Synthesis of LiFePO4 / C Composite Particles by Gas–Solid Phase Reaction and Their Electrochemical Properties

Abstract

composite particles were prepared by a gas–solid phase reaction. The precursor particles for the olivine compounds were prepared by an intimate mixing of , , and and by calcination at in a atmosphere. Then, they were heated up to a predetermined temperature under a constant flow of hydrocarbon gas, which is a source of elemental carbon. The adjustment of the temperature enabled us to obtain the composite particles with few magnetic impurities (the spontaneous magnetization was less than 0.01 emu/g) as well as good electrical conductivity (the compact conductivity was higher than ). The composite particles, synthesized under the optimized condition, showed a reversible capacity greater than 150 mAh/g at a low current density of 0.1 C. Simultaneously, they also exhibited a superior performance in both cycle stability and rate capability.