High-level nickel compound and production method thereof

Abstract

To provide: a high-level nickel compound having a low cobalt content, enabling cost reduction; and a production method thereof.SOLUTION: A general chemical formula of a high-level nickel compound is LiaNixCoyMnzMbO2 cα dβ where 1≤a≤1.2, 0<b≤0.01, 0<c≤0.01, 0<d≤0.02, 0.8≤x≤1, 0≤y<0.12, 0≤z≤0.2, and x+y+z=1 are satisfied, M is a doping element, α is a first coating, and β is a second coating. A production method of the high-level nickel compound can employ a plurality of coating processes to suitably reduce residual alkali, enabling solvent washing and a recovery process to be reduced or avoided.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the field of lithium ion batteries, and more particularly to high nickel compounds and methods for their manufacture. [Background technology]

[0002] With the rapid development of the new energy market, high-nickel lithium batteries (Ni mole fraction ≥ 0.6) are attracting increasing attention as an environmentally friendly energy storage material. As one of the most important components of lithium batteries, the cathode material directly affects battery performance. The structural characteristics and manufacturing process of the high-nickel compounds used in the cathode material play a crucial role in the performance and application of lithium batteries. For example, a high cobalt content in the raw materials used to manufacture high-nickel compounds increases raw material costs, and the manufacturing process also has a certain impact on the crystal structure and performance (e.g., electrochemical properties) of the high-nickel compounds, thereby affecting aspects such as the structural stability, rate capability, storage capacity, and cycling performance of the cathode material.

[0003] Therefore, there is a need to further improve existing high-nickel compounds and their manufacturing methods. Summary of the Invention [Problem to be solved by the invention]

[0004] One of the objects of the present application is to provide a high nickel compound for forming a positive electrode material for lithium batteries and a method for making the same. [Means for solving the problem]

[0005] One embodiment of the present application provides a high nickel compound having the general chemical formula Li a Ni x Co y Mn z M bIt is O2·cα·dβ, where 1≦a≦1.2, 0<b≦0.01, 0<c≦0.01, 0<d≦0.02, 0.8≦x≦1, 0≦y<0.12, 0≦z≦0.2, x + y + z = 1, M is a doping element, α is the first coating, and β is the second coating.

[0006] Another embodiment of the present application also provides a positive electrode plate including a positive electrode current collector and a positive electrode active material containing the high-nickel compound.

[0007] Yet another embodiment of the present application provides an electrode assembly including a negative electrode plate containing a negative electrode current collector and a negative electrode active material disposed on the negative electrode current collector, and the positive electrode plate.

[0008] The fourth embodiment of the present application further provides a battery including the electrode assembly.

[0009] The fifth embodiment of the present application further provides an electrical device including the battery, and the battery is used to supply electrical energy.

[0010] The sixth embodiment of the present application is as follows: (1) Mix a lithium source, a nickel-cobalt-manganese precursor, and an M source, and perform a first firing treatment to produce a first main material. Here, the M source is a compound containing element M, and the general formula of the first main material is Li a Ni x Co y Mn z M b O2, where 1≦a≦1.2, 0<b≦0.01, 0.8≦x≦1, 0≦y<0.12, 0≦z≦0.2, and x + y + z = 1; (2) Mix the first main material with an A source and perform a second firing treatment to produce a second main material. Here, the A source is a compound containing element A; and (3) Mix the second main material with a B source and perform a third firing treatment. Here, the B source is a compound containing element boron. The present application further provides a method for manufacturing a high-nickel compound.

Advantages of the Invention

[0011] Compared with the prior art, the high nickel compound and its manufacturing method provided in the examples of the present application have a low cobalt content, which can reduce costs. [Brief explanation of the drawings]

[0012] The following briefly describes the drawings necessary for explaining the embodiments of the present application or the prior art, to facilitate the description of the embodiments of the present application. It is clear that the drawings described below are only some of the embodiments of the present application. Those skilled in the art can obtain drawings of other embodiments based on the structures shown in these drawings without any innovative ingenuity. [Figure 1] FIG. 1 is a schematic diagram according to the method for producing high nickel compounds according to some embodiments of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0013] In order to better understand the spirit of the embodiments of the present application, some preferred embodiments of the present application are given below for further explanation.

[0014] Examples of the present application are specifically described in the specification below. Throughout this specification, the term "about" is used to describe and account for small variations. When used in conjunction with an event or circumstance, the term can refer to an instance where the event or circumstance occurred exactly, as well as an instance where the event or circumstance occurred very similarly. For example, when used in conjunction with a numerical value, the term can refer to a variation range of ±10% or less of the numerical value, such as ±5% or less, ±4% or less, ±3% or less, ±2% or less, ±1% or less, ±0.5% or less, ±0.1% or less, or ±0.05% or less. For example, two numerical values ​​can be considered "about" the same if the difference between them is ±10% or less of the mean value of the numerical values ​​(e.g., ±5% or less, ±4% or less, ±3% or less, ±2% or less, ±1% or less, ±0.5% or less, ±0.1% or less, or ±0.05% or less).

[0015] In this specification, amounts, ratios, and other numerical values may be presented in a range format. Such a range format is for convenience and brevity and should be interpreted flexibly so as to include not only the explicitly specified numerical values as limitations of the range but also all individual numerical values or sub-ranges included within the range as if each numerical value and sub-range were explicitly specified.

[0016] Also, for ease of explanation, in this specification, words such as "first", "second", etc. may be used to distinguish one substance or a series of substances, and these words can be interpreted as names.

