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LiMn2O4 nanoparticles were successfully prepared using suitable dosage carbon nanotubles (CNTs) as a fuel through multiphase combustion synthesis. The effects of CNTs on the structure and electrochemical performance of LiMn2O4 were investigated. Rate performance test demonstrates that CNTs dosage greatly affect the electrochemical behaviour of LiMn2O4 and LiMn2O4 prepared by choosing suitable CNTs dosage (7%) as a fuel (C7%-LMO) shows high rate charge–discharge capability. X-ray diffraction results indicate that C7%-LMO has the smallest distortion degree in the crystal, compared to LiMn2O4 prepared without CNTs (C0%-LMO) and LiMn2O4 prepared with 10% CNTs (C10%-LMO). SEM results reveal that the average particle size of C7%-LMO is about 100 nm, which is the smallest among the three samples (C0%-LMO, C7%-LMO and C10%-LMO). This unique microscopic features guarantee C7%-LMO possesses the highest discharge capacity, the best cycling performance and the lowest charge transfer resistance among the three samples. [ABSTRACT FROM AUTHOR]

The Li3V2(PO4)3/C cathode materials for lithium ion batteries are synthesised by sol-gel method using three different compounds (citric acid, glycine and oxalic acid) as the chelating agents. The effects of chelating agents on the physical properties and electrochemical performances of the Li3V2(PO4)3/C composites are investigated by thermogravimetric analysis, infrared spectrometry, X-ray diffraction, scanning electron microscopy and various electrochemical techniques. The results show that the