A New Synthetic Route of LiFePO4 Nanoparticles from Molten Ingot

Abstract

LiFePO4 (LFP) nano-particles have been obtained by grinding ingot synthesized in the molten state. This process, followed by jet milling, and then wet milling, provides a simple way to obtain powders with monitored size of the particles in the whole range from macroscopic to 25 nm, although at this stage, we find that these particles tend to segregate to form secondary particles of size ~100 nm. The electrochemical performance of LFP particles has been evaluated in Li/1M LiPF6 in EC:DEC (1:1)/C-LiFePO4 cells. After carbon coating, LFP particles can be obtained free from any impurity, with a high rate capability. Even with an amount of carbon limited to 2 wt.% appropriate to commercial batteries, the capacity is 157 mAh/g at 0.1C; 58 mAh/g at 10C without capacity fading after 60 cycles.