Lithium titanate coated positive electrode material for power battery and preparation method

Abstract

The invention belongs to the technical field of technical lithium batteries, and provides a lithium titanate coated positive electrode material for a power battery and a preparation method. The methodcomprises the following steps: mixing a positive electrode material precursor with graphene oxide, performing heating to form a positive electrode material precursor coated with graphene oxide hydrogel, adding butyl titanate, performing reaction with a lithium source, and performing coating in a graphene oxide hydrogel grid to prepare the lithium titanate coated positive electrode material. Comparing with a material prepared through a traditional method, the prepared lithium titanate coated positive electrode material can effectively inhibit the gas expansion caused by contact between lithiumtitanate and an electrolyte because the surface of the positive electrode active material is uniformly coated with the formed graphene oxide / lithium titanate composite material. Meanwhile, the preparation process is simple, the process is easy to control, and the lithium titanate-coated positive electrode material has a good prospect in large-scale industrial production.

Description

technical field

[0001] The invention belongs to the technical field of lithium batteries, and provides a lithium titanate-coated cathode material for a power battery and a preparation method thereof. Background technique

[0002] Lithium-ion battery is a new generation of green high-energy battery with excellent performance, and has become one of the focuses of high-tech development. Lithium-ion batteries have the following characteristics: high voltage, high capacity, low consumption, no memory effect, no pollution, small size, small internal resistance, less self-discharge, and more cycles. Because of the above-mentioned characteristics, lithium-ion batteries have been applied to many civilian and military fields such as mobile phones, notebook computers, video cameras, and digital cameras.

[0003] The main constituent materials of lithium-ion batteries include electrolyte, separator materials, positive and negative electrode materials, etc. The positive electrode mater...

Examples

Embodiment 1

[0029] Nickel sulfate, cobalt sulfate, manganese sulfate are prepared according to the mixture of mol ratio 0.53:0.12:0.12, be formulated with the mixed solution that molar concentration is 1.3mol / L, then add mass concentration in 66g mixed solution and be 13% sodium hydroxide solution, Adjust the pH value to 10.5, heat and stir the reaction, the temperature of the heating and stirring reaction is 100°C, the stirring speed is 250r / min, and the stirring time is 2h to prepare the positive electrode active material precursor solution; then add 13g to the 76g precursor solution Graphene oxide, 11g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 33g hydrogel coating, 13g butyl titanate are added 51g anhydrous In ethanol, then slowly add 3g of acetylacetone dropwise, let it stand and age for 24.5h, and then evaporate to dryness of absolute ethanol to obtain the precursor...

Embodiment 2

[0034]Nickel sulfate, cobalt sulfate, manganese sulfate are formulated according to the mixture of mol ratio 0.53:0.12:0.12, are mixed with the mixed solution that molar concentration is 1.2mol / L, then add mass concentration in 62g mixed solution and be 12% sodium hydroxide solution, Adjust the pH value to 10, heat and stir the reaction, the temperature of the heating and stirring reaction is 110°C, the stirring speed is 220r / min, and the stirring time is 3h to prepare the positive electrode active material precursor solution; then add 12g to the 79g precursor solution Graphene oxide, 9g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 32g hydrogel coating, 11g butyl titanate are added 54g anhydrous In ethanol, then slowly add 3g of acetylacetone dropwise, let it stand and age for 24.5h, and then evaporate to dryness of absolute ethanol to obtain a modified positive...

Embodiment 3

[0037] Nickel sulfate, cobalt sulfate, manganese sulfate are formulated according to the mixture of mol ratio 0.54:0.14:0.14, are mixed with the mixed solution that molar concentration is 1.4mol / L, then add mass concentration in 67g mixed solution and be 14% sodium hydroxide solution, Adjust the pH value to 11, heat and stir the reaction, the temperature of the heating and stirring reaction is 100°C, the stirring speed is 260r / min, and the stirring time is 2h to prepare the positive active material precursor solution; then add 14g to the 72g precursor solution Graphene oxide, 14g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 34g hydrogel coating, 13g butyl titanate are added 49g anhydrous In ethanol, then slowly add 4g of acetylacetone dropwise, let it stand and age for 25.5h, and then evaporate to dryness of absolute ethanol to obtain the precursor of the modifi...

technical field

[0001] The invention belongs to the technical field of lithium batteries, and provides a lithium titanate-coated cathode material for a power battery and a preparation method thereof. Background technique

[0002] Lithium-ion battery is a new generation of green high-energy battery with excellent performance, and has become one of the focuses of high-tech development. Lithium-ion batteries have the following characteristics: high voltage, high capacity, low consumption, no memory effect, no pollution, small size, small internal resistance, less self-discharge, and more cycles. Because of the above-mentioned characteristics, lithium-ion batteries have been applied to many civilian and military fields such as mobile phones, notebook computers, video cameras, and digital cameras.

[0003] The main constituent materials of lithium-ion batteries include electrolyte, separator materials, positive and negative electrode materials, etc. The positive electrode mater...

Examples

Embodiment 1

[0029] Nickel sulfate, cobalt sulfate, manganese sulfate are prepared according to the mixture of mol ratio 0.53:0.12:0.12, be formulated with the mixed solution that molar concentration is 1.3mol / L, then add mass concentration in 66g mixed solution and be 13% sodium hydroxide solution, Adjust the pH value to 10.5, heat and stir the reaction, the temperature of the heating and stirring reaction is 100°C, the stirring speed is 250r / min, and the stirring time is 2h to prepare the positive electrode active material precursor solution; then add 13g to the 76g precursor solution Graphene oxide, 11g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 33g hydrogel coating, 13g butyl titanate are added 51g anhydrous In ethanol, then slowly add 3g of acetylacetone dropwise, let it stand and age for 24.5h, and then evaporate to dryness of absolute ethanol to obtain the precursor...

Embodiment 2

[0034]Nickel sulfate, cobalt sulfate, manganese sulfate are formulated according to the mixture of mol ratio 0.53:0.12:0.12, are mixed with the mixed solution that molar concentration is 1.2mol / L, then add mass concentration in 62g mixed solution and be 12% sodium hydroxide solution, Adjust the pH value to 10, heat and stir the reaction, the temperature of the heating and stirring reaction is 110°C, the stirring speed is 220r / min, and the stirring time is 3h to prepare the positive electrode active material precursor solution; then add 12g to the 79g precursor solution Graphene oxide, 9g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 32g hydrogel coating, 11g butyl titanate are added 54g anhydrous In ethanol, then slowly add 3g of acetylacetone dropwise, let it stand and age for 24.5h, and then evaporate to dryness of absolute ethanol to obtain a modified positive...

Embodiment 3

[0037] Nickel sulfate, cobalt sulfate, manganese sulfate are formulated according to the mixture of mol ratio 0.54:0.14:0.14, are mixed with the mixed solution that molar concentration is 1.4mol / L, then add mass concentration in 67g mixed solution and be 14% sodium hydroxide solution, Adjust the pH value to 11, heat and stir the reaction, the temperature of the heating and stirring reaction is 100°C, the stirring speed is 260r / min, and the stirring time is 2h to prepare the positive active material precursor solution; then add 14g to the 72g precursor solution Graphene oxide, 14g chitosan, stirring reaction, separation, obtained the positive electrode material precursor of hydrogel coating; Then the positive electrode material precursor of 34g hydrogel coating, 13g butyl titanate are added 49g anhydrous In ethanol, then slowly add 4g of acetylacetone dropwise, let it stand and age for 25.5h, and then evaporate to dryness of absolute ethanol to obtain the precursor of the modifi...

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