Abstract:The principle of impurity removal from acid leaching solution of spent lithium batteries was mainly studied. The non-extraction impurity removal process, i.e., two-stage acid leaching, neutralization removal of Fe and Al, flocculation precipitation removal of F, and depth removal of impurities, was adopted. In the impurity removal process, since the acid leaching solution contains high concentrations of Ni, Co, and Mn ions, the types and concentrations of neutralizers will affect the loss rates of Ni, Co, and Mn. Through process control and neutralization agent debugging, 10% CaCO3 was selected as the neutralization agent for removing of Fe, Al, and F. Content of Fe, Al, Cu, and F can be reduced from 0.20, 9.76, 0.58, and 1.66 g/L to 0.01, 0.02, 0.01, and 29.86 mg/L, respectively, which meets the impurity standard requirements of ternary precursor solution. At this time, the loss rate of Ni, Co, and Mn is only 0.96%, 0.04%, and 0.01%, respectively, which is all within the acceptable range.