔의 MgC03, 0.24§£] 1102, 0.45은의 NaOH및 0.2은의 NH4F를약 15분기계적으로혼합한다.혼합된 분말을 880°0 8시간및 700°0 20시간열처리하여（¾ -미함유리튬전이금속 산화물입자를얻었다.
[226] 이어서 ,에탄올중에 4은의코발트아세테이트가용해된용액에 의상기
-미함유리튬전이금속산화물입자를첨가하고 30분간교반하고,혼합 용액을 80。（:에서방치하여 에탄올을증발시킨후,얻어진분말을 800。（:에서 3시간소성하여,양극활물질을얻었다.얻어진양극활물질의구체적인조성은 표 1에서확인할수있다.
[227]
[228]
[229] （하프셀의 제조）
[23이 심시예 3
[231] 실시예 1에서 얻은양극활물질:도전재:바인더를 94:3:3의중량비율로
혼합하여슬러리를제조하였다.여기서,상기도전재로는카본블랙을 사용하였고,상기 바인더로는폴리비닐리덴플루오라이드（1^（正）를
메틸- 2 -피롤리돈용매에용해시켜서사용하였다.
[232] 상기슬러리를신집전체에균일하게도포하고, 1 ᄋ（：에서 2시간건조하여 양극전극을제조하였다.극판의로딩 레벨은 11.0
Figure imgf000020_0002
이고,전극밀도는 3.6 은/<:<:이었다.
[233] 상기제조된양극을작업전극으로사용하고,리튬호일을상대전극으로
사용하고, EC/EMC/DEC를 3/4/3의부피비로혼합한혼합용매에 리튬염으로 1^ ¾를 1.3M의농도가되도록첨가한액체 전해액을사용하여통상적으로 알려져 있는공정에 따라 12032하프셀을제작하였다.
[234]
[235] 심시예 4
[236] 실시예 1에서 얻은양극활물질대신에 ,실시예 2에서 얻은양극활물질을각각 사용한점을제외하고는,실시예 3와동일한방법으로하프셀을제작하였다.
[237]
[238] 비교예 15내지 28
[239] 실시예 1에서 얻은양극활물질대신에,비교예 1내지 14에서 얻은
양극활물질을각각사용한점을제외하고는,실시예 3와동일한방법으로 하프셀을제작하였다. 2020/175782 1»(：1/10公019/018588
20
[24이 [표 1]
Figure imgf000021_0001
Figure imgf000022_0004
[241]
[242] 평가예 1:양극활물짐의조성평가
[243] 실시예 1과비교예 1,및실시예 2와비교예 8에서합성한양극활물질에대하여 700-ES（Varian）장비를이용하여 inductively coupled plasma（ICP）분석을 진행하였고,그결과는하기표 2및 3에각각기재하였다.
[244] 표 2및 3을참고하면,비교예 1와실시예 1,및비교예 8와실시예 2의 ICP분석 결과,실시예 1및실시에 2의양극활물질의경우 Na이 Li자리에 0.（）1몰 치환됨을알수있으며, 0.01몰의 W, 0.003몰의 Mg, 0.003몰의 Ti가전이금속 자리에치환됨을알수있다.또한, Co농도구배영역의도입에따라전체조성중 Co의농도가약 3몰%증가하였음을확인하였다. S는전이금속또는 Li의몰수에 영향을주지않는것으로보아, 0의일부를치환하는것으로생각된다. ICP분석 시,진공에서분석을하더라도미량의대기중의산소및이산화탄소의 유입으로인해물질에포함된산소의화학량론적값은분석하기힘들다.
[245] [표 2]
Figure imgf000022_0002
[246] [표 3]
Figure imgf000022_0003
[247] 평가예 2:양극활물짐의 입도평가
[248] 실시예 1과비교예 1,및실시예 2와비교예 8에서합성한양극활물질의외관을
460 만사）장비를이용하여
Figure imgf000022_0001
2知）에서보여주었다.또한,（그 1090（8011100사）장비를이용하여입도분포를 각각측정하여하기표 4와도 1（비및표 5와도 2（비에서나타내었다.
