Simple and convenient method for reducing pH value of ternary cathode material of lithium-ion battery

The invention discloses a simple and convenient method for reducing the pH value of a ternary cathode material of a lithium-ion battery, and belongs to the field of electrochemistry. The pH value of the lithium-ion battery cathode material is reduced by an organic solution system of ascorbic acid. The method is firstly characterized in that the relationship between the concentration of the ascorbic acid and the concentration of a lithium-ion cathode material turbid liquid meets the condition that A is less than or equal to 0.015B and greater than or equal to 0.001B; A is the concentration of the ascorbic acid; the unit is g/L; B is the concentration of the cathode material; the unit is g/L; and meanwhile, the concentration A of the ascorbic acid can further meet the relational expression that A is less than or equal to 0.8s (s is the solubility s of the ascorbic acid in a corresponding organic solvent, and the unit is g/100g). The method is secondly characterized in that the ascorbic acid-modified lithium-ion cathode material is few in required washing times after being centrifugally separated. The method is simple in process and low in cost; and the cathode material with the improved discharge rate capability can be obtained by adjusting the VC concentration.