CN112607790A - Preparation method of lithium-ion conductor-coated lithium-rich manganese-based positive electrode material - Google Patents
Preparation method of lithium-ion conductor-coated lithium-rich manganese-based positive electrode material Download PDFInfo
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Abstract
The invention discloses a preparation method of a lithium-rich manganese-based positive electrode material coated by a lithium ion conductor, which comprises the following steps of mixing a carbonate precursor and lithium carbonate according to the weight ratio of 1: dispersing the powder in absolute ethyl alcohol according to the molar ratio of 1.02-1.5, uniformly stirring and mixing, drying to obtain powder, placing the obtained powder in a muffle furnace, and performing heat preservation twice to obtain a lithium-rich manganese-based positive electrode material; dissolving zirconyl nitrate and lithium nitrate in 40-80 mL of absolute ethyl alcohol, adding urea, stirring until the zirconyl nitrate and the lithium nitrate are completely dissolved, adding a lithium-rich manganese-based positive electrode material, continuously stirring until the materials are uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven at 120-150 ℃, keeping the temperature for 15-20 hours, cooling to room temperature, carrying out vacuum filtration, washing, drying at 80 ℃ for 12 hours, collecting material powder, placing the material powder in a muffle furnace, heating to 500 ℃, keeping the temperature for 3-6 hours, and cooling to room temperature along with the furnace to obtain the lithium zirconate coated lithium-rich manganese positive electrode material.
Description
Technical Field
The invention belongs to the technical field of energy storage material design, and particularly relates to a preparation method of a lithium-ion conductor coated lithium-rich manganese-based positive electrode material.
Background
The capacity of the currently commercialized anode material is low, the requirement of a new energy electric automobile cannot be met, and the development of a high-performance anode material is the key for improving the performance of a lithium ion battery and promoting the development of the new energy electric automobile. The layered lithium-rich manganese-based oxide has high capacity (more than 250 mAh/g), low cost and good safety, and is taken as a main material of a next-generation power battery. However, there are many difficulties in the commercial application of such high performance materials: large initial irreversible capacity, poor cycle stability and high rate performance, and the like. Therefore, a series of modification works are carried out by researchers aiming at the characteristics and the defects of the lithium-rich manganese-based positive electrode material. The surface coating can protect oxygen vacancy in the first charging process and improve the first discharge capacity; effectively inhibit the side reaction of the material surface and the electrolyte, reduce the consumption of lithium ions and the dissolution of transition metal ions, and improve the cycle performance. Wherein the lithium ion conductor material Li2ZrO3The coating can relieve the corrosion of the active electrode material by the electrolyte, and a lithium ion channel is independently constructed, so that the charge exchange of the electrode interface is accelerated, and the electrochemical performance of the electrode material is improved.
Disclosure of Invention
The invention aims to provide a preparation method of a lithium-rich manganese-based positive electrode material coated by a lithium ion conductor, which can form a coating layer with uniform thickness, thereby improving the cycle performance and the rate capability of a lithium ion battery and inhibiting the voltage attenuation of the lithium ion battery.
In order to achieve the purpose, the invention discloses the following technical contents:
a preparation method of a lithium-ion conductor coated lithium-rich manganese-based positive electrode material comprises the following steps:
(1) preparing a lithium-rich manganese-based positive electrode material:
mixing a carbonate precursor and lithium carbonate according to the proportion of 1: dispersing the mixture in absolute ethyl alcohol according to a molar ratio of 1.02-1.5, wherein the addition amount of the absolute ethyl alcohol is larger than that of the absolute ethyl alcohol, uniformly stirring and mixing the mixture, drying the mixture to obtain powder, placing the obtained powder in a muffle furnace, preserving the heat at 450 ℃ for 6-12 hours, cooling the powder to room temperature, preserving the heat at 850 ℃ for 12-24 hours, and naturally cooling the powder to the room temperature to obtain the lithium-rich manganese-based positive electrode material;
(2) preparing a lithium zirconate coated lithium-rich manganese-based positive electrode material:
dissolving zirconyl nitrate and lithium nitrate in 40-80 mL of absolute ethyl alcohol, wherein the molar ratio of zirconyl nitrate to lithium nitrate is 2:1, adding urea, stirring until the zirconyl nitrate and the lithium nitrate are completely dissolved, wherein the mass ratio of zirconyl nitrate to urea is 1: 2-2.5, adding the lithium-rich manganese-based positive electrode material prepared in the step 1, continuously stirring until the mixture is uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven to 120-150 ℃, keeping the temperature for 15-20 hours, cooling to room temperature, carrying out vacuum filtration and washing to obtain powder, drying the powder on a filter membrane in the oven at 80 ℃ for 12 hours, collecting the material powder, placing the material powder in a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, keeping the temperature for 3-6 hours, and cooling to room temperature along with the furnace to obtain the lithium zirconate coated lithium-rich manganese positive electrode material.
