Copper-doped lithium cobalt oxide precursor, cathode material, process for its preparation and its use

Abstract

A process for producing a copper-doped lithium cobalt oxide precursor, comprising the following steps: (1) Mixing a solution of soluble cobalt copper salt, urea and a carbon source to conduct a hydrothermal reaction to obtain a mixed solution; (2) subjecting the mixed solution obtained in step (1) to solid-liquid separation, washing, and drying a resulting solid product to obtain the copper-doped lithium cobalt oxide precursor; wherein the carbon source is at least one selected from the group consisting of glucose, fructose, galactose, lactose, and maltose.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of cathode materials for lithium batteries, in particular to a copper-doped lithium cobalt oxide precursor, a cathode material, a production process and its use. BACKGROUND

[0002] Lithium cobalt oxide is an early cathode material used in commercial lithium-ion batteries. It is mainly used in the manufacture of lithium-ion batteries for mobile phones, notebooks, and other portable electronic devices. The lithium cobalt oxide cathode material features a wide voltage range, easy synthesis, and rapid charge and discharge. However, existing lithium cobalt oxide materials have a number of problems at high voltages due to their inherent structure, such as poor charge-discharge cycling and poor storage performance at high temperatures. When traditional doping and plating methods are used to modify lithium cobalt oxide materials, the improvement in the discharge capacity of lithium cobalt oxide materials is limited, which cannot meet the increasingly stringent requirements of the lithium battery industry.EP4174025A1 discloses a method for producing a positive electrode active material for a lithium secondary battery, comprising the following steps (1) to (3), and a positive electrode active material for a lithium secondary battery produced by the method.(1) preparing a mixed solution by adding at least one first fuel selected from the group consisting of urea, glycine, carbohydrazide, oxalyl dihydrazide, and hexamethylenetetramine, at least one second fuel selected from the group consisting of citric acid, oxalic acid, sucrose, glucose, and acetylacetone, and a metal raw material comprising a lithium raw material, a nickel raw material, a cobalt raw material, and a manganese raw material to water and stirring the solution, (2) heating the mixed solution to burn the mixed solution into a powder form, and (3) performing a heat treatment on the powder obtained in step (2). SUMMARY

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the present invention provides a copper-doped lithium cobalt oxide precursor, a cathode material, a manufacturing method, and the use thereof. The cathode material produced from the copper-doped lithium cobalt oxide precursor has good cycling performance and good discharge capacity.

[0004] The above-mentioned technical purpose of the present invention is achieved by the following technical solutions: The present invention provides a process for preparing a copper-doped lithium cobalt oxide precursor comprising the following steps: (1) Mixing a solution of soluble cobalt copper salt, urea and a carbon source to conduct a hydrothermal reaction to obtain a mixed solution; (2) subjecting the mixed solution obtained in step (1) to solid-liquid separation, washing, and drying the obtained solid product to obtain the copper-doped lithium cobalt oxide precursor; wherein the carbon source is at least one selected from the group consisting of glucose, fructose, galactose, lactose, and maltose.

[0005] Preferably, the total concentration of metal ions in the solution of the soluble cobalt-copper salt is 0.01-1.5 mol / L, and the molar ratio of cobalt element to copper element is 10:(0.01-2).

[0006] More preferably, the total concentration of metal ions in the solution of the soluble cobalt-copper salt is 0.05-1.0 mol / L, and the molar ratio of cobalt element to copper element is 10:(0.01-1).

[0007] Preferably, the concentration of urea is 0.1-5.0 mol / L.

[0008] More preferably, the concentration of urea is 0.2-4.0 mol / L.

[0009] Preferably, the molar amount of the carbon source is 1.5-6 times the amount of the copper element.

[0010] Preferably, the molar amount of the carbon source is 2 to 4 times the amount of the copper element.

[0011] Preferably, in step (1), the hydrothermal reaction is carried out at a temperature of 100-200°C for 1-10 hours.

[0012] More preferably, the hydrothermal reaction in step (1) is carried out at a temperature of 120-160°C for 4-8h.

[0013] Preferably, the solution of the soluble cobalt copper salt is prepared from a soluble salt, and the soluble salt is at least one selected from the group consisting of sulfate salts and chloride salts.

[0014] Preferably, in step (2), washing is carried out by washing the obtained product first with ethanol and then with water.

[0015] Preferably, the drying process in step (2) is carried out by drying the obtained product at 60-150°C for 1-10 hours.

[0016] Further preferably, the drying in step (2) is carried out by drying the obtained product at 80-120°C for 2-4 hours.

