Method for determining content of residual lithium carbonate and lithium hydroxide on surface of positive electrode material

Abstract

The invention discloses a method for determining the content of residual lithium carbonate and lithium hydroxide on the surface of a positive electrode material. The method comprises the following steps: accurately weighing a positive electrode material sample in a conical bottle by an electronic scale, and then weighing deionized water to be added, wherein the mass ratio of the positive electrodematerial sample to the deionized water is 3 to 10; adding a magnetic stir bar, introducing nitrogen to discharge the air in the conical bottle, performing low-speed stirring on a magnetic stirrer with the magnetic stir bar, and then performing suction filtration; accurately removing 10ml of the filtrate obtained in the step I by a pipette, placing the filtrate in the conical bottle, adding a dropof 0.1 percent phenolphthalein indicator in order that the color of the solution becomes pink, titrating the solution with a 0.01mol / L hydrochloric acid standard solution until the pink solution is completely turned into a colorless solution, recording the dosage of hydrochloric acid (V<1>), and adding two drops of 0.1 percent methyl red indicator into the colorless solution obtained in the stepII in order that the solution is yellow; continuing to titrate with the standard hydrochloric acid solution until the solution turns red, and recording the dosage of the hydrochloric acid (V<2>); andcalculating the result. The method has the advantages of accurate testing and low cost.

Description

technical field [0001] The invention relates to a test method for positive electrode materials, in particular to a method for measuring the content of lithium carbonate and lithium hydroxide remaining on the surface of positive electrode materials. Background technique [0002] At present, as a new type of energy-saving material, the positive electrode material has complex components, and the amount of residual carbonate and hydroxide on the surface of the positive electrode material directly affects the application characteristics of the battery. The disadvantages of the determination method of hydroxide content are: inaccurate measurement, large error, long cycle of test results, and Chen Bengao. Contents of the invention [0003] In order to ensure the quality of the positive electrode material, the object of the present invention is to provide a method for measuring the residual lithium carbonate and lithium hydroxide content on the surface of the positive electrode ma...

AI Technical Summary

Problems solved by technology

[0002] At present, as a new type of energy-saving material, the positive electrode material has complex components, and the amount of residual carbonate and hydroxide on the surface of the positive electrode material directly affects the application characteristics of the battery. The disadvantages of the determination method of hydroxide content are: inaccurate measurement, large error, long cycle of test results, Chen Bengao

Images