Synthesis and Electrochemical Properties of LiMPO4 (M = Fe, Mn, Co) Nanocrystals in Polyol Medium

Olivine structured LiMPO4 (M = Fe, Mn, Co) was synthesized by the solvothermal process using a polyol medium of diethylene glycol (DEG) without any further heating as a post procedure. The synthesized LiMPO4 nanoparticles exhibited an average length of 200 approximately 400 nm, width of 200 approximately 300 nm, and thickness of 20 approximately 50 nm, and with well dispersed plate and rod morphologies. The Rietveld-refined X-ray diffraction (XRD) pattern of LiFePO4 exhibited a good fit with an olivine structure (space group: Pnma) and no undesirable impurity phases. The LiFePO4 nanocrystals showed a reversible capacity of 167 mAh/g, equating to a utilization efficiency of 98% of its theoretical capacity, with a good cyclability over an extended range up to 40 cycles.