Ternary material precursor and ternary material prepared therefrom

Abstract

The invention belongs to the field of lithium-ion batteries. Provided are a ternary material precursor and a ternary material prepared therefrom. By limiting several parameters of the ternary material precursor, including the specific surface area thereof, the peak intensity ratio I001 / I101 of crystal diffraction characteristic peaks, the length-width ratio of whiskers, the true density and the internal porosity, higher quality stability and electrochemical performance can be obtained when the ternary material precursor is subsequently used for preparing a ternary material, especially a single-crystal ternary material.

Description

A ternary material precursor and ternary material prepared therefrom Technical Field

[0001] This article relates to the field of lithium-ion batteries, and specifically to a ternary material precursor and a ternary material prepared therefrom. Background Art

[0002] In recent years, with the rapid development of electric vehicles and large-scale energy storage markets, the output of ternary lithium-ion power batteries, which currently occupy the largest market share, has also grown rapidly. In order to improve the endurance of ternary positive electrode materials, people have tried to increase the nickel content of the material and construct high-nickel single-crystal ternary materials.

[0003] The properties of traditional high-nickel polycrystalline ternary materials are relatively stable. The main reason is that most of their physical properties are directly inherited from the precursor material. However, high-nickel single-crystal ternary materials need to destroy the secondary agglomerated spherical morphology of the precursor material during the preparation process in order to obtain primary grains. At the same time, even if the precursor material is prepared using the same process, the physical properties of different batches of products are different. Therefore, the performance of the prepared products is relatively random and cannot be effectively controlled. Relevant researchers have tried to control the structure of the precursor material and construct a core-shell structure precursor material with gradient porosity for the preparation of the final product to achieve performance control. However, this solution has high requirements for process and equipment and is difficult to achieve industrialization. Others have tried to directly monitor the thermal conductivity of the final product, the intensity of the D104 characteristic peak in XRD, and the parameters of porosity construction to achieve electrochemical performance control. However, this method does not actually improve the product itself and can only be used as a product screening method.

[0004] Summary of the Invention

[0005] Based on the defects of related technologies, the purpose of this article is to provide a ternary material precursor. By limiting its specific surface area, crystal diffraction characteristic peak I001 / 101 peak intensity ratio, whisker aspect ratio, true density and internal porosity, the precursor material can obtain higher quality stability and electrochemical performance when subsequently used to prepare ternary materials, especially single crystal ternary materials.

[0006] In order to achieve the above objectives, the technical solutions adopted in this paper are:

[0007] A ternary material precursor with the molecular formula Ni a Co b M 1-a-b (OH)2, wherein 0.8≤a≤1, 0≤b≤0.1, and M is at least one of Mn, Al, Mg, Ti, Zr, and W;

[0008] The specific surface area of ​​the ternary material precursor is 5 to 30 m2 / g, I001 / I101 peak intensity ratio is 0.6-2.5, average whisker aspect ratio is 2-50, and true density is 3.4-4.0g / cm 3 , the internal porosity is 1.5~5.0%.

[0009] In one embodiment, the I001 / I101 peak intensity ratio is the peak intensity ratio of the I001 characteristic peak to the I101 characteristic peak in the X-ray diffraction pattern of the ternary material precursor.

[0010] In one embodiment, the average aspect ratio of the whiskers is an average value of the ratio of the length to the width of the primary particles in the secondary agglomerated particles of the ternary material precursor under a scanning electron microscope obtained by using microscopic analysis software.

[0011] In one embodiment, the internal porosity is the average value of the ratio of the cross-sectional hole area to the full cross-sectional area obtained by microscopic analysis software under a scanning electron microscope after the secondary agglomerated particles of the ternary material precursor are cut by an ion beam.

[0012] In the related art, the ternary material precursors prepared by different processes have great differences in morphology, element proportion, crystal structure and physical properties. These different materials are uncontrollable when used to prepare ternary materials. However, the ternary material precursors within the five parameter ranges described in the scheme of this article can be obtained without the use of special process conditions. The material properties are stable and are directly related to the secondary morphology and properties of the prepared ternary materials, especially single crystal ternary materials. Therefore, the prepared products have high quality stability, good structural stability, and excellent electrochemical charge and discharge performance and cycle performance.

[0013] In one embodiment, the capacity coefficient R of the ternary material precursor satisfies 0.1≤R≤1, and the R capacity coefficient satisfies the following relationship:

[0014] Wherein B is the specific surface area of ​​the ternary material precursor, X is the I001 / I101 peak intensity ratio of the ternary material precursor, F is the average aspect ratio of the whiskers of the ternary material precursor, ρ is the true density of the ternary material precursor, and δ is the internal porosity of the ternary material precursor.

[0015] Experimental verification shows that when the specific surface area, crystal diffraction characteristic peak I001 / 101 peak intensity ratio, whisker aspect ratio, true density and internal porosity of the ternary material precursor are within the range of the scheme of this article, and the capacity coefficient R will be maintained within the above range, the ternary material prepared using the ternary material precursor, especially the single crystal ternary material, has excellent electrochemical activity and high specific capacity.