[249] 표 4,및도 1知）및도 1（비를참고하면,실시예 1의단입자형양극활물질은
비교예 1의단입자형양극활물질과입경의큰차이가관찰되지않았으며, 농도구배영역이별도의두께를갖는층으로존재하지않는것을시사하는 것이다.
[25이 또한,표 5및도 2（幻및도 2（비를참고하면,앞선실시예 1에서말한바와같이, 실시예 2의경우도입경의차이가크지않은것으로볼때,농도구배영역이 별도의두께를갖는층으로존재하지않는것을시사하는것이다. [251] [표 4]
Figure imgf000023_0001
[252] [표 5]
Figure imgf000023_0002
[253] 평가예 3:양극활물짐의농도구배영역평가
[254] 실시예 1및비교예 1에서얻은양극활물질,및실시예 2및비교예 8에서얻은 양극활물질에대하여 ,고해상도투과전자현미경 (high resolution transmission electron microscopy (HR-TEM))을이용하여사진을찍었고,에너지분산형 x-레이 분광학 (energy dispersive X-ray spectroscopy (EDX))분석을진행하였다.그결과는 하기표 6내지 9,및도 3내지 6에서보여진다.
[255] [표 6]
Figure imgf000023_0003
[256] [표 7]
Figure imgf000023_0004
2020/175782 1»(：1^1{2019/018588
23
[257] [표 8]
Figure imgf000024_0003
[258] [표 9]
Figure imgf000024_0004
[259] 표 6및도 3을참고하면,양극활물질내전이금속,예를들어 및 Mn의
농도가양극활물질의표면및중심방향으로실질적으로일정하게유지되고 있음을알수있다.
[26이 표 7및도 4를참고하면,양극활물질내전이금속중, (¾의농도는
양극활물질의표면으로부터중심방향으로감소하여 5번위치에서는 가 존재하지않음을알수있고, 의농도는반대로증가하는경향성을
확인하였다.또한,
Figure imgf000024_0001
농도구배층은약 500 11111인것을알수있었다.특정이론에 구속됨없이,전이금속중코발트이온은니켈이온대비층상구조를지니는 양극활물질의구조적안정성에기여를하므로,양극활물질의표면에
상대적으로안정한코발트가과량포함됨으로써충방전시양극활물질의구조적 안정성을향상시켜서장수명특성을향상시킬것으로생각된다.
[261] 표 8및도 5을참고하면,양극활물질내전이금속,예를들어 및신의농도가 양극활물질의표면및중심방향으로실질적으로일정하게유지되고있음을알 수있다.
[262] 표 9및도 6을참고하면,양극활물질내전이금속중, (¾의농도는
양극활물질의표면으로부터중심방향으로감소하여 5번위치에서는 가 존재하지않음을알수있고, 의농도는반대로증가하는경향성을
확인하였다.또한,
Figure imgf000024_0002
농도구배층은약 500 11111인것을알수있었다.특정이론에 구속됨없이,전이금속중코발트이온은니켈이온대비층상구조를지니는 양극활물질의구조적안정성에기여를하므로,양극활물질의표면에 2020/175782 1»（：1^1{2019/018588
24 상대적으로안정한코발트가과량포함됨으로써충방전시양극활물질의구조적 안정성을향상시켜서장수명특성을향상시킬것으로생각된다.
[263] 평가예 4:상온수명평가
[264] 실시예 3내지 4및비교예 15내지 28에서제작한하프셀을 시간휴지시킨 후, 0.1（：로 4. 까지（X 1110（^로충전한뒤, 0.05（：에해당하는전류까지어 1110（^로충전을진행하였다.다음, 0.1（：로 3.0¥까지（X 1110（^로방전하여화성 공정을완료하였다.
[265] 이어서 ,상온（25ᄋ 0에서 0.5（：로 4. 까지（X—（노로충전한뒤 , 0.05（：에
해당하는전류까지（：\ 110（노로충전을진행하였다.다음, 1（：로 3.0¥까지 00 1110（노로방전을진행하였으며,이과정을총 100회반복하였다.
