Preparation method of microscale single-crystal ternary positive electrode material

Abstract

The invention discloses a preparation method of a microscale single-crystal ternary positive electrode material. The preparation method comprises the steps of sanding and mixing raw materials; grinding nickel carbonyl, cobalt carbonyl, manganese carbonyl and tert-butyllithium in a grinding machine at a high speed according to a mole ratio being (0.2-0.6):(0.2-0.4):(0.2-0.5):(0.95-1.15), wherein the linear speed a of the grinding machine during working is equal to 20-35m / s, a grinding medium is tungsten particle, the particle size b is equal to 0.1-5 millimeter, and the grinding time is b*600 / ahours; and sintering a material, in which the material is sintered in an air atmosphere by a conventional round disc electric furnace to obtain the microscale single-crystal ternary positive electrode material, wherein the electric furnace power P is 1,500-3,000W, the electric furnace wire length L is 5-15 meters, and the sintering time is P*0.3 / L hours. The microscale single-crystal ternary positive electrode material synthesized by the process has the advantages of low specific area, concentrated grain distributed, high thermal stability and the like; and moreover, since the microscale single-crystal ternary positive electrode material has relatively low specific surface area, the contact degree of the material and an electrolyte is relatively low, and the cycle lifetime of the materialis greatly prolonged compared with a conventional spherical agglomeration material.

Description

technical field [0001] The invention belongs to the technical field of inorganic new energy materials, and in particular relates to a preparation method of a micron-sized single crystal ternary positive electrode material. Background technique [0002] At present, lithium-ion batteries are widely used and reliable power sources for electric vehicles. With the development of electric vehicles, the requirements for battery energy density are getting higher and higher. At present, lithium-ion power batteries mostly use lithium iron phosphate and NCM ternary as positive electrode materials. Due to the low working voltage of lithium iron phosphate materials and the low compaction density of the electrodes, the overall energy density of the assembled batteries is not high. However, although the ternary cathode materials have high energy density, because their large-scale preparation method is often liquid-phase co-precipitation method, the products obtained are mostly micron-size...

AI Technical Summary

Problems solved by technology

At present, lithium-ion power batteries mostly use lithium iron phosphate and NCM ternary as positive electrode materials. Due to the low working voltage of lithium iron phosphate materials and the low compaction density of the electrodes, the overall energy density of the assembled batteries is not high. However, although the ternary cathode materials have high energy density, because their large-scale preparation method is often liquid-phase co-precipitation method, the products obtained are mostly micron-sized spherical aggregates, and these aggregates are coated on the electrode. During the cloth rolling process, the powder will be broken and dropped, which will have a certain impact on the performance of the battery