[0016] In one embodiment, the capacity coefficient R satisfies 0.3≤R≤0.9.

[0017] When the above range is met, the probability that the ternary material finally prepared has a higher discharge capacity is higher when the ternary material precursor has the same chemical composition.

[0018] Another object of this article is to provide a ternary material prepared from the ternary material precursor described in this article.

[0019] Another object of this invention is to provide a method for preparing the ternary material, comprising the following steps:

[0020] (1) mixing the ternary material precursor with a lithium source and a doping metal source, and then calcining at 750-850°C in an oxygen atmosphere. The resulting particles are crushed, sieved, and crushed again to obtain single crystal powder;

[0021] (2) mixing a soluble lithium source and a doping metal source in deionized water, adding the single crystal powder to the resulting mixture while stirring and mixing for 0.5 to 5 minutes, followed by centrifugal dehydration and drying to obtain a modified coated powder;

[0022] (3) mixing the boron source and the modified coated powder, and then calcining at 280-320° C. in an oxygen atmosphere to obtain the ternary material;

[0023] The doping metal source is at least one of a zirconium source, a molybdenum source, a chromium source, a tungsten source, and an aluminum source.

[0024] In the preparation method of the ternary material described in this article, a specific sintering temperature environment is selected to prepare the single crystal powder according to the physical properties of the ternary material precursor. After two crushings, the prepared single crystal powder can have the expected better performance.

[0025] In one embodiment, the ternary material is a single crystal ternary material.

[0026] In one embodiment, the single crystal ternary material is Li x Ni a Co b M c N 1-a-b-c O2, wherein 0.8≤a≤1, 0≤b≤0.1, 0.001≤c≤0.01, M is at least one of Mn, Al, Mg, Ti, Zr, and W, and N is at least one of Zr, Mo, Ge, W, and Al.

[0027] In the preparation method of the ternary material described in this article, when the single crystal powder is in situ coated and modified in a mixed solution containing a lithium-rich compound, the surface of the single crystal powder can not only form a lithium-rich fast ion conductor, further promoting ion diffusion and reducing capacity loss, but also reduce the amount of residual lithium on the surface. Ultimately, under the unique primary particle structure of the single crystal, the product can exhibit good charge and discharge stability.

[0028] In one embodiment, the lithium source is LiOH, and the doping metal source mixed with the lithium source and the ternary material precursor to prepare the single crystal powder is a zirconium source, and the zirconium source is at least one of ZrO2, Li2ZrO3, Zr(OH)4, and ZrF4; the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in the lithium source, and the molar amount of zirconium atoms in the zirconium source is: n(Ni+Co+M):n(Li):n(Zr)=1:(1.01~1.06):(0.001~0.01).

[0029] In one embodiment, the D003 grain size of the particles after primary crushing is 50-62 nm.

[0030] In one embodiment, the D003 grain size of the particles after the first crushing is 50-60 nm.

[0031] In one embodiment, the particle size D of the particles after secondary crushing is 50 2.5~4μm.

[0032] In one embodiment, the soluble lithium source is a mixture of LiOH and Li2CO3, wherein the concentration of LiOH in the mixture is 0.5-1.5 mol / L, and the concentration of Li2CO3 is 0.2-0.8 mol / L.

[0033] In one embodiment, the doping metal source mixed with the soluble lithium source is a molybdenum source and a chromium source, the molybdenum source is at least one of Mo2O3, H2MoO4, and (NH4)2MoO4, and the chromium source is at least one of GeO2, H2GeO4, and Ge(OH)4; the molar ratio of molybdenum atoms in the molybdenum source to chromium atoms in the chromium source is (1 to 10):1.

[0034] In one embodiment, the single crystal powder and the mixed liquid are mixed in a mass ratio of (0.5-0.7):1.

[0035] In one embodiment, the solid content of the slurry obtained by centrifugal dehydration is 8-15 wt %.

[0036] In one embodiment, the drying temperature is 140-180° C., and the drying time is 3-8 hours.

[0037] In one embodiment, the boron source is at least one of B2O3, H3BO3, Li3BO3, LiBO2, CoB, Li2B4O7, and LiB5O8.

[0038] In one embodiment, the mass ratio of the boron source to the modified coated powder is 1:(50-400).

[0039] In this paper's proposal, the single crystal ternary material prepared by the above method has a higher capacity than products prepared by other methods.

[0040] Another object of this article is to provide a lithium-ion battery positive electrode plate, including the ternary material described in this article.

[0041] Another object of this invention is to provide a lithium-ion battery comprising the lithium-ion battery positive electrode sheet described herein.

[0042] The beneficial effect of this article is that it provides a ternary material precursor. By limiting its specific surface area, crystal diffraction characteristic peak I001 / 101 peak intensity ratio, whisker aspect ratio, true density, and internal porosity, this precursor material can achieve higher quality stability and electrochemical performance when subsequently used to prepare ternary materials, especially single-crystal ternary materials. This article also provides ternary materials, especially single-crystal ternary materials, prepared using the ternary material precursor. Such products not only have excellent batch quality stability but also exhibit ideal electrochemical capacity and cycling stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a scanning electron microscope image of the ternary material precursor described in Example 1-1 of this article.

