Ternary precursor sequentially coated with titanium and aluminum as well as preparation method and application of ternary precursor

Abstract

The invention provides a ternary precursor sequentially coated with titanium and aluminum and a preparation method and application thereof. The ternary precursor comprises a ternary precursor core, and the exterior of the ternary precursor core is sequentially coated with a titanium oxide middle layer and an Al (OH) 3 outer layer. The preparation method comprises the following steps: coating a ternary precursor core with a titanium oxide intermediate layer and an Al (OH) 3 outer layer to obtain a ternary precursor, calcining when the ternary positive electrode material is prepared, dehydrating the Al (OH) 3 outer layer to form an Al2O3 outer layer, inhibiting the volume expansion and shrinkage of the core in the ternary positive electrode material by the titanium oxide intermediate layer and the Al2O3 outer layer, and isolating the ternary positive electrode material from an electrolyte, so that the ternary positive electrode material is prepared. The surface side reaction of the ternary positive electrode material is inhibited; besides, through sequential coating of the titanium oxide intermediate layer and the Al2O3 outer layer, a continuous and defect-free compact layer formed during single coating of the titanium oxide intermediate layer and the Al2O3 outer layer can be avoided, so that lithium ion diffusion is facilitated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and relates to a ternary precursor coated with titanium and aluminum in sequence, in particular to a ternary precursor coated with titanium and aluminum in sequence and a preparation method and application thereof. BACKGROUND

[0002] With the wide application of lithium ion batteries, the development of high-performance electrode materials has become a research hotspot. High-nickel ternary precursors (such as: Ni 0.90 Co 0.05 Mn 0.05 OH) are widely used in battery positive electrode materials due to their high capacity and low cost. However, such materials have problems such as structural instability and easy occurrence of surface side reactions under high temperature and high voltage conditions, which affect the cycle life and safety of the battery. In the prior art, the performance of the ternary precursor is improved by element doping, nanocrystallization and concentration gradient design, so as to improve the problems of structural instability and easy occurrence of surface side reactions of the ternary positive electrode material.

[0003] The element doping in the prior art can significantly improve the electrochemical performance and cycle stability of the ternary positive electrode material, but the doping process has the risk of excessive doping, and it is difficult to prepare a ternary positive electrode material with high uniformity, and the preparation cost is high.

[0004] The nanocrystallization technology in the prior art can increase the specific surface area of the ternary positive electrode material, promote the rapid diffusion of lithium ions, and improve the high-rate discharge performance, but the synthesis conditions of the ternary positive electrode material synthesized by the nanocrystallization technology are difficult to control.

[0005] The concentration gradient in the prior art can improve the performance and stability of the battery, but the preparation process is difficult, it is difficult to control the uniformity of the ternary positive electrode material, and the preparation cost will be greatly increased, which seriously limits its large-scale production.

[0006] Based on the above solutions, it is difficult to improve the structural stability of the ternary positive electrode material without affecting the preparation cost and other performances of the ternary positive electrode material, and to improve the surface side reaction of the positive electrode material. In the prior art, a protective layer is coated on the surface of the ternary precursor to improve the performance of the ternary precursor. However, although the surface coating can improve the interface performance and prevent dissolution and delithiation, and can also isolate the positive active material from the electrolyte, the dense layer formed by the uniform coating will hinder the diffusion of lithium ions, thereby causing the performance of the battery prepared from the ternary positive electrode material to decrease.

[0007] CN115872459A discloses a double-layer coated ternary precursor and a preparation method and application thereof. The double-layer coated ternary precursor comprises an inner core, an inner coating layer coated on the outer surface of the inner core, and an outer coating layer coated on the outer surface of the inner coating layer; wherein the inner core comprises a ternary hydroxide, the inner coating layer comprises a ternary carbonate, and the outer coating layer comprises at least one of aluminum hydroxide, magnesium hydroxide, and titanium hydroxide.

[0008] CN112490428A discloses a pretreatment method of a ternary precursor, a product thereof, and an application thereof. The pretreatment method of the ternary precursor mixes the ternary precursor with an oxidizing agent to perform a pre-oxidation reaction to obtain a pre-oxidized ternary precursor. The method effectively reduces the temperature of subsequent lithium treatment of the precursor, thereby realizing one-step calcination to prepare a coated and doped modified ternary positive electrode material.

[0009] CN110061226A discloses a titanium suboxide coated positive electrode material, a preparation method of the positive electrode material, and a lithium ion battery. The positive electrode material is coated with titanium suboxide on the surface, and the chemical formula is LiNi 0.5 Co 0.2 Mn 0.3 O2 / Ti4O7. The preparation method comprises: mixing a lithium source with a ternary precursor uniformly, then sintering, cooling, crushing, and sieving to obtain LiNi 0.5 Co 0.2 Mn 0.3 O2; dissolving TiCl4 in water, and introducing ammonia to obtain a titanium oxide sol; adding LiNi 0.5 Co 0.2 Mn 0.3 O2 into the titanium oxide sol, and then performing hydrolysis precipitation, filtration, drying, sintering, and cooling to obtain a titanium suboxide coated modified positive electrode material.

[0010] The ternary precursors disclosed in the prior art have certain defects, and there are problems of unstable structure and easy occurrence of surface side reactions of the ternary positive electrode material prepared from the ternary precursors. Moreover, the methods in the prior art are difficult to improve the structural stability of the ternary positive electrode material without affecting the preparation cost and other properties of the ternary positive electrode material. Therefore, it is crucial to develop and design a new type of ternary precursor, a preparation method thereof, and an application thereof. SUMMARY

[0011] In view of the deficiencies in the prior art, the purpose of the present application is to provide a titanium-aluminum sequentially coated ternary precursor and a preparation method and application thereof, in the present application, the ternary precursor core is coated with a titanium oxide intermediate layer and an Al(OH)3 outer layer to obtain a titanium-aluminum sequentially coated ternary precursor, and when the ternary positive electrode material is prepared, the Al(OH)3 outer layer will dehydrate to form an Al2O3 outer layer, the titanium oxide intermediate layer and the Al2O3 outer layer inhibit the volume expansion and shrinkage of the inner core in the ternary positive electrode material, realize the isolation of the ternary positive electrode material and the electrolyte, and inhibit the surface side reaction of the ternary positive electrode material; in addition, through the sequential coating of the titanium oxide intermediate layer and the Al2O3 outer layer, the continuous defect-free dense layer formed by the single coating of the titanium oxide intermediate layer and the Al2O3 outer layer can be avoided, thereby being beneficial to the diffusion of lithium ions; therefore, the ternary precursor and the ternary positive electrode material prepared therefrom have high structural stability and surface chemical stability, and also have good lithium ion diffusion performance.

