Preparation method of high-capacity lithium nickel cobalt aluminate

Abstract

The invention relates to a preparation method of a high-capacity lithium ion battery cathode material of lithium nickel cobalt aluminate. The preparation method comprises: adding a nickel-containing compound, a cobalt-containing compound, a lithium-containing compound, and an aluminium-containing compound into a high temperature-resistant ball-milling tank and performing uniform mixing; putting the tank into a mechanical device capable of heating and rotating; performing ball milling at a room temperature; performing mixing for 5-20h; sintering the reactants in the ball-milling tank in the presence of air flow or oxygen flow at two temperature segments while keeping ball milling, wherein firstly, elevating the temperature to 400-600 DEG C in the presence of air flow or oxygen flow and performing sintering for 2-10h, and elevating the temperature to 700-900 DEG C in the presence of air flow or oxygen flow and performing sintering for 5-30h; performing cooling while performing ball milling till the temperature is relatively low; and opening the device to obtain cathode material powder of lithium nickel cobalt aluminate. The method is simple in technology, and raw materials can be completely mixed through high-temperature ball milling to obtain the cathode material of lithium nickel cobalt aluminate. In a voltage range of 3.0-4.2V and under a rate of 0.2C, the cathode material has an initial discharge specific capacity higher than 180mAH / g and has excellent cycle performance.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and relates to a preparation method of nickel cobalt lithium aluminate, an anode material of lithium ion batteries, which has excellent electrochemical performance. Background technique [0002] As a new generation of green and environment-friendly power supply, lithium battery has the advantages of light weight, small size, high discharge platform, large capacity, and cycle [0003] With the advantages of long ring life and no memory effect, it is widely used in mobile phones, cameras, notebook computers, power tools, electric bicycles and electric vehicles. At present, the research hotspots of cathode materials for lithium-ion batteries are mainly focused on LiCoO 2 , LiNiO 2 , LiMn 2 o 4 、LiFePO 4 and Li 4 Ti 5 o 12 on several materials. Traditional LiNi0 2 Although it has a high discharge specific capacity, its preparation is difficult, it is prone to phase change duri...

AI Technical Summary

Problems solved by technology

The co-precipitation method can obtain a pure-phase nickel-cobalt-lithium aluminate material with uniform particle size and good electrochemical performance, but its process control is difficult and pollutes the environment

However, the particle size of the material obtained by the traditional high-temperature solid-state method is uneven, the agglomeration phenomenon is serious, and the electrochemical performance of the material is poor. Moreover, for the nickel-cobalt-lithium-aluminate material, the traditional static state calcination, although it is flowing In an oxygen atmosphere, the material on the surface can be fully oxidized, but it is difficult for oxygen to diffuse to the middle or bottom of the material, and unoxidized Ni will inevitably remain in the obtained product. 2+ , resulting in a capacity loss of the material

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