Method of preparing battery-grade lithium carbonate from lithium-rich solution being high in content of impurities

The invention discloses a method of preparing battery-grade lithium carbonate from a lithium-rich solution being high in content of impurities. The method includes the steps of: a) pumping the lithium-rich solution into a reaction kettle and increasing the temperature to 60-80 DEG C, adding a first impurity remover and performing a temperature-maintained stirring reaction, regulating the pH to 11-12, and continuously performing the temperature-maintained stirring reaction and filtering the reaction product to obtain a refined lithium-rich solution; b) adding deionized water to the reaction kettle, and adding sodium carbonate with stirring clarification to obtain a sodium carbonate solution, adding a second impurity remover and sodium hydroxide to carry out a stirring reaction, and filtering the solution to prepare a refined sodium carbonate solution; c) performing a reaction to the refined lithium-rich solution and the refined sodium carbonate solution to obtain lithium carbonate slurry; d) performing solid-liquid separation to the lithium carbonate slurry to obtain lithium carbonate wet solid and a lithium precipitation mother liquid; e) leaching the lithium carbonate wet solid by deionized water, placing the solid into a washing trough, adding deionized water to perform re-slurrying washing, and performing solid-liquid separation to obtain a lithium carbonate wet material; and f) drying the lithium carbonate wet material to prepare the battery-grade lithium carbonate.