Clean production method of co-precipitation process positive material carbonate precursor

Abstract

The invention discloses a clean production method of a co-precipitation process positive material carbonate precursor. The method mainly comprises the following steps: (1) respectively preparing a metal salt solution, an alkali solution and a complexing agent solution, adding the metal salt solution, the alkali solution and the complexing agent solution into a main reactor, and carrying out co-precipitation reaction under a certain condition; (2) dehydrating, washing and drying a solid precipitation product of the main reactor to prepare the carbonate precursor; (3) collecting supernatant liquor of the main reactor and centrifugally dehydrated wastewater and separating through an RO membrane, circularly taking pure water as washing water, and adding concentrated water into a secondary reactor; (4) adding the alkali solution and mixing the concentrated water components for carrying out secondary co-precipitation reaction, and circulating the solid precipitation product to the main reactor; and (5) efficiently evaporating and crystallizing the supernatant liquor of the secondary reactor to prepare a sodium sulfate by-product. The whole production process is clean; the metal salts arecompletely precipitated; the yield of the product is high; other chemicals do not need to be added; meanwhile, the method is free of emission of wastewater and free of heavy metal pollution problem.

Description

technical field [0001] The invention relates to a clean production method of a carbonate precursor of a positive electrode material by a co-precipitation method. Background technique [0002] As a secondary battery, lithium-ion batteries have been widely commercialized in 3C, electrical tools, electric bicycles and other fields, and also have good application prospects in the fields of hybrid electric vehicles, pure electric vehicles and energy storage. Lithium-ion batteries are mainly composed of positive electrodes, negative electrodes, electrolytes and separators, and the finished positive electrode materials are mainly prepared by mixing and calcining positive electrode material precursors and lithium salts. [0003] At present, there are three main types of precursors of cathode materials for lithium-ion batteries produced by co-precipitation method: hydroxides, carbonates and oxides. The existing relatively mature technologies are mainly hydroxide and carbonate precur...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the technical defects of the above-mentioned prior art, the present invention provides a clean production method for the carbonate precursor of positive electrode material by co-precipitation method. By setting RO membrane and secondary reaction kettle, the whole production process is clean. Production, in which the metal salt is completely precipitated, the product yield is high, no need to add other chemicals, and at the same time achieve zero discharge of waste water, no heavy metal pollution problem

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