US 12,466,734 B2
Preparation method of high-safety high-capacity lithium manganese iron phosphate
Ji Yang, Huangshi (CN); Yihua Wei, Huangshi (CN); Jie Sun, Huangshi (CN); Zhonglin He, Huangshi (CN); Jianhao He, Huangshi (CN); Shuo Lin, Huangshi (CN); Cheng Xu, Huangshi (CN); Pingjun Lin, Huangshi (CN); Chao Liu, Huangshi (CN); Menghua Yu, Huangshi (CN); Hongfu Qi, Huangshi (CN); Xiong Wang, Huangshi (CN); and Zhengchuang Cheng, Huangshi (CN)
Assigned to HUBEI RT ADVANCED MATERIALS GROUP COMPANY LIMITED, Huangshi (CN)
Filed by HUBEI RT ADVANCED MATERIALS GROUP COMPANY LIMITED, Huangshi (CN)
Filed on Nov. 3, 2022, as Appl. No. 17/979,792.
Claims priority of application No. 202210579213.9 (CN), filed on May 25, 2022; and application No. 202210935979.6 (CN), filed on Aug. 5, 2022.
Prior Publication US 2023/0060433 A1, Mar. 2, 2023
Int. Cl. C01B 25/45 (2006.01); C01B 25/37 (2006.01)
CPC C01B 25/45 (2013.01) [C01B 25/375 (2013.01); C01B 25/377 (2013.01); C01P 2004/61 (2013.01); C01P 2006/40 (2013.01)] 7 Claims
 
1. A preparation method of lithium manganese iron phosphate, comprising the following steps:
S1: mixing an iron source, a phosphorous source and an antioxidant into a solution, introducing nitrogen into the solution to serve as a protective gas to prevent oxidization, and synthesizing a ferrous phosphate precursor through a co-precipitation process, sintering the obtained ferrous phosphate precursor, and then removing all crystallized water to obtain an anhydrous ferrous phosphate precursor;
S2; mixing a manganese source, a phosphorous source and an antioxidant into a solution, introducing nitrogen into the solution to serve as a protective gas to prevent oxidization, and synthesizing a manganese phosphate precursor through the co-precipitation process, and sintering the obtained phosphorous source to obtain an anhydrous manganese phosphate precursor;
S3: adding lithium phosphate and deionized water into the anhydrous ferrous phosphate precursor obtained in step S1, and performing ball milling and wet sanding to obtain slurry A;
S4; adding lithium phosphate, an organic carbon source, a dispersant, a dopant and deionized water into the anhydrous manganese phosphate precursor obtained in step S2, and performing ball milling and wet sanding to obtain slurry B; and
S5; mixing the slurry A obtained in step S3 with the slurry B obtained in step S4 and performing ball milling, spray drying, sintering and air jet pulverization to obtain high-safety high-capacity lithium manganese iron phosphate.