[0044] Figure 2 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Example 1-1 of this article.

[0045] Figure 3 is a scanning electron microscope image of the ternary material precursor described in Examples 1-2 of this article.

[0046] Figure 4 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Examples 1-2 of this document.

[0047] Figure 5 is a scanning electron microscope image of the ternary material precursor described in Examples 1-3 of this article.

[0048] Figure 6 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Examples 1-3 of this document.

[0049] Figure 7 is a scanning electron microscope image of the ternary material precursor described in Example 2-1 of this article.

[0050] FIG8 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Example 2-1 of this document.

[0051] Figure 9 is a scanning electron microscope image of the ternary material precursor described in Example 2-2 of this article.

[0052] Figure 10 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Example 2-2 of this article.

[0053] Figure 11 is a scanning electron microscope image of the ternary material precursor described in Examples 2-3 of this article.

[0054] Figure 12 is a scanning electron microscope image of a cross section of secondary particles required for determining the internal porosity of the ternary material precursor described in Examples 2-3 of this document. DETAILED DESCRIPTION

[0055] In order to better illustrate the purpose, technical solutions and advantages of this invention, the invention will be further described below in conjunction with specific examples and comparative examples, the purpose of which is to provide a detailed understanding of the contents of this invention, rather than to limit this invention. The experimental reagents and instruments involved in the implementation of this invention are all commonly used reagents and instruments unless otherwise specified.

[0056] The ternary material precursor described herein has no specific restrictions on the preparation process and can be prepared by the following steps:

[0057] According to the expected element molar ratio, the Ni source, the Co element in the Co source and the Mn source are prepared into a mixed metal solution and introduced into a reactor. At the same time, sodium hydroxide and ammonia solution are added for co-precipitation. Finally, the ternary precursor is obtained by centrifugation, water washing and drying.

[0058] In one embodiment, the concentration of the mixed metal solution is 1.8 to 2.0 mol / L, the flow rate in the reactor is 40 to 60 L / h, and the flow rate of the ammonia solution is 1 to 5 L / h; the sodium hydroxide is added in the form of a solution, the solute mass concentration of the sodium hydroxide solution is 25 to 40%, the solution flow rate in the reactor is 10 to 30 L / h, the temperature in the reactor during coprecipitation is 60 to 80° C., and the pH is 9 to 11.5.

[0059] In one embodiment, the ternary precursor material is Ni 0.82 Co 0.06 Mn 0.12 (OH) 2, the preparation method comprises the following steps:

[0060] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 82:6:12 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni. 0.82 Co 0.06 Mn 0.12 (OH)2;

[0061] In one embodiment, the ternary material precursor is Ni 0.94 Co 0.04 Mn 0.02 (OH) 2, the preparation method comprises the following steps:

[0062] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 94:4:2 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni 0.94 Co 0.04 Mn 0.02 (OH)2;

[0063] In one embodiment, the ternary material precursor is Ni 0.88 Co 0.06 Mn 0.06 (OH) 2, the preparation method comprises the following steps:

[0064] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 88:6:6 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni. 0.88 Co 0.06 Mn 0.06 (OH)2;

[0065] In one embodiment, the ternary material precursor is Ni 0.92 Co 0.05 Mn 0.03 (OH) 2, the preparation method comprises the following steps:

[0066] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 92:5:3 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni. 0.92 Co0.05 Mn 0.03 (OH)2;

[0067] In one embodiment, the ternary material precursor is Ni 0.82 Co 0.06 Mn 0.12 (OH) 2, the preparation method comprises the following steps:

[0068] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 82:6:12 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni. 0.82 Co 0.06 Mn 0.12 (OH)2;

[0069] In one embodiment, the ternary material precursor is Ni 0.94 Co 0.04 Mn 0.02 (OH) 2, the preparation method comprises the following steps:

[0070] Ni source, Co source and Mn source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 94:4:2 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni 0.94 Co 0.04 Mn 0.02 (OH)2;

[0071] In one embodiment, the ternary material precursor is Ni 0.90 Co 0.05 Al 0.05 (OH) 2, the preparation method comprises the following steps:

[0072] Ni source, Co source and Al source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Al element in Al source of 94:4:2 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni 0.94 Co 0.04 Mn 0.02 (OH)2;

[0073] In one embodiment, the ternary material precursor is Ni 0.98 Co 0.01 Mn 0.01(OH) 2, the preparation method comprises the following steps:

[0074] Ni source, Co source and Al source were first prepared into a solution, and then the solution was mixed according to the molar ratio of Ni element in Ni source: Co element in Co source: Al element in Al source of 98:1:2 and passed into the reactor, and then sodium hydroxide and ammonia solution were added to co-precipitate, and finally centrifuged, washed with water and dried to obtain the ternary precursor Ni 0.98 Co 0.01 Mn 0.01 (OH)2.