The technical solution adopted by the invention is also characterized in that,
the carbonate precursor in the step (1) is Mn0.667Ni0.166Co0.166CO3。
The stirring time in step (1) was 3 hours, and then the solution was dried at 80 ℃ for 5 hours.
In the step (1), the temperature is increased to 450 ℃ at the heating rate of 3-5 ℃/min, and the temperature is increased to 850 ℃ at the heating rate of 3-5 ℃/min.
And (3) stirring for 2 hours after the urea is added in the step (2), and stirring for 1 hour after the lithium-rich manganese-based positive electrode material is added.
And (3) reducing the temperature to room temperature in the step (2), carrying out vacuum filtration, and washing for 3-5 times by using absolute ethyl alcohol.
The invention further discloses application of the lithium ion conductor-coated lithium-rich manganese-based positive electrode material prepared by the method in improving the cycle performance and the rate performance of the lithium ion battery and inhibiting the voltage attenuation of the lithium ion battery. The experimental results show that: by the method, a uniform coating layer is successfully formed on the surface of the lithium-rich manganese-based positive electrode material, and the cycle performance and the rate performance of the coating material are obviously improved compared with those of an uncoated material.
The invention is described in more detail below:
a preparation method of a lithium-ion conductor-coated lithium-rich manganese-based positive electrode material specifically comprises the following steps:
step 1: preparing a lithium-rich manganese-based positive electrode material;
adding a carbonate precursor Mn0.667Ni0.166Co0.166CO3And lithium carbonate as 1: dispersing the powder in absolute ethyl alcohol according to a molar ratio of 1.02-1.5, stirring for 3 hours, uniformly mixing, drying the obtained solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, keeping the temperature at 450 ℃ for 6-12 hours at a heating rate of 3-5 ℃/min, cooling to room temperature, raising the temperature to 850 ℃ at a heating rate of 3-5 ℃/min, keeping the temperature for 12-24 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based cathode material.
Step 2: preparing a lithium zirconate coated lithium-rich manganese-based positive electrode material:
zirconium oxynitrate (ZrO (NO)3)2) And dissolving lithium nitrate in anhydrous ethanol of 40-80 mL according to a molar ratio of 2:1, adding urea (the mass ratio of zirconyl nitrate to urea is 1: 2-2.5), stirring at a constant speed for 2 hours, completely dissolving, adding the lithium-rich manganese-based positive electrode material prepared in the step 1, continuously stirring for 1 hour until the mixture is uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven to 120-150 ℃, keeping the temperature for 15-20 hours, cooling to room temperature, performing vacuum filtration, washing with anhydrous ethanol for 3-5 times, drying the powder on the filter membrane in the oven at 80 ℃ for 12 hours, collecting the material powder, placing the material powder in a muffle furnace, heating to 500 ℃ at a heating rate of 3-5 ℃/min, keeping the temperature for 3-6 hours, and cooling to room temperature along with the furnace to obtain the lithium zirconate coated lithium-rich manganese positive electrode material.
The lithium-rich manganese-based anode material is prepared by a simple high-temperature solid phase method, and compared with a sol-gel method or a coprecipitation method, the method is easier to realize industrial production. The surface coating can effectively inhibit the side reaction between the material surface and the electrolyte, reduce the lithium ion consumption and the dissolution of transition metal ions, and the invention coats the lithium ion conductor Li on the surface2ZrO3Electrochemical method for improving lithium-rich manganese-based positive electrode materialChemical properties.
