Study of Precursor Preparation of Battery-Grade Lithium Iron Phosphate

In this paper, ferric sulfate was extracted from titanium white waste acid as the iron source of lithium iron phosphate precursor. The ferric sulfate obtained from titanium white waste acid, ammonium phosphate tribasic, and ammonia hydroxide were used as raw materials through liquid precipitation method to obtain iron phosphate as the precursor of lithium iron phosphate. Under the premise of ensuring the synthesis of FePO4 center dot 2H(2)O, the effects of the pH, synthesis temperature and reaction time on the particle size of the resulting product were investigated. The results showed that high purity amorphous FePO4 center dot 2H(2)O with a median diameter of 38.4 mu m was acquired through the condition of pH = 2, T = 25 degrees C, and t = 12 h, which meets the requirements for preparation of lithium iron phosphate and realizes high value-added utilization of discarded resources.