Monodisperse porous LiFePO4/C microspheres derived by microwave-assisted hydrothermal process combined with carbothermal reduction for high power lithium-ion batteries

A microwave-assisted hydrothermal approach combined with carbothermal reduction has been developed to synthesize monodisperse porous LiFePO 4 /C microspheres , which possess the diameter range of 1.0–1.5 μm, high tap density of ∼1.3 g cm −3 , and mesoporous characteristic with Brunauer–Emmett–Teller (BET) surface area of 30.6 m 2  g −1 . The obtained microspheres show meatball-like morphology aggregated by the carbon-coated LiFePO 4 nanoparticles . The electrochemical impedance spectra (EIS) results indicate that carbon coating can effectively enhance both of the electronic and ionic conductivities for LiFePO 4 /C microspheres. The Li-ion diffusion coefficient of the LiFePO 4 /C microspheres calculated from the cyclic voltammetry (CV) curves is ∼6.25 × 10 −9  cm 2  s −1 . The electrochemical performance can achieve about 100 and 90 mAh g −1 at 5C and 10C charge/discharge rates, respectively. As cathode material , the as-prepared LiFePO 4 /C microspheres show excellent rate capability and cycle stability, promising for high power lithium-ion batteries.