[266] 초기용량에대하여 100회충전및방전후의용량유지율을계산하였고,그 결과는하기표 에서보여진다.또한,사이클에따른용량유지율을나타낸 그래프는도 7내지 에서보여진다.
2020/175782 1»（：1/10公019/018588
25
［267］ ［표 1이
Figure imgf000026_0001
2020/175782 1»（：1^1{2019/018588
26
Figure imgf000027_0005
[268] 표 및도 7및 8을참고하면,실시예 3및비교예 15의상온수명결과에
따르면,농도구배영역을포함하는제 2영역을포함하는양극활물질을적용한 실시예 3이 100사이클에서약 7%높은수명유지율을나타냈다.이는실시예 3에서사용한양극활물질이 (¾를포함하지않음에도불구하고,구조내 리튬자리에 Na원소가도입되어니켈이온의자발적환원이억제되고
전기화학적으로비활성적인상생성이억제된다.더욱이
Figure imgf000027_0001
원소의도입은구조내 이온의 0 를증가시켜구조적안정성을 향상시키며,전이금속과산소간의결합세기를증가시켜전기화학평가시 ,구조 내산소방출을억제시켜전해액과의부반응을억제할수있다.더욱이, 산소자리에치환되는 3원소는산소대비전기음성도가높아전이금속-산소간의 결합력을증가시킴과동시에활물질의전도도를향상시킬수있다.또한,
-비함유리튬전이금속산화물을포함하는제 1영역을감싸는 (¾
농도구배영역을포함하는제 2영역의도입에따라전기화학반응에서구조적 안정성의향상에의하여수명특성이향상된것으로생각된다.따라서, 5종의 추가원소도입및 농도구배영역의도입은양극활물질의구조적안정성을 제공해줄뿐만아니라활물질의전도도를향상시킴으로써전기화학적수명 안정성을향상시킬수있다.또한,실시예 3은 원소가도입된비교예 16,
Figure imgf000027_0002
II가도입된비교예 17,및 Na, W, Mg, Ti, F원소가도입된비교예 18에비하여 100사이클에서최대약 18%향상된수명특성을보였으며, Na원소가도입되고 제 2영역을포함하는비교예 19, , II가도입되고제 2영역을포함하는비교예 20,및 Na, W, Mg, Ti, F원소가도입되고제 2영역을포함하는비교예 21에비하여 100사이클에서최대약 10%향상된수명특성을보였다.이는 Na및 3가 도입되고, , Mg, II중적어도 1종의원소가도입되고,제 2영역을동시에 포함하는경우에시너지효과가발생됨을시사하는것이다.
[269] 표 과도 9및 을참고하면,니캘-알루미늄계양극활물질을사용하는
실시예 4의경우도농도구배영역을포함하는제 2영역을도입함에따라,이러한 농도구배영역을포함하지않는비교예 22에비해 0사이클에서약 9%향상된 수명특성을보였다.또한,실시예 4는 원소가도입된비교예 23, \¥, 11가 도입된비교예 24,
Figure imgf000027_0003
원소가도입된비교예 25에비하여
100사이클에서최대약 27%향상된수명특성을보였으며, Na원소가도입되고 제 2영역을포함하는비교예 26, , II가도입되고제 2영역을포함하는비교예 27,
Figure imgf000027_0004
원소가도입되고제 2영역을포함하는비교예 28에비하여 100사이클에서최대약 21%향상된수명특성을보였다.이는 Na및 3가 2020/175782 1»（：1^1{2019/018588
27 도입되고, , Mg, II중적어도 1종의원소가도입되고,제 2영역을동시에 포함하는경우에시너지효과가발생됨을시사하는것이다.
[27이 이상에서는도면및실시예를참조하여본발명에따른바람직한구현예가 설명되었으나,이는예시적인것에불과하며,당해기술분야에서통상의지식을 가진자라면이로부터다양한변형및균등한타구현예가가능하다는점을 이해할수있을것이다.따라서,본발명의보호범위는첨부된특허청구범위에 의해서정해져야할것이다.