[0017] Preferably, the mixing in step (1) is carried out by adding the solution of the soluble cobalt copper salt into a hydrothermal reaction vessel with an addition amount of 3 / 5-4 / 5 of the volume of the reaction vessel and then adding urea and the carbon source into the hydrothermal reaction vessel.

[0018] During the hydrothermal reaction, the stirring speed in the hydrothermal reaction vessel is preferably 100-500 rpm.

[0019] More preferably, the stirring speed during the hydrothermal reaction in the hydrothermal reaction vessel is 100-200 rpm.

[0020] A copper-doped lithium cobalt oxide precursor prepared by the above-mentioned process.

[0021] A method for producing a cathode material, comprising the following steps: mixing the above-mentioned lithium cobalt oxide precursor and a lithium source and then calcining the resulting mixture to obtain the cathode material, wherein a method of calcining first comprises heating the resulting mixture under the protection of an inert gas at a heating rate of 3-15°C / min and a heating gradient from room temperature to a temperature of 600-900°C, then introducing an oxidizing gas instead and maintaining the temperature of 600-900°C for 10-20 h.

[0022] Preferably, the lithium source is at least one selected from the group consisting of lithium carbonate and lithium hydroxide.

[0023] More preferably, calcination is carried out by first heating the resulting mixture under the protection of an inert gas at a heating rate of 5-10°C / min and a heating gradient from room temperature to a temperature of 700-850°C, then introducing an oxidizing gas instead and holding at the temperature of 700-850°C for 12-18h, where the room temperature refers to 25°C.

[0024] Preferably, a method for producing a cathode material comprising the following steps: (1) Selecting soluble salts as raw materials according to a molar ratio of cobalt element to copper element of 10: (0.01-1) to prepare a mixed salt solution having a total metal ion concentration of 0.05-1.0 mol / L, wherein the soluble salt is at least one selected from the group consisting of sulfate salt and chloride salt; (2) adding the solution of the mixed salts in step (1) into a hydrothermal reaction vessel with an addition amount of 3 / 5-4 / 5 of the volume of the reaction vessel; (3) Addition of urea into the hydrothermal reaction vessel at a concentration of 0.2-4.0 mol / l; (4) Adding a carbon source to the hydrothermal reaction vessel in a molar amount of 2-4 times the copper element; the carbon source is at least one selected from the group consisting of glucose, fructose, galactose, lactose, and maltose; (5) Sealing the hydrothermal reaction vessel, heating and stirring the resulting mixture at a heating temperature of 120-160 °C and a stirring speed of 100-200 rpm to react for 4-8 hours; (6) after completion of the reaction, subjecting the resulting reaction mixture to solid-liquid separation, washing the obtained solid product first with ethanol, then with pure water, and then drying the washed product at 80-120°C for 2-4 hours to obtain a copper-doped lithium cobalt oxide precursor; (7) according to a molar ratio of cobalt element to lithium element of 1: (1.2-1.4), mixing the precursor material and at least one of lithium carbonate and lithium hydroxide, then heating a resulting mixture under an inert gas at a heating rate of 5-10°C / min and a heating gradient from room temperature to a temperature of 700-850°C, then introducing air or oxygen instead, maintaining the temperature for 12-18h, then pulverizing and sieving a resulting mixture, and removing iron from the mixture to obtain a cathode material of copper-doped lithium cobalt oxide.

[0025] The present invention provides a cathode material produced by the above-mentioned method.

[0026] Preferably, the discharge capacity of the cathode material is not less than 219 mAh / g, e.g., 219.4 mAh / g.

[0027] Preferably, the capacity retention rate after 600 cycles of the cathode material is not lower than 84%, e.g., 84.6%.

[0028] The present invention provides for the use of the above-mentioned cathode material in lithium-ion batteries.

[0029] The advantageous effects of the present invention are as follows.

[0030] In the present invention, a cobalt-copper mixed salt, urea, and a carbon source are subjected to a hydrothermal reaction in a reaction vessel to obtain a copper-doped lithium cobalt oxide precursor, which is then mixed with a lithium source and calcined to produce a copper-doped cathode material. Since the copper-doped lithium cobalt oxide precursor is doped with a copper element, the discharge capacity and cycle stability of the cathode material under high voltage can be further improved during the production of a cathode material, so that the discharge capacity of the cathode material is 219.4 mAh / g or more, and the capacity retention rate after 600 cycles is 84.6% or more. The reaction principle is as follows: During the hydrothermal reaction: CO(NH2)2+H2O→2NH3+CO2 NH3·H2O→NH4 + +OH - CO2+H2O→CO3 2- +2H + Co 2+ +(1-0.5y)CO3 2- +yOH - →Co(OH) y (CO3) 1-0.5y , where y<2. Copper ions are complexed with urea and reacted with a carbon source (e.g. glucose) in a redox reaction: {Cu[CO(NH2)2]4} 2+ +CH2OH(CHOH)4CHO→ CH2OH(CHOH)4COOH+Cu2O+2H2O+4CO(NH2)2 CH2OH(CHOH)4COOH+NH3 · H2O→CH2OH(CHOH)4COONH4+H2O.

