A method for optimizing particle size distribution during the preparation of nickel-cobalt-manganese precursor materials

Abstract

The invention discloses a method for optimizing the size distribution during the process of preparation of a nickel-cobalt-manganese precursor material, which is represented by a chemical formula: NixCoyMn<1-x-y>(OH)2, wherein 0.2<x<0.8 and 0.2<y<0.8. The preparation device of the nickel-cobalt-manganese precursor material comprises two reactors, which are serially connected by overflow pipes. The reactor I is provided with a feed pipe I and a stirring device I, and the reactor II is provided with a feed pipe II and a stirring device II. The preparation method of the nickel-cobalt-manganese precursor material comprises the following steps: (1) preparing a first solution, wherein the total concentration of the nickel ion, cobalt ion, and manganese ion is 1.0 to 1.5 mol / L, and the concentration of a complexing agent is 1 to 5 g / L; (2) preparing a second solution containing sodium hydroxide with a concentration of 5-10 mol / L; (3) introducing the first solution and the second solution into the reactor I from the feed pipe I, simultaneously introducing the first solution and the second solution into the reactor II from the feed pipe II; and controlling the technology parameters of the reactor I and the reactor II. Through controlling the feasible technology parameters, a nickel-cobalt-manganese precursor with even and stable particle size distribution can be obtained.

Description

technical field [0001] The invention relates to a method for optimizing particle size distribution, in particular, the invention relates to a method for optimizing particle size distribution during the preparation of nickel-cobalt-manganese precursor materials. Background technique [0002] Lithium-ion battery has the advantages of high voltage, large specific capacity, safety, and environmental protection, and has attracted widespread attention. The lithium-ion battery is mainly composed of three parts: positive electrode material, negative electrode material and electrolyte, among which the positive electrode material plays the most critical role in improving the overall performance of lithium-ion batteries. [0003] At present, among the positive electrode materials in the market, lithium cobalt oxide, lithium cobalt manganese oxide and lithium manganate basically occupy the dominant share. The precursors of these positive electrode materials are cobalt oxide / cobalt hydro...

AI Technical Summary

Problems solved by technology

[0004] In the Chinese patent CN 201320092391.X, "a reaction system with controllable particle size" is mentioned in which a series of equipment such as a circulation device, a classification device, and a clarification device are added to adjust the particle size distribution. Due to the increased investment in the process, the operation Complicated, not suitable for industrialized production; ("a continuous type cobalt tetroxide production device" disclosed in Chinese patent 201220518689.3 proposes to connect three reactors in series to allow the reaction particles to grow step by step. Since there is no feed to continue to participate in the reaction, There are certain limitations in the control range of the particle size distribution width); Chinese patent 201310142370.4 discloses a preparation method for a small particle size nickel-cobalt lithium manganese oxide precursor, but does not mention how to control the particle size distribution method

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