Claims

2020/175782 1»（：1/10公019/018588 28 청구범위
[청구항 1] 니의일부가 으로치환되고,제 1영역및제 2영역을포함하고,
상기제 1영역은 (¾원소이외의원소를포함하고,상기제 2영역은 (¾ 원소를포함하고,
상기제 2영역은 (¾원자의농도가변화하는농도구배영역을포함하는 리튬전이금속산화물입자를포함한,양극활물질.
[청구항 2] 제 1항에 있어서,
상기제 1영역은상기리튬전이금속산화물입자의내부를형성하고, 상기제 2영역은상기리튬전이금속산화물입자의외곽부를형성하는, 양극활물질.
[청구항 3] 제 1항에 있어서,
상기농도구배영역에서상기 (¾원자의농도는외부측을향해증가하는 농도구배를갖는,양극활물질.
[청구항 4] 제 1항에 있어서,
상기농도구배영역은 원자를더포함하고,
상기 원자의농도는외부측을향해감소하는농도구배를갖는, 양극활물질.
[청구항 5] 제 1항에 있어서,
상기농도구배영역은 500 ! 1이하의두께를갖는,양극활물질.
[청구항 6] 제 1항에 있어서,
상기제 1영역은하기화학식 1로표시되는,양극활물질:
[화학식 1]
나 ’ -爲
상기화학식 1중,
M은 00, Mg및끄를제외한원소주기율표제 3족내지제 12족 원소로부터선택된 1종이상의원소를포함하고;
중에서선택된 1종이상의원소를포함하고,
Figure imgf000029_0001
0＜2：＜1, 0＜1;＜0.01이다.
[청구항 7] 제 6항에 있어서,
상기 및 는 0¾分+幻£0.02를만족하는,양극활물질.
[청구항 8] 제 1항에 있어서,
상기제 1영역은하기화학식 2로표시되는양극활물질:
[화학식 2]
LixNa1-xM1-(a+p+Y)WaMgpTig02 - ^
상기화학식 2중,
Figure imgf000029_0002
2020/175782 1»（：1^1{2019/018588
29
0< <0.01, 0<(¾<0.01, 0<(3<0.005, 0<7<0.005, 0<1<0.01, 0<。1+(3+7<0.02이다. ［청구항 9］ 제 8항에 있어서,
상기화학식 2중, (3및 7는각각 0<(3<0.003, 0< <0.003인,양극활물질.
［청구항 10］ 제 8항에 있어서,
상기 M은 , 신, V, ¾：8및 I5중에서선택된 1종이상의원소를 포함하는,양극활물질.
［청구항 11］ 제 1항에 있어서,
상기리튬전이금속산화물은단일입자인,양극활물질.
［청구항 12］ 제 1항에 있어서,
상기리튬전이금속산화물은단결정인,양극활물질.
［청구항 13］ 제 1항에 있어서,
상기제 1영역은하기화학식 3또는 4로표시되는,양극활물질:
［화학식 3］
Figure imgf000030_0001
상기화학식 4에서,
Figure imgf000030_0002
［청구항 14］ 제 1항에 있어서,
상기제 2영역은하기화학식 5로표시되는,양극활물질:
［화학식 5］
니 &1 1(:0)，1］ᆻ［1)，2］ᆻ［ 102나1¾
상기화학식 5중,
Figure imgf000030_0003
주기율표제 3족내지제 12족 원소로부터선택된 1종이상의원소를포함하고;
중에서선택된 1종이상의원소를포함하고,
Figure imgf000030_0004
