A method for preparing ultra-high nickel positive electrode material

Abstract

The present invention belongs to the technical field of lithium-ion batteries, and specifically relates to a method for preparing an ultra-high nickel positive electrode material, comprising the following steps: S1: mixing a ternary precursor with a cerium source and a lithium source, and obtaining Ce-NCM by a high-temperature solid-phase method; S2: ball-milling a lanthanum source, a zirconium source and other metal sources, and heat-treating the mixture to obtain a doped La2Zr 2‑x M x O7, ball milling was performed to obtain nano-scale La2Zr 2‑x M x O7 ion conductor powder; S3: Ce-NCM and organic coating medium solution are mixed and stirred evenly, added into the second solvent for mixed precipitation, filtered, washed and dried to obtain the positive electrode material Ce-PNCM; S4: Nano-scale La2Zr prepared in S2 is added to the 2‑x M x O7 ion conductor powder and the positive electrode material Ce-PNCM are mixed in a high-speed mixer and subjected to a secondary heat treatment under protective gas conditions to produce a cerium-doped double-coated ultra-high nickel positive electrode material. The positive electrode material prepared by this method has low residual soluble lithium on the surface, high surface coating uniformity, good electrochemical stability, excellent cycling performance, and high charge-discharge capacity.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium-ion batteries, and in particular relates to a method for preparing an ultra-high nickel positive electrode material. Background Art

[0002] Ultra-high nickel ternary positive electrode material LiNi x Co y Mn z O(x+y+z=1,x≥0.9) has good development prospects due to its high specific capacity and high discharge platform. At the same time, the ultra-high nickel content ternary positive electrode material has the following problems: (1) The preparation process conditions are difficult to control, which can easily lead to a high amount of residual lithium on the surface of the sintered product, which reacts with oxygen and CO2 in the air to generate LiOH and Li2CO3, resulting in a high amount of residual lithium on the surface; (2) The cycle performance is poor. As the Ni content increases, it is easy to cause Mn to escape during the charge and discharge cycle. After multiple cycles, Mn 3+ The disproportionation reaction causes a change in valence, leading to the collapse of the cathode material's layered structure and the intensification of cracks in the cathode material, ultimately reducing the material's cycling performance. Therefore, improving these issues is the primary goal in developing ultra-high nickel ternary cathode materials.

[0003] Doping can improve the structural stability of ultra-high nickel positive electrode materials, and auxiliary surface coating can reduce the generation of residual alkali and side reactions, thereby improving the structural stability and cycle performance of the positive electrode materials. In addition, lanthanum zirconate can be combined with the positive electrode material for heat treatment to react the residual LiOH on the surface with Li2CO3 to generate lithium lanthanum zirconium oxide (LLZO), thereby improving the electrical conductivity and thus improving the capacity and rate performance of the positive electrode material. The invention patent with announcement number CN114695852A provides a method for preparing a carbon-coated positive electrode material, which improves the surface conductivity and rate performance of the positive electrode material, but carbon coating will cause a decrease in the specific capacity of the material. The invention patent with announcement number CN114628663A provides a method for preparing a cerium-doped modified positive electrode material, which prepares a porous structure positive electrode material by doping cerium, improves the high-temperature storage capacity retention rate and cycle performance, and fails to solve the problems of high residual alkali content and poor air stability of the ultra-high nickel ternary positive electrode material system. Therefore, it is very necessary to research and develop a preparation method to reduce the surface soluble lithium residue of ultra-high nickel positive electrode materials and obtain ultra-high nickel positive electrode materials with high surface coating uniformity, good electrochemical stability, good cycle performance, and high charge and discharge capacity.

[0004] The method of the present invention improves the structure and electrical conductivity of the high-nickel material. The structural stability of the material is improved by doping cerium. Lanthanum zirconate combines with the residual alkali on the surface of the material to form a coating layer that utilizes the residual alkali on the surface of the material. The superimposed carbon coating layer improves the electrical conductivity of the material, inhibits the influence of H2O and CO2 in the air on the material, and improves the air storage performance of the material. Summary of the Invention

[0005] The present invention aims to solve the above technical problems and provide a method for preparing an ultra-high nickel positive electrode material, which can prepare an ultra-high nickel positive electrode material with low surface soluble lithium residue, high surface coating uniformity, good electrochemical stability, good cycle performance, and high charge and discharge capacity.