[0017] The general chemical formula of the high-nickel compound proposed in this application is Li a Ni x Co y Mn z M b O2·cα·dβ, where 1.00≦a≦1.20, 0.00 < b≦0.01, 0.00 < c≦0.01, 0.00 < d≦0.02, 0.80≦x<1.00, 0.00≦y<0.12, 0.00≦z<0.2, and x + y + z = 1, M is a doping element, α is the first coating, and β is the second coating.

[0018] Since the cobalt content of the raw materials used in the high-nickel compound proposed in this application is relatively low, the raw material cost is significantly reduced.

[0019] In the case of a high-nickel cathode material with a nickel molar fraction exceeding about 0.6, for example, a high-nickel cathode material with a nickel molar fraction exceeding about 0.8, appropriate reduction of residual alkali can be achieved by adopting a plurality of coating processes, and the solvent washing and recovery processes can be reduced or avoided.

[0020] The doping element M is used to partially substitute the nickel-cobalt-manganese spatial sites, which stabilizes the framework structure, inhibits structural collapse, and stabilizes the spatial structure during charge and discharge. At the same time, its relatively large ionic radius can provide larger lithium ion channels and improve the material capacity. For example, M can be selected from one or more elements of Group VB and Group VIB.

[0021] The first coating α is used as a surface coating and is concentrated on the surface of the primary particles. It can effectively relieve stress caused by volume changes in the primary particles during charge and discharge, and improve the stability of the primary particles. For example, α is selected from compounds containing one or more elements from Group VB and Group VIB, such as WO3, MoO3, or Nb2O5.

[0022] The second coating β is used as a surface coating to prevent direct contact between the positive electrode material and the electrolyte and to suppress side reactions between the positive electrode material and the electrolyte, thereby improving safety performance. For example, β may be selected from one or more of boric acid, lithium borate, lithium metaborate, lithium tetraborate, and other boron-containing compounds, or may be selected from compounds formed from one or more of boric acid, lithium borate, lithium metaborate, lithium tetraborate, and other boron-containing compounds. Exemplarily, β may be Li3BO3, LiBO2, or Li2B4O7.

[0023] According to some embodiments of the present application, the specific surface area of ​​the high nickel compound is about 0.1 to 1.5 m 2 / g and the average particle size may be about 2 to 15 μm. For example, the average particle size of the high-nickel compound may be about 5 to 15 μm and may be a single crystal or polycrystalline compound. The total free lithium contained in the high-nickel compound is less than about 1500 ppm by mass.

[0024] According to some embodiments of the present application, in the X-ray diffraction spectrum of the high nickel compound, the ratio FWHM(006) / FWHM(102) of the full width at half maximum (FWHM(006)) of the (006) diffraction peak at about 37.9° to the full width at half maximum (FWHM(102)) of the (102) diffraction peak at about 38.2° is about 1.05 to 1.15.

[0025] According to some embodiments of the present application, in the X-ray diffraction spectrum of the high nickel compound, the ratio FWHM(108) / FWHM(110) of the full width at half maximum (FWHM(108)) of the (108) diffraction peak at about 64.3° to the full width at half maximum (FWHM(110)) of the (110) diffraction peak at about 64.7° is about 0.95 to 1.05.

[0026] According to some embodiments of the present application, the high-nickel compound can be used as a positive electrode material for lithium-ion batteries. For example, the high-nickel compound, conductive carbon black (SP), and polyvinylidene fluoride (PVDF) binder are added to N-methylpyrrolidone (NMP) (the weight ratio of the high-nickel compound to NMP is 2.1:1) in a weight ratio of 94:3:3, and the mixture is thoroughly mixed and stirred to form a uniform slurry, thereby producing a positive electrode material (or positive electrode active material). This is then applied to an aluminum foil current collector, dried, and pressed to obtain a positive electrode plate, which can then be used to form an electrode assembly together with a negative electrode plate.

[0027] The present application also provides a battery including the electrode assembly, which may be a lithium-ion battery, which can be used in the fields of digital products, electric vehicles, or energy storage.

[0028] For example, a lithium-ion secondary battery typically comprises an electrode assembly, a non-aqueous electrolyte, a separator, and a container. Specifically, the electrode assembly may include a positive electrode plate and a negative electrode plate. The positive electrode plate may be manufactured from materials including a positive electrode current collector, a positive electrode active material coated on the positive electrode current collector, a conventional binder, a conventional conductive additive, and the like, as described above. The positive electrode active material may include the high-nickel compound proposed herein. The negative electrode is manufactured from materials including a current collector, a conventional negative electrode active material coated on the current collector, a conventional binder, a conventional conductive additive, and the like. The separator is a PP / PE film commonly used in the industry and is used to separate the positive electrode and the negative electrode from each other. The container is a housing that houses the positive electrode, the negative electrode, the separator, and the electrolyte.

[0029] When a 1 mol / L lithium hexafluorophosphate solution is used as the electrolyte, the solvent for the lithium hexafluorophosphate solution is a mixed solvent of dimethyl carbonate (DMC):ethylene carbonate (EC):diethyl carbonate (DEC) in a mass ratio of 1:1:1. The negative electrode material is a mixture of artificial graphite, conductive carbon black, carboxymethyl cellulose, and adhesive in a weight ratio of 95:1:1:3. The positive electrode plate is made from a mixture of the high-nickel compound, conductive carbon black, and PVDF in a weight ratio of 94:3:3. A cell with model number 454261 is then manufactured to finally form a battery.

