Preparation method of high-nickel positive electrode material of composite coating layer

Abstract

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a preparation method of a high-nickel positive electrode material of a composite coating layer. The method comprises the following steps: (1) adding the high-nickel positive electrode material and soluble aluminum salt into deionized water, and stirring; (2) adding an alkaline solution of lithium salt into the solution in the step (1), stirring, and enabling the pH value to be 8-14; (3) carrying out suction filtration and washing on the mixed solution obtained in the step (2), and drying in a drying oven; and (4) uniformly mixing the positive electrode material dried in the step (3) with a nano coating agent, then putting the mixture into a preheated box-type furnace filled with oxygen for sintering, and sieving to obtain the high-nickel positive electrode material with the composite coating layer. Compared with a pure dry coating method, the wet precipitation coating method has the advantages that the coating uniformity and an acting force on the surface of the high-nickel positive electrode material are stronger, the coating is uniform, the thickness of the coating layer is controllable, and the comprehensive electrochemical performance of the positive electrode material is improved.

Description

technical field

[0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a preparation method of a high-nickel cathode material with a composite coating layer. Background technique

[0002] With the process of economic globalization and the extensive use of fossil fuels, environmental degradation and energy shortages have gradually become increasingly concerned issues. In this case, the development of clean energy has become a hot topic of current concern. Lithium-ion batteries have become the focus of global research due to a series of advantages such as high operating voltage, long cycle life, high energy density and environmental friendliness. As an important part of the lithium-ion battery, the cathode material not only participates in the electrochemical reaction of the battery as the cathode material, but also serves as the lithium source of the entire lithium-ion battery, providing power for the entire battery system....

Examples

Embodiment 1

[0030] In a 1L beaker, add 200ml of deionized water, stirring speed 400r / min, 200g high nickel cathode material LiNi 0.80 co 0.10 mn 0.10 o 2 Add it into the beaker, after stirring evenly, slowly add 2.78g of aluminum nitrate, add 1M lithium hydroxide solution during the stirring process, adjust the pH to 9, and continue stirring for 15 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 4 hours to obtain dried materials, then ball mill and stir with 2.29g of nano-boric acid, sieve, place in a sagger, and react in a preheated box furnace at 320°C for 6 hours under an oxygen atmosphere . After cooling slowly, a positive electrode material with a uniform coating can be obtained after sieving, as shown in the SEM image figure 1 shown.

Embodiment 2

[0032] In a 1L beaker, add 240ml deionized water, stirring speed 300r / min, 200g high nickel cathode material LiNi 0.80 co 0.10 mn 0.10 o 2 Add it into the beaker, after stirring evenly, slowly add 4.17g of aluminum nitrate, add 2M lithium hydroxide solution during the stirring process, adjust the pH to 10, and continue stirring for 20 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 3 hours to obtain dried materials, then ball mill and stir with 1.15g of nano-boric acid, sieve, place in a sagger, and react in a preheated box furnace at 300°C for 8 hours in an oxygen atmosphere . Cool slowly, and after sieving, a positive electrode material with a uniform coating can be obtained, as shown in the XRD diagram figure 2 shown.

Embodiment 3

[0034] In a 1L beaker, add 160ml of deionized water, stirring speed 500r / min, 200g high nickel cathode material LiNi0.83 co 0.12 mn 0.05 o 2 Add it into the beaker, after stirring evenly, slowly add 4.17g of aluminum nitrate, add 1.5M lithium hydroxide solution during the stirring process, adjust the pH to 9, and continue stirring for 20 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 5 hours to obtain dry materials, then ball mill and stir with 0.46g of ammonium metavanadate, sieve, place in a sagger, and place in a preheated box furnace under an oxygen atmosphere at 350°C Reaction 6h. After cooling slowly, a cathode material with a uniform coating layer can be obtained after sieving.

[0035] The high-nickel positive electrode material with coating layer prepared above is cycled under the charge-discharge condition of 1C / 1C, by image 3 It can be seen from the cycle ...

technical field

[0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a preparation method of a high-nickel cathode material with a composite coating layer. Background technique

[0002] With the process of economic globalization and the extensive use of fossil fuels, environmental degradation and energy shortages have gradually become increasingly concerned issues. In this case, the development of clean energy has become a hot topic of current concern. Lithium-ion batteries have become the focus of global research due to a series of advantages such as high operating voltage, long cycle life, high energy density and environmental friendliness. As an important part of the lithium-ion battery, the cathode material not only participates in the electrochemical reaction of the battery as the cathode material, but also serves as the lithium source of the entire lithium-ion battery, providing power for the entire battery system....

Examples

Embodiment 1

[0030] In a 1L beaker, add 200ml of deionized water, stirring speed 400r / min, 200g high nickel cathode material LiNi 0.80 co 0.10 mn 0.10 o 2 Add it into the beaker, after stirring evenly, slowly add 2.78g of aluminum nitrate, add 1M lithium hydroxide solution during the stirring process, adjust the pH to 9, and continue stirring for 15 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 4 hours to obtain dried materials, then ball mill and stir with 2.29g of nano-boric acid, sieve, place in a sagger, and react in a preheated box furnace at 320°C for 6 hours under an oxygen atmosphere . After cooling slowly, a positive electrode material with a uniform coating can be obtained after sieving, as shown in the SEM image figure 1 shown.

Embodiment 2

[0032] In a 1L beaker, add 240ml deionized water, stirring speed 300r / min, 200g high nickel cathode material LiNi 0.80 co 0.10 mn 0.10 o 2 Add it into the beaker, after stirring evenly, slowly add 4.17g of aluminum nitrate, add 2M lithium hydroxide solution during the stirring process, adjust the pH to 10, and continue stirring for 20 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 3 hours to obtain dried materials, then ball mill and stir with 1.15g of nano-boric acid, sieve, place in a sagger, and react in a preheated box furnace at 300°C for 8 hours in an oxygen atmosphere . Cool slowly, and after sieving, a positive electrode material with a uniform coating can be obtained, as shown in the XRD diagram figure 2 shown.

Embodiment 3

[0034] In a 1L beaker, add 160ml of deionized water, stirring speed 500r / min, 200g high nickel cathode material LiNi0.83 co 0.12 mn 0.05 o 2 Add it into the beaker, after stirring evenly, slowly add 4.17g of aluminum nitrate, add 1.5M lithium hydroxide solution during the stirring process, adjust the pH to 9, and continue stirring for 20 minutes. The resulting mixture was filtered, vacuum filtered, rinsed with a little absolute ethanol, and dried. Dry in a vacuum drying oven at 120°C for 5 hours to obtain dry materials, then ball mill and stir with 0.46g of ammonium metavanadate, sieve, place in a sagger, and place in a preheated box furnace under an oxygen atmosphere at 350°C Reaction 6h. After cooling slowly, a cathode material with a uniform coating layer can be obtained after sieving.

[0035] The high-nickel positive electrode material with coating layer prepared above is cycled under the charge-discharge condition of 1C / 1C, by image 3 It can be seen from the cycle ...

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