[0075] At the same time, in the embodiments of this article, in the process of preparing single crystal powder of each ternary material precursor, different calcination temperature and crushing degree parameters will be used based on the differences in doping components and contents. Relevant personnel should know that ternary material precursors with different doping elements and contents need to use specific process conditions when preparing single crystal powder in ternary materials in order to ensure that the doping elements in the single crystal powder can achieve the best doping effect and the best D003 grain size under the said doping degree, and the crystal form of the single crystal powder is the most ideal, which can exert the theoretical best electrochemical performance. Under this condition, relevant personnel can know that the excellent performance of the ternary material described in this article mainly depends on the key physical parameters of the ternary material precursor, and is not determined by irrelevant factors such as the difference in the phase change degree of the single crystal powder during the processing or the difference in the elemental composition of the ternary material precursor itself.

[0076] Example 1-1

[0077] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0078] (1) The ternary material precursor is mixed with LiOH·H2O and ZrO2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrO2: n(Ni+Co+M):n(Li):n(Zr)=1:1.04:0.002, and then calcined at 836°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 57.0±1.0nm. The particles are then crushed twice to a D50 of 3.45μm to obtain single crystal powder; the ternary material precursor is Ni 0.82 Co 0.06 Mn 0.12(OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 82:6:12 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.82 Co 0.06 Mn 0.12 (OH)2; The physical properties of the ternary material precursor are shown in Table 1; wherein B is the specific surface area of ​​the ternary material precursor, X is the I001 / I101 peak intensity ratio of the ternary material precursor, F is the average aspect ratio of the whiskers of the ternary material precursor, as shown in Figure 1, ρ is the true density of the ternary material precursor, δ is the internal porosity of the ternary material precursor, as shown in Figure 2, plasma cutting is first performed, and then software is used for analysis and mapping;

[0079] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 0.8 mol / L and 0.5 mol / L, respectively. H2MoO4 and H2GeO4 were then added at a molar ratio of Mo to Ge of 4:1 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 3 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 150 ° C for 4 h to obtain a modified coated powder.

[0080] (3) H3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0081] Example 1-2

[0082] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 1-1 only in that the physical properties of the ternary material precursor are different. The ternary material precursor is shown in FIG3 , and the physical properties are shown in Table 1. δ is the internal porosity of the ternary material precursor, as shown in FIG4 . Plasma cutting is first performed, and then software is used for analysis and mapping. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 829° C., and the particle size D50 after secondary crushing is 3.38 μm.

[0083] Examples 1-3

[0084] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 1-1 only in that the physical properties of the ternary material precursor are different. The ternary material precursor is shown in FIG5 , and the physical properties are shown in Table 1. δ is the internal porosity of the ternary material precursor, as shown in FIG6 . Plasma cutting is first performed, and then software is used for analysis and mapping. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 825° C., and the particle size D50 after secondary crushing is 3.22 μm.

[0085] Example 2-1

[0086] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0087] (1) The ternary material precursor is mixed with LiOH·H2O and Zr(OH)2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in Zr(OH)2: n(Ni+Co+M):n(Li):n(Zr)=1:1.05:0.001, and then calcined at 804°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 56.0±1.0nm. The particles are then crushed twice to a D50 of 3.15μm to obtain single crystal powder; the ternary material precursor is Ni 0.94 Co 0.04 Mn 0.02 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 94:4:2 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain the ternary precursor Ni 0.94 Co 0.04 Mn 0.02(OH)2; the physical properties of the ternary material precursor are shown in Table 1; the ternary material precursor is shown in Figure 7, and the δ is the internal porosity of the ternary material precursor, as shown in Figure 8, first plasma cutting is performed, and then software is used for analysis and mapping;

[0088] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 1.2 mol / L and 0.8 mol / L, respectively. H2MoO4 and Ge(OH)4 were then added at a molar ratio of Mo to Ge of 7:3 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 0.5 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 160 ° C for 5 h to obtain a modified coated powder.

[0089] (3) Li3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0090] Example 2-2

[0091] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 2-1 only in that the physical properties of the ternary material precursor are different. The ternary material precursor is shown in FIG9 , and the physical properties are shown in Table 1. δ is the internal porosity of the ternary material precursor, as shown in FIG10 . Plasma cutting is first performed, and then software is used for analysis and mapping. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 801°C, and the particle size D50 after secondary crushing is 3.06 μm.

[0092] Example 2-3

[0093] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 2-1 only in that the physical properties of the ternary material precursor are different. The ternary material precursor is shown in FIG11 , and the physical properties are shown in Table 1. δ is the internal porosity of the ternary material precursor, as shown in FIG12 . Plasma cutting is first performed, and then software is used for analysis and mapping. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 798° C., and the particle size D50 after secondary crushing is 2.96 μm.

