Wang Xiaohui, researcher of Institute of metals, Chinese Academy of Sciences and Zhu kongjun, Professor of Nanjing University of Aeronautics and Astronautics, have made progress in the field of green and efficient synthesis of high-performance nano lithium iron phosphate

The heart of an electric vehicle is an electric motor driven by a battery or fuel cell With the increasing demand for electric vehicles, the demand for high-quality batteries is also increasing As the first choice of battery technology development, lithium-ion battery cathode material is one of the key components to determine battery performance LiFePO 4 has excellent thermal stability, high reversibility and acceptable working voltage, so it has a significant competitive advantage as a positive material Previously, most of the published papers have used solvothermal method to prepare LiFePO 4 nanoparticles, and the products have good electrochemical properties, but these methods have low yield, high cost, and can not achieve large-scale production Compared with solvothermal method, the cost of preparation of LiFePO 4 by hydrothermal method is lower, but the electrochemical performance of the product is poor Moreover, due to the limitation of reaction (3lioh + FeSO4 + H3PO4 = LiFePO4 + Li2SO4), the effective utilization of lithium source is less than one third, no matter in solvothermal or hydrothermal synthesis Therefore, how to use hydrothermal method to prepare nano-sized LiFePO 4 with high performance and recycle lithium source is not only a technical problem to realize large-scale hydrothermal method to prepare nano-sized LiFePO 4, but also an important scientific problem Recently, Wang Xiaohui, a researcher at the Institute of metals, Chinese Academy of Sciences, and Zhu kongjun, a professor at Nanjing University of Aeronautics and Astronautics, worked together to increase the nucleation rate by reducing the nucleation window time on the basis of in-depth understanding of the growth mechanism of lamer nucleation, and prepared LiFePO 4 nanoparticles in pure water by microwave hydrothermal synthesis At the same time, the most valuable LiOH in the filtrate was recovered and reused by the precipitant The effective utilization rate of lithium source exceeded 90%, which greatly reduced the production cost The LiFePO 4 nanoparticles prepared by the authors have the highest yield (1.3 mol / L) so far, and show excellent electrochemical performance After 1000 charge / discharge cycles at 3C, the nano material can still maintain 88% of its initial capacity, which can meet the practical application of large-scale energy storage This work took the lead in realizing the green and efficient synthesis of high-performance nano LiFePO 4 in the synthesis environment of pure water, which will strongly promote its large-scale production The results were published in green chemistry (DOI: 10.1039 / c8gc02584c).