[0030] A further embodiment of the present application further provides an electric device including the battery, wherein the battery is used to supply electric energy, and the electric device can include digital products, electric vehicles, energy storage devices, etc. For example, the battery can be used in portable electronic devices and electric vehicles, and can also be used in energy storage power supply systems such as hydroelectric power plants, thermal power plants, wind power plants, and solar power plants.

[0031] As people become more conscious of environmental protection, new energy sources are attracting more and more attention, and lithium-ion batteries, as one of the power batteries used in new energy vehicles, have wide application prospects.

[0032] Other embodiments of the present application further provide a method for manufacturing the high-nickel compound. This manufacturing method includes: (1) mixing a lithium source, a nickel-cobalt-manganese precursor, and an M source, and performing a first firing treatment to produce a first main material. Here, the M source is a compound containing element M, and the general formula of the first main material is Li a Ni x Co y Mn z M b O2, where 1 ≦ a ≦ 1.2, 0 < b ≦ 0.01, 0.8 ≦ x ≦ 1, 0 ≦ y < 0.12, 0 ≦ z ≦ 0.2, and x + y + z = 1; (2) mixing the first main material with an A source and performing a second firing treatment to produce a second main material. Here, the A source is a compound containing element A; and (3) mixing the second main material with a B source and performing a third firing treatment. Here, the B source is a compound containing element boron.

[0033] The general chemical formula of the second main material may be Li a Ni x Co y Mn z M b O2·cα, where α is a first coating.

[0034] Generally, the residual alkali of the high-nickel compound can be reduced by solvent washing, but this method involves problems of solvent recovery and environmental protection. On the other hand, in order to reduce or avoid the problem of solvent recovery as much as possible, the present application proposes to adopt a plurality of coating processes.

[0035] According to some embodiments of the present application, the lithium source can be selected from lithium hydroxide monohydrate. The M source is a compound containing element M, and M can be selected from one or more of the elements of Group VB and Group VIB. Exemplarily, the M source may be tantalum oxide, niobium oxide, molybdenum oxide, or tungsten oxide.

[0036] According to some embodiments of the present application, the nickel-cobalt-manganese precursor may be one or more of hydroxides, carboxylates, or oxides containing nickel, cobalt, and manganese elements, and may have a particle size of about 3 μm to 15 μm.

[0037] According to some embodiments of the present application, A may be selected from one or more of Group VB and Group VIB elements. For example, the A source may be selected from one or more of tungsten oxide, molybdenum oxide, and niobium oxide.

[0038] According to some embodiments of the present application, the B source may be selected from one or more of boric acid, lithium borate, lithium metaborate, and lithium tetraborate.

[0039] According to some embodiments of the present application, the mass ratio of the first main material to the A source is about 1.0:(0.002-0.01), for example, about 1:(0.003-0.007), and the mass ratio of the second main material to the B source is 1:(0.002-0.01), for example, about 1:(0.002-0.005).

[0040] According to some embodiments of the present application, in the above-mentioned manufacturing method, the first firing temperature is about 700 to 900°C, e.g., about 700 to 850°C, and the first firing time is about 8 to 30 hours, e.g., about 20 to 24 hours. The second firing temperature is about 500 to 800°C, e.g., about 700 to 800°C, and the second firing time is about 6 to 20 hours, e.g., about 12 to 18 hours. The third firing temperature is about 250 to 450°C, e.g., about 300 to 400°C, and the third firing time is about 3 to 15 hours, e.g., about 6 to 10 hours.

[0041] According to some embodiments of the present application, in the above manufacturing method, the first firing temperature is about 780°C, 800°C, or 840°C, and the first firing time is about 20 hours or about 24 hours. The second firing temperature is about 700°C, 740°C, or 780°C, and the second firing time is about 10 hours, 12 hours, 16 hours, or 18 hours. The third firing temperature is about 280°C, 350°C, 400°C, or 450°C, and the third firing time is about 6 hours or 8 hours.

[0042] The proposed method for producing high-nickel compounds is convenient for large-scale production. High-temperature calcination significantly reduces residual alkalinity in the high-nickel compounds, and the solvent-free process reduces or avoids environmental issues associated with solvent recovery. Furthermore, by combining it with a second coating process, the capacity of the positive electrode material can be further improved. The relatively high temperature of the first calcination process stabilizes the structure and interface. The relatively low temperatures of the second and third calcination processes inhibit side reactions between the positive electrode material and the electrolyte, reducing lithium metal loss and significantly improving the capacity of the high-nickel compounds.

[0043] Typically, cathode materials made from high-nickel compounds have a high residual alkali content, so solvent washing is the mainstream method for removing excess residual alkali. However, solvent washing leads to the waste of lithium ions, requiring the addition of more lithium salt during compounding. The proposed method for producing high-nickel compounds can effectively reduce residual alkali and repair interfacial defects by increasing the number of calcination treatments, thereby reducing or avoiding solvent washing in the process design and allowing for the addition of a relatively small amount of lithium salt during compounding. This process, combined with a specific crystal half-width ratio, can maximize the role of lithium ions, resulting in a cathode material with higher capacity and excellent gas generation performance.

[0044] The present invention will be described in detail below with reference to specific examples of the high nickel compounds and their manufacturing methods and applications. Any reagents or instruments not described in this specification are within the scope of those skilled in the art.

[0045] The reagents used in each of the following examples are shown in Table 1-1.