[0094] Example 3-1

[0095] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0096] (1) The ternary material precursor is mixed with LiOH·H2O and Li2ZrO3 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in Li2ZrO3: n(Ni+Co+M):n(Li):n(Zr)=1:1.045:0.003, and then calcined at 843°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 58.0±1.0nm. The particles are then crushed twice to a D50 of 3.46μm to obtain single crystal powder; the ternary material precursor is Ni 0.88 Co 0.06 Mn 0.06 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 88:6:6 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.88 Co 0.06 Mn 0.06 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0097] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 0.5 mol / L and 0.2 mol / L, respectively. Subsequently, (NH4)2MoO4 and H2GeO4 were added at a molar ratio of Mo to Ge of 1:1 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 5 minutes. Subsequently, centrifugal dehydration was performed in sequence to make the solid content of the slurry 15 wt%, and vacuum dried at 140 ° C for 8 hours to obtain a modified coated powder.

[0098] (3) LiBO2 and the modified coated powder were mixed at a ratio of 1:200, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0099] Example 3-2

[0100] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 3-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 836°C, and the particle size D50 after secondary crushing is 3.52μm.

[0101] Example 3-3

[0102] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 3-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 831°C, and the particle size D50 after secondary crushing is 3.38μm.

[0103] Example 4-1

[0104] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0105] (1) The ternary material precursor is mixed with LiOH·H2O and ZrF4 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrF4: n(Ni+Co+M):n(Li):n(Zr)=1:1.06:0.0012, and then calcined at 802°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 56.5±1.0nm. The particles are then crushed twice to a D50 of 2.88μm to obtain single crystal powder; the ternary material precursor is Ni 0.92 Co 0.05 Mn 0.03 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 92:5:3 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.92 Co 0.05 Mn 0.03(OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0106] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture with concentrations of 1.5 mol / L and 0.6 mol / L, respectively. Mo2O3 and GeO2 were then added at a molar ratio of Mo to Ge of 6:4 to prepare a 0.3 mol / L suspension. Single crystal powder was added under stirring at a mass ratio of solution to single crystal powder of 1:0.6 and mixed for 1 min. The mixture was then centrifuged and dehydrated to obtain a solid content of 8 wt% in the slurry. The mixture was then vacuum dried at 140 °C for 8 h to obtain a modified coated powder.

[0107] (3) B2O3 and the modified coated powder are mixed at a ratio of 1:200, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0108] Example 4-2

[0109] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 4-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 809°C, and the particle size D50 after secondary crushing is 3.12μm.

[0110] Example 4-3

[0111] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 4-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 804°C, and the particle size D50 after secondary crushing is 2.98μm.

[0112] Example 5-1

[0113] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0114] (1) The ternary material precursor is mixed with LiOH·H2O and ZrO2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrO2: n(Ni+Co+M):n(Li):n(Zr)=1:1.06:0.002, and then calcined at 842°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 55.0±1.0nm. The particles are then crushed twice to a D50 of 3.24μm to obtain single crystal powder; the ternary material precursor is Ni 0.82 Co0.06 Mn 0.12 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 82:6:12 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.82 Co 0.06 Mn 0.12 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0115] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture with concentrations of 1.0 mol / L and 0.5 mol / L, respectively. H2MoO4 and H2GeO4 were then added at a molar ratio of Mo to Ge of 4:1 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 3 minutes. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 150°C for 4 hours to obtain a modified coated powder.

[0116] (3) H3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0117] Example 5-2

[0118] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 5-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 838°C, and the particle size D50 after secondary crushing is 3.16μm.

[0119] Example 5-3

[0120] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 5-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 834°C, and the particle size D50 after secondary crushing is 3.32 μm.

[0121] Example 6-1

[0122] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0123] (1) The ternary material precursor is mixed with LiOH·H2O and Zr(OH)4 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in Zr(OH)4: n(Ni+Co+M):n(Li):n(Zr)=1:1.05:0.001, and then calcined at 799°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 54.0±1.0nm. The particles are then crushed twice to a D50 of 3.24μm to obtain single crystal powder; the ternary material precursor is Ni 0.94 Co 0.04 Mn 0.02 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 94:4:2 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25-40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.94 Co 0.04 Mn 0.02 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0124] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 1.2 mol / L and 0.7 mol / L, respectively. H2MoO4 and Ge(OH)4 were then added at a molar ratio of Mo to Ge of 7:3 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 0.5 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 160 ° C for 5 h to obtain a modified coated powder.

[0125] (3) Li3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0126] Example 6-2

[0127] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 6-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 802°C, and the particle size D50 after secondary crushing is 3.15μm.

[0128] Example 6-3

[0129] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 6-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 794°C, and the particle size D50 after secondary crushing is 3.08μm.

[0130] Example 7-1

[0131] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0132] (1) The ternary material precursor is mixed with LiOH·H2O and ZrO2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrO2: n(Ni+Co+M):n(Li):n(Zr)=1:1.045:0.001, and then calcined at 828°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 55.0±1.0nm. The particles are then crushed twice to a D50 of 2.98μm to obtain single crystal powder; the ternary material precursor is Ni 0.90 Co 0.05 Al 0.05(OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Al element in Al source of 90:5:5 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25 to 40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni 0.90 Co 0.05 Al 0.05 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0133] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 1.0 mol / L and 0.4 mol / L, respectively. H2MoO4 and H2GeO4 were then added at a molar ratio of Mo to Ge of 9:1 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 1 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 160 ° C for 5 h to obtain a modified coated powder.