[0012] To achieve this purpose, the present application adopts the following technical solutions:

[0013] In a first aspect, the present application provides a titanium-aluminum sequentially coated ternary precursor, which comprises a ternary precursor core, and the ternary precursor core is sequentially coated with a titanium oxide intermediate layer and an Al(OH)3 outer layer.

[0014] Although simple TiO2 coating and Al2O3 coating can improve the structural stability and surface stability of the ternary precursor, thereby improving the stability of the ternary positive electrode material, the single homogeneous coating of Al2O3 or TiO2 is easy to form a dense layer, which hinders the diffusion of lithium ions, thereby causing the performance of the battery prepared from the ternary positive electrode material to partially decrease.

[0015] In the present application, the ternary precursor core is coated with a titanium oxide intermediate layer and an Al(OH)3 outer layer to obtain a ternary precursor coated with titanium and aluminum in turn. When the ternary positive electrode material is prepared from the ternary precursor, calcination is required. The Al(OH)3 outer layer will dehydrate to form an Al2O3 outer layer. The titanium oxide intermediate layer and the Al2O3 outer layer can inhibit the volume expansion and shrinkage of the inner core of the ternary positive electrode material, thereby improving the structural stability of the ternary positive electrode material. In addition, due to the coating of the titanium oxide intermediate layer and the Al2O3 outer layer, the inner core of the ternary positive electrode material is isolated from the electrolyte. The interface performance is improved, the dissolution and delithiation are inhibited, and the surface side reaction of the ternary positive electrode material is inhibited. In addition, through the sequential coating of the titanium oxide intermediate layer and the Al2O3 outer layer, a continuous defect-free dense layer formed by single coating of the titanium oxide intermediate layer and the Al2O3 outer layer can be avoided, thereby facilitating lithium ion diffusion. Therefore, the ternary precursor and the ternary positive electrode material prepared therefrom have high structural stability and surface chemical stability, and also have good lithium ion diffusion performance. The battery prepared from the ternary positive electrode material exhibits good rate performance and cycle stability.

[0016] Preferably, the porosity of the ternary precursor core is 10% to 20%, for example, it can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, but is not limited to the listed values. Other values not listed in this range are also applicable.

[0017] In the present application, the ternary precursor core has a high porosity, so the ternary positive electrode material prepared from the ternary precursor has a large number of interconnected pores inside, which can shorten the lithium ion diffusion distance, enhance the contact between the electrolyte and the inside of the ternary positive electrode material, accelerate lithium ion transport, and significantly improve the rate performance of the battery. In addition, the pores of the ternary positive electrode material can act as a buffer space to relieve the volume expansion stress during charging and discharging, reduce particle cracking, and improve the cycle stability.

[0018] Preferably, the D50 particle size of the ternary precursor core is 2.5 μm to 4 μm, for example, it can be 2.5 μm, 2.7 μm, 2.9 μm, 3.1 μm, 3.3 μm, 3.5 μm, 3.7 μm, 3.9 μm or 4.0 μm, but is not limited to the listed values. Other values not listed in this range are also applicable.

[0019] Preferably, the thickness of the titanium oxide intermediate layer is 5 nm to 20 nm, for example, it can be 5 nm, 7 nm, 9 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm or 20 nm, but is not limited to the listed values. Other values not listed in this range are also applicable.

[0020] Preferably, the thickness of the Al(OH)3 outer layer is 5 nm to 20 nm, for example, it can be 5 nm, 7 nm, 9 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm or 20 nm, but not limited to the listed values, and other values not listed within the range are also applicable.

[0021] Preferably, the titanium oxide in the titanium oxide intermediate layer comprises amorphous TiO2·xH2O, wherein x is 0.5 to 2; the ratio of the molar amount of TiO2 in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:(0.2 to 1), for example, it can be 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9 or 1:1, but not limited to the listed values, and other values not listed within the range are also applicable.

[0022] In the present application, x is 0.5 to 2, and x can be, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0, but not limited to the listed values, and other values not listed within the range are also applicable.

[0023] In the present application, in the process of preparing the ternary positive electrode material from the ternary precursor, since the dehydration temperature of amorphous TiO2·xH2O is higher than the temperature of heat treatment, TiO2·xH2O will not undergo dehydration.

[0024] In a second aspect, the present application provides a preparation method of the ternary precursor of the first aspect, the preparation method comprising:

[0025] (1) performing a first co-precipitation reaction in a reaction solution to obtain a solution containing a ternary precursor core;

[0026] (2) performing mother liquor replacement on the solution containing the ternary precursor core obtained in step (1), adjusting the pH of the reaction solution, adding a titanium salt solution, and performing a second co-precipitation reaction to obtain a solution containing a precipitate;

[0027] (3) adjusting the pH of the solution containing the precipitate obtained in step (2), adding an aluminum salt solution, and performing a second co-precipitation reaction to obtain a ternary precursor.

[0028] Preferably, in the first co-precipitation reaction of step (1), the nickel-cobalt-manganese mixed salt solution, the precipitant solution and the complexing agent solution are added into the reaction bottom solution in parallel flow to form a reaction solution.

[0029] Preferably, the total concentration of metal ions in the nickel-cobalt-manganese mixed salt solution is in the range of 80 g / L to 120 g / L, such as 80 g / L, 85 g / L, 90 g / L, 95 g / L, 100 g / L, 105 g / L, 110 g / L, 115 g / L, or 120 g / L, but not limited to the listed values, other values not listed within the range are also applicable.

[0030] Preferably, the nickel ions in the nickel-cobalt-manganese mixed salt solution account for at least 90% of the total molar amount of metal ions, such as 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%, but not limited to the listed values, other values not listed within the range are also applicable, the rest being cobalt ions and manganese ions.