[0031] During the hydrothermal reaction, the copper(II) oxide precipitate is formed by the redox reaction between copper ions and carbohydrates, and the divalent cobalt ions are precipitated in the form of basic cobalt carbonate, forming a mixed precipitate of copper(II) oxide and basic cobalt carbonate. Compared with copper(II) oxide, the required temperature for calcining copper(II) oxide and lithium source to produce lithium cuprate is lower, and lithium cuprate can be obtained in the pure phase. Therefore, copper(II) oxide is more conducive to the formation of lithium cuprate than divalent copper during the subsequent high-temperature calcination of the cathode material.

[0032] In the high-temperature calcination phase, the lithium source can be melted by heating in an inert atmosphere without causing oxidation of the copper oxide.

[0033] When air / oxygen is then added, the reactions proceed as follows: 4Co(OH) y (CO3) 1-0 . 5y +4LiOH+O2+4LiCoO2+(2+2y)H2O+(4-2y)CO2 2Cu2O+8LiOH+O2→4Li2CuO2+4H2O.

[0034] The lithium cuprate cathode material (Li2CuO2) is a lithium-rich cathode material, which has higher theoretical specific capacity and theoretical energy density than other cathode materials and can impart pre-lithiation capability to the obtained lithium cobalt oxide cathode material, which further improves the discharge capacity of the cathode material.

[0035] In addition, the structure of lithium copper hydride contains [CuO4] chains arranged in a co-topic manner, consisting of a tetrahedron formed by oxygen atoms with the Cu atom as the center. Such a structure is relatively stable under high voltage and can also form a channel for the transfer of lithium ions. During the charging and discharging process, lithium ions can enter and exit the [CuO4] structures through the gap between them, thus ensuring the stable structure and normal charging and discharging of the cathode material simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is the scanning electron microscope (SEM) image of the copper-doped lithium cobalt oxide precursor prepared in Example 1 of the present invention; Fig. Figure 2 is the SEM image of the cathode material prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0036] The present invention is described in more detail below using concrete examples. Example 1:

[0037] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:0.5, cobalt sulfate and copper sulfate were selected as raw materials to prepare a solution of mixed salts with a total concentration of metal ions of 0.5 mol / L; (2) the solution of the mixed salts in step (1) was added into a hydrothermal reaction vessel with an addition amount of 3 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 2.0 mol / L; (4) Glucose was added to the reaction vessel with three times the molar amount of the copper element; (5) The reaction vessel was sealed, then the mixture in the reaction vessel was heated and stirred at a heating temperature of 140°C and a stirring speed of 150r / min to react for 6h; (6) After completion of the reaction, the reaction mixture was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 100°C for 3 hours to obtain the copper-doped lithium cobalt oxide precursor.

[0038] A copper-doped lithium cobalt oxide precursor was prepared by the above-mentioned method, and the SEM image of the copper-doped lithium cobalt oxide precursor is shown in Fig. 1 shown.

[0039] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.3, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium hydroxide were mixed, the mixture was heated under an inert gas at a heating rate of 10 °C / min and a heating gradient from room temperature to 850 °C, then air was introduced instead, the temperature was maintained for 15 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material.

[0040] A cathode material was prepared by the above-mentioned method, and the SEM image of the cathode material is shown in Fig. 2 shown. Example 2:

[0041] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:1, cobalt chloride and copper chloride were selected as raw materials to prepare a solution of mixed salts with a total metal ion concentration of 1.0 mol / L; (2) the solution of the mixed salts in step (1) was added to a hydrothermal reaction vessel with an addition amount of 4 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 4.0 mol / L; (4) Fructose was added to the reaction vessel with a molar amount of 4 times the copper element; (5) The reaction vessel was sealed, then the mixture in the reaction vessel was heated and stirred at a heating temperature of 160 °C and a stirring speed of 200 rpm for 4 hours; (6) After completion of the reaction, the reaction mixture was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 120°C for 2 h to obtain the copper-doped lithium cobalt oxide precursor.