[0046] [Table 1-1] TIFF2025183183000003.tif175170

[0047] The equipment and analytical methods used in the following examples were as follows:

[0048] The grinding device was an SHQM type double planetary mixer manufactured by Lianyungang Chunlong Experimental Instrument Co., Ltd., and the airflow grinding device was an MX-50 airflow grinder manufactured by Yixing Juneng Grinding Equipment Co., Ltd.

[0049] In this application, the specific surface area was measured and analyzed using a fully automatic specific surface area / pore distribution measuring device (TriStar II 3020, manufactured by Micromeritics, USA).

[0050] The method for measuring free lithium in high nickel compounds was as follows.

[0051] An appropriate amount of sample (approximately 30 g) was accurately weighed to within 0.01 g. The sample was placed in a 250 mL Erlenmeyer flask, fitted with a magnetic stirrer, and 100 mL of deionized water was added. The Erlenmeyer flask was placed on a magnetic stirrer, the stirrer turned on, and the mixture was stirred for 30 minutes. The mixture was filtered using filter paper and a funnel. 50 mL of the filtrate was transferred using a 50 mL pipette into a 100 mL beaker fitted with a magnetic stir bar. The beaker was placed on a magnetic stirrer and two drops of phenolphthalein indicator were added. The solution was titrated with 0.05 mol / L hydrochloric acid standard titrant until the solution changed color from red to colorless. The volume V1 (endpoint 1) of the 0.05 mol / L hydrochloric acid standard titrant was recorded. Two drops of methyl red indicator were added, and the solution changed color from colorless to yellow. The solution was titrated with 0.05 mol / L hydrochloric acid standard titrant until the color of the solution changed from yellow to orange. The beaker was placed in a heating furnace and heated until the solution boiled (until the color of the solution changed from orange to yellow). The 100 mL beaker was removed and allowed to cool to room temperature. The beaker was placed back on the magnetic stirrer. The solution was titrated with 0.05 mol / L hydrochloric acid standard titrant until the color of the solution changed from yellow to pale red. The volume V2 (endpoint 2) of the 0.05 mol / L hydrochloric acid standard titrant was recorded. Lithium hydroxide: LiOH (wt%) = [V2-2 × (V2-V1)] × 0.05 × 23.946 × 2 × 100 / (m × 1000), lithium carbonate: Li2CO3 (wt%) = (V2-V1) × 0.05 × 73.886 × 2 × 100 / (m × 1000), free lithium: Li + (wt%)=V2×0.05×6.94×2×100 / (m×1000).

[0052] Measurement of average particle size: Measurement was carried out using an MS3000 laser particle size analyzer, and the method was as follows.

[0053] An appropriate amount of sample was placed in a 100 mL beaker, first rinsing the beaker's inner wall with a wash bottle, then rinsing any sample adhering to the bottom of the beaker with the wash bottle. The amount of pure water added to the beaker was controlled at 20-30 mL, and the ultrasonic time was 5 min (10 s of stirring before, during, and after sonication, respectively, at a stirring speed of approximately 2 r / s). 100 ± 10 mL of pure water was added to the sampler of the MS3000 laser particle size analyzer, the rotation speed was adjusted to 3000 r / min, and the stat button was pressed. The instrument automatically aligned the optical axis, performed background measurements, and waited for instructions. After sonication, the sample was transferred to the stirring tank, and the beaker was rinsed with a wash bottle to ensure all sample had been transferred. Once all sample had been added, the software automatically began measurement. Data was automatically saved upon completion.

[0054] X-ray diffraction measurement method: Measurements were performed using a pert PRU X-ray diffractometer manufactured by PANalytical in the Netherlands, with Cu- as the X-ray source and the diffraction angle set to 10 to 80°.

[0055] The method for manufacturing a battery (cell model number 454261) using the high nickel compound produced in this application was as follows.

[0056] Preparation of positive electrode plate: The proposed high-nickel compound, conductive carbon black (SP), and binder polyvinylidene fluoride (PVDF) were added to N-methylpyrrolidone (NMP) (the weight ratio of high-nickel compound to NMP was 2.1:1) in a weight ratio of 94:3:3, thoroughly mixed and stirred to form a uniform slurry, which was then applied to an aluminum foil current collector, dried, and pressed into a plate.

[0057] Preparation of negative electrode plate: Negative electrode artificial graphite, conductive carbon black (SP), carboxymethyl cellulose (CMC), and adhesive (SBR) were mixed in a weight ratio of 95:1:1:3 with sufficient amount of pure water, stirred to form a uniform slurry, applied to a copper foil current collector, dried, and pressed into a plate.

[0058] The separator was a three-layer composite film material of PP / PE / PP.

[0059] Tabs were spot welded to the pressed positive and negative plates, a separator was inserted, the resultant was wound up with a winder and loaded into a soft pack fixture, the top and side were sealed, and the resultant was then placed in an oven to dry. Subsequently, 9 g of electrolyte was injected in an environment with a relative humidity of less than 1.5%, and the resultant was subjected to 48 hours of chemical formation (Zhejiang Hangzhou Co., Ltd. LIP-3AHB06 high-temperature chemical formation system), after which it was vacuum sealed.

[0060] Sample drying and high-temperature battery testing were performed using a KPBAK-03E-02 high-efficiency vacuum drying box manufactured by Dongguan Keyuan Mechanical & Electrical.

