Method for washing nickel-cobalt-manganese ternary precursor to remove impurity sodium

Abstract

The invention discloses a method for washing a nickel-cobalt-manganese ternary precursor to remove impurity sodium, which comprises the following steps: S1, carrying out solid-liquid separation on a solid-liquid mixture of a nickel-cobalt-manganese ternary precursor crude product to obtain a solid ternary precursor crude product; s2, washing the solid ternary precursor crude product by using a sodium hydroxide solution to remove sulfate ions on the surface, and then dehydrating to obtain a dehydrated solid-phase substance; s3, washing the dehydrated solid-phase substance by using a dimethyl sulfoxide aqueous solution, and then carrying out solid-liquid separation to obtain a solid material; and S4, washing the solid material with pure water, and dehydrating and drying to obtain a finished product. The method has the advantage that the sodium ion content of the nickel-cobalt-manganese ternary precursor can be remarkably reduced.

Description

technical field [0001] The invention relates to a production process of a lithium ion battery cathode material precursor, in particular to a method for removing impurities in the precursor. Background technique [0002] Lithium-ion batteries are mainly composed of positive electrode materials, negative electrode materials, separators, and electrolytes. The positive electrode material accounts for more than 40% of the total cost of the lithium battery, and the performance of the positive electrode material directly affects various performance indicators of the lithium battery. The ternary precursor is the main raw material of the ternary cathode material, in other words, the quality of the ternary precursor directly determines the performance of the ternary cathode material. [0003] In addition to the conventional tap density, specific surface area, and morphology parameters of the ternary precursor, the impurities contained in the product will also affect the production an...

AI Technical Summary

Problems solved by technology

These two ways of existence will not decrease in the subsequent sintering process of the ternary cathode material. On the contrary, some sodium ions may occupy lithium ion sites during the sintering process, resulting in an irreversible decrease in the performance of the ternary cathode material.

The sulfur element will produce corresponding polluting gas during the calcination process of ternary materials in the later stage, and cause corrosion to the calcination equipment

Images