[0042] A copper-doped lithium cobalt oxide precursor was prepared according to the above method.

[0043] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.4, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium carbonate were mixed, the mixture was heated under an inert gas at a heating rate of 5°C / min and a heating gradient from room temperature to 850°C, then oxygen gas was introduced instead, the temperature was maintained for 12 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material.

[0044] A cathode material was prepared according to the above method. Example 3:

[0045] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:0.01, cobalt sulfate and copper sulfate were selected as raw materials to prepare a solution of mixed salts with a total concentration of metal ions of 0.05 mol / L; (2) the solution of the mixed salts in step (1) was added to a hydrothermal reaction vessel with an addition amount of 3 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 0.2 mol / L; (4) Galactose was added to the reaction vessel with a 2-fold molar amount of the copper element; (5) The reaction vessel was sealed, then the mixture in the reaction vessel was heated and stirred at a heating temperature of 120 °C and a stirring speed of 100 rpm for 8 hours; (6) After completion of the reaction, the reaction mixture was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 80°C for 4 h to obtain the copper-doped lithium cobalt oxide precursor.

[0046] A copper-doped lithium cobalt oxide precursor was prepared according to the above method.

[0047] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.2, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium carbonate were mixed, the mixture was heated under an inert gas at a heating rate of 8 °C / min and a heating gradient from room temperature to 700 °C, then oxygen gas was introduced instead, the temperature was maintained for 18 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material.

[0048] A cathode material was prepared according to the above method. Comparative Example 1: (Compared to Example 1, no carbon source was added, and the other steps and parameters were exactly the same as in Example 1)

[0049] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:0.5, cobalt sulfate and copper sulfate were selected as raw materials to prepare a solution of mixed salts with a total concentration of metal ions of 0.5 mol / L; (2) the solution of the mixed salts in step (1) was added into a hydrothermal reaction vessel with an addition amount of 3 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 2.0 mol / L; (4) The reaction vessel was sealed, then the mixture was heated and stirred at a heating temperature of 140°C and a stirring speed of 150 rpm to react for 6 hours; (5) After completion of the reaction, the reaction mixture in the reaction vessel was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 100°C for 3 h to obtain the copper-doped lithium cobalt oxide precursor.

[0050] A copper-doped lithium cobalt oxide precursor was prepared according to the above method.

[0051] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.3, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium hydroxide were mixed, the mixture was heated under an inert gas at a heating rate of 10 °C / min and a heating gradient from room temperature to 850 °C, then air was introduced instead, the temperature was maintained for 15 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material.

[0052] A cathode material was prepared according to the above method. Comparative Example 2: (Compared to Example 2, no carbon source was added, and the other steps and parameters were exactly the same as in Example 2)

[0053] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:1, cobalt chloride and copper chloride were selected as raw materials to prepare a solution of mixed salts with a total metal ion concentration of 1.0 mol / L; (2) the solution of the mixed salts in step (1) was added to a hydrothermal reaction vessel with an addition amount of 4 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 4.0 mol / L; (4) The reaction vessel was sealed, then the mixture was heated and stirred at a heating temperature of 160°C and a stirring speed of 200r / min for 4 hours; (5) After completion of the reaction, the reaction mixture in the reaction vessel was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 120°C for 2 h to obtain the copper-doped lithium cobalt oxide precursor.

[0054] A copper-doped lithium cobalt oxide precursor was prepared according to the above method.

[0055] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.4, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium carbonate were mixed, the mixture was heated under an inert gas at a heating rate of 5°C / min and a heating gradient from room temperature to 850°C, then oxygen gas was introduced instead, the temperature was maintained for 12 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material. Comparative Example 3: (Compared to Example 3, no carbon source was added, and the other steps and parameters were exactly the same as in Example 3)

[0056] A process for preparing a copper-doped lithium cobalt oxide precursor has been provided, comprising the following steps: (1) According to a molar ratio of cobalt element to copper element of 10:0.01, cobalt sulfate and copper sulfate were selected as raw materials to prepare a solution of mixed salts with a total concentration of metal ions of 0.05 mol / L; (2) the solution of the mixed salts in step (1) was added into a hydrothermal reaction vessel with an addition amount of 3 / 5 of the volume of the reaction vessel; (3) Urea was added to the reaction vessel at a concentration of 0.2 mol / L; (4) The reaction vessel was sealed, then the mixture was heated and stirred at a heating temperature of 120°C and a stirring speed of 100r / min for 8 hours; (5) After completion of the reaction, the reaction mixture in the reaction vessel was subjected to solid-liquid separation, the obtained solid product was first washed with ethanol, then with pure water, and then the washed product was dried at 80°C for 4 h to obtain the copper-doped lithium cobalt oxide precursor.