[0031] Preferably, the mass concentration of the precipitant in the precipitant solution is in the range of 28 wt% to 32 wt%, such as 28 wt%, 28.5 wt%, 29 wt%, 29.5 wt%, 30 wt%, 30.5 wt%, 31 wt%, 31.5 wt%, or 32 wt%, but not limited to the listed values, other values not listed within the range are also applicable.

[0032] Preferably, the precipitant in the precipitant solution includes any one or a combination of at least two of sodium hydroxide, potassium hydroxide, sodium carbonate, or sodium bicarbonate, typical but non-limiting combinations include a combination of sodium hydroxide and potassium hydroxide, a combination of sodium carbonate and sodium bicarbonate, a combination of sodium hydroxide and sodium carbonate, a combination of potassium hydroxide and sodium bicarbonate, or a combination of sodium hydroxide, sodium carbonate, and sodium bicarbonate.

[0033] Preferably, the mass concentration of the complexing agent in the complexing agent solution is in the range of 10 wt% to 20 wt%, such as 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, or 20 wt%, but not limited to the listed values, other values not listed within the range are also applicable.

[0034] Preferably, the complexing agent in the complexing agent solution includes any one or a combination of at least two of ammonia, aqueous ammonia, ethylenediamine, diethylenetriamine, triethylenetetramine, ethylenediaminetetraacetic acid, citric acid, tartaric acid, sodium gluconate, amino triacetic acid, or nitrilotriacetic acid, typical but non-limiting combinations include a combination of aqueous ammonia and ethylenediamine, a combination of ethylenediaminetetraacetic acid and citric acid, a combination of tartaric acid and sodium gluconate, a combination of amino triacetic acid and nitrilotriacetic acid, a combination of ethylenediamine, diethylenetriamine, and triethylenetetramine, or a combination of aqueous ammonia, ethylenediaminetetraacetic acid, and citric acid.

[0035] Preferably, the flow rate of the nickel-cobalt-manganese mixed salt solution in the parallel flow addition is 6L / h-10L / h, for example, it can be 6L / h, 6.5L / h, 7L / h, 7.5L / h, 8L / h, 8.5L / h, 9L / h, 9.5L / h or 10L / h, but not only limited to the listed values, other values not listed in the range are also applicable.

[0036] Preferably, the flow rate of the precipitant solution in the parallel flow addition is 2L / h-3L / h, for example, it can be 2L / h, 2.1L / h, 2.2L / h, 2.3L / h, 2.4L / h, 2.5L / h, 2.6L / h, 2.7L / h, 2.8L / h, 2.9L / h or 3L / h, but not only limited to the listed values, other values not listed in the range are also applicable.

[0037] Preferably, the flow rate of the complexing agent solution in the parallel flow addition is 0.6L / h-1L / h, for example, it can be 0.6L / h, 0.65L / h, 0.7L / h, 0.75L / h, 0.8L / h, 0.85L / h, 0.9L / h, 0.95L / h or 1L / h, but not only limited to the listed values, other values not listed in the range are also applicable.

[0038] Preferably, the temperature of the reaction base solution is 40-60℃, the concentration of the complexing agent is 4-8g / L, and the pH is 10.0-12.0.

[0039] In the present application, the temperature of the reaction base solution is 40-60℃, for example, it can be 40℃, 42℃, 44℃, 46℃, 48℃, 50℃, 52℃, 54℃, 56℃, 58℃ or 60℃, but not only limited to the listed values, other values not listed in the range are also applicable.

[0040] In the present application, the concentration of the complexing agent in the reaction base solution is 4-8g / L, for example, it can be 4g / L, 4.5g / L, 5g / L, 5.5g / L, 6g / L, 6.5g / L, 7g / L, 7.5g / L or 8g / L, but not only limited to the listed values, other values not listed in the range are also applicable.

[0041] In the present application, the pH of the reaction base solution is 10.0-12.0, for example, it can be 10.0, 10.2, 10.4, 10.6, 10.8, 11.0, 11.2, 11.4, 11.6, 11.8 or 12.0, but not only limited to the listed values, other values not listed in the range are also applicable.

[0042] Preferably, the first co-precipitation reaction in step (1) is accompanied by stirring at a rotation speed of 200 r / min to 400 r / min, for example, 200 r / min, 220 r / min, 240 r / min, 260 r / min, 280 r / min, 300 r / min, 320 r / min, 340 r / min, 360 r / min, 380 r / min or 400 r / min, but not limited to the listed values, and other values not listed in the range are also applicable.

[0043] Preferably, the temperature of the reaction solution in the first co-precipitation reaction in step (1) is controlled at 40°C to 60°C, the concentration of the complexing agent is 4 g / L to 8 g / L, and the pH is 10.0 to 12.0.

[0044] In the present application, the temperature of the reaction solution in the first co-precipitation reaction in step (1) is controlled at 40°C to 60°C, for example, 40°C, 42°C, 44°C, 46°C, 48°C, 50°C, 52°C, 54°C, 56°C, 58°C or 60°C, but not limited to the listed values, and other values not listed in the range are also applicable.

[0045] In the present application, the concentration of the complexing agent in the reaction solution in the first co-precipitation reaction in step (1) is controlled at 4 g / L to 8 g / L, for example, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L or 8 g / L, but not limited to the listed values, and other values not listed in the range are also applicable.

[0046] In the present application, the pH of the reaction solution in the first co-precipitation reaction in step (1) is controlled at 10.0 to 12.0, for example, 10.0, 10.2, 10.4, 10.6, 10.8, 11.0, 11.2, 11.4, 11.6, 11.8 or 12.0, but not limited to the listed values, and other values not listed in the range are also applicable.

[0047] Preferably, during the first co-precipitation reaction in step (1), gas is introduced into the reaction solution to form micro-bubbles in the reaction solution.

[0048] In the present application, by forming micro-bubbles in the reaction solution, the ternary precursor nuclei formed after the first co-precipitation reaction have higher porosity.

[0049] Preferably, the average diameter size of the microbubbles is 10 μm to 100 μm, for example, can be 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm or 100 μm, but not limited to the listed values, other values not listed in the range are also applicable.