[0061] Charge-discharge tests of the lithium-ion secondary batteries manufactured in this study were conducted using a Wuhan BlueElectron battery tester (Wuhan BlueElectron CT2001C tester) in accordance with the test method of GB / T 18287-2000. Different battery systems significantly affected the cycle retention rate of materials. The battery system used in the experiments was a common evaluation system. The electrolyte was a 1 mol / L lithium hexafluorophosphate solution, and the solvent for the lithium hexafluorophosphate solution was a dimethyl carbonate (DMC):ethylene carbonate (EC):diethyl carbonate (DEC) mixed solvent with a mass ratio of 1:1:1. The anode material was a mixture of artificial graphite, conductive carbon black, carboxymethyl cellulose, and adhesive in a weight ratio of 95:1:1:3. The cell model number was 454261. This allowed for early identification of actual defects in the cathode material and confirmation of the cathode material's performance.

[0062] Example 1 According to the molar ratio of Li:(Ni+Co+Mn):Nb = 1.03:1:0.004, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 92:05:03, was used. 0.92 Co 0.05 Mn 0.03(OH)2) and nano-niobium pentoxide powder were added and ball-milled. The mixture was then ball-milled at 40 Hz for 10 minutes to homogenize and then discharged (mixed material). This mixture was placed in a muffle furnace and heated to 780°C at a heating rate of 5°C / min under an oxygen atmosphere. After sintering for 24 hours, it was cooled to room temperature and ball-milled at 40 Hz for 10 minutes to obtain the first primary material. Then, a corresponding amount of tungsten oxide was weighed and added to the first primary material so that the mass ratio of the first primary material to tungsten oxide was 1.0:0.0028. This mixture was then ball-milled at 40 Hz for 10 minutes. The homogenized mixture was placed in a muffle furnace and heated to 700°C at a heating rate of 10°C / min under an oxygen atmosphere. After sintering for 18 hours (second sintering), it was cooled to room temperature. The sample after the second sintering was crushed to obtain the second primary material. Next, the corresponding amount of boric acid was weighed and added to the second main material so that the mass ratio of the second main material to boric acid was 1.0:0.0025, and the mixture was ball-milled at a rotation speed of 40 Hz for 10 minutes. The homogeneously mixed material was placed in a muffle furnace and heated to 350°C at a heating rate of 5°C / min in an air atmosphere. After sintering for 6 hours, the mixture was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain high-nickel compound 1.

[0063] When the particle size of the high-nickel compound 1 was measured, the average particle size of the primary particles was 10.5 μm.

[0064] The high nickel compound 1 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0065] The elemental composition of high nickel compound 1 was analyzed and the test data is shown in Table 1. The final chemical formula of the high nickel compound is Li 1.03 Ni 0.92 Co 0.05 Mn 0.03 Nb 0.004 O2·0.0012WO30.004 Li3BO3.

[0066] The method for measuring the element contents was as follows.

[0067] A 0.2000 g sample (accurate to 0.0001 g) was accurately weighed and placed in a clean 100 mL glass beaker. 10 mL (1:1) of aqua regia solution was added to the beaker (a blank experiment was also performed simultaneously), covered with a watch glass, and placed on a hot plate. The solution was heated until nearly dry. The heating was stopped, the beaker was removed, and the beaker was allowed to cool to room temperature. The watch glass and the side walls of the beaker were rinsed with deionized water at least three times. The entire solution was then transferred to a 50 mL volumetric flask, brought to volume with deionized water, and shaken thoroughly. A 1 mL portion of the sample was pipetted into a 100 mL volumetric flask, brought to volume, and shaken thoroughly. The above solution was measured using an inductively coupled plasma optical emission spectrometer (ICP-OES, Thermo Fisher Scientific, USA / ICAP7400) according to Part 1 of YS / T 1006.2-2014.

[0068] [Table 1]

[0069] Example 2 According to the molar ratio of Li:(Ni+Co+Mn):Ta = 1.10:1:0.003, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 93:03:04, was used. 0.93 Co 0.03 Mn 0.04(OH)2) and nano-tantalum oxide powder were ball-milled and then ball-milled at 40 Hz for 10 minutes. The mixture was uniformly mixed and then discharged (mixed material). This mixture was placed in a muffle furnace, heated to 800°C at a heating rate of 5°C / min under an oxygen atmosphere, sintered for 20 hours, cooled to room temperature, ball-milled at 40 Hz for 10 minutes, and then air-flow pulverized to obtain the first primary material. Molybdenum oxide was then weighed and added to the first primary material so that the mass ratio of the first primary material to molybdenum oxide was 1.0:0.003. This mixture was then ball-milled at 40 Hz for 10 minutes. The uniformly mixed material was placed in a muffle furnace, heated to 700°C at a heating rate of 10°C / min under an oxygen atmosphere, sintered for 12 hours (second sintering), and then cooled to room temperature. The sample after the second sintering was then pulverized to obtain the second primary material. Next, the corresponding amount of lithium borate was weighed and added to the main material 2 so that the mass ratio of the second main material to lithium borate was 1.0:0.005, and the mixture was ball milled at a rotation speed of 40 Hz for 10 minutes. The homogeneously mixed material was placed in a muffle furnace and heated to 450°C at a heating rate of 5°C / min in an air atmosphere. After sintering for 8 hours, the mixture was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain high-nickel compound 2.

[0070] When the particle size of the high-nickel compound 2 was measured, the average particle size of the primary particles was 3.8 μm.

[0071] The high nickel compound 2 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0072] The elemental composition of high nickel compound 2 was analyzed and the test data is shown in Table 2. The final chemical formula of the high nickel compound is Li 1.10 Ni 0.93 Co 0.03 Mn 0.04 Ta 0.003 O2·0.002MoO30.008 Li3BO3.

