Ternary positive electrode material precursor, preparation method therefor and use thereof

Abstract

A ternary positive electrode material precursor, a preparation method therefor, and a use thereof. In the preparation method, the alkali content of a reaction system is precisely regulated and controlled by balancing the flow rates of a metal salt solution and nitrogen, so as to ensure that needle-shaped primary particles are formed during coprecipitation and to realize the regulation and control of the growth orientation of crystal planes of a crystal, so that the crystal planes grow in a certain orientation. By controlling the flow rate of the metal salt solution on different crystal planes, growth units continuously diffuse to the surface of the crystal, and sites are found on the surface and embedded into crystal lattices, so that a grain size ratio is within a set range. The preparation method precisely regulates and controls the grain size ratio of the grains of the crystal planes of the ternary positive electrode material precursor, and a ternary positive electrode material can inherit the crystal orientation of a precursor, so that the crystal plane orientation of the ternary positive electrode material is better, leading to easier deintercalation of lithium ions, thereby improving the cycle performance of the positive electrode material.

Description

Ternary positive electrode material precursor, preparation method and application thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a ternary positive electrode material precursor, a preparation method and application thereof. BACKGROUND

[0002] Currently, the marketized positive electrode materials mainly include lithium iron phosphate, lithium cobaltate, lithium manganate and ternary positive electrode material (NCM). The ternary positive electrode material is usually prepared by calcining a nickel-cobalt-manganese ternary positive electrode material precursor with a lithium source and / or coating other metal ions, and the precursor can be prepared by a hydroxide co-precipitation method.

[0003] However, the existing ternary positive electrode material precursor has a low specific surface energy on the <001> crystal face, and the precursor is prone to spread along a certain specific crystal face in the co-precipitation reaction. The lithium ion transmission channel is in the active crystal face, and the specific crystal face size is too large, which causes the lithium ion transmission path to be large, and the lithium ion channel is narrow, resulting in weak lithium ion deintercalation capacity of the ternary positive electrode material obtained by sintering, which affects the capacity of the positive electrode material. In order to improve the lithium ion transmission characteristics, a fast ion conductor can be coated, but this can only improve the lithium ion transmission rate on the surface of the positive electrode material, and the internal transmission environment is difficult to improve, and the use of the coating often causes the loss of the energy density of the positive electrode material.

[0004] SUMMARY

[0005] Therefore, the present application provides a preparation method of a ternary positive electrode material precursor, which regulates the crystal structure of the precursor so that the crystal size ratio is within a set range, thereby improving the performance of the ternary positive electrode material.

[0006] In addition, it is necessary to provide a ternary positive electrode material precursor prepared by the above preparation method, a ternary positive electrode material prepared from the ternary positive electrode material precursor, and a lithium ion battery comprising the ternary positive electrode material.

[0007] An embodiment of the present application provides a preparation method of a ternary positive electrode material precursor, comprising the following steps:

[0008] Solution preparation: configure nickel salt, cobalt salt and manganese salt into a metal salt solution, configure a complexing agent solution and a precipitant solution;

[0009] The first-stage co-precipitation reaction: deionized water is added into a reaction container, the reaction container is kept stirring, the complexing agent solution and the precipitant solution are added into the reaction container, the ammonia content in the reaction container is 2 g / L-3 g / L, and the pH value is 11-12; nitrogen gas is introduced into the reaction container, and the metal salt solution, the complexing agent solution and the precipitant solution are introduced into the reaction container at the same time, the pH of the reaction system is 9-13, so that primary particles are generated, and the median particle size D50 of the primary particles is 1.60 μm-2.00 μm; wherein the flow rate of the nitrogen gas is n times the flow rate of the metal salt solution, and 200≤n≤1000;

[0010] The second-stage co-precipitation reaction: the flow rate of the nitrogen gas is increased, the stirring speed of the reaction container is increased, and the flow rate of the metal salt solution is increased, so that the pH of the reaction system is 9-13, so that secondary particles are generated, and the median particle size D50 of the secondary particles is 3.30 μm-5.00 μm; wherein the flow rate of the nitrogen gas after the increase is n times the flow rate of the metal salt solution after the increase, and 200≤n≤1000;

[0011] The post-treatment: the slurry obtained by the second-stage co-precipitation reaction is subjected to centrifugation, washing and drying, so that the ternary positive electrode material precursor is obtained, and the ratio of the grain sizes of the ternary positive electrode material precursor satisfies the following relationship: D(100) / D(001)≤1.98.

