Método para preparar carbonato de litio grado bateria desde sal de carbonato de litio de lago

The present application discloses a method for preparing battery-grade lithium carbonate from salt lake lithium carbonate, and belongs to the technical field of battery materials. The method includes the following steps: subjecting the salt lake lithium carbonate to leaching with an acid solution, subjecting a solution obtained after the leaching to a reaction with a sodium carbonate solution, and subjecting a resulting reaction system to pressure filtration to obtain crude lithium carbonate; washing the crude lithium carbonate with water to obtain a first water-washing solution, and subjecting the washed crude lithium carbonate to leaching once again with an acid solution; adjusting a pH with calcium hydroxide to 10 to 12 for impurity removal to obtain an impurity-removed solution, adding sodium carbonate to the impurity-removed solution, and thoroughly stirring a resulting mixture to obtain a mixed solution; allowing the mixed solution to pass through a resin column for calcium removal by adsorption to obtain a calcium-removed solution; subjecting the calcium-removed solution to a reaction with a sodium carbonate solution, and subjecting a resulting reaction system to pressure filtration to obtain lithium carbonate; and washing the lithium carbonate with an aqueous solution of carbon dioxide to obtain a second water-washing solution and water-washed lithium carbonate, and oven-drying the water-washed lithium carbonate to obtain the battery-grade lithium carbonate. The present application can effectively prepare salt lake lithium carbonate into battery-grade lithium carbonate with extremely high purity and lithium phosphate, and effectively improve a yield of lithium. The present application relates to the technical field of battery materials, and discloses a method for preparing battery-grade lithium carbonate by using salt lake lithium carbonate, comprising the following steps: leaching the salt lake lithium carbonate by using an acid solution; enabling a solution obtained by acid leaching to react with a sodium carbonate solution, and carrying out filter pressing to obtain crude lithium carbonate; using water to wash the crude lithium carbonate to obtain a first water washing solution; leaching the washed lithium carbonate again by using the acid solution; adding calcium hydroxide to adjust the pH value to 10-12, and removing impurities to obtain an impurity-removed solution; adding sodium carbonate into the impurity-removed solution, and uniformly sti