Role of deviation from Li stoichiometry in synthesis of LiFePO4 cathodematerial

Olivine-structured LiFePO4 was successfully synthesized by co-precipitation method as thecathode material for Li-ion battery application. In this study, deviation from nominalstoichiometry of LiFePO4 and its effects on the final phase composition and powder particlemorphology have been investigated using X-ray diffraction (XRD) and high resolution scanningelectron microscopy (HRSEM), respectively. The XRD results revealed that the molarcomposition of Li : Fe : PO4 = 1.25 : 1 : 1 in the precipitation stage is the proper stoichiometryfor achieving single phase LiFePO4 with orthorhombic crystal structure after calcination at 700˚Cunder reductive atmosphere. Scanning electron microscopy studies confirmed formation of ultrafinespherical particles of LiFePO4 phase for the above sample.

Keywords:

Lithium-ion battery , Cathode materials , LiFePO4 , Sarcopside