Boron-containing molecule modified lithium nickel cobalt manganese oxide positive material and preparation method thereof

Abstract

The invention discloses a boron-containing molecule modified lithium nickel cobalt manganese oxide positive material and a preparation method thereof. A 4-vinylphenylboronic acid layer can linked on the surface of a lithium nickel cobalt manganese oxide positive material through a covalent bond manner; and a monolayer of a boron-containing group molecular layer can be formed on the surface of a lithium nickel cobalt manganese oxide powder, which has no influence on the particle size of the material. The preparation method is convenient in operation and implement, low in required modification temperature and short in time consumption during preparation, and suitable for industrial production; The prepared positive material can have obvious enhancement by applying electrochemical cycle performance of a prepared lithium ion battery, and capacity retention rates and rate performance can be obviously improved.

Description

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a boron-containing molecularly modified nickel-cobalt lithium manganese oxide positive electrode material and a preparation method thereof. Background technique

[0002] With the increasing demand for high-capacity and high-power-density Li-ion batteries, materials with high specific capacity have aroused great interest and received increasing attention in recent years. Especially high-nickel LiNi with low cost, low toxicity and high reversible capacity 1-x-y co x mn y o 2 Cathode material (abbreviated as NCM) is considered to be the best substitute for lithium cobalt oxide, the cathode material of traditional lithium-ion batteries.

[0003] High Nickel LiNi 1-x-y co x mn y o 2 The material originates from LiNiO 2 , capable of utilizing 80% of the reversible lithium deintercalation in the matrix structure, and its capacity is as high as 220mAh g -1 , relative to hav...

Examples

Embodiment 1

[0024] A method for preparing a boron-containing molecule-modified nickel-cobalt-lithium manganese oxide positive electrode material, the specific steps are as follows: 3 g of nickel-cobalt lithium manganate NCM811 powder and 10 mg of 4-vinylphenylboronic acid are dissolved in an acetone solvent, and heated at 60 ° C Stir evenly until the dissolution is complete. After refluxing for 12 hours, filter out the precipitate and wash it with acetone for 3 times, then dry it at 80°C for 24 hours to obtain 4-vinylphenylboronic acid-modified LiNi0.8Co0.1Mn0.1O2 powder. A positive electrode material of nickel cobalt lithium manganate modified with boron molecules was obtained.

Embodiment 2

[0026] A method for preparing a boron-containing molecule-modified nickel-cobalt lithium manganese oxide positive electrode material, the specific steps are as follows: 3g of nickel-cobalt lithium manganate NCM811 powder and 20mg of 4-vinylphenylboronic acid are placed in an acetone solvent at 65°C Stir well, and after refluxing for 10 h, the precipitate was filtered out and washed with acetone for 3 times, and then dried at 85 °C for 26 h to obtain 4-vinylbenzeneboronic acid-modified LiNi 0.8 co 0.1 mn 0.1 o 2 Powder, the positive electrode material of nickel cobalt lithium manganate modified with boron molecules can be obtained.

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a boron-containing molecularly modified nickel-cobalt lithium manganese oxide positive electrode material and a preparation method thereof. Background technique

[0002] With the increasing demand for high-capacity and high-power-density Li-ion batteries, materials with high specific capacity have aroused great interest and received increasing attention in recent years. Especially high-nickel LiNi with low cost, low toxicity and high reversible capacity 1-x-y co x mn y o 2 Cathode material (abbreviated as NCM) is considered to be the best substitute for lithium cobalt oxide, the cathode material of traditional lithium-ion batteries.

[0003] High Nickel LiNi 1-x-y co x mn y o 2 The material originates from LiNiO 2 , capable of utilizing 80% of the reversible lithium deintercalation in the matrix structure, and its capacity is as high as 220mAh g -1 , relative to hav...

Examples

Embodiment 1

[0024] A method for preparing a boron-containing molecule-modified nickel-cobalt-lithium manganese oxide positive electrode material, the specific steps are as follows: 3 g of nickel-cobalt lithium manganate NCM811 powder and 10 mg of 4-vinylphenylboronic acid are dissolved in an acetone solvent, and heated at 60 ° C Stir evenly until the dissolution is complete. After refluxing for 12 hours, filter out the precipitate and wash it with acetone for 3 times, then dry it at 80°C for 24 hours to obtain 4-vinylphenylboronic acid-modified LiNi0.8Co0.1Mn0.1O2 powder. A positive electrode material of nickel cobalt lithium manganate modified with boron molecules was obtained.

Embodiment 2

[0026] A method for preparing a boron-containing molecule-modified nickel-cobalt lithium manganese oxide positive electrode material, the specific steps are as follows: 3g of nickel-cobalt lithium manganate NCM811 powder and 20mg of 4-vinylphenylboronic acid are placed in an acetone solvent at 65°C Stir well, and after refluxing for 10 h, the precipitate was filtered out and washed with acetone for 3 times, and then dried at 85 °C for 26 h to obtain 4-vinylbenzeneboronic acid-modified LiNi 0.8 co 0.1 mn 0.1 o 2 Powder, the positive electrode material of nickel cobalt lithium manganate modified with boron molecules can be obtained.

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