[0134] (3) H3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0135] Example 7-2

[0136] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 6-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 819°C, and the particle size D50 after secondary crushing is 2.86μm.

[0137] Example 7-3

[0138] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 6-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 824°C, and the particle size D50 after secondary crushing is 2.92 μm.

[0139] Example 8-1

[0140] An embodiment of a ternary material precursor and a ternary material prepared therefrom is described herein, and a method for preparing the ternary material comprises the following steps:

[0141] (1) The ternary material precursor is mixed with LiOH·H2O and ZrF4 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrO2: n(Ni+Co+M):n(Li):n(Zr)=1:1.03:0.001, and then calcined at 781°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 55.5±1.0nm. The particles are then crushed twice to a D50 of 2.78μm to obtain single crystal powder; the ternary material precursor is Ni 0.98 Co 0.01 Mn 0.01 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Mn element in Mn source of 98:1:1 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25 to 40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.98 Co 0.01 Mn 0.01 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0142] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture with concentrations of 1.3 mol / L and 0.5 mol / L, respectively. Mo2O3 and GeO2 were then added at a molar ratio of Mo to Ge of 7:3 to prepare a 0.3 mol / L suspension. Single crystal powder was added under stirring at a mass ratio of solution to single crystal powder of 1:0.6 and mixed for 1 min. The mixture was then centrifuged and dehydrated to obtain a solid content of 9 wt% in the slurry. The mixture was then vacuum dried at 140 °C for 5 h to obtain a modified coated powder.

[0143] (3) B2O3 and the modified coated powder are mixed at a ratio of 1:200, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0144] Example 8-2

[0145] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 4-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 775°C, and the particle size D50 after secondary crushing is 2.85μm.

[0146] Example 8-3

[0147] An embodiment of a ternary material precursor and a ternary material prepared therefrom described in this article differs from Example 4-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 768°C, and the particle size D50 after secondary crushing is 2.88μm.

[0148] Comparative Example 1-1

[0149] A ternary material precursor and a ternary material prepared therefrom, wherein the preparation method of the ternary material comprises the following steps:

[0150] (1) The ternary material precursor is mixed with LiOH·H2O and ZrO2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in ZrO2: n(Ni+Co+M):n(Li):n(Zr)=1:1.04:0.002, and then calcined at 843°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 57.0±1.0nm. The particles are then crushed twice to a D50 of 3.41μm to obtain single crystal powder; the ternary material precursor is Ni 0.82 Co 0.06 Mn 0.12(OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Al element in Al source of 82:6:12 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25 to 40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.82 Co 0.06 Mn 0.12 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0151] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 0.8 mol / L and 0.5 mol / L, respectively. H2MoO4 and H2GeO4 were then added at a molar ratio of Mo to Ge of 4:1 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 3 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 150 ° C for 4 h to obtain a modified coated powder.

[0152] (3) H3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0153] Comparative Example 1-2

[0154] A ternary material precursor and a ternary material prepared therefrom, the difference from comparative example 1-1 being that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 824°C, and the particle size D50 after secondary crushing is 3.29 μm.

[0155] Comparative Examples 1-3

[0156] A ternary material precursor and a ternary material prepared therefrom, the difference from comparative example 1-1 being that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 831°C, and the particle size D50 after secondary crushing is 3.31 μm.

[0157] Comparative Example 2-1

[0158] A ternary material precursor and a ternary material prepared therefrom, wherein the preparation method of the ternary material comprises the following steps:

[0159] (1) The ternary material precursor is mixed with LiOH·H2O and Zr(OH)2 according to the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in LiOH·H2O and the molar amount of zirconium atoms in Zr(OH)2: n(Ni+Co+M):n(Li):n(Zr)=1:1.05:0.001, and then calcined at 808°C in an oxygen atmosphere. The obtained particles are crushed by a roller once and passed through a 200-mesh sieve. The D003 grain size of the obtained particles is 56.0±1.0nm. The particles are then crushed twice to a D50 of 3.19μm to obtain single crystal powder; the ternary material precursor is Ni 0.94 Co 0.04 Mn 0.02 (OH)2, the preparation method is to prepare a metal solution with a concentration of 1.8 to 2.0 mol / L according to the molar ratio of Ni element in Ni source: Co element in Co source: Al element in Al source of 94:4:2 and pass it into the reactor, and at the same time, alkali solution (sodium hydroxide solution with a mass concentration of 25 to 40%) and ammonia water (ammonia water solution with a mass concentration of 15 to 25%) are also passed into the reactor, and the flow rate of the metal solution is controlled to be 40 to 60 L / h, the flow rate of ammonia water is 1 to 5 L / h, and the flow rate of alkali solution is 10 to 30 L / h. The reactor maintains a constant temperature of 60 to 80 ° C, maintains a speed of 100 to 200 rpm, and controls the pH in the reactor to be 9 to 11.5 by the flow rate of alkali solution. The materials in the reactor are uniformly mixed under the above conditions, and a precipitation reaction occurs to obtain a precursor slurry. Finally, it is centrifuged, washed with water, and dried to obtain a ternary precursor Ni. 0.94 Co 0.04 Mn 0.02 (OH)2; The physical properties of the ternary material precursor are shown in Table 1;