[0006] The technical solution of the present invention is:

[0007] A method for preparing an ultra-high nickel positive electrode material comprises the following steps:

[0008] (1): The ternary precursor is mixed with a cerium source and a lithium source, and a cerium-doped ternary cathode material Ce-NCM is obtained by a high-temperature solid-phase method;

[0009] (2): The lanthanum source, zirconium source and other metal sources are ball-milled and mixed, and then heat-treated to obtain doped La2Zr 2-x M x O7, continue ball milling to obtain nano-scale La2Zr 2-x M x O7 ion conductor powder;

[0010] (3): The cerium-doped ternary cathode material Ce-NCM is mixed and stirred evenly with the organic coating medium solution, and the stirred mixture is added into a second solvent for mixed precipitation, and filtered, washed, and dried to obtain a dry surface-coated cathode material Ce-PNCM;

[0011] (4): The nano-scale La2Zr prepared in step (2) 2-x M x The O7 ion conductor powder is mixed with the dried surface-coated positive electrode material Ce-PNCM, and a secondary heat treatment is performed under protective gas conditions to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

[0012] Preferably, in step (1) of the present invention, the ternary precursor is Ni x Co y Mn z (OH)2, where x+y+z=1, x≥0.9.

[0013] Cerium doping can increase the interlayer spacing in the positive electrode material, expand the diffusion channel of lithium ions, and facilitate ion transport. Cerium doping also reduces the generation of oxygen vacancies, which is beneficial for the growth of the material's crystal structure towards an ordered phase, thereby improving the structural stability of the material and making the cycle performance during charge and discharge more stable.

[0014] Preferably, in step (1) of the present invention, the molar ratio of the ternary precursor to the lithium source is 1:1.025-1.1, and the amount of the cerium source added is 0.1wt%-2wt% of the ternary precursor. When the amount of the cerium source added exceeds 2wt%, CeO2 impurities will be generated, causing the accumulation of an inert layer of the material, destroying the stability of the material unit cell structure, reducing the lithium ion diffusion efficiency, and ultimately causing a decrease in the cycle performance and rate performance of the sample.

[0015] Preferably, in step (1) of the present invention, the cerium source is one of cerium oxide, cerium hydroxide, and cerium acetate hexahydrate, and the lithium source is LiOH or Li2CO3.

[0016] Preferably, in step (1) of the present invention, the high-temperature solid-phase method is a two-stage sintering: the first stage sintering temperature is 420-600°C, preferably 450-500°C, and the time is 1-3h; the second stage sintering temperature is 710-820°C, preferably 730-760°C, and the time is 8-20h.

[0017] Preferably, in step (2) of the present invention, the lanthanum source is lanthanum oxide or lanthanum hydroxide, the zirconium source is one of zirconium oxide, zirconium hydroxide, and zirconium carbonate, and the metal source is one or more of Y2O3, Sc2O3, Er2O3, Gd2O3, Yb2O3, Nb2O3, WO3, MgO, and TiO2.

[0018] Preferably, in step (2) of the present invention, the molar ratio of the lanthanum source to the zirconium source is 1:1, and the amount of other metal sources added is 0-2wt% of the total amount of the lanthanum source and the zirconium source. 2-x M x O7 ion conductor powder provides holes for free protons or electrons, improving the conductivity of the material. It can subsequently be used as a coating material to improve the conductivity of the coated core material (positive electrode material).

[0019] Preferably, in step (2) of the present invention, the ball milling mixing time is 2-4 hours, the heat treatment temperature is 1200-1400° C., and the time is 5-8 hours. After the heat treatment, the ball milling is continued until the particle size is 50-200 nm.

[0020] Preferably, in step (3) of the present invention, the organic coating medium solution is a water-soluble carbon-based organic matter with a concentration of 1 wt% to 15 wt%, and the water-soluble carbon-based organic matter is one or more of PVA, PAN, CMC, and PAM.

[0021] Preferably, in step (3) of the present invention, the mass ratio of the organic coating medium solution and the cerium-doped ternary positive electrode material Ce-NCM is 1:0.01-0.1, and the mixing and stirring conditions are: stirring temperature of 5-15°C, stirring speed of 200-700r / min, and stirring time of 5-15min.