The invention mainly solves the problems of poor cycle stability, poor high rate performance, voltage attenuation and the like of the lithium-rich manganese-based positive electrode material, and mainly inspects the Li ion conductor2ZrO3The main difficulty of the function of the lithium-rich manganese material in the circulating process is how to successfully apply Li2ZrO3Coating the surface of the lithium-rich manganese-based positive electrode material.
Comparative experiment:
the data show that the preparation method has better effect and better performance compared with other methods.
Compared with the prior art, the preparation method of the lithium-rich manganese-based cathode material coated by the lithium ion conductor has the positive effects that: the synthetic raw materials are easy to obtain, nontoxic and low in cost, and special protection is not needed in the production process; the synthesis method has the advantages of simple process, high production efficiency and the like. Compared with the uncoated material, the lithium zirconate coated lithium-rich manganese-based cathode material prepared by the method has the advantages that the cycle performance and the rate performance are obviously improved, and meanwhile, the lithium zirconate coated lithium-rich manganese-based cathode material has an obvious effect on inhibiting voltage attenuation. Has important significance for realizing large-scale commercial use of the lithium-rich manganese-based cathode material.
Drawings
FIG. 1 is a graph showing the comparison of specific discharge capacity cycles of a coated lithium-rich manganese-based positive electrode material and an uncoated lithium-rich manganese-based positive electrode material at a current density of 0.2C (50 mA/g);
fig. 2 is a comparison graph of specific discharge capacity cycles of the coated lithium-rich manganese-based positive electrode material and the uncoated lithium-rich manganese-based positive electrode material at different multiplying powers.
Detailed Description
The invention is described below by means of specific embodiments. Unless otherwise specified, the technical means used in the present invention are well known to those skilled in the art. In addition, the embodiments should be understood as illustrative, not asThe scope of the present invention is limited only by the changes or modifications made to the material components and amounts in these embodiments, which also fall within the scope of the present invention. The raw materials and reagents used in the present invention are commercially available, wherein Mn is present0.667Ni0.166Co0.166CO3Yuan Xiangtan university (commercially available).
Example 1
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate in a molar ratio of 1: dispersing the mixture in 10mL of absolute ethyl alcohol according to the proportion of 1.1, stirring for 3 hours, and uniformly mixing. And then drying the solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, preserving the heat at 450 ℃ for 10 hours at the heating rate of 3-5 ℃/min, cooling to room temperature, then raising the temperature to 850 ℃ at the heating rate of 3-5 ℃/min, preserving the heat for 16 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material with the chemical formula of Li1.2Mn0.54Ni0.13Co0.13O2。
Weighing zirconyl nitrate (ZrO (NO)3)2) 1.52mg, dissolving zirconyl nitrate and lithium nitrate in absolute ethyl alcohol of 40mL according to the molar ratio of 2:1, adding 2.01mg of urea, stirring at constant speed for 2 hours, adding 200mg of the prepared lithium-rich manganese-based positive electrode material after complete dissolution, and continuing stirring for 1 hour until the mixture is uniform. The mixed solution was sealed in polytetrafluoroethylene and heated to 150 ℃ in an oven for 15 hours. And (3) cooling to room temperature, carrying out vacuum filtration, washing with absolute ethyl alcohol for 3-5 times, and drying the powder on the filter membrane in an oven at 80 ℃ for 12 hours. And (3) collecting material powder, putting the material powder into a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 3 hours, cooling along with the furnace to room temperature, and thus obtaining the lithium zirconate coated lithium-rich manganese cathode material.
