Mesoporous LiFePO4 microspheres for rechargeable lithium-ion batteries

A series of mesoporous LiFePO4/C microspheres have been successfully synthesized via a hydrothermal process using citric acid as chelating agent and reductant. The growth evolution process of the precursor is systematically investigated based on the time-dependent experiments. Pure mesoporous LiFePO4 microspheres are obtained with a diameter of similar to 2 mu M, which are composed of numerous compact nanoparticles (similar to 200 nm). These microspheric LiFePO4 shows high tap density (1.35 g cm(-3)) and large Brunauer-Emmett-Teller (BET) surface area (20.992 m(2) g(-1)), which favor the electrochemical properties. The initial discharge capacity of LiFePO4/C microspheres is 163.8 mAh g(-1) at 0.1 C rate, corresponding to 96.4% of the theoretical capacity of LiFePO4 (170 mAh g(-1)). The material also shows excellent high rate capability (120.3 mAh g(-1), 10C), and cycling stability (a capacity retention of 98.1% at 0.5 C rate after 200 cycles). (C) 2013 Elsevier Ltd. All rights reserved.