[0022] Preferably, in step (3) of the present invention, the volume ratio of the mixed liquid to the second solvent is 1:0.3-1.5, and the second solvent is ethanol or propanol.

[0023] Preferably, in step (4) of the present invention, after mixing for 0.5-3 hours, the mixture is subjected to a secondary heat treatment at 800-950°C for 1-5 hours in an argon or nitrogen protective gas. If the heat treatment time is too long, the stress of the internal grain growth of the positive electrode material will be too large, destroying the internal structure and affecting its performance. In the double coating layer after the secondary heat treatment, the inner coating layer is a carbon coating layer, and the outer coating layer is a nano-scale La2Zr 2-x M x O7 ion conductor layer. The combination of carbon coating layer and ion conductor layer can improve the interface compatibility between materials, reduce interface impedance and promote the migration of lithium ions. Carbon-based organic matter is used to evenly coat the surface of the material. After secondary heat treatment, no other impurities that affect the performance of the material will be generated. The polymer in the organic coating layer absorbs the metal ions of the material through hydrogen bonds, coordination bonds and surface functional groups to achieve a uniform coating effect. The carbon coating layer does not affect the Li ion on the surface of the material during the charge and discharge cycle. + The diffusion of the positive electrode material can improve the conductivity and rate performance of the material without changing the lattice framework of the positive electrode material.

[0024] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. The method of the present invention can be used to prepare an ultra-high nickel positive electrode material with low surface soluble lithium residue, high surface coating uniformity, good electrochemical stability, good cycle performance, and high charge and discharge capacity.

[0026] 2. In the method of the present invention, the inner layer of the ternary cathode material Ce-NCM is first coated with a carbon coating layer, and the outer coating layer is a nano-scale La2Zr 2-x M x The combination of the O7 ion conductor layer and the carbon coating layer can improve the interface compatibility between materials, reduce the interface impedance, promote the migration of lithium ions, and improve the conductivity and rate performance of the material without changing the lattice framework of the positive electrode material. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the SEM image of the ultra-high nickel positive electrode material in Example 2 of the present invention.

[0028] Figure 2 This is the XRD diffraction peak diagram of the positive electrode material generated under the conditions of Example 2 and Comparative Example 1.

[0029] Figure 3 This is a flow chart of the preparation method of the ultra-high nickel positive electrode material of the present invention. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0031] Example 1

[0032] (1) The ternary precursor Ni 0.9 Co 0.03 Mn 0.07 (OH)2 is mixed with cerium oxide and lithium hydroxide and sintered in two stages. The first stage is sintered at 600℃ for 1h; the second stage is sintered at 750℃ for 15h to obtain cerium-doped ternary positive electrode material Ce-NCM. The Ni 0.9 Co 0.03 Mn 0.07 The molar ratio of (OH)2 to lithium hydroxide is 1:1.045, and the amount of cerium oxide added is Ni 0.9 Co 0.03 Mn 0.07 0.1 wt% of (OH)2;

[0033] (2) lanthanum oxide and zirconium oxide were ball-milled for 3 h at a molar ratio of 1:1, and then heat-treated at 1200 °C for 5 h to obtain doped La2Zr2O7. The ball milling was continued to obtain nano-scale La2Zr2O7 ion conductor powder (LZO) with a particle size of 50-200 nm.

[0034] (3) The cerium-doped ternary positive electrode material Ce-NCM was mixed with a 3 wt% PVA solution in a mass ratio of 1:0.03 and stirred evenly. The stirring temperature was 10°C, the stirring speed was 300 r / min, and the stirring time was 15 min. The stirred mixture was mixed with ethanol in a volume ratio of 1:0.5 and precipitated for 2 h. After filtering and washing, it was dried at 120°C for 5 h to obtain a dry surface-coated positive electrode material Ce-PNCM.