[0012] In an implementation manner, the flow rate of the nitrogen gas is 1.5 m 3 / h-10 m 3 / h, and the flow rate of the metal salt solution is 2.5 L / h-10 L / h.

[0013] In an implementation manner, the nickel salt is one or more of a sulfate, a nitrate and a chloride of nickel, the cobalt salt is one or more of a sulfate, a nitrate and a chloride of cobalt, the manganese salt is one or more of a sulfate, a nitrate and a chloride of manganese, and the concentration of the metal salt solution is 2 mol / L-3 mol / L.

[0014] In an implementation manner, the precipitant solution includes a NaOH solution or a KOH solution, and the concentration of the precipitant solution is 5 mol / L-20 mol / L.

[0015] In an implementation manner, the complexing agent solution includes one or more of ammonia water, urea and a soluble ammonium salt, and the concentration of the complexing agent solution is 2 mol / L-10 mol / L.

[0016] In an implementation manner, the reaction temperature in the reaction container is 30℃-70℃.

[0017] One embodiment of this application provides a ternary cathode material precursor, which is prepared by the preparation method described above. The chemical formula of the ternary cathode material precursor is Ni. x Co y Mn z (OH)2, where 0.6≤x<1, 0<y<0.2, 0<z<0.2, x+y+z=1. The grain size ratio of the ternary cathode material precursor satisfies the following relationship: D(100) / D(001)≤1.98.

[0018] One embodiment of this application provides a ternary cathode material, which is prepared from the ternary cathode material precursor described above.

[0019] In one embodiment, the ternary cathode material has the chemical formula LiNi. x Co y Mn z (OH)2, where 0.6≤x<1, 0<y<0.2, 0<z<0.2, x+y+z=1.

[0020] One embodiment of this application provides a lithium-ion battery, including the ternary cathode material as described above.

[0021] The preparation method of this application precisely controls the alkali content of the reaction system by balancing the flow rate (flow rate) of the metal salt solution and nitrogen gas, making the reaction system more stable and controllable. This ensures that the co-precipitation process forms needle-like primary particles, thereby controlling the crystal facet growth orientation and allowing the crystal facets to grow in a specific orientation. On different crystal faces, controlling the flow rate of the metal salt solution allows the growth units to continuously diffuse to the crystal surface and find sites on the surface to combine and embed into the crystal lattice, thus keeping the grain size ratio within a set range. The preparation method of this application can precisely control the grain size ratio of the ternary cathode material precursor. The ternary cathode material can inherit the crystal orientation of the precursor, resulting in a better crystal facet orientation and easier lithium ion insertion / extraction, thereby improving the cycle performance of the cathode material. The preparation method of this application is simple, environmentally friendly, and easy to industrialize. Attached Figure Description

[0022] Figure 1 is a scanning electron microscope (SEM) image of the ternary cathode material precursor of Embodiment 1 of this application.

[0023] Figure 2 is a SEM image of the cross-section of the ternary cathode material precursor of Example 1 of this application after ion polishing (CP).

[0024] Figure 3 is a SEM image of the ternary cathode material precursor of Comparative Example 1 of this application.

[0025] Figure 4 is an SEM image of the section of the ternary positive electrode material precursor of the comparative example 1 of the present application after ion milling CP.

[0026] Figure 5 is an X-ray diffraction (XRD) pattern of the ternary positive electrode material precursor of the example 1 of the present application.

[0027] Figure 6 is an XRD pattern of the ternary positive electrode material precursor of the comparative example 1 of the present application.

[0028] The following detailed description will further illustrate the embodiments of the present application in conjunction with the above-mentioned figures. DETAILED DESCRIPTION

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of the present application belong. The terminology used in the subject specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments belong. The terminology used in the subject specification is for describing particular embodiments only and is not intended to be limiting of the present application. In the event that there is a plurality of definitions for a term herein, those in this section prevail. Where reference is made to a patent or scientific article, a patent application or other publication, a patent, published application, or other publication is referred to by its identify in the reference that it is given and a copy of which is incorporated by reference.

[0030] The first aspect of the present application provides a preparation method of a ternary positive electrode material precursor, comprising steps S1-S4.

[0031] S1, solution preparation: configuring a metal salt solution from nickel salt, cobalt salt and manganese salt, configuring a complexing agent solution and a precipitant solution.