Example 2
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate in a molar ratio of 1: dispersing the mixture in 10mL of absolute ethyl alcohol according to the proportion of 1.05, stirring the mixture for 3 hours, and uniformly mixing the mixture. Then drying the solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, keeping the temperature at 450 ℃ for 6 hours at the heating rate of 3-5 ℃/min, cooling to room temperature, and then cooling at 3-5 ℃/minRaising the temperature to 850 ℃ at the heating rate, preserving the heat for 12 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material with the chemical formula of Li1.2Mn0.54Ni0.13Co0.13O2。
Weighing 3.05mg of zirconyl nitrate, dissolving zirconyl nitrate and lithium nitrate in 40mL of absolute ethyl alcohol according to a molar ratio of 2:1, adding 4.04mg of urea, stirring at a constant speed for 2 hours, adding 200mg of the prepared lithium-rich manganese-based positive electrode material after complete dissolution, and continuously stirring for 1 hour until the mixture is uniform. The mixed solution was sealed in polytetrafluoroethylene and heated to 150 ℃ in an oven for 15 hours. And (3) cooling to room temperature, carrying out vacuum filtration, washing with absolute ethyl alcohol for 3-5 times, and drying the powder on the filter membrane in an oven at 80 ℃ for 12 hours. And (3) collecting material powder, putting the material powder into a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 3 hours, cooling along with the furnace to room temperature, and thus obtaining the lithium zirconate coated lithium-rich manganese cathode material.
Example 3
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate in a molar ratio of 1: dispersing the mixture in 10mL of absolute ethyl alcohol according to the proportion of 1.15, stirring the mixture for 3 hours, and uniformly mixing the mixture. And then drying the solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, preserving heat at 450 ℃ for 7 hours at a heating rate of 3-5 ℃/min, cooling to room temperature, then raising the temperature to 850 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 13 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material with the chemical formula of Li1.2Mn0.54Ni0.13Co0.13O2。
Weighing 4.60mg of zirconyl nitrate, dissolving zirconyl nitrate and lithium nitrate in 40mL of absolute ethyl alcohol according to a molar ratio of 2:1, adding 6.1mg of urea, stirring at a constant speed for 2 hours, adding 200mg of the prepared lithium-rich manganese-based positive electrode material after complete dissolution, and continuing stirring for 1 hour until the mixture is uniform. The mixed solution was sealed in polytetrafluoroethylene and heated to 150 ℃ in an oven for 15 hours. And (3) cooling to room temperature, carrying out vacuum filtration, washing with absolute ethyl alcohol for 3-5 times, and drying the powder on the filter membrane in an oven at 80 ℃ for 12 hours. And (3) collecting material powder, putting the material powder into a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 4 hours, cooling along with the furnace to room temperature, and thus obtaining the lithium zirconate coated lithium-rich manganese cathode material.
Example 4
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate were dispersed in anhydrous ethanol (without passing through the powder) in a molar ratio of 1:1.05, stirred for 3 hours, and mixed uniformly. And then drying the solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, preserving heat at 450 ℃ for 6 hours at a heating rate of 3-5 ℃/min, cooling to room temperature, then raising the temperature to 850 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 12 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material with the chemical formula of Li1.2Mn0.54Ni0.13Co0.13O2。
Weighing 9.34mg of zirconyl nitrate, dissolving zirconyl nitrate and lithium nitrate in 40mL of absolute ethyl alcohol according to a molar ratio of 2:1, adding 12.37mg of urea, stirring at a constant speed for 2 hours, adding 200mg of the prepared lithium-rich manganese-based positive electrode material after complete dissolution, and continuing stirring for 1 hour until the mixture is uniform. The mixed solution was sealed in polytetrafluoroethylene and heated to 150 ℃ in an oven for 15 hours. And (3) cooling to room temperature, carrying out vacuum filtration, washing with absolute ethyl alcohol for 3-5 times, and drying the powder on the filter membrane in an oven at 80 ℃ for 12 hours. And (3) collecting material powder, putting the material powder into a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving heat for 3 hours, cooling along with the furnace to room temperature, and thus obtaining the lithium zirconate coated lithium-rich manganese-based cathode material.