[0035] (4) The nano-scale La2Zr prepared in step (2) 2-x M xThe O7 ion conductor powder and the surface-coated positive electrode material were mixed in a high-speed mixer for 1 hour, and then subjected to a secondary heat treatment at 900°C for 3 hours under argon conditions. After natural cooling, the powder was sieved to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

[0036] Example 2

[0037] (1) The ternary precursor Ni 0.94 Co 0.03 Mn 0.03 (OH)2 is mixed with cerium oxide and lithium hydroxide and sintered in two stages. The first stage is sintered at a temperature of 420°C for 3 hours and the second stage is sintered at a temperature of 750°C for 10 hours to obtain a cerium-doped ternary positive electrode material Ce-NCM. The Ni 0.9 Co 0.03 Mn 0.07 The molar ratio of (OH)2 to lithium hydroxide is 1:1.025, and the amount of cerium oxide added is Ni 0.9 Co 0.03 Mn 0.07 1 wt% of (OH)2;

[0038] (2) Lanthanum oxide and zirconium oxide were mixed in a molar ratio of 1:1, and then Sc2O3 and Y2O3 (the mass ratio of the two was 1:1) with a total mass of 1 wt% of lanthanum oxide and zirconium oxide were added, and the mixture was ball-milled for 3 h, and then heat-treated at 1200 ° C for 8 h to obtain La2Zr doped 2-x M x O7, continue ball milling to obtain nano-scale La2Zr with a particle size of 50-200nm 2-x M x O7 ion conductor powder (LZMO);

[0039] (3) The cerium-doped ternary positive electrode material Ce-NCM was mixed with a 10 wt% PVA solution in a mass ratio of 1:0.01 and stirred evenly. The stirring temperature was 10°C, the stirring speed was 300 r / min, and the stirring time was 15 min. The stirred mixture was mixed with ethanol in a volume ratio of 1:0.3 and precipitated for 2 h. After filtering and washing, it was dried at 120°C for 5 h to obtain a dry surface-coated positive electrode material Ce-PNCM.

[0040] (4) The nano-scale La2Zr prepared in step (2) 2-x M x The O7 ion conductor powder and the surface-coated positive electrode material were mixed in a high-speed mixer for 3 hours, and then subjected to a secondary heat treatment at 950°C for 3 hours under argon conditions. After natural cooling, the powder was sieved to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

[0041] Example 3

[0042] (1) The ternary precursor Ni 0.9 Co 0.03 Mn 0.07 (OH)2 is mixed with cerium hydroxide and lithium hydroxide and sintered in two stages. The first stage is sintered at a temperature of 500°C for 2 hours and the second stage is sintered at a temperature of 820°C for 8 hours to obtain a cerium-doped ternary positive electrode material Ce-NCM. The Ni 0.9 Co 0.03 Mn 0.07 The molar ratio of (OH)2 to lithium hydroxide is 1:1.035, and the amount of cerium hydroxide added is Ni 0.9 Co 0.03 Mn 0.07 2 wt% of (OH)2;

[0043] (2) Lanthanum hydroxide and zirconium carbonate were mixed in a molar ratio of 1:1, and then MgO, Yb2O3, and WO3 (the mass ratio of the three was 1:1:1) with a total mass of 0.6 wt% of lanthanum hydroxide and zirconium carbonate were added, and the mixture was ball-milled for 3 h, and then heat-treated at 1200 ° C for 8 h to obtain La2Zr doped 2-x M x O7, continue ball milling to obtain nano-scale La2Zr with a particle size of 50-200nm 2-x M x O7 ion conductor powder (LZMO);

[0044] (3) The cerium-doped ternary cathode material Ce-NCM was mixed with a 1 wt% PVA solution at a mass ratio of 1:0.08 and stirred evenly. The stirring temperature was 10°C, the stirring speed was 300 r / min, and the stirring time was 15 min. The stirred mixture was mixed with propanol at a volume ratio of 1:0.5 for precipitation for 2 h. After filtering and washing, it was dried at 120°C for 5 h to obtain a dry surface-coated cathode material Ce-PNCM.