[0050] Preferably, the flow rate of the gas is controlled to be 0.5 L / min to 2 L / min, for example, can be 0.5 L / min, 0.7 L / min, 0.9 L / min, 1.1 L / min, 1.3 L / min, 1.5 L / min, 1.7 L / min, 1.9 L / min or 2.0 L / min, but not limited to the listed values, other values not listed in the range are also applicable.

[0051] Preferably, the gas comprises nitrogen and / or inert gas.

[0052] Preferably, the mother liquor replacement comprises: washing the solution containing ternary precursor core obtained in step (1) to obtain the reaction solution of step (2).

[0053] In the present application, the washing is: adding clean water through the water adding pipe of the thickener at a flow rate of 40 L / h to 60 L / h, and the slurry is separated from the clean liquid through the clean liquid outlet during the circulation, so as to realize the mother liquor replacement.

[0054] In the present application, the clean water is added through the water adding pipe of the thickener at a flow rate of 40 L / h to 60 L / h, for example, can be 40 L / h, 42 L / h, 44 L / h, 46 L / h, 48 L / h, 50 L / h, 52 L / h, 54 L / h, 56 L / h, 58 L / h or 60 L / h, but not limited to the listed values, other values not listed in the range are also applicable.

[0055] Preferably, the pH of the reaction solution in step (2) is adjusted to be 3 to 4, for example, can be 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 or 4.0, but not limited to the listed values, other values not listed in the range are also applicable.

[0056] Preferably, the concentration of the titanium salt in the titanium salt solution in step (2) is 0.05-0.2 mol / L, for example, it can be 0.05, 0.07, 0.09, 0.11, 0.13, 0.15, 0.17, 0.19 or 0.20 mol / L, but is not limited to the listed values, and other values not listed within the range are also applicable.

[0057] Preferably, the flow rate of the titanium salt solution added to the reaction solution in step (2) is 6-18 mL / h, for example, it can be 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 mL / h, but is not limited to the listed values, and other values not listed within the range are also applicable.

[0058] Preferably, the titanium salt in the titanium salt solution in step (2) comprises Ti(SO4)2 and / or TiOSO4.

[0059] Preferably, the second co-precipitation reaction in step (2) is accompanied by stirring at a speed of 200-400 r / min, for example, it can be 200, 220, 240, 260, 280, 300, 320, 340, 360, 380 or 400 r / min, but is not limited to the listed values, and other values not listed within the range are also applicable.

[0060] Preferably, the pH of the solution containing the precipitate obtained in step (2) is adjusted to 8.5-9.5 in step (3), for example, it can be 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4 or 9.5, but is not limited to the listed values, and other values not listed within the range are also applicable.

[0061] Preferably, the concentration of the aluminum salt solution in step (3) is 0.02-0.1 mol / L, for example, it can be 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.10 mol / L, but is not limited to the listed values, and other values not listed within the range are also applicable.

[0062] Preferably, the flow rate of the addition of the aluminum salt solution in step (3) is 3 mL / h to 9 mL / h, for example, it can be 3 mL / h, 3.5 mL / h, 4 mL / h, 4.5 mL / h, 5 mL / h, 5.5 mL / h, 6 mL / h, 6.5 mL / h, 7 mL / h, 7.5 mL / h, 8 mL / h, 8.5 mL / h, or 9 mL / h, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0063] Preferably, the aluminum salt in the aluminum salt solution in step (3) includes NaAlO2 and / or Al2(SO4)3.

[0064] Preferably, the third co-precipitation reaction in step (3) is accompanied by stirring at a speed of 150 r / min to 250 r / min, for example, it can be 150 r / min, 160 r / min, 170 r / min, 180 r / min, 190 r / min, 200 r / min, 210 r / min, 220 r / min, 230 r / min, 240 r / min, or 250 r / min, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0065] Preferably, step (3) further includes centrifugation, washing, and drying, which are sequentially performed after the third co-precipitation reaction.

[0066] Preferably, the drying temperature is 100℃ to 150℃, for example, it can be 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, or 150℃, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0067] As a preferred technical solution of the preparation method of the present application, the preparation method comprises:

[0068] (1) adding a nickel-cobalt-manganese mixed salt solution with a total concentration of metal ions of 80 to 120 g / L (flow rate of 6 L / h to 10 L / h), a precipitant solution with a mass concentration of 28 wt% to 32 wt%, and a complexing agent solution with a mass concentration of 10 wt% to 20 wt% into a reaction bottom solution with a temperature of 40℃ to 60℃, a complexing agent concentration of 4 g / L to 8 g / L, and a pH of 10.0 to 12.0 to form a reaction solution, controlling the temperature of the reaction solution to be 40℃ to 60℃, the complexing agent concentration to be 4 g / L to 8 g / L, and the pH to be 10.0 to 12.0, and stirring at a speed of 200 r / min to 400 r / min to perform a first co-precipitation reaction in the reaction solution to obtain a solution containing ternary precursor nuclei;

[0069] In the first co-precipitation reaction, nitrogen and / or inert gas is introduced into the reaction solution at a flow rate of 0.5 L / min to 2 L / min, and micro-bubbles with an average diameter of 10 μm to 100 μm are formed in the reaction solution;

[0070] (2) The solution containing the ternary precursor core obtained in step (1) is subjected to water washing to obtain a reaction solution, the pH of the reaction solution is adjusted to 3 to 4, a Ti(SO4)2 solution with a concentration of 0.05 mol / L to 0.2 mol / L is added at a flow rate of 6 mL / h to 18 mL / h, and stirring is performed at a rotation speed of 200 r / min to 400 r / min, a second co-precipitation reaction is performed, and a solution containing precipitates is obtained;

[0071] (3) The pH of the solution containing the precipitates obtained in step (2) is adjusted to 8.5 to 9.5, an aluminum salt solution with a concentration of 0.02 mol / L to 0.1 mol / L is added at a flow rate of 3 mL / h to 9 mL / h, and stirring is performed at a rotation speed of 150 r / min to 250 r / min, a third co-precipitation reaction is performed, and then centrifugation and washing are sequentially performed, the obtained solid is dried at a temperature of 100 ℃ to 150 ℃, and a ternary precursor is obtained.

[0072] In a third aspect, the present application provides a ternary positive electrode material, which is prepared from raw materials including the ternary precursor of the first aspect.

[0073] In a fourth aspect, the present application provides a battery, which includes the ternary positive electrode material of the third aspect.