[0160] (2) LiOH and Li2CO3 were prepared with water to prepare a mixture of 1.2 mol / L and 0.8 mol / L, respectively. H2MoO4 and Ge(OH)4 were then added at a molar ratio of Mo to Ge of 7:3 to prepare a 0.3 mol / L mixed solution. Single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 0.5 min. The mixture was then centrifuged and dehydrated to obtain a slurry with a solid content of 10 wt%, and vacuum dried at 160 ° C for 5 h to obtain a modified coated powder.

[0161] (3) Li3BO3 and the modified coated powder were mixed at a ratio of 1:100, and then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0162] Comparative Example 2-2

[0163] A ternary material precursor and a ternary material prepared therefrom, the difference from comparative example 2-1 being only that the physical properties of the ternary material precursor are different, as shown in Table 1, and the temperature of the oxygen atmosphere calcination in step (1) is 804°C, and the particle size D50 after secondary crushing is 3.12 μm.

[0164] Comparative Examples 2-3

[0165] A ternary material precursor and a ternary material prepared therefrom differ from comparative example 2-1 only in that the physical properties of the ternary material precursor are different, as shown in Table 1. At the same time, the temperature of the oxygen atmosphere calcination in step (1) is 796°C, and the particle size D50 after secondary crushing is 3.05 μm.

[0166] Comparative Example 3-1

[0167] A ternary material precursor and a ternary material prepared therefrom. The preparation method of the ternary material differs from that of Example 2-1 only in that steps (2) and (3) are respectively:

[0168] (2) LiOH and Li2CO3 were prepared into a mixture with concentrations of 1.2 mol / L and 0.8 mol / L, respectively, and single crystal powder was added under stirring at a solution: single crystal powder mass ratio of 1:0.6 and mixed for 0.5 min. Subsequently, the mixture was centrifuged and dehydrated until no obvious liquid was present, and vacuum dried at 160 ° C for 5 h to obtain the modified coated powder;

[0169] (3) Li3BO3 was mixed with the modified coated powder, H2MoO4, and Ge(OH)4 at a molar ratio of Mo to Ge of 7:3, with the addition amount of each substance being the same as that of Example 2-1. The mixture was then calcined at 300°C in an oxygen atmosphere to obtain the ternary material.

[0170] Comparative Example 3-2

[0171] A ternary material precursor and a ternary material prepared therefrom. The preparation method of the ternary material differs from that of Comparative Example 3-1 only in that the single crystal powder used is the same as that of Example 2-2.

[0172] Comparative Example 3-3

[0173] A ternary material precursor and a ternary material prepared therefrom. The preparation method of the ternary material differs from that of Comparative Example 3-1 only in that the single crystal powder used is the same as that of Example 2-3.

[0174] Effect Example 1

[0175] In order to verify the performance of the ternary materials described herein, the ternary materials prepared in each embodiment and comparative example were prepared into lithium-ion battery positive electrode sheets and lithium-ion batteries according to the following method:

[0176] The ternary single crystal positive electrode materials obtained in the above embodiments and comparative examples were mixed with PVDF and conductive carbon black in a mass ratio of 90:5:5 in NMP with a solid content of 40%, and then formed into positive electrode sheets after coating, drying, roller pressing, and punching. The positive electrode sheets were then assembled with metal lithium sheets, separators, and electrolytes in an argon atmosphere glove box to form CR2032 button batteries.

[0177] Then perform the following tests:

[0178] The charge and discharge test at 0.1C, 2.8-4.3V and the cycle performance test at 2.8-4.25V, 1C rate were carried out in a constant temperature box at 25℃.

[0179] The test results are shown in Table 1 and Table 2.

[0180] As can be seen from Tables 1 and 2, the ternary single crystal positive electrode materials prepared in each embodiment of this invention have good discharge specific capacity and capacity retention rate, which is mainly attributed to the ternary material precursor described herein, and the capacity coefficient R of the precursor is also maintained in the range of 0.1 to 1, especially when the capacity coefficient of the ternary precursor, especially when the capacity coefficient is maintained in the range of 0.3 to 0.9, the prepared ternary material has better performance. In contrast, although the chemical composition is the same as that of Examples 1-1 to 1-3 and Examples 2-1 to 2-3, due to the specific surface area, I001 / I101 peak intensity ratio, whisker average aspect ratio, true density and internal porosity of the ternary precursor cannot meet the limited range of this invention, Comparative Examples 1-1 to 1-3 and Comparative Examples 2-1 to 2-3 cannot achieve the expected electrochemical performance. Compared with Examples 2-1 to 2-3, Comparative Examples 3-1 to 3-3 used dry mixing to prepare the ternary material, and the performance of the product was poor.