[0032] S2, first-stage co-precipitation reaction: adding deionized water into a reaction vessel, keeping the reaction vessel in a stirring state, adding the complexing agent solution and the precipitant solution into the reaction vessel, so that the ammonia content in the reaction vessel is 2-3 g / L and the pH value is 11-12; introducing nitrogen into the reaction vessel, and simultaneously introducing the metal salt solution, the complexing agent solution and the precipitant solution, so that the pH of the reaction system is 9-13, to generate primary particles, the median particle size D50 of the primary particles being 1.60-3.00 pm; wherein the flow rate of the nitrogen is n times the flow rate of the metal salt solution, 200≤n≤1000.

[0033] S3, second-stage co-precipitation reaction: increasing the flow rate of the nitrogen, increasing the stirring speed of the reaction vessel, and increasing the flow rate of the metal salt solution, so that the pH of the reaction system is 9-13, to generate secondary particles, the median particle size D50 of the secondary particles being 3.30-5.00 pm; wherein the flow rate of the nitrogen after the increase is n times the flow rate of the metal salt solution after the increase, 200≤n≤1000.

[0034] S4, post-processing: the slurry obtained in the second stage co-precipitation reaction is subjected to centrifugation, washing, and drying to obtain the ternary positive electrode material precursor, wherein the grain size ratio of the ternary positive electrode material precursor satisfies the following relationship: D(100) / D(001)≤1.98.

[0035] By balancing the flow rate (flow) of the metal salt solution and nitrogen, the alkali content of the reaction system is accurately controlled, so that the reaction system is more stable and controllable, to ensure that the co-precipitation process forms needle-like primary particles, realizes the control of the crystal face growth orientation, and makes the crystal face grow in a certain orientation. On different crystal faces, the flow rate of the metal salt solution is controlled to make the growth units continuously diffuse to the crystal surface and find a point to combine and embed into the crystal lattice, so that the grain size ratio is within the set range. The preparation method of the present application can accurately control the grain size ratio of the crystal face of the ternary positive electrode material precursor, the ternary positive electrode material can inherit the crystal direction of the precursor, the crystal face orientation in the layered structure of the ternary positive electrode material is more optimal, the lithium deintercalation channel is increased, the ionic conductivity is reduced, and the lithium ion is more easily deintercalated, so that the cycle performance of the positive electrode material can be improved.

[0036] In some embodiments, the nickel salt is one or more of a sulfate, a nitrate, and a chloride of nickel, the cobalt salt is one or more of a sulfate, a nitrate, and a chloride of cobalt, and the manganese salt is one or more of a sulfate, a nitrate, and a chloride of manganese. For example, the nickel salt can be, but is not limited to, nickel sulfate (NiSO4·6H2O), the cobalt salt can be, but is not limited to, cobalt sulfate (CoSO4·7H2O), and the manganese salt can be, but is not limited to, manganese sulfate (MnSO4·H2O).

[0037] In some embodiments, the concentration of the metal salt solution is 2 mol / L to 3 mol / L. For example, the concentration of the metal salt solution can be 2 mol / L, 2.1 mol / L, 2.2 mol / L, 2.3 mol / L, 2.4 mol / L, 2.5 mol / L, 2.6 mol / L, 2.7 mol / L, 2.8 mol / L, 2.9 mol / L, 3 mol / L, or any value between any two adjacent values in the foregoing. In the metal salt solution, the molar ratio of nickel, cobalt, and manganese can be 0.95:0.03:0.02.

[0038] Further, the concentration of the metal salt solution can be 2 mol / L to 2.5 mol / L.

[0039] In some embodiments, the precipitant solution comprises a NaOH solution or a KOH solution, and the concentration of the precipitant solution is 5 mol / L to 20 mol / L. For example, the concentration of the precipitant solution can be 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, 10 mol / L, 11 mol / L, 15 mol / L, 16 mol / L, 18 mol / L, 20 mol / L, or any value between any two adjacent values in the above range.

[0040] Further, the concentration of the precipitant solution can be 6 mol / L to 9 mol / L.

[0041] In some embodiments, the complexing agent solution comprises one or more of ammonia (NH3·H2O), urea, and soluble ammonium salt, and the concentration of the complexing agent solution is 2 mol / L to 10 mol / L. For example, the concentration of the complexing agent solution can be 2 mol / L, 3 mol / L, 4 mol / L, 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, 10 mol / L, or any value between any two adjacent values in the above range.

[0042] Further, the concentration of the complexing agent solution can be 4 mol / L to 8 mol / L.

