Nickel-cobalt-manganese-aluminum quaternary precursor, positive electrode material and preparation method thereof

Abstract

The invention discloses a nickel-cobalt-manganese-aluminum quaternary precursor, a positive electrode material and a preparation method thereof. According to the nickel-cobalt-manganese-aluminum quaternary precursor, nickel-cobalt-manganese-aluminum blocky primary particles are tightly agglomerated to form secondary spherical particles; and the chemical formula of the nickel-cobalt-manganese-aluminum quaternary precursor is NixCoyMnzAl(1-x-y-z)(OH)2, x is more than 0.7 and less than 0.9, y is more than 0.05 and less than 0.10, z is more than 0.05 and less than 0.10, and 1-x-y-z is more than 0 and less than 0.10. The invention further discloses a preparation method of the nickel-cobalt-manganese-aluminum quaternary precursor, a positive electrode material and a preparation method of the positive electrode material. The quaternary precursor and the positive electrode material are high in primary particle sphericity degree, uniform in distribution, tight in growth and good in consistency, the structure of the material is kept stable in the charging and discharging process, and the quaternary precursor and the positive electrode material have the advantages of high energy density, good cycle performance, highly reversible charging and discharging reaction and good large rate performance. The method is simple in process, low in reaction temperature, low in raw material cost and suitable for industrial production.

Description

technical field [0001] The invention relates to a quaternary precursor, a positive electrode material and a preparation method, in particular to a nickel-cobalt-manganese-aluminum quaternary precursor, a positive electrode material and a preparation method. Background technique [0002] With the gradual increase in the energy density of power batteries, ternary materials have become the mainstream materials for power batteries, and driven by the increasing specific energy, ternary materials are also developing towards high-nickel materials with higher capacity, nickel-cobalt-aluminum Lithium oxide (NCA) and lithium nickel cobalt manganese oxide (NCM) have become strong contenders for the next generation of high specific energy lithium-ion battery cathode materials due to their high capacity characteristics, and NCA materials are superior to NCM materials in terms of cycle performance, but , the particles are more prone to pulverization and fragmentation during the cycle, and...

AI Technical Summary

Problems solved by technology

However, the above method has the following technical defects: 1) In the method, the nickel-cobalt-manganese-aluminum precursor material is prepared by the traditional co-precipitation method, and the co-precipitation reaction process involves more reaction conditions, which has a great impact on the synthesis process of the material , especially for the preparation of gradient materials; 2) The coating process of graphene and metal framework compounds used, especially the dispersion effect of graphene oxide is poor, and the conditions for reduction treatment are harsh; 3) This method does not clearly indicate that the coating The electrochemical performance of the positive electrode material before coating cannot reflect the improvement of the material by adding aluminum after coating and modification with graphene, and the hydrothermal reaction with graphene in the reaction kettle in the later stage requires high hydrothermal reaction conditions and is difficult to control. The synthesis process is more complex

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