[0073] The method for measuring the element contents was as follows.

[0074] A 0.2000 g sample (accurate to 0.0001 g) was accurately weighed and placed in a clean 100 mL glass beaker. 10 mL (1:1) of aqua regia solution was added to the beaker (a blank experiment was also performed simultaneously), covered with a watch glass, and placed on a hot plate. The solution was heated until nearly dry. The heating was stopped, the beaker was removed, and the beaker was allowed to cool to room temperature. The watch glass and the side walls of the beaker were rinsed with deionized water at least three times. The entire solution was then transferred to a 50 mL volumetric flask, brought to volume with deionized water, and shaken thoroughly. A 1 mL portion of the sample was pipetted into a 100 mL volumetric flask, brought to volume, and shaken thoroughly. The above solution was measured using an inductively coupled plasma optical emission spectrometer (ICP-OES, Thermo Fisher Scientific, USA / ICAP7400) according to Part 1 of YS / T 1006.2-2014.

[0075] [Table 2]

[0076] Example 3 According to the molar ratio of Li:(Ni+Co+Mn):W = 1.2:1:0.002, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 83:07:10, was used. 0.83 Co 0.07 Mn 0.10(OH)2) and nano-tungsten oxide powder were ball-milled and then ball-milled at 40 Hz for 10 minutes. After uniform mixing, the mixture was discharged (mixed material). This mixture was placed in a muffle furnace and heated to 840°C at a heating rate of 5°C / min under an oxygen atmosphere. After sintering for 24 hours, it was cooled to room temperature and ball-milled at 40 Hz for 10 minutes. The first primary material was obtained by ball-milling the corresponding amount of niobium oxide to achieve a mass ratio of 1.0:0.0067. The resulting mixture was then ball-milled at 40 Hz for 10 minutes. The resulting mixture was then placed in a muffle furnace and heated to 780°C at a heating rate of 10°C / min under an oxygen atmosphere. After sintering for 18 hours (second sintering), it was cooled to room temperature. The sample after the second sintering was then pulverized to obtain the second primary material. Next, the corresponding amount of lithium metaborate was weighed and added to the main material 2 so that the mass ratio of the second main material to lithium metaborate was 1.0:0.004, and the mixture was ball-milled at a rotation speed of 40 Hz for 10 minutes. The homogeneously mixed material was placed in a muffle furnace and heated to 400°C at a heating rate of 5°C / min in an air atmosphere. After sintering for 8 hours, the mixture was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain high-nickel compound 3.

[0077] When the particle size of the high-nickel compound 3 was measured, the average particle size of the primary particles was 4.2 μm.

[0078] The high nickel compound 3 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0079] The elemental composition of high nickel compound 3 was analyzed and the test data is shown in Table 3. The final chemical formula of the high nickel compound is Li 1.2 Ni 0.83 Co 0.07 Mn 0.10 W 0.002 O2·0.0025Nb2O50.008 LiBO2.

[0080] The method for measuring the element contents was as follows.

[0081] A 0.2000 g sample (accurate to 0.0001 g) was accurately weighed and placed in a clean 100 mL glass beaker. 10 mL (1:1) of aqua regia solution was added to the beaker (a blank experiment was also performed simultaneously), covered with a watch glass, and placed on a hot plate. The solution was heated until nearly dry. The heating was stopped, the beaker was removed, and the beaker was allowed to cool to room temperature. The watch glass and the side walls of the beaker were rinsed with deionized water at least three times. The entire solution was then transferred to a 50 mL volumetric flask, brought to volume with deionized water, and shaken thoroughly. A 1 mL portion of the sample was pipetted into a 100 mL volumetric flask, brought to volume, and shaken thoroughly. The above solution was measured using an inductively coupled plasma optical emission spectrometer (ICP-OES, Thermo Fisher Scientific, USA / ICAP7400) according to Part 1 of YS / T 1006.2-2014.

[0082] [Table 3]

[0083] Example 4 According to the molar ratio of Li:(Ni+Co+Mn):Mo = 1.06:1:0.003, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 83:07:10, was used. 0.83 Co 0.07 Mn 0.1(OH)2) and nano-molybdenum oxide powder were ball-milled and then ball-milled at 40 Hz for 10 minutes. After uniform mixing, the mixture was discharged (mixed material). This mixture was placed in a muffle furnace and heated to 800°C at a heating rate of 5°C / min under an oxygen atmosphere. After sintering for 24 hours, it was cooled to room temperature and ball-milled at 40 Hz for 10 minutes to obtain the first primary material. Then, a corresponding amount of tungsten oxide was weighed and added to the first primary material so that the mass ratio of the first primary material to tungsten oxide was 1.0:0.0047. This mixture was then ball-milled at 40 Hz for 10 minutes. The resulting mixture was placed in a muffle furnace and heated to 740°C at a heating rate of 10°C / min under an oxygen atmosphere. After sintering for 18 hours (second sintering), it was cooled to room temperature. The sample after the second sintering was crushed to obtain the second primary material. Next, the corresponding amount of lithium tetraborate was weighed and added to the second main material so that the mass ratio of the second main material to lithium tetraborate was 1.0:0.0043, and the mixture was ball-milled at a rotation speed of 40 Hz for 10 minutes. The homogeneously mixed material was placed in a muffle furnace and heated to 280°C at a heating rate of 5°C / min in an air atmosphere. After sintering for 8 hours, the mixture was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain high-nickel compound 4.

