LiOH (lithium hydroxide) and Li2CO2 content measurement method in high-nickel ternary materials

Abstract

The invention discloses an LiOH (lithium hydroxide) and Li2CO2 content measurement method in high-nickel ternary materials. The method includes the steps of 1), adding the high-nickel ternary materials into 5-10 mass times of ethyl alcohol, stirring under vacuum for 20-30 minutes, filtering after standing, and performing cool drying; 2), adding the high-nickel ternary materials subjected to cool drying to 5-10 times of deionized water, performing ultrasonic dispersion and taking supernatant liquid after filtration; 3), adding an indicator of 2-3 drops of phenolphthalein, performing titration with hydrochloric acid, terminating titration when solution color turns from red to colorless, and calculating the content of LiOH according to the amount of the hydrochloric acid consumed; 4), continuously adding the indicator of methyl red in the solution, performing titration by using hydrochloric acid, terminating titration when the solution color turns from yellow to red, and calculating the content of Li2CO according to the amount of the hydrochloric acid consumed. The method is simple in step, low in requirement on equipment and high in operability result accuracy.

Description

technical field [0001] The invention relates to the technical field of lithium battery material testing, in particular to LiOH and Li in a high-nickel ternary material. 2 CO 3 method for the determination of content. Background technique [0002] High-nickel ternary materials (such as: NCM622, NCM811) are widely used by various battery manufacturers due to their high gram specific capacity and good cycle performance; but high-nickel ternary materials are very easy to interact with CO2 and H 2 O generates LiOH and Li 2 CO 3 , while LiOH reacts with LiPF6 in the electrolyte to generate HF, Li 2 CO 3 Can cause severe flatulence when stored at high temperatures. [0003] Although high-nickel ternary materials will introduce LiOH and Li 2 CO 3 , but after the material is processed in the later stage, the content of LiOH and Li2CO3 will be very small; the main reason is that during the battery manufacturing process, the material is inevitably in contact with the air, espec...

AI Technical Summary

Problems solved by technology

[0005] The present invention is to solve the problems of LiOH and Li in the high-nickel ternary material of the prior art. 2 CO 3 The determination method of content has uncontrollable titration end point, waste of time and materials, and high requirements on equipment. It provides a high-nickel ternary material with simple process steps, low requirements on equipment, strong operability and high accuracy of results. LiOH and Li 2 CO 3 Determination method of content