On April 10, 2024, according to the announcement of the State Intellectual Property Office, Guangdong Huiyun Titanium Co., Ltd. applied for a project titled "A High-Performance and Stable Iron Phosphate and Its Preparation Method", Publication No. CN117842956A, application date is January 2024.
The patent abstract shows that the present invention discloses a preparation method of iron phosphate with high performance stability, which comprises the following steps: S1, adding iron oxide into a pre-heated acid solution, wherein the acid solution comprises phosphoric acid and nitric acid, the molar ratio of the iron oxide to the acid solution is 1:(8 - 20), and the molar ratio of phosphoric acid and nitric acid is (2‑2.5):(4‑12), control the temperature and stirring rate to react;S2, slowly drop ammonia solution while stirring, adjust the pH value to 2‑5, age, suction filter, and wash;S3, calcining, dewatering, grinding, and sieving the solid after S2 washing to obtain iron phosphate powder. The method disclosed by the invention does not form iron phosphate complexes and does not contain other impurities during the reaction process, and high-purity iron phosphate can be obtained. The prepared iron phosphate product particles have high uniformity and consistency and meet the standards of battery-grade anhydrous iron phosphate for lithium iron phosphate. The lithium iron phosphate battery prepared by using the iron phosphate prepared by the invention has excellent discharge efficiency.
