Synthesis of bowl-like mesoporous LiFePO4/C composites as cathode materials for lithium ion batteries

• Published in: Electrochimica acta Vol. 119; pp. 155 - 163
• Main Authors: Lv, Yi-Ju, Long, Yun-Fei, Su, Jing, Lv, Xiao-Yan, Wen, Yan-Xuan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10.02.2014
• Subjects: cathode; lithium iron phosphate; Lithium-ion battery; lithium iron phosphate; cathode; Lithium-ion battery
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2013.12.045

Mesoporous bowl-like LiFePO4/C composites were synthesized by a wet milling-spray drying-carbothermal reduction (WSC) using starch as the organic carbon source and reductive agent. The samples were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) analysis, cyclic voltammograms (CV), electrochemical impedance spectra (EIS) and galvanostatic charge–discharge testing. Most of the mesoporous bowl-like LiFePO4/C composites with particle size in the range 5–10μm, coated with evenly distributed carbon, were assembled by nanoparticles (<100nm), and had a mesoporous structure with the pore size of 13.30nm and a specific surface area of 29.40m2g−1. These delivered a discharge capability of 123mAhg−1 at 10 C, with no capacity loss after 100 cycles. The enhanced electrochemical performance was mainly ascribed to the improved ionic/electronic conductivity and structural stability arising from the interconnected mesoporous pores, carbon-coated nanoparticles and micro-sized structure.