Example 5
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate according to a molar ratio of 1: 1.02 dispersing in absolute ethyl alcohol, stirring for 3 hours until the addition amount of the absolute ethyl alcohol is less than that of the powder, uniformly mixing, drying the obtained solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, keeping the temperature at 450 ℃ for 8 hours at the heating rate of 3-5 ℃/min, cooling to room temperature, then increasing the temperature to 850 ℃ at the heating rate of 3-5 ℃/min, keeping the temperature for 24 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material Li1.2Mn0.54Ni0.13Co0.13O2。
Zirconium oxynitrate (ZrO (NO)3)2) Weighing lithium nitrate according to the molar ratio of 2:1, dissolving the lithium nitrate in 50mL of absolute ethyl alcohol, adding 8.082mg of urea, stirring at constant speed for 2 hours, and adding the Li prepared in the step 1 after the lithium nitrate is completely dissolved1.2Mn0.54Ni0.13Co0.13O2. And continuously stirring for 1 hour till the mixture is uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven to 120 ℃, keeping the temperature for 18 hours, cooling to room temperature, carrying out vacuum filtration, washing for 3-5 times by using absolute ethyl alcohol, drying the powder on the filter membrane in the oven at 80 ℃ for 12 hours, collecting the material powder, putting the material powder into a muffle furnace, heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving the heat for 5 hours, and cooling to room temperature along with the furnace to obtain the lithium zirconate coated lithium-rich manganese anode material.
Example 6
Adding Mn0.667Ni0.166Co0.166CO3And lithium carbonate according to a molar ratio of 1: 1.5 dispersing in absolute ethyl alcohol, stirring for 3 hours until the addition amount of the absolute ethyl alcohol is less than that of the powder, uniformly mixing, drying the obtained solution at 80 ℃ for 5 hours to obtain powder, placing the powder in a muffle furnace, keeping the temperature at 450 ℃ for 12 hours at the heating rate of 3-5 ℃/min, cooling to room temperature, then increasing the temperature to 850 ℃ at the heating rate of 3-5 ℃/min, keeping the temperature for 20 hours, and naturally cooling to room temperature to obtain the lithium-rich manganese-based positive electrode material Li1.2Mn0.54Ni0.13Co0.13O2。
Step 2: preparation of lithium zirconate coated lithium-rich manganese-based positive electrode material
Zirconium oxynitrate (ZrO (NO)3)2) Weighing lithium nitrate according to the mol ratio of 2:1, dissolving the lithium nitrate in 80mL of absolute ethyl alcohol, adding 16.33mg of urea, stirring at a constant speed for 2 hours, and adding the Li prepared in the step 1 after the lithium nitrate is completely dissolved1.2Mn0.54Ni0.13Co0.13O2Continuously stirring for 1 hour till the mixture is uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven to 135 ℃, keeping the temperature for 20 hours, carrying out vacuum filtration after cooling to room temperature, washing the mixed solution for 3-5 times by using absolute ethyl alcohol, drying the powder on the filter membrane in the oven at 80 ℃ for 12 hours, collecting material powder, and putting the material powder into a muffle furnaceAnd heating to 500 ℃ at the heating rate of 3-5 ℃/min, preserving the heat for 6 hours, cooling to room temperature along with the furnace, and obtaining the lithium zirconate coated lithium-rich manganese cathode material.
The lithium zirconate coated lithium-rich manganese-based positive electrode material prepared in the above examples 2 and 4, carbon black and PVDF were uniformly mixed in a mass ratio of 8:1:1 to prepare a slurry, the slurry was uniformly coated on an aluminum foil, cut into a disc with a diameter of 12mm, a lithium metal foil was used as a negative electrode, a 1M LiPF6 EC: DMC: EMC (volume ratio of 1:1: 1) solution was used as an electrolyte, and an LIR2032 type coin cell was assembled in a glove box filled with argon gas. As a comparative example, a LIR2032 type coin cell was assembled under the same conditions using a non-coated lithium-rich manganese-based positive electrode material. And (3) carrying out charge-discharge cycle test on the battery at room temperature, wherein the test conditions are the same, and the voltage interval is 2-4.8V. As shown in fig. 1, which is a graph comparing the discharge specific capacity cycles of the coated lithium-rich manganese-based positive electrode material and the uncoated lithium-rich manganese-based positive electrode material at a current density of 0.2C (50 mA/g), it can be known from the test results of fig. 1 that: compared with the uncoated lithium-rich manganese base (221.5 mAh/g), the discharge capacity of the embodiment 2 under the current density of 50mA/g can reach 257mAh/g, and the capacity retention rate of 100 circles is 93.8%; in example 4, the discharge capacity is 233mAh/g, and the capacity retention rate at 100 cycles is 81%; as shown in fig. 2, it is a comparison graph of specific discharge capacity cycles of the coated lithium-rich manganese-based positive electrode material and the uncoated lithium-rich manganese-based positive electrode material under different multiplying factors. In the rate performance test, the cycle was performed at 0.2C, 0.5C, 1C, 1.5C, 2C, and 0.2C, respectively, every 10 cycles. As can be seen from fig. 2: example 2 has better rate capability, especially under the current density of 500mA/g, the discharge capacity can reach 160 mAh/g. Therefore, the cycle performance and rate capability of the lithium-rich manganese-based cathode material can be obviously improved by coating the lithium ion conductor. The improvement effect achieved by different coating amounts is different.