[0045] (4) The nano-scale La2Zr prepared in step (2) 2-x M x The O7 ion conductor powder and the surface-coated positive electrode material were mixed in a high-speed mixer for 3 hours, and then subjected to a secondary heat treatment at 950°C for 3 hours under argon conditions. After natural cooling, the powder was sieved to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

[0046] Example 4

[0047] (1) The ternary precursor Ni 0.94 Co 0.03 Mn 0.03(OH)2 was mixed with cerium acetate hexahydrate and lithium carbonate and sintered in two stages. The first stage was sintered at 450°C for 3 hours and the second stage was sintered at 710°C for 20 hours to obtain a cerium-doped ternary positive electrode material Ce-NCM. The Ni 0.9 Co 0.03 Mn 0.07 The molar ratio of (OH)2 to lithium carbonate is 1:1.1, and the amount of cerium acetate hexahydrate added is Ni 0.9 Co 0.03 Mn 0.07 0.1 wt% of (OH)2;

[0048] (2) Lanthanum oxide and zirconium hydroxide were mixed in a molar ratio of 1:1, and then Er2O3, Gd2O3, Nb2O3, and TiO2 (the mass ratio of the four was 1:1:1:1) with a total mass of 2 wt% of the lanthanum oxide and zirconium hydroxide were added respectively, and the mixture was ball-milled for 3 h, and then heat-treated at 1200 ° C for 8 h to obtain La2Zr doped 2-x M x O7, continue ball milling to obtain nano-scale La2Zr with a particle size of 50-200nm 2-x M x O7 ion conductor powder (LZMO);

[0049] (3) The cerium-doped ternary cathode material Ce-NCM was mixed with a 15 wt% PVA solution in a mass ratio of 1:0.1 and stirred evenly. The stirring temperature was 10°C, the stirring speed was 300 r / min, and the stirring time was 15 min. The stirred mixture was mixed with ethanol in a volume ratio of 1:1.5 and precipitated for 2 h. After filtering and washing, it was dried at 120°C for 5 h to obtain a dry surface-coated cathode material Ce-PNCM.

[0050] (4) The nano-scale La2Zr prepared in step (2) 2-x M x The O7 ion conductor powder and the surface-coated positive electrode material were mixed in a high-speed mixer for 3 hours, and then subjected to a secondary heat treatment at 950°C for 3 hours under argon conditions. After natural cooling, the powder was sieved to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

[0051] Comparative Example 1

[0052] The difference from Example 3 is that steps (2) to (4) are not included, and the rest are the same as Example 3.

[0053] Comparative Example 2

[0054] (1) The ternary precursor Ni 0.9 Co 0.03 Mn 0.07(OH)2 is mixed with cerium oxide and lithium hydroxide and sintered in two stages. The first stage is sintered at a temperature of 500°C for 3 hours and the second stage is sintered at a temperature of 750°C for 10 hours to obtain a cerium-doped ternary positive electrode material Ce-NCM. The Ni 0.9 Co 0.03 Mn 0.07 The molar ratio of (OH)2 to lithium hydroxide is 1:1.045, and the amount of cerium oxide added is Ni 0.9 Co 0.03 Mn 0.07 0.1 wt% of (OH)2;

[0055] (2) The cerium-doped ternary cathode material Ce-NCM was mixed with a 3 wt% PVA solution in a mass ratio of 1:0.03 and stirred evenly. The stirring temperature was 10°C, the stirring speed was 300 r / min, and the stirring time was 15 min. The stirred mixture was mixed with ethanol in a volume ratio of 1:0.5 and precipitated for 2 h. After filtering and washing, it was dried at 120°C for 5 h to obtain a dry surface-coated cathode material Ce-PNCM.

[0056] (3) The surface-coated positive electrode material was mixed in a high-pressure mixer for 1 hour, subjected to a secondary heat treatment at 900°C for 3 hours under argon conditions, cooled naturally, and then sieved to obtain an ultra-high nickel positive electrode material.

[0057] The XRD diffraction peak intensity of the positive electrode material generated under the conditions of Example 2 and Comparative Example 1 (see Figure 2 ), indicating good crystallinity, with α-NaFeO structure, and obvious layered structure. The SEM image of Example 2 of the present invention (see Figure 1 ) shows that the surface coating layer of the positive electrode material is uniform as a whole, which can effectively isolate the interfacial side reactions between the positive electrode material and the electrolyte, the structural particles are complete, and the material uniformity is high.

[0058] The residual alkali results of Examples 1-4 of the present invention and Comparative Examples 1-2 are shown in Table 1, the conductivity is shown in Table 2, and the discharge performance is shown in Table 3.