[0181] Table 1

[0182] Table 2

[0183] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this document and are not intended to limit the scope of protection of this document.

Claims

1. A ternary material precursor, characterized in that: The molecular formula is Ni a Co b M 1-a-b (OH)2, wherein 0.8≤a≤1, 0≤b≤0.1, and M is at least one of Mn, Al, Mg, Ti, Zr, and W; The specific surface area of ​​the ternary material precursor is 5 to 30 m 2 / g, I001 / I101 peak intensity ratio is 0.6-2.5, average whisker aspect ratio is 2-50, true density is 3.4-4.0g / cm 3 , the internal porosity is 1.5~5.0%.

2. The ternary material precursor according to claim 1, characterized in that: The capacity coefficient R of the ternary material precursor satisfies 0.1≤R≤1, and the R capacity coefficient satisfies the following relationship: Wherein B is the specific surface area of ​​the ternary material precursor, X is the I001 / I101 peak intensity ratio of the ternary material precursor, F is the average aspect ratio of the whiskers of the ternary material precursor, ρ is the true density of the ternary material precursor, and δ is the internal porosity of the ternary material precursor.

3. The ternary material precursor according to claim 2, characterized in that: The capacity coefficient R satisfies 0.3≤R≤0.

9.

4. A ternary material, characterized in that: It is prepared from the ternary material precursor according to any one of claims 1 to 3.

5. The ternary material according to claim 4, characterized in that: The ternary material is a single crystal ternary material; the single crystal ternary material is Li x Ni a Co b M c N 1-a-b-c O2, wherein 0.8≤a≤1, 0≤b≤0.1, 0.001≤c≤0.01, M is at least one of Mn, Al, Mg, Ti, Zr, and W, and N is at least one of Zr, Mo, Ge, W, and Al.

6. The method for preparing the ternary material according to claim 4 or 5, characterized in that: The following steps are involved: (1) mixing a ternary material precursor with a lithium source and a doping metal source, and then calcining at 750-850° C. in an oxygen atmosphere, and obtaining single crystal powder after primary crushing, sieving and secondary crushing of the obtained particles; (2) mixing a soluble lithium source and a doping metal source in deionized water, adding the single crystal powder to the resulting mixture under stirring and mixing for 0.5 to 5 minutes, then centrifugally dehydrating and drying in sequence to obtain a modified coated powder; (3) mixing the boron source with the modified coated powder, and then calcining at 280-320° C. in an oxygen atmosphere to obtain the ternary material; The doping metal source is at least one of a zirconium source, a molybdenum source, a chromium source, a tungsten source, and an aluminum source.

7. The method for preparing the ternary material according to claim 6, characterized in that: The lithium source is LiOH, and the doping metal source mixed with the lithium source and the ternary material precursor to prepare the single crystal powder is a zirconium source, and the zirconium source is at least one of ZrO2, Li2ZrO3, Zr(OH)4, and ZrF4; the ratio of the total molar amount of Ni, Co and M in the ternary material precursor, the molar amount of lithium atoms in the lithium source, and the molar amount of zirconium atoms in the zirconium source is: n(Ni+Co+M):n(Li):n(Zr)=1:(1.01~1.06):(0.001~0.01).

8. The method for preparing the ternary material according to claim 6, characterized in that: The D003 grain size of the particles after the first crushing is 50-62 nm.

9. The method for preparing the ternary material according to claim 6, characterized in that: The particle size D of the particles after secondary crushing 50 2.5~4μm.

10. The method for preparing the ternary material according to claim 6, characterized in that: The soluble lithium source is a mixture of LiOH and Li2CO3, the concentration of LiOH in the mixture is 0.5-1.5 mol / L, and the concentration of Li2CO3 is 0.2-0.8 mol / L.

11. The method for preparing a ternary material as claimed in claim 6, wherein the doping metal source mixed with the soluble lithium source is a molybdenum source and a chromium source, the molybdenum source is at least one of Mo2O3, H2MoO4, and (NH4)2MoO4, and the chromium source is at least one of GeO2, H2GeO4, and Ge(OH)4; the molar ratio of the molybdenum atoms in the molybdenum source to the chromium atoms in the chromium source is (1 to 10):

1.

12. The method for preparing the ternary material according to claim 6, characterized in that: The boron source is at least one of B2O3, H3BO3, Li3BO3, LiBO2, CoB, Li2B4O7, and LiB5O8.

13. The method for preparing the ternary material according to claim 6, characterized in that: The mass ratio of the boron source to the modified coated powder is 1:(50-400).

14. A positive electrode plate for a lithium ion battery, characterized in that: Including the ternary material as claimed in claim 4 or 5.

15. A lithium ion battery comprising the lithium ion battery positive electrode sheet according to claim 14.

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