[0074] The numerical ranges described in the present application include not only the point values recited above, but also any point values between the recited values, which are not specifically recited. Due to the length and in the interest of brevity, the present application does not recite all the specific point values included in the ranges.

[0075] Compared with the prior art, the present application has the following beneficial effects:

[0076] In the present application, the ternary precursor core is coated with a titanium oxide intermediate layer and an Al(OH)3outer layer to obtain a ternary precursor coated with titanium and aluminum in sequence. When the ternary positive electrode material is prepared from the ternary precursor, calcination is required. The Al(OH)3outer layer will dehydrate to form an Al2O3outer layer. The titanium oxide intermediate layer and the Al2O3outer layer can inhibit the volume expansion and shrinkage of the inner core of the ternary positive electrode material, thereby improving the structural stability of the ternary positive electrode material. In addition, due to the coating of the titanium oxide intermediate layer and the Al2O3outer layer, the inner core of the ternary positive electrode material is isolated from the electrolyte. At the same time of improving the interface performance and inhibiting dissolution and delithiation, the surface side reaction of the ternary positive electrode material is inhibited. In addition, through the sequential coating of the titanium oxide intermediate layer and the Al2O3outer layer, a continuous defect-free dense layer formed by the single coating of the titanium oxide intermediate layer and the Al2O3outer layer can be avoided, thereby being beneficial to lithium ion diffusion. Therefore, the ternary precursor and the ternary positive electrode material prepared therefrom have high structural stability and surface chemical stability, and also have good lithium ion diffusion performance. The battery prepared from the ternary positive electrode material exhibits good rate performance and cycle stability. BRIEF DESCRIPTION OF DRAWINGS

[0077] Figure 1 FIG. 1 is an SEM image of the titanium-aluminum sequentially coated ternary precursor provided in Example 1. DETAILED DESCRIPTION

[0078] The technical solutions of the present application will be further described through specific embodiments. Those skilled in the art should understand that the embodiments are only to help understand the present application and should not be regarded as specific limitations on the present application.

[0079] Example 1

[0080] The present embodiment provides a titanium-aluminum sequentially coated ternary precursor. The ternary precursor includes a ternary precursor core with a porosity of 15% and a D50 particle size of 3.2 μm. The ternary precursor core is sequentially coated with a titanium oxide intermediate layer with a thickness of 12 nm and an Al(OH)3outer layer with a thickness of 12 nm. The titanium oxide in the titanium oxide intermediate layer is amorphous TiO2·xH2O, where x is 1.2. The ratio of the molar amount of TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3in the Al(OH)3outer layer is 1:0.85.

[0081] The preparation method of the ternary precursor is as follows:

[0082] (1) adding a nickel-cobalt-manganese mixed salt solution (the nickel-cobalt-manganese mixed salt solution is obtained by mixing nickel sulfate, cobalt sulfate, manganese sulfate and water, and the flow rate of the nickel-cobalt-manganese mixed salt solution added into the reaction bottom solution is 8 L / h) with a total concentration of metal ions of 100 g / L and a molar ratio of nickel ions, cobalt ions and manganese ions of 0.94:0.3:0.3, a sodium hydroxide solution with a mass concentration of 30 wt% and an ammonia water with a mass concentration of 15 wt% into a reaction bottom solution with a temperature of 50°C, an ammonia concentration of 6 g / L and a pH of 11.0 in a concurrent flow to form a reaction solution, controlling the temperature of the reaction solution to be 50°C, the ammonia concentration to be 6 g / L and the pH to be 11.0, and stirring at a rotating speed of 300 r / min to perform a first co-precipitation reaction in the reaction solution to obtain a solution containing ternary precursor cores;

[0083] During the first co-precipitation reaction, nitrogen gas is introduced into the reaction solution at a flow rate of 1.2 L / min to form micro-bubbles with an average diameter of 55 μm in the reaction solution;

[0084] (2) performing water washing on the solution containing ternary precursor cores obtained in step (1) to obtain a reaction solution, adjusting the pH of the reaction solution to be 3.5, adding a Ti(SO4)2 solution with a concentration of 0.1 mol / L at a flow rate of 12 mL / h, and stirring at a rotating speed of 300 r / min to perform a second co-precipitation reaction to obtain a solution containing precipitates;

[0085] (3) adjusting the pH of the solution containing precipitates obtained in step (2) to be 9.0, adding a NaAlO2 solution with a concentration of 0.06 mol / L at a flow rate of 6 mL / h, and stirring at a rotating speed of 200 r / min to perform a third co-precipitation reaction, then sequentially performing centrifugation and washing, and drying the obtained solid at a temperature of 120°C to obtain a ternary precursor.

[0086] A scanning electron microscope is used to observe the titanium-aluminum sequentially coated ternary precursor provided in the embodiment, and a SEM image of the titanium-aluminum sequentially coated ternary precursor is as shown in FIG. 1. Figure 1

[0087] Example 2

[0088] The embodiment provides a titanium-aluminum sequentially coated ternary precursor, the ternary precursor comprising a ternary precursor core with a porosity of 10% and a D50 particle size of 2.5 μm, and an outer portion of the ternary precursor core sequentially coated with a titanium oxide intermediate layer with a thickness of 5 nm and an Al(OH)3 outer layer with a thickness of 5 nm; the titanium oxide in the titanium oxide intermediate layer is amorphous TiO2·xH2O, wherein x is 1; and the ratio of the molar amount of TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:1. ​

[0089] The preparation method of the ternary precursor is as follows:

[0090] (1) A nickel-cobalt-manganese mixed salt solution with a total concentration of metal ions of 80 g / L and a molar ratio of nickel ions, cobalt ions and manganese ions of 0.94:0.3:0.3 (the nickel-cobalt-manganese mixed salt solution is obtained by mixing nickel sulfate, cobalt sulfate, manganese sulfate and water, and the flow rate of the nickel-cobalt-manganese mixed salt solution added into the reaction bottom solution is 6 L / h), a sodium hydroxide solution with a mass concentration of 28 wt%, and an ammonia water with a mass concentration of 10 wt% are added into a reaction bottom solution with a temperature of 60°C, an ammonia concentration of 4 g / L and a pH of 10.0 in a concurrent flow manner to form a reaction solution, the temperature of the reaction solution is controlled to be 60°C, the ammonia concentration is controlled to be 4 g / L, the pH is controlled to be 10.0, and the reaction solution is stirred at a speed of 400 r / min to perform a first co-precipitation reaction in the reaction solution to obtain a solution containing ternary precursor nuclei;