[0059] Table 1 Comparison of residual alkali values ​​of different samples

[0060] name LiOH / % <![CDATA[Li2CO 3 / ％ ]]> Residual alkali Example 1 0.07 0.13 0.27 Example 2 0.07 0.18 0.35 Example 3 0.07 0.13 0.27 Example 4 0.09 0.19 0.38 Comparative Example 1 0.61 0.51 1.39 Comparative Example 2 0.25 0.38 0.84

[0061] Table 2 Comparison of conductivity of different samples

[0062]

[0063]

[0064] Table 3 Comparison of discharge performance of different samples

[0065]

[0066] As can be seen from Tables 1 to 3, the cerium-doped double-coated ultra-high nickel positive electrode material prepared by the method of the present invention has low surface residual alkali, improved conductivity, high discharge specific capacity, and better rate performance; the cycle performance test shows that the cycle performance is relatively excellent.

[0067] The above description is a detailed description of the preferred embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. Any equivalent changes or modifications completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for preparing an ultra-high nickel positive electrode material, characterized in that: The following steps are involved: (1) The ternary precursor is mixed with a cerium source and a lithium source, and a cerium-doped ternary cathode material Ce-NCM is obtained by a high-temperature solid-phase method; (2) The lanthanum source, zirconium source and other metal sources are ball-milled and mixed, and then heat-treated to obtain doped La2Zr 2- x M x O7, continue ball milling to obtain nano-scale La2Zr 2-x M x O7 ion conductor powder; (3) mixing the cerium-doped ternary cathode material Ce-NCM and the organic coating medium solution and stirring them uniformly, adding the stirred mixture into a second solvent for mixed precipitation, filtering, washing, and drying to obtain a dry surface-coated cathode material Ce-PNCM; (4) The nano-scale La2Zr prepared in step (2) 2-x M x O7 ion conductor powder is mixed with a dry surface-coated positive electrode material Ce-PNCM, and a secondary heat treatment is performed under protective gas conditions to obtain a cerium-doped double-coated ultra-high nickel positive electrode material.

2. The method for preparing the ultra-high nickel cathode material according to claim 1, wherein: In the step (1), the ternary precursor is Ni x Co y Mn z (OH)2, where x+y+z=1, x≥0.

9.

3. The method for preparing the ultra-high nickel positive electrode material according to claim 1, wherein: In the step (1), the molar ratio of the ternary precursor to the lithium source is 1:1.025-1.1, and the amount of the cerium source added is 0.1wt%-2wt% of the ternary precursor.

4. The method for preparing the ultra-high nickel positive electrode material according to claim 1, wherein: In the step (1), the cerium source is one of cerium oxide, cerium hydroxide, and cerium acetate hexahydrate, and the lithium source is LiOH or Li2CO3.

5. The method for preparing the ultra-high nickel positive electrode material according to claim 1, wherein: In the step (1), the high temperature solid phase method is a two-stage sintering process: the first stage sintering temperature is 420-600°C and the time is 1-3 hours; the second stage sintering temperature is 710-820°C and the time is 8-20 hours.

6. The method for preparing the ultra-high nickel cathode material according to claim 1, wherein: In the step (2), the lanthanum source is lanthanum oxide or lanthanum hydroxide, the zirconium source is one of zirconium oxide, zirconium hydroxide, and zirconium carbonate, and the metal source is one or more of Y2O3, Sc2O3, Er2O3, Gd2O3, Yb2O3, Nb2O3, WO3, MgO, and TiO2.

7. The method for preparing the ultra-high nickel cathode material according to claim 1, wherein: In the step (2), the molar ratio of the lanthanum source to the zirconium source is 1:1, and the amount of other metal sources added is 0-2 wt% of the total amount of the lanthanum source and the zirconium source.

8. The method for preparing the ultra-high nickel positive electrode material according to claim 1, wherein: In the step (3), the organic coating medium solution is a water-soluble carbon-based organic matter, and its concentration is 1wt%-15wt%.

9. The method for preparing the ultra-high nickel cathode material according to claim 1, wherein: In the step (3), the mass ratio of the organic coating medium solution to the cerium-doped ternary positive electrode material Ce-NCM is 1:0.01-0.

1.

10. The method for preparing the ultra-high nickel positive electrode material according to claim 1, wherein: In the step (3), the volume ratio of the mixed liquid to the second solvent is 1:0.3-1.5, and the second solvent is ethanol or propanol.

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