[0043] In some embodiments, the reaction temperature in the reaction container is 30°C to 70°C.

[0044] Further, the reaction temperature can be 40°C to 55°C.

[0045] In some embodiments, the ammonia concentration in the reaction system in steps S2 and S4 is 0.05 mol / L to 0.9 mol / L.

[0046] Further, the ammonia concentration in the reaction system can be 0.2 mol / L to 0.5 mol / L.

[0047] In some embodiments, the reaction container can be, but is not limited to, a reaction kettle.

[0048] The second aspect of the present application provides a ternary positive electrode material precursor prepared by the above preparation method, which has a chemical formula of Ni x Co y Mn z (OH)2, wherein 0.6≤x<1, 0

[0049] The third aspect of the present application provides a ternary positive electrode material, which can be obtained by mixing and sintering the ternary positive electrode material precursor and a lithium source. x Co y Mn z (OH)2, wherein 0.6≤x<1, 0

[0050] The fourth aspect of the present application provides a lithium ion battery, which comprises a positive electrode sheet, a negative electrode sheet and a separator. The positive electrode sheet comprises a positive electrode current collector and a positive electrode active material layer arranged on the surface of the positive electrode current collector, and the positive electrode active material layer comprises the ternary positive electrode material as described above.

[0051] The embodiments of the present application will be described in detail below in combination with specific examples and comparative examples.

[0052] Example 1

[0053] S1, NiSO4·6H2O, CoSO4·7H2O and MnSO4·H2O were weighed according to the molar ratio of Ni:Co:Mn=0.95:0.03:0.02, dissolved in deionized water to prepare a 2.2 mol / L metal salt aqueous solution. A 7.8 mol / L NaOH (sodium hydroxide) aqueous solution was prepared as a precipitant, and a 6.5 mol / L NH3·H2O (ammonia) was prepared as a complexing agent.

[0054] S2, deionized water was added to the 100 L reactor until it was flush with the flow hood, the temperature of the reactor was controlled at 40°C, the stirring speed was set to 34 Hz, then ammonia and sodium hydroxide solutions were added to adjust the bottom liquid, so that the ammonia content in the reactor was 2.5 g / L, and the pH value was adjusted to 11.75. Nitrogen gas (99.99 vol%) was introduced into the reactor, and the gas flow rate was 1.5 m 3 / h. The above prepared metal salt aqueous solution, sodium hydroxide aqueous solution and ammonia were simultaneously added to the reactor by a metering pump, the addition amount of the metal salt aqueous solution was set to 2.5 L / h (the flow rate of nitrogen gas was n times the flow rate of the metal salt solution, n=600), and the addition amount of the sodium hydroxide solution and the ammonia was automatically adjusted according to the pH value and the ammonia concentration to ensure that the ammonia content gradually increased to 4 g / L and the pH value gradually decreased to 11.60, and the first-stage co-precipitation reaction was carried out until the median particle size D50 of the obtained product was 1.60 μm. During the reaction, the remaining clear liquid was discharged through a concentrator.

[0055] S3, the flow rate of nitrogen gas was adjusted to 3.0 m 3 / h, the stirring speed was increased to 36 Hz, the flow rate of the metal salt aqueous solution was adjusted to 5 L / h (n = 600), the ammonia content was kept at 4 g / L, the pH value was gradually decreased to 11.20, and the second-stage co-precipitation reaction was performed until the median particle size D50 of the obtained product was 3.30 μm.

[0056] S4, the slurry obtained in step S3 was aged (aging temperature 40℃, aging time 2h), after aging, the slurry was washed with an alkaline solution at 40℃ and pure water alternately, and then the filter cake was dried in a hot air circulation oven at 130℃ for 12h to obtain a ternary positive electrode material precursor in powder form.

[0057] The SEM images of the ternary positive electrode material precursor prepared in Example 1 are shown in Figures 1 and 2. As can be seen from Figures 1 and 2, the precursor is a secondary particle formed by agglomeration of primary particles, which includes a uniform dense inner core and a uniform dense outer layer wrapping the inner core. The dense inner core has a dense structure formed by stacked unit cells, and the dense outer layer has a tiled structure formed by stacked strip-shaped primary particles.

[0058] Example 2

[0059] Example 2 differs from Example 1 in that in step S2, the flow rate of nitrogen is 2 m 3 / h, n = 800; in step S3, the flow rate of nitrogen is 4 m 3 / h, n = 800. The rest are the same as Example 1, which will not be repeated here.