[0084] When the particle size of the high-nickel compound 4 was measured, the average particle size of the primary particles was 10.5 μm.

[0085] The high nickel compound 4 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0086] The elemental composition of high nickel compound 4 was analyzed and the test data is shown in Table 4. The final chemical formula of the high nickel compound is Li 1.08 Ni 0.83 Co 0.07 Mn 0.10 Mo 0.003 O2·0.002WO30.0025 Li2B4O7.

[0087] [Table 4]

[0088] Example 5 According to the molar ratio of Li:(Ni+Co+Mn):Nb = 1.1:1:0.001, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 87:05:08, was used. 0.87 Co 0.05 Mn 0.08 (OH)2) and nano-niobium oxide powder were added and ball-milled. The mixture was ball-milled at 40 Hz for 10 minutes, uniformly mixed, and then discharged (mixed material). This mixture was placed in a muffle furnace, heated to 780°C at a heating rate of 5°C / min under an oxygen atmosphere, sintered for 20 hours, cooled to room temperature, and ball-milled at 40 Hz for 10 minutes to obtain the first main material. Then, the corresponding amount of tungsten oxide was weighed and added to the first main material so that the mass ratio of the first main material to tungsten oxide was 1.0:0.0047. This mixture was ball-milled at 40 Hz for 10 minutes. The uniformly mixed material was placed in a muffle furnace, heated to 700°C at a heating rate of 10°C / min under an oxygen atmosphere, sintered for 16 hours (second sintering), and then cooled to room temperature. The sample after the second sintering was pulverized to obtain the cathode main material 2. Next, the corresponding amount of boric acid was weighed and added to the main material 2 so that the mass ratio of the main material 2 to the boric acid was 1.0:0.0048, and the mixture was ball milled at a rotation speed of 40 Hz for 10 minutes. The homogeneously mixed material was placed in a muffle furnace and heated to 350°C at a heating rate of 5°C / min in an air atmosphere. After sintering for 6 hours, the mixture was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain high-nickel compound 5.

[0089] When the particle size of the high-nickel compound 5 was measured, the average particle size of the primary particles was 11.2 μm.

[0090] The high nickel compound 5 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0091] The elemental composition of high nickel compound 5 was analyzed and the test data is shown in Table 5. The final chemical formula of the high nickel compound is Li 1.1 Ni 0.87 Co 0.05 Mn 0.08 Nb 0.001 O2·0.002WO30.006 Li3BO3.

[0092] [Table 5]

[0093] Comparative Example 1 According to the molar ratio of Li:(Ni+Co+Mn):Nb = 1.12:1:0.002, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 83:07:10, was used. 0.83 Co 0.07 Mn 0.1 (OH)2) and nano-niobium oxide powder were ball-milled at 40 Hz for 10 minutes, mixed uniformly, and then discharged (mixed material). This mixed material was placed in a muffle furnace and heated to 860°C at a heating rate of 5°C / min under an oxygen atmosphere. Sintered for 24 hours, cooled to room temperature, ball-milled at 40 Hz for 10 minutes, and then air-flow crushed to obtain the first main material. Next, water and the main material were added sequentially so that the mass ratio of water, first main material, and tungsten oxide was 1.5:1.0:0.007. Mixed and stirred for 10 minutes, tungsten oxide was added, and the mixture was stirred for 10 minutes. The mixture was then suction filtered and dried at 120°C. The dried sample was heated to 780°C at a heating rate of 10°C / min under an oxygen atmosphere and sintered for 10 hours (second sintering), after which it was cooled to room temperature. The sample after the second sintering was crushed and sieved through a 300 mesh metal sieve to obtain a high-nickel compound D1.

[0094] When the particle size of the high-nickel compound D1 was measured, the average particle size of the primary particles was 3.4 μm.

[0095] The high nickel compound D1 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0096] The elemental composition of the high nickel compound D1 was analyzed and the test data is shown in Table 6. The final chemical formula of the cathode material is Li 1.12 Ni 0.83 Co 0.07 Mn 0.10 Nb 0.002 The value was O2·0.003WO3.

[0097] [Table 6]

[0098] Comparative Example 2 According to the molar ratio of Li:(Ni+Co+Mn):W = 1.06:1:0.001, lithium hydroxide monohydrate, a precursor (chemical formula: Ni) with a molar ratio of Ni:Co:Mn = 83:07:10, was used. 0.83 Co 0.07 Mn 0.1 (OH)2) and nano-tungsten oxide powder were added and ball-milled at 40 Hz for 10 minutes. After uniform mixing, the mixture was discharged (mixed material). This mixture was placed in a muffle furnace and heated to 780°C at a heating rate of 5°C / min under an oxygen atmosphere. After sintering for 24 hours, it was cooled to room temperature and ball-milled at 40 Hz for 10 minutes to obtain the first main material. Next, the corresponding amount of boric acid was weighed and added to Main Material 1 so that the mass ratio of the first main material to boric acid was 1.0:0.0043. This mixture was then ball-milled at 40 Hz for 10 minutes. The uniformly mixed material was placed in a muffle furnace and heated to 320°C at a heating rate of 5°C / min under an air atmosphere. After sintering for 8 hours, it was cooled to room temperature and sieved through a 300-mesh metal sieve to obtain the high-nickel compound D2.

[0099] When the particle size of the high-nickel compound D2 was measured, the average particle size of the primary particles was 9.6 μm.