1, 0 2<1, 0< <1, 0산1<0.()1이다.
［청구항 15］ 제 I4항에 있어서,
상기화학식 5는 0 < /( + 2+21)<0.2인,양극활물질.
［청구항 16］ 니의일부가 으로치환되고, (¾원소이외의원소를포함하는전구체 화합물을준비하는단계 ;
상기전구체화합물을열처리하여 (：0 -미함유 (
Figure imgf000030_0005
산화물입자를얻는단계 ;
Figure imgf000030_0006
산화물입자, (¾원소함유화합물을 2020/175782 1»（：1^1{2019/018588
30 혼합하여양극활물질전구체를얻는단계;및
상기양극활물질전구체를소성하여양극활물질을얻는단계;
를포함하는양극활물질의제조방법 .
［청구항 17］ 제 16항에 있어서,
상기전구체화합물을준비하는단계는:
니원소함유화합물, Na원소함유화합물, 원소함유화합물,
Figure imgf000031_0001
원소 함유화합물, II원소함유화합물, M원소함유화합물및 8원소함유 화합물을혼합하는단계를포함하고,상기
Figure imgf000031_0002
원소는전이금속을 포함하는,양극활물질의제조방법.
［청구항 18］ 제 I7항에 있어서,
상기혼합단계는기계적혼합하는단계를포함하는,양극활물질의 제조방법.
［청구항 19］ 제 16항에 있어서,
상기열처리단계는제 1열처리단계및제 2열처리단계를포함하고, 상기제 1열처리단계의열처리온도는제 2열처리단계의열처리 온도보다높은,양극활물질의제조방법 .
［청구항 2이 제 1항내지제 15항중어느한항에따른양극활물질을포함하는양극;
음극;및
전해질;
을포함하는리튬이차전지.
PCT/KR2019/018588 2019-02-28 2019-12-27 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지 WO2020175782A1 (ko)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2021548277A JP7258373B6 (ja) 2019-02-28 2019-12-27 正極活物質、その製造方法、及びそれを含む正極を含むリチウム二次電池
CN201980091469.1A CN113412548A (zh) 2019-02-28 2019-12-27 阳极活性物质、其制备方法以及包括该阳极活性物质的阳极的锂二次电池
US17/425,531 US20220190316A1 (en) 2019-02-28 2019-12-27 Positive active material, method for manufacturing same and lithium secondary battery comprising positive electrode comprising positive active material
EP19916791.7A EP3933983A4 (en) 2019-02-28 2019-12-27 POSITIVE ACTIVE MATERIAL, PROCESS FOR ITS MANUFACTURE AND LITHIUM SECONDARY BATTERY WITH POSITIVE ELECTRODE CONTAINING POSITIVE ACTIVE MATERIAL