[0060] Comparative Example 1

[0061] Comparative Example 1 differs from Example 1 in that in step S2, the flow rate of nitrogen is 5 m 3 / h, n = 2000; in step S3, the flow rate of nitrogen is 10 m 3 / h, n = 2000. The rest are the same as Example 1, which will not be repeated here.

[0062] The SEM images of the ternary positive electrode material precursor prepared in Comparative Example 1 are shown in Figures 3 and 4. As can be seen from Figures 3 and 4, the ternary precursor material is a secondary particle formed by agglomeration of primary particles, which includes a loose inner core and three dense outer layers formed on the surface of the loose inner core. The loose inner core has a honeycomb-like structure formed by interlaced fiber sheet-shaped primary particles, and the dense outer layer has a radial structure formed by strip-shaped primary particles.

[0063] Comparative Example 2

[0064] Comparative Example 2 differs from Example 1 in that in step S2, the flow rate of nitrogen is 0.2 m 3 / h, n = 80. In step S3, the flow rate of nitrogen was 0.4 m 3 / h, n = 80. The rest are the same as Example 1, which will not be repeated here.

[0065] The reaction parameters of each of the above examples and comparative examples are shown in Table 1.

[0066] Table 1

[0067] The ternary positive electrode material precursors of Examples 1-2 and Comparative Examples 1-2 were respectively subjected to XRD testing, and the XRD patterns of Example 1 and Comparative Example 1 are shown in Figures 5 and 6. According to the XRD patterns, and in combination with the Scherrer formula: (wherein K is 0.89 when β is the half-height width, λ is the X-ray wavelength, and θ is the diffraction angle), the crystal size D of each crystal face can be calculated, and thus the D(100) / D(001) grain size ratio is obtained. The XRD testing equipment is Bruker D8 advance, the scanning code range is 10-80°, the step size is 0.02, and the dwell time is 0.3s.

[0068] According to the XRD patterns, and using JADE software, the I(101) / I(001) crystal face peak area ratio of the ternary positive electrode material precursors of Examples 1-2 and Comparative Examples 1-2 was obtained.

[0069] The median particle size D50 of the ternary positive electrode material precursors of Examples 1-2 and Comparative Examples 1-2 was respectively tested using a D50 testing equipment: Mastersizer 3000.

[0070] The specific surface area of the ternary positive electrode material precursors of Examples 1-2 and Comparative Examples 1-2 was respectively tested using a specific surface area testing equipment: 3H-2000A.

[0071] The above test results are shown in Table 2.

[0072] Table 2

[0073] The ternary positive electrode material precursors of Examples 1-2 and Comparative Examples 1-2 were sintered with LiOH respectively to prepare ternary positive electrode materials. Then the ternary positive electrode materials of each of the above examples and comparative examples were mixed with the conductive active material SuperP and the binder PVDF in a ratio of 90:5:5 to form a slurry, which was then uniformly coated on an aluminum foil to prepare a positive electrode sheet. The negative electrode was a high-purity lithium sheet, the separator was a Celgard 2400 type polypropylene separator, and the electrolyte was a 1 mol / L LiPF6 solution in a mixed solvent of EC and DMC (volume ratio 1:1). A CR2032 type button cell was assembled in a vacuum glove box, and then electrochemical tests were performed. The specific test steps are as follows, and the test results are shown in Table 3.

[0074] Electrochemical tests were performed using a button cell, with a voltage platform of 4.30 V, 2 cycles of capacity distribution, and 51 cycles of circulation. The LANDdt V7 software was used for data acquisition to obtain the charge and discharge capacity, the initial efficiency (constant capacity discharge gram capacity / total charge gram capacity), and the DCR data.

[0075] Table 3

[0076] As shown in Table 3, the total charge gram capacity, constant capacity discharge gram capacity, initial efficiency, and second cycle discharge gram capacity of the battery prepared by the precursors of Examples 1-2 were all higher than those of the batteries of Comparative Examples 1-2, and the charge DCR and discharge DCR were all lower than those of the batteries of Comparative Examples 1-2. Therefore, the precursors of Examples 1-2 can improve the electrochemical performance of the battery, making the battery have higher capacity and better cycle performance.