[0091] During the first co-precipitation reaction, nitrogen gas is introduced into the reaction solution at a flow rate of 0.5 L / min to form micro-bubbles with an average diameter of 10 μm in the reaction solution;

[0092] (2) The solution containing ternary precursor nuclei obtained in step (1) is subjected to water washing to obtain a reaction solution, the pH of the reaction solution is adjusted to be 4, a Ti(SO4)2 solution with a concentration of 0.05 mol / L is added into the reaction solution at a flow rate of 6 mL / h, and the reaction solution is stirred at a speed of 200 r / min to perform a second co-precipitation reaction to obtain a solution containing precipitates;

[0093] (3) The pH of the solution containing precipitates obtained in step (2) is adjusted to be 9.5, a NaAlO2 solution with a concentration of 0.1 mol / L is added into the solution at a flow rate of 9 mL / h, and the solution is stirred at a speed of 250 r / min to perform a third co-precipitation reaction, then centrifugation and washing are sequentially performed, and the obtained solid is dried at a temperature of 100°C to obtain the ternary precursor.

[0094] Example 3

[0095] The present embodiment provides a ternary precursor coated with titanium and aluminum in sequence, which comprises a ternary precursor nucleus with a porosity of 20% and a D50 particle size of 4 μm, and the ternary precursor nucleus is coated with a titanium oxide intermediate layer with a thickness of 20 nm and an Al(OH)3 outer layer with a thickness of 13 nm in sequence; the titanium oxide in the titanium oxide intermediate layer is amorphous TiO2·xH2O, wherein x is 1.5; the ratio of the molar amount of TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:0.2.

[0096] The preparation method of the ternary precursor is as follows:

[0097] (1) adding a nickel-cobalt-manganese mixed salt solution (the nickel-cobalt-manganese mixed salt solution is obtained by mixing nickel sulfate, cobalt sulfate, manganese sulfate and water, and the flow rate of the nickel-cobalt-manganese mixed salt solution added into the reaction solution is 10 L / h) with a total concentration of metal ions of 120 g / L and a molar ratio of nickel ions, cobalt ions and manganese ions of 0.94:0.3:0.3, a sodium hydroxide solution with a mass concentration of 32 wt%, and an ammonia water with a mass concentration of 20 wt% into a reaction solution with a temperature of 40°C, an ammonia concentration of 8 g / L and a pH of 12.0 in a concurrent flow manner to form a reaction solution, controlling the temperature of the reaction solution to be 40°C, the ammonia concentration to be 8 g / L, and the pH to be 12.0, and stirring at a rotating speed of 200 r / min to perform a first co-precipitation reaction in the reaction solution to obtain a solution containing ternary precursor nuclei;

[0098] In the process of the first co-precipitation reaction, nitrogen gas is introduced into the reaction solution at a flow rate of 2 L / min to form micro-bubbles with an average diameter of 100 μm in the reaction solution;

[0099] (2) performing water washing on the solution containing ternary precursor nuclei obtained in step (1) to obtain a reaction solution, adjusting the pH of the reaction solution to be 3, adding a Ti(SO4)2 solution with a concentration of 0.2 mol / L at a flow rate of 18 mL / h, and stirring at a rotating speed of 400 r / min to perform a second co-precipitation reaction to obtain a solution containing precipitates;

[0100] (3) adjusting the pH of the solution containing precipitates obtained in step (2) to be 8.5, adding a NaAlO2 solution with a concentration of 0.02 mol / L at a flow rate of 3 mL / h, and stirring at a rotating speed of 150 r / min to perform a third co-precipitation reaction, then sequentially performing centrifugation and washing, and drying the obtained solid at a temperature of 150°C to obtain a ternary precursor.

[0101] Example 4

[0102] The present embodiment provides a ternary precursor coated with titanium and aluminum in sequence, wherein the porosity of the ternary precursor nuclei is 5%.

[0103] That is, nitrogen gas is not introduced into the reaction solution to form micro-bubbles in the reaction solution in step (1) of the preparation method of the ternary precursor, and the rest is the same as that in Example 3.

[0104] Example 5

[0105] The present embodiment provides a ternary precursor coated with titanium and aluminum in sequence, wherein the porosity of the ternary precursor nuclei is 32%.

[0106] That is, in addition to omitting the step of passing nitrogen gas into the reaction solution at a flow rate of 4 L / min in step (1) of the preparation method of the ternary precursor, the average diameter size of the microbubbles formed in the reaction solution is 180 μm, and the rest is the same as in Example 3.

[0107] Example 6

[0108] This example provides a ternary precursor coated with titanium and aluminum in sequence, except that the ratio of the molar amount of amorphous TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:0.1; that is, the thickness of the titanium oxide intermediate layer is 20 nm, and the thickness of the Al(OH)3 outer layer is 1.8 nm, and the rest is the same as in Example 3.

[0109] Example 7

[0110] This example provides a ternary precursor coated with titanium and aluminum in sequence, except that the ratio of the molar amount of amorphous TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:1.5; that is, the thickness of the titanium oxide intermediate layer is 20 nm, and the thickness of the Al(OH)3 outer layer is 27 nm, and the rest is the same as in Example 3.

[0111] Example 8

[0112] This example provides a ternary precursor coated with titanium and aluminum in sequence, except that the pH of the reaction solution in step (2) of the preparation method of the ternary precursor is 2, and the rest is the same as in Example 3.

[0113] Example 9

[0114] This example provides a ternary precursor coated with titanium and aluminum in sequence, except that the pH of the reaction solution in step (2) of the preparation method of the ternary precursor is 5, and the rest is the same as in Example 3.

[0115] Comparative Example 1

[0116] This comparative example provides a ternary precursor coated with titanium and aluminum in sequence, except that the titanium oxide intermediate layer of the outer coating of the ternary precursor core is omitted, and the thickness of the Al(OH)3 outer layer is 25 nm.

