Method for preparing ternary anode material of long-service-life and high-capacity lithium ion battery

Abstract

A method for preparing a ternary anode material of a long-service-life and high-capacity lithium ion battery and belongs to the technical field of material synthesis. The method comprises the following steps: weighing a lithium source and NixCoyMnz(OH)2, uniformly mixing, pre-burning at a temperature of 400-600 DEG C for 2-6 h, and forging at a temperature of 700-1000 DEG C for 6-16 h; uniformly mixing the ternary anode material, the lithium source and nanometer TiO2; forging at a temperature of 700-950 DEG C for 3-8 h to obtain the ternary anode material which is prepared by twice lithium adding and twice forging. The ternary anode material is prepared through twice lithium adding and twice forging, and the extra lithium source which is introduced through twice lithium adding and twice forging is electrochemically pre-embedded in an anode. Meanwhile, the Li+ diffusion rate can be effectively increased through the doping of Ti4+, and the irreversible capacity loss is reduced. In an interval of 2.3-4.6 V, a discharging platform is prolonged, and the first discharging capacity, the cyclic performance and the rate performance of the material are obviously improved. The method is simple, effective, economical and practical and has a remarkable industrial application effect.

Description

technical field

[0001] The invention belongs to the technical field of material synthesis, and relates to a preparation method of a lithium-ion battery cathode material, in particular to a preparation method of a long-life, high-capacity lithium-ion battery ternary cathode material. Background technique

[0002] As another secondary battery after lead-acid batteries, nickel-cadmium batteries and nickel-metal hydride batteries, lithium-ion batteries have significant advantages such as no memory effect, high working voltage, and low self-discharge rate. preferred technology. In recent years, lithium-ion batteries have been widely used in the field of high-energy batteries, and gradually expanded to the field of power batteries.

[0003] In the composition of lithium-ion batteries, the cathode material determines the main performance of the battery. Lithium-ion battery ternary material LiNi 1-x-y co x mn y o 2 Due to the advantages of high gram capacity, good safety, low ...

Examples

specific Embodiment approach 1

[0027] Specific implementation mode 1: In this implementation mode, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0028] 1. Weigh nickel sulfate, cobalt sulfate, and manganese sulfate respectively in a molar ratio of 1:1:1, and dissolve them in deionized water and mix them evenly. Add 2 mol / L precipitant sodium carbonate and a certain amount of complexing agent ammonia water one by one. Add it dropwise, control the molar ratio of metal salt to ammonia water to be 1:0.75, the pH value of the reaction is between 8 and 9, react at 60°C for 12 h, and stir continuously at a speed of 600 rpm, and suction filter after the reaction. Wash repeatedly to remove impurities, dry at 80°C for 24 h, and synthesize the precursor of ternary cathode material (NiCoMn)(OH) 2 , and its D50 particle size is 8 microns.

[0029] Ternary precursors are also available commercially.

[0030] 2. Molar ratio Li:NiCoMn(OH) 2 =1.05...

specific Embodiment approach 2

[0034] Specific implementation mode 2: In this implementation mode, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0035] 1. Weigh nickel sulfate, cobalt sulfate, and manganese sulfate respectively in a molar ratio of 5:2:3, and dissolve them in deionized water and mix them uniformly. 2mol / L precipitant sodium hydroxide and a certain amount of complexing agent ammonia Add it dropwise, control the molar ratio of metal salt to ammonia water to be 1:0.75, the pH value of the reaction is between 10~11, react at 60°C for 12h, and stir continuously at a speed of 600 rpm. Wash, remove impurities, dry at 80°C for 24h, and synthesize the precursor of ternary cathode material (Ni 0.5 co0.2 mn 0.3 )(OH) 2 , and its D50 particle size is 9 microns.

[0036] Ternary precursors are also available commercially.