[0077] The preparation method of the present application precisely controls the alkali content of the reaction system by balancing the flow rate (flow) of the metal salt solution and nitrogen, making the reaction system more stable and controllable, to ensure that the co-precipitation process forms needle-shaped primary particles, realizes the regulation of crystal face growth orientation, and makes the crystal face grow in a certain orientation. On different crystal faces, the flow rate of the metal salt solution is controlled to make the growth units continuously diffuse to the crystal surface and find a point to combine and embed in the crystal lattice, so that the crystal size ratio is within a certain range. The preparation method of the present application can precisely regulate the crystal face and grain size ratio of the ternary positive electrode material precursor, the ternary positive electrode material can inherit the crystal orientation of the precursor, the crystal face orientation of the ternary positive electrode material is more optimal, and lithium ions are more easily deintercalated, thereby improving the cycle performance of the positive electrode material. The preparation method of the present application is simple, environmentally friendly, and easy to industrialize.

[0078] The above description is some specific embodiments of the present application, but in actual application, it cannot be limited to these embodiments. Other modifications and changes made by those skilled in the art according to the technical concept of the present application should also fall within the protection scope of the present application.

Claims

1. A preparation method of a ternary cathode material precursor, characterized in that, The preparation method comprises the following steps: Solution preparation: configuring nickel salt, cobalt salt and manganese salt into a metal salt solution, configuring a complexing agent solution and a precipitant solution; First-stage co-precipitation reaction: adding deionized water into a reaction container, keeping the reaction container in a stirring state, adding the complexing agent solution and the precipitant solution into the reaction container, so that the ammonia content in the reaction container is 2 g / L-3 g / L and the pH value is 11-12; introducing nitrogen into the reaction container, and simultaneously introducing the metal salt solution, the complexing agent solution and the precipitant solution, so that the pH of the reaction system is 9-13, to generate primary particles, the median particle size D50 of the primary particles being 1.60 μm-2.00 μm; wherein the flow rate of the nitrogen is n times the flow rate of the metal salt solution, 200≤n≤1000; Second-stage co-precipitation reaction: increasing the flow rate of the nitrogen, increasing the stirring speed of the reaction container, and increasing the flow rate of the metal salt solution, so that the pH of the reaction system is 9-13, to generate secondary particles, the median particle size D50 of the secondary particles being 3.30 μm-5.00 μm; wherein the flow rate of the nitrogen after the increase is n times the flow rate of the metal salt solution after the increase, 200≤n≤1000; Post-treatment: centrifuging, washing and drying the slurry obtained in the second-stage co-precipitation reaction, to obtain the ternary positive electrode material precursor, the grain size ratio of the ternary positive electrode material precursor satisfying the following relationship: D(100) / D(001)≤1.

98.

2. The production method according to claim 1, wherein The flow rate of the nitrogen gas is 1.5 m 3 / h ~ 10 m 3 / h, and the flow rate of the metal salt solution is 2.5 L / h ~ 10 L / h.

3. The production method according to claim 1, wherein The nickel salt is one or more of a sulfate salt, a nitrate salt and a chloride salt of nickel; the cobalt salt is one or more of a sulfate salt, a nitrate salt and a chloride salt of cobalt; the manganese salt is one or more of a sulfate salt, a nitrate salt and a chloride salt of manganese; and the concentration of the metal salt solution is 2 mol / L-3 mol / L.

4. The production method according to claim 1, wherein The precipitant solution comprises a NaOH solution or a KOH solution, and the concentration of the precipitant solution is 5 mol / L-20 mol / L.

5. The production method according to claim 1, wherein The complexing agent solution comprises one or more of ammonia, urea and a soluble ammonium salt, and the concentration of the complexing agent solution is 2 mol / L-10 mol / L.

6. The production method according to claim 1, wherein The reaction temperature in the reaction container is 30°C-70°C.

7. A ternary cathode material precursor, characterized in that, The ternary cathode material precursor is prepared by the preparation method in any one of claims 1 to 6, and a chemical formula of the ternary cathode material precursor is Ni x Co y Mn z (OH)2, wherein 0.6≤x<1, 0 The grain size ratio of the ternary cathode material precursor satisfies the following relationship: D(100) / D(001)≤1.

98.

8. A ternary positive electrode material, characterized by, The ternary positive electrode material is prepared from the ternary positive electrode material precursor according to claim 7.

9. The ternary cathode material of claim 8, wherein, The ternary positive electrode material has a chemical formula of LiNi x Co y Mn z (OH)2, wherein 0.6≤x<1, 0 10. A lithium-ion battery, characterized by, The ternary positive electrode material comprises the ternary positive electrode material according to claim 8 or 9.

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