[0117] That is, in addition to omitting the step of passing nitrogen gas into the reaction solution at a flow rate of 4 L / min in step (1) of the preparation method of the ternary precursor, the average diameter size of the microbubbles formed in the reaction solution is 180 μm, and the rest is the same as in Example 3.

[0118] Comparative Example 2

[0119] The comparative example provides a ternary precursor coated with titanium and aluminum in sequence, except that the outer Al(OH)3 layer of the ternary precursor core is omitted, and the thickness of the titanium oxide intermediate layer is 25 nm.

[0120] That is, step (3) of the preparation method of the ternary precursor is omitted, and the rest is the same as Example 3.

[0121] Comparative Example 3

[0122] The comparative example provides a ternary precursor coated with titanium and aluminum in sequence, except that the outer Al(OH)3 layer of the ternary precursor core is omitted, and the thickness of the titanium oxide intermediate layer is 25 nm.

[0123] That is, step (3) of the preparation method of the ternary precursor is omitted, and the rest is the same as Example 3.

[0124] The ternary precursors provided in the above examples and comparative examples are mixed with lithium hydroxide, and then heat treated at 600°C for 250 min to obtain a ternary positive electrode material; a lithium ion battery is prepared using the obtained ternary positive electrode material: the obtained ternary positive electrode material, conductive carbon black SP (TIMCAL), and polyvinylidene fluoride PVDF (HSV900) are mixed in a mass ratio of 90:5:5, a solvent is N-methyl pyrrolidone, the mixture is stirred into a slurry, and the obtained slurry is uniformly coated on an aluminum foil using a doctor blade with a coating gap of 100 um; after coating, it is first dried by blowing air, then roll-pressed and cut into a circular electrode sheet, and then vacuum dried at 120°C to weigh the electrode sheet to obtain a button half-battery positive electrode sheet; the negative electrode is selected to be a metal lithium sheet, the separator is selected to be a PP microporous membrane, and the electrolyte is selected to be a lithium battery basic electrolyte; the positive electrode sheet, the metal lithium sheet, the separator, and the electrolyte are assembled to obtain a button cell.

[0125] The obtained button cell is charged and discharged at 0.1C / 0.1C, and the charge and discharge test is carried out in a voltage window of 2.8-4.3V; the 0.1C rate performance and the capacity retention rate after 100 cycles of the button cell are shown in Table 1.

[0126] Table 1

[0127] 0.1C rate (mAh / g) Capacity retention (%) Example 1 198 92.5 Example 2 195 91.8 Example 3 203 93.2 Example 4 182 85.0 Example 5 196 87.5 Example 6 189 88.7 Example 7 192 89.5 Example 8 185 82.0 Example 9 190 86.3 Comparative Example 1 175 78.0 Comparative Example 2 188 75.5 Comparative Example 3 205 68.0

[0128] From Table 1, it can be seen that:

[0129] (1) The ternary positive electrode material prepared using the ternary precursor coated with titanium and aluminum in sequence provided in Examples 1-3 exhibits high rate performance and strong cycle stability;

[0130] (2) Through the comparison of Example 3 and Examples 4 and 5, it can be known that in the application, the ternary precursor core has a higher porosity, so that the ternary cathode material prepared from the ternary precursor has a large number of connected pores inside, which can shorten the diffusion distance of lithium ions, enhance the contact between the electrolyte and the inside of the ternary cathode material, accelerate the transmission of lithium ions, and significantly improve the rate performance of the battery; in addition, the pores of the ternary cathode material can act as a buffer space to relieve the volume expansion stress during charging and discharging, reduce particle cracking, and improve the cycle stability;

[0131] (3) Through the comparison of Example 3 and Examples 6 and 7, it can be known that in the application, the ratio of the molar amount of TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer will affect the performance of the battery; when the ratio of the molar amount of TiO2·xH2O in the titanium oxide intermediate layer to the molar amount of Al(OH)3 in the Al(OH)3 outer layer is 1:(0.2-1), the battery has higher rate performance and cycle stability, which is because the titanium-aluminum molar ratio of 1:(0.2-1) can balance ion transmission and structural stability: the appropriate Al2O3 outer layer (formed after the Al(OH)3 outer layer is dehydrated) can inhibit lattice distortion, and TiO2·xH2O can maintain the smoothness of the lithium ion channel, both of which cooperatively reduce the interface impedance;

[0132] (4) Through the comparison of Example 3 and Examples 8 and 9, it can be known that in the application, the value of the pH of the reaction solution adjusted in step (2) of the preparation method of the ternary precursor will affect the performance of the battery; when the pH of the reaction solution is adjusted to 3-4, the battery has higher rate performance and cycle stability, which is because when the pH is 3-4, the hydrolysis rate of Ti 4+ is moderate, forming a dense titanium oxide intermediate layer rich in -OH, laying a foundation for uniform coating of the Al(OH)3 outer layer in the subsequent step, and optimizing the surface chemical stability;

[0133] (5)Through the comparison of Example 3 and Comparative Examples 1-3, it can be seen that, in the present application, the ternary precursor core is coated with a titanium oxide intermediate layer and an Al(OH)3 outer layer to obtain a ternary precursor coated with titanium and aluminum in turn. When the ternary positive electrode material is prepared from the ternary precursor, calcination is required, and the Al(OH)3 outer layer will hydrolyze to form an Al2O3 outer layer. The titanium oxide intermediate layer and the Al2O3 outer layer can inhibit the volume expansion and shrinkage of the inner core of the ternary positive electrode material, thereby improving the structural stability of the ternary positive electrode material. In addition, due to the coating of the titanium oxide intermediate layer and the Al2O3 outer layer, the inner core of the ternary positive electrode material is isolated from the electrolyte. This improves the interface performance and inhibits dissolution and delithiation, while also inhibiting the surface side reactions of the ternary positive electrode material. In addition, through the sequential coating of the titanium oxide intermediate layer and the Al2O3 outer layer, a continuous defect-free dense layer formed by the single coating of the titanium oxide intermediate layer and the Al2O3 outer layer can be avoided, thereby facilitating lithium ion diffusion. Therefore, the ternary precursor and the ternary positive electrode material prepared therefrom have high structural stability and surface chemical stability, and also have good lithium ion diffusion performance. The battery prepared from the ternary positive electrode material exhibits good rate performance and cycle stability.