[0037] Two, Moore ratio Li:(Ni 0.5 co 0.2 mn 0.3 )(OH) 2 =1.03:1 Weigh lithium acetate and ternary c...

specific Embodiment approach 3

[0041] Specific embodiment three: In this embodiment, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0042] 1. Mole ratio Li:Ni 0.42 co 0.16 mn 0.42 (OH) 2 =1.10:1 Weigh lithium carbonate and ternary cathode material precursors, mix them uniformly in a mixed solution of deionized water and ethanol, raise the temperature from room temperature to 500 °C at a heating rate of 20 °C / min, pre-calcine for 5 h, and then Raise to 1000°C at the same heating rate and calcined for 10 h to obtain the ternary cathode material;

[0043] 2. Weigh the ternary positive electrode material with a molar ratio of 1:0.015:0.002, the above-mentioned lithium source, and nano-TiO 2 , uniformly mixed in a mixed solution of deionized water and ethanol;

[0044] 3. Put the above mixture into an industrialized kiln in an air atmosphere, and calcinate it at a heating rate of 20°C / min from room temperature to 850°C for 5 hours to ...

technical field

[0001] The invention belongs to the technical field of material synthesis, and relates to a preparation method of a lithium-ion battery cathode material, in particular to a preparation method of a long-life, high-capacity lithium-ion battery ternary cathode material. Background technique

[0002] As another secondary battery after lead-acid batteries, nickel-cadmium batteries and nickel-metal hydride batteries, lithium-ion batteries have significant advantages such as no memory effect, high working voltage, and low self-discharge rate. preferred technology. In recent years, lithium-ion batteries have been widely used in the field of high-energy batteries, and gradually expanded to the field of power batteries.

[0003] In the composition of lithium-ion batteries, the cathode material determines the main performance of the battery. Lithium-ion battery ternary material LiNi 1-x-y co x mn y o 2 Due to the advantages of high gram capacity, good safety, low ...

Examples

specific Embodiment approach 1

[0027] Specific implementation mode 1: In this implementation mode, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0028] 1. Weigh nickel sulfate, cobalt sulfate, and manganese sulfate respectively in a molar ratio of 1:1:1, and dissolve them in deionized water and mix them evenly. Add 2 mol / L precipitant sodium carbonate and a certain amount of complexing agent ammonia water one by one. Add it dropwise, control the molar ratio of metal salt to ammonia water to be 1:0.75, the pH value of the reaction is between 8 and 9, react at 60°C for 12 h, and stir continuously at a speed of 600 rpm, and suction filter after the reaction. Wash repeatedly to remove impurities, dry at 80°C for 24 h, and synthesize the precursor of ternary cathode material (NiCoMn)(OH) 2 , and its D50 particle size is 8 microns.

[0029] Ternary precursors are also available commercially.

[0030] 2. Molar ratio Li:NiCoMn(OH) 2 =1.05...

specific Embodiment approach 2

[0034] Specific implementation mode 2: In this implementation mode, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0035] 1. Weigh nickel sulfate, cobalt sulfate, and manganese sulfate respectively in a molar ratio of 5:2:3, and dissolve them in deionized water and mix them uniformly. 2mol / L precipitant sodium hydroxide and a certain amount of complexing agent ammonia Add it dropwise, control the molar ratio of metal salt to ammonia water to be 1:0.75, the pH value of the reaction is between 10~11, react at 60°C for 12h, and stir continuously at a speed of 600 rpm. Wash, remove impurities, dry at 80°C for 24h, and synthesize the precursor of ternary cathode material (Ni 0.5 co0.2 mn 0.3 )(OH) 2 , and its D50 particle size is 9 microns.

[0036] Ternary precursors are also available commercially.

[0037] Two, Moore ratio Li:(Ni 0.5 co 0.2 mn 0.3 )(OH) 2 =1.03:1 Weigh lithium acetate and ternary c...

specific Embodiment approach 3

[0041] Specific embodiment three: In this embodiment, the secondary lithium-added calcined ternary positive electrode material is prepared according to the following steps:

[0042] 1. Mole ratio Li:Ni 0.42 co 0.16 mn 0.42 (OH) 2 =1.10:1 Weigh lithium carbonate and ternary cathode material precursors, mix them uniformly in a mixed solution of deionized water and ethanol, raise the temperature from room temperature to 500 °C at a heating rate of 20 °C / min, pre-calcine for 5 h, and then Raise to 1000°C at the same heating rate and calcined for 10 h to obtain the ternary cathode material;

[0043] 2. Weigh the ternary positive electrode material with a molar ratio of 1:0.015:0.002, the above-mentioned lithium source, and nano-TiO 2 , uniformly mixed in a mixed solution of deionized water and ethanol;

[0044] 3. Put the above mixture into an industrialized kiln in an air atmosphere, and calcinate it at a heating rate of 20°C / min from room temperature to 850°C for 5 hours to ...

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