[0057] A copper-doped lithium cobalt oxide precursor was prepared according to the above method.

[0058] A method for producing a cathode material, comprising the following steps: According to a molar ratio of cobalt element to lithium element of 1:1.2, the above-mentioned copper-doped lithium cobalt oxide precursor and lithium carbonate were mixed, the mixture was heated under an inert gas at a heating rate of 8 °C / min and a heating gradient from room temperature to 700 °C, then oxygen gas was introduced instead, the temperature was maintained for 18 h, and then the resulting mixture was crushed, sieved, and freed of iron to obtain a copper-doped lithium cobalt oxide cathode material.

[0059] A cathode material was prepared according to the above method. Test example:

[0060] The cathode materials obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were used as the active materials, acetylene black was used as the conductive agent, and PVDF was used as the binder. The active materials, conductive agent, and binder were weighed in a ratio of 92:4:4 and added with a certain amount of the organic solvent NMP. The resulting mixture was stirred and coated on aluminum foil to prepare a cathode foil, and a lithium metal foil was used as the negative electrode. A CR2430 button battery was prepared in an argon gas-filled glove box. The electrical performance test was conducted in the CT2001A blue electricity test system. Test conditions: 3.0-4.48 V, current density 1C=180 mAh / g, test temperature: 25±1°C. The test results are shown in Table 1 below. Table 1: Battery electrical performance test results Discharge capacity mAh / g at 0.1C / 4.48V Capacity retention rate after 600 cycles at 0.1C / 4.48V Example 1 232,3 88,3% Example 2 248,6 84,6% Example 3 219,4 87,2% Comparative Example 1 215,2 77,2% Comparative Example 2 220,4 72,3% Comparative Example 3 209,7 79,8%

[0061] From Table 1, it can be seen that the cathode materials prepared with the copper-doped lithium cobalt oxide precursors prepared by the method of the present invention exhibited good discharge capacity and cycle stability, with a discharge capacity of 219.4 mAh / g or more and a capacity retention rate after 600 cycles of 84.6% or more. Furthermore, comparing Example 1 with Comparative Example 1, Example 2 with Comparative Example 2, and Example 3 with Comparative Example 3, it can be seen that the cycle stability and discharge capacity of the finally prepared cathode material decreased when no carbon source was added in the hydrothermal reaction during the preparation of the copper-doped lithium cobalt oxide precursor.

Claims

[1] A process for producing a copper-doped lithium cobalt oxide precursor, comprising the following steps: (1) Mixing a solution of soluble cobalt copper salt, urea and a carbon source to conduct a hydrothermal reaction to obtain a mixed solution; (2) subjecting the mixed solution obtained in step (1) to solid-liquid separation, washing, and drying a resulting solid product to obtain the copper-doped lithium cobalt oxide precursor; wherein the carbon source is at least one selected from the group consisting of glucose, fructose, galactose, lactose, and maltose. [2] A method for producing the copper-doped lithium cobalt oxide precursor according to claim 1, wherein the total concentration of metal ions in the soluble cobalt copper salt solution is 0.01-1.5 mol / L and the molar ratio of cobalt element to copper element is 10: 0.01-2. [3] A process for producing the copper-doped lithium cobalt oxide precursor according to claim 1, wherein the concentration of urea is 0.1-5.0 mol / L. [4] A method for producing the copper-doped lithium cobalt oxide precursor according to claim 2, wherein the molar amount of the carbon source is 1.5-6 times the amount of the copper element. [5] A process for producing the copper-doped lithium cobalt oxide precursor according to claim 1, wherein in step (1) the hydrothermal reaction is carried out at a temperature of 100-200°C for 1-10 h. [6] A copper-doped lithium cobalt oxide precursor prepared by the process according to any one of claims 1-5. [7] A process for producing a cathode material comprising the following steps: Mixing the lithium cobalt oxide precursor according to claim 6 and a lithium source, and then calcining the resulting mixture to obtain the cathode material; wherein a method of calcining comprises first heating the resulting mixture under the protection of an inert gas at a heating rate of 3-15°C / min and a heating gradient from room temperature to a temperature of 600-900°C, then introducing an oxidizing gas instead and maintaining the temperature of 600-900°C for 10-20 h. [8] Cathode material produced by the process according to claim 7. [9] Use of the cathode material according to claim 8 in a lithium-ion battery.

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