Enhancement of uniformity and performance of LiFePO4/C cathode material prepared via a continuous rotating reactor

Abstract

An innovative high mixing continuous rotating reactor technology (HMCRR) was firstly applied in the preparation of LiFePO4/C with high uniformity. In this study, di-hydrous FePO4 with different morphology were prepared by HMCRR and calcined to obtain LiFePO4/C cathode materials to verify the feasibility and exceptional properties of the new facile technology. Multiple characterization results indicated that hydrous iron phosphate material obtained by HMCRR under strong shear and efficient mass transfer was micro spherical fine-sized FePO4 composed of uniform nanoplates with excellent crystallinity, while FePO4 synthesized in a conventional stirred tank had exasperate morphology with uneven primary particle size indicating a drawback at large processing capacity. Further made LiFePO4/C inheriting the enhanced properties of FePO4 by HMCRR, showing mesoporous structure with larger specific surface area and more uniform morphology composed of nano primary particles compared with the traditional one. The electrochemical analysis demonstrated that the application of high mixing continuous rotating reactor technology in the synthesis procedure of LiFePO4/C would equip the cathode material with excellent cycling stability and more outstanding high-rate capacity via fast ion diffusion kinetics and improved electronic conductivity provided by advantageous morphology, with discharge capacity at 10C reaching around 125.4 mAh·g−1.