[0100] The high nickel compound D2 was subjected to specific surface area measurement, X-ray diffraction and cycle testing, and the data are shown in Table 8.

[0101] The elemental composition of the high nickel compound D2 was analyzed and the test data are shown in Table 7. The final chemical formula of the cathode material is Li 1.06 Ni 0.83 Co 0.07 Mn 0.10 W 0.001 O2·0.0025 Li2B4O7.

[0102] [Table 7]

[0103] [Table 8]

[0104] As shown in Table 8, the high nickel compounds prepared in the above examples of the present application have a total free lithium content of less than 1500 ppm and a specific surface area of ​​0.3 to 0.9 m 2 / g range, particle size ranged from 3.0 to 12 μm, FWHM(006) / FWHM(102) ratios were 1.05 to 1.15, and FWHM(108) / FWHM(110) ratios were 0.95 to 1.05, and the structure and interface were stable, and the particles were relatively stable in air.

[0105] As can be seen from Table 8, when the Ni mole fraction in the example was 0.83, the capacity of the positive electrode material was 198.1 mAh / g, compared with only 191.5 mAh / g for the conventional water washing process (Comparative Example 1). Although the cycles were essentially the same, the gas generation performance was significantly superior. When the Ni mole fraction exceeded 0.9, the capacity reached 206.2 mAh / g, providing a basis for the future application of high-nickel compound products. Furthermore, the gas generation performance of the positive electrode material produced by the proposed high-nickel compound and its manufacturing process was improved over that of materials manufactured using existing processes.

[0106] Although the technical contents and technical features of the present application have been disclosed above, those skilled in the art can make various substitutions and modifications based on the teachings and disclosures of the present application without departing from the spirit of the present application. Therefore, the scope of protection of the present application is not limited to the contents disclosed in the embodiments, but includes various substitutions and modifications that do not depart from the gist of the present application and are encompassed within the scope of the claims of the present application.

Claims

1. A high nickel compound with the general chemical formula Li ａ Ni ｘ Co ｙ Mn ｚ M ｂ O ２ cα and dβ, where 1.03≦a≦1.2, 0.001≦b≦0.004, 0.0012≦c≦0.003, 0.0025≦d≦0.008, 0.8≦x≦1, 0≦y<0.12, 0≦z≦0.2, and x+y+z=1; M is a doping element; α is the first coating; β is the second coating; M is selected from one or more of group VB and group VIB elements; and α is V. A high nickel compound selected from compounds containing one or more of Group B and Group VIB elements, wherein β is selected from one or more of boric acid, lithium borate, lithium metaborate, lithium tetraborate, and other boron-containing compounds, or β is formed from one or more of boric acid, lithium borate, lithium metaborate, lithium tetraborate, and other boron-containing compounds.

2. 10. The high nickel compound of claim 1, wherein the high nickel compound contains less than 1500 ppm of total free lithium.

3. The specific surface area of ​​the high nickel compound is 0.1 to 1.5 m ２ / g and the average particle size is 2 to 15 μm.

4. 2. The high nickel compound according to claim 1, wherein in an X-ray diffraction spectrum of the high nickel compound, the ratio FWHM(006) / FWHM(102) of the full width at half maximum of a (006) diffraction peak at about 37.9° to the full width at half maximum of a (102) diffraction peak at about 38.2° is 1.05 to 1.

15.

5. 2. The high nickel compound according to claim 1, wherein in an X-ray diffraction spectrum of the high nickel compound, the ratio FWHM(108) / FWHM(110) of the full width at half maximum (FWHM(108)) of a (108) diffraction peak at about 64.3° to the full width at half maximum (FWHM(110)) of a (110) diffraction peak at about 64.7° is 0.95 to 1.

05.

6. A positive electrode plate comprising a positive electrode current collector and a positive electrode active material comprising the high nickel compound of any one of claims 1 to 5.

7. An electrode assembly comprising: a negative electrode plate including a negative electrode current collector and a negative electrode active material disposed on the negative electrode current collector; and the positive electrode plate of claim 6 .

8. A battery comprising the electrode assembly of claim 7.

9. 10. An electrical device comprising the battery of claim 8 used to supply electrical energy.

10. A method for producing a high nickel compound, comprising: (1) Mixing a lithium source, a nickel-cobalt-manganese precursor, and an M source, and performing a first calcination process to prepare a first main material, wherein the M source is a compound containing element M, and the general formula of the first main material is Li ａ Ni ｘ Co ｙ Mn ｚ M ｂ O ２ , 1.03≦a≦1.2, 0.001≦b≦0.004, 0.8≦x≦1, 0≦y<0.12, 0≦z≦0.2, x+y+z=1; (2) mixing the first main material with an A source and performing a second calcination process to produce a second main material, wherein the A source is a compound containing element A; and (3) Mixing the second main material with a B source and performing a third firing process, wherein the B source is a compound containing elemental boron. Including, wherein the element M is selected from one or more of the group VB and group VIB elements, and / or the element A is selected from one or more of the group VB and group VIB elements.

11. The method according to claim 10, wherein the mass ratio of the first main material to the A source is 1:(0.002-0.01).

12. The method according to claim 10, wherein the mass ratio of the first main material to the A source is 1:(0.003-0.007).

13. The method according to claim 10, wherein the mass ratio of the second primary material to the B source is 1:(0.002-0.01).

14. The method according to claim 10, wherein the mass ratio of the second primary material to the B source is 1:(0.002-0.005).

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