[0134] The above merely describes specific embodiments of the present application, but the protection scope of the present application is not limited thereto. It should be understood by those skilled in the art that any changes or replacements within the technical scope disclosed by the present application are easily conceived and fall within the protection scope and disclosure scope of the present application.

Claims

1. A titanium-aluminum sequentially coated ternary precursor, characterized in that, The ternary precursor comprises a ternary precursor core, and an intermediate layer of titanium oxide and an outer layer of Al(OH)3 are sequentially coated on the ternary precursor core.

2. The ternary precursor of claim 1, wherein, The porosity of the ternary precursor core is 10% to 20%.

3. The ternary precursor according to claim 1 or 2, wherein The D50 particle size of the ternary precursor core is 2.5 μm to 4 μm. Preferably, the thickness of the intermediate layer of titanium oxide is 5 nm to 20 nm. Preferably, the thickness of the outer layer of Al(OH)3 is 5 nm to 20 nm. Preferably, the titanium oxide in the intermediate layer of titanium oxide comprises amorphous TiO2·xH2O, wherein x is 0.5 to 2; and the ratio of the molar amount of TiO2·xH2O in the intermediate layer of titanium oxide to the molar amount of Al(OH)3 in the outer layer of Al(OH)3 is 1:(0.2 to 1).

4. A method of preparing the ternary precursor according to any one of claims 1 to 3, characterized in that, The preparation method comprises: (1) performing a first co-precipitation reaction in a reaction solution to obtain a solution containing ternary precursor cores; (2) performing mother liquor replacement on the solution containing ternary precursor cores obtained in step (1), adjusting the pH of the reaction solution, and adding a titanium salt solution to perform a second co-precipitation reaction to obtain a solution containing precipitates; (3) adjusting the pH of the solution containing precipitates obtained in step (2) and adding an aluminum salt solution to perform a second co-precipitation reaction to obtain a ternary precursor.

5. The preparation method according to claim 4, characterized in that, In the first co-precipitation reaction of step (1), the nickel-cobalt-manganese mixed salt solution, the precipitant solution and the complexing agent solution are added into the reaction bottom solution in parallel flow to form a reaction solution; Preferably, in the first co-precipitation reaction of step (1), the temperature of the reaction solution is controlled to be 40°C to 60°C, the concentration of the complexing agent is controlled to be 4 g / L to 8 g / L, and the pH is controlled to be 10.0 to 12.0; Preferably, in the first co-precipitation reaction of step (1), a gas is introduced into the reaction solution to form micro-bubbles in the reaction solution; Preferably, by controlling the flow rate of the gas introduced, the average diameter of the micro-bubbles is controlled to be 10 μm to 100 μm; Preferably, the flow rate of the gas introduced is controlled to be 0.5 L / min to 2 L / min; Preferably, the gas comprises nitrogen and / or an inert gas.

6. The preparation method according to claim 4, characterized in that, The mother liquor replacement comprises: performing water addition and clarification on the solution containing ternary precursor cores obtained in step (1) to obtain the reaction solution of step (2); Preferably, in step (2), the pH of the reaction solution is adjusted to be 3 to 4; Preferably, in step (2), the concentration of the titanium salt in the titanium salt solution is 0.05 mol / L to 0.2 mol / L; Preferably, in step (2), the flow rate of the titanium salt solution added into the reaction solution is 6 mL / h to 18 mL / h; Preferably, in step (2), the titanium salt in the titanium salt solution comprises Ti(SO4)2 and / or TiOSO4.

7. The preparation method according to claim 4, characterized in that, In step (3), the pH of the solution containing precipitates obtained in step (2) is adjusted to be 8.5 to 9.5; Preferably, in step (3), the concentration of the aluminum salt solution is 0.02 mol / L to 0.1 mol / L; Preferably, in step (3), the flow rate of the aluminum salt solution added is 3 mL / h to 9 mL / h; Preferably, the aluminum salt in the aluminum salt solution in step (3) comprises NaAlO2 and / or Al2(SO4)3.

8. The preparation method according to claim 4, characterized in that, The preparation method comprises: (1) adding a nickel-cobalt-manganese mixed salt solution with a total concentration of metal ions of 80 g / L to 120 g / L, a precipitant solution with a mass concentration of 28 wt% to 32 wt%, and a complexing agent solution with a mass concentration of 10 wt% to 20 wt% into a reaction bottom solution with a temperature of 40°C to 60°C, a complexing agent concentration of 4 g / L to 8 g / L, and a pH of 10.0 to 12.0 in a flow manner to form a reaction solution, controlling the temperature of the reaction solution to be 40°C to 60°C, the complexing agent concentration to be 4 g / L to 8 g / L, and the pH to be 10.0 to 12.0, and stirring at a rotation speed of 200 r / min to 400 r / min to perform a first co-precipitation reaction in the reaction solution to obtain a solution containing ternary precursor nuclei; During the first co-precipitation reaction, nitrogen and / or inert gas is introduced into the reaction solution at a flow rate of 0.5 L / min to 2 L / min to form micro-bubbles with an average diameter size of 10 μm to 100 μm in the reaction solution; (2) washing the solution containing ternary precursor nuclei obtained in step (1) with water to obtain a reaction solution, adjusting the pH of the reaction solution to be 3 to 4, adding a titanium salt solution with a concentration of 0.05 mol / L to 0.2 mol / L at a flow rate of 6 mL / h to 18 mL / h, and stirring at a rotation speed of 200 r / min to 400 r / min to perform a second co-precipitation reaction to obtain a solution containing precipitates; (3) adjusting the pH of the solution containing precipitates obtained in step (2) to be 8.5 to 9.5, adding an aluminum salt solution with a concentration of 0.02 mol / L to 0.1 mol / L at a flow rate of 3 mL / h to 9 mL / h, and stirring at a rotation speed of 150 r / min to 250 r / min to perform a third co-precipitation reaction, then sequentially performing centrifugation and washing, and drying the obtained solid at a temperature of 100°C to 150°C to obtain a ternary precursor.

9. A ternary cathode material, characterized in that, The ternary positive electrode material is prepared from raw materials comprising the ternary precursor of any one of claims 1 to 3.

10. A battery, characterized by The battery comprises the ternary positive electrode material of claim 9.

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