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR10-2019-0024389 2019-02-28
KR20190024389 2019-02-28
KR1020190176119A KR102159701B1 (ko) 2019-02-28 2019-12-27 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
KR10-2019-0176119 2019-12-27

Publications (1)

Publication Number Publication Date
WO2020175782A1 true WO2020175782A1 (ko) 2020-09-03

Family

ID=72240072

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2019/018588 WO2020175782A1 (ko) 2019-02-28 2019-12-27 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지

Country Status (3)

Country Link
US (1) US20220190316A1 (ko)
JP (1) JP7258373B6 (ko)
WO (1) WO2020175782A1 (ko)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102144056B1 (ko) * 2019-12-24 2020-08-12 주식회사 에스엠랩 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
US11764355B2 (en) * 2020-01-22 2023-09-19 Uchicago Argonne, Llc Cathode active materials for secondary batteries

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006054159A (ja) * 2004-07-15 2006-02-23 Sumitomo Metal Mining Co Ltd 非水系二次電池用正極活物質およびその製造方法
KR20100060362A (ko) * 2008-11-27 2010-06-07 주식회사 에너세라믹 리튬 이차 전지용 양극 활물질, 이의 제조방법 및 이를 포함하는 리튬 이차 전지
KR20120079802A (ko) * 2011-01-05 2012-07-13 한양대학교 산학협력단 입자 전체 농도 구배 리튬이차전지 양극활물질, 이의 제조 방법, 및 이를 포함하는 리튬 이차 전지
CN103928675A (zh) * 2014-04-18 2014-07-16 东莞市迈科科技有限公司 一种镍锰酸锂正极材料及其制备方法
KR20160098315A (ko) * 2013-12-13 2016-08-18 가부시키가이샤 산도쿠 정극 활물질 분말, 이 분말을 갖는 정극 및 이차전지

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5259078B2 (ja) 2006-11-22 2013-08-07 パナソニック株式会社 非水電解質二次電池用正極活物質及びその製造方法、ならびに、該正極活物質を用いた非水電解質二次電池
JP2018014208A (ja) 2016-07-20 2018-01-25 住友金属鉱山株式会社 非水系電解質二次電池用正極活物質とその製造方法
EP3279977B1 (en) 2016-08-02 2020-03-11 Ecopro Bm Co., Ltd. Lithium complex oxide for lithium secondary battery positive active material and a method of preparing the same
CN113711391A (zh) 2019-01-07 2021-11-26 株式会社Lg新能源 正极活性材料、该正极活性材料的制备方法及包含该正极活性材料的正极和锂二次电池

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006054159A (ja) * 2004-07-15 2006-02-23 Sumitomo Metal Mining Co Ltd 非水系二次電池用正極活物質およびその製造方法
KR20100060362A (ko) * 2008-11-27 2010-06-07 주식회사 에너세라믹 리튬 이차 전지용 양극 활물질, 이의 제조방법 및 이를 포함하는 리튬 이차 전지
KR20120079802A (ko) * 2011-01-05 2012-07-13 한양대학교 산학협력단 입자 전체 농도 구배 리튬이차전지 양극활물질, 이의 제조 방법, 및 이를 포함하는 리튬 이차 전지
KR20160098315A (ko) * 2013-12-13 2016-08-18 가부시키가이샤 산도쿠 정극 활물질 분말, 이 분말을 갖는 정극 및 이차전지
CN103928675A (zh) * 2014-04-18 2014-07-16 东莞市迈科科技有限公司 一种镍锰酸锂正极材料及其制备方法

Also Published As

Publication number Publication date
JP7258373B6 (ja) 2024-02-13
US20220190316A1 (en) 2022-06-16
JP2022521211A (ja) 2022-04-06
JP7258373B2 (ja) 2023-04-17

Similar Documents

Publication Publication Date Title
KR102144056B1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
KR102005513B1 (ko) 리튬 이차전지용 양극 활물질, 이의 제조 방법, 이를 포함하는 전극, 및 상기 전극을 포함하는 리튬 이차 전지
KR102175126B1 (ko) 양극활물질, 이의 제조방법 및 상기 양극활물질을 포함하는 양극을 포함한 리튬이차전지
KR102159701B1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
KR102144057B1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
KR102178781B1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
JP2023524021A (ja) リチウム二次電池用正極活物質、その製造方法及びそれを含むリチウム二次電池
WO2020175782A1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
JP7258372B2 (ja) 正極活物質、その製造方法、及びそれを含む正極を含むリチウム二次電池
JP7262851B2 (ja) 正極活物質、その製造方法、及びそれを含む正極を含むリチウム二次電池
JP7230227B2 (ja) 正極活物質、その製造方法、及びそれを含む正極を含むリチウム二次電池
KR102214463B1 (ko) 양극활물질, 이의 제조방법 및 상기 양극활물질을 포함하는 양극을 포함한 리튬이차전지
KR20210020687A (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지
CN114762149B (zh) 正极活性材料、所述正极活性材料的制备方法以及具有包括所述正极活性材料的正极的锂二次电池
KR102172381B1 (ko) 양극활물질, 이의 제조방법 및 이를 포함하는 양극을 포함한 리튬이차전지

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: 19916791

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2021548277

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2019916791

Country of ref document: EP

Effective date: 20210928