Claims (6)
1. A preparation method of a lithium-ion conductor coated lithium-rich manganese-based positive electrode material is characterized by comprising the following steps:
(1) preparing a lithium-rich manganese-based positive electrode material:
mixing a carbonate precursor and lithium carbonate according to the proportion of 1:dispersing the mixture in absolute ethyl alcohol according to a molar ratio of 1.02-1.5, wherein the addition amount of the absolute ethyl alcohol is larger than that of the absolute ethyl alcohol, uniformly stirring and mixing the mixture, drying the mixture to obtain powder, placing the obtained powder in a muffle furnace, preserving the heat at 450 ℃ for 6-12 hours, cooling the powder to room temperature, preserving the heat at 850 ℃ for 12-24 hours, and naturally cooling the powder to the room temperature to obtain the lithium-rich manganese-based positive electrode material; the carbonate precursor is Mn0.667Ni0.166Co0.166CO3；
(2) Preparing a lithium zirconate coated lithium-rich manganese-based positive electrode material:
dissolving zirconyl nitrate and lithium nitrate in 40-80 mL of absolute ethyl alcohol, wherein the molar ratio of zirconyl nitrate to lithium nitrate is 2:1, adding urea, stirring until the zirconyl nitrate and the lithium nitrate are completely dissolved, wherein the mass ratio of zirconyl nitrate to urea is 1: 2-2.5, adding the lithium-rich manganese-based positive electrode material prepared in the step (1), continuously stirring until the mixture is uniform, sealing the obtained mixed solution in polytetrafluoroethylene, heating the mixed solution in an oven to 120-150 ℃, keeping the temperature for 15-20 hours, cooling to room temperature, carrying out vacuum filtration and washing to obtain powder, drying the powder on a filter membrane in the oven at 80 ℃ for 12 hours, collecting the material powder, placing the material powder in a muffle furnace, heating to 500 ℃ at a heating rate of 3-5 ℃/min, keeping the temperature for 3-6 hours, and cooling to room temperature along with the furnace to obtain the lithium zirconate coated lithium-rich manganese positive electrode material.
2. The method according to claim 1, wherein the stirring time in the step (1) is 3 hours, and then the solution is dried at 80 ℃ for 5 hours.
3. The method according to claim 1, wherein the temperature in the step (1) is raised to 450 ℃ at a temperature raising rate of 3 to 5 ℃/min, and is raised to 850 ℃ at a temperature raising rate of 3 to 5 ℃/min.
4. The production method according to claim 1, wherein the stirring time after the urea is added in the step (2) is 2 hours, and the stirring time after the lithium-rich manganese-based positive electrode material is added is 1 hour.
5. The preparation method of claim 1, wherein the temperature in the step (2) is reduced to room temperature, then vacuum filtration is carried out, and the product is washed for 3-5 times by using absolute ethyl alcohol.
6. The lithium ion conductor-coated lithium-rich manganese-based positive electrode material prepared by the method of claim 1 is applied to the aspects of improving the cycle performance and rate capability of a lithium ion battery and inhibiting the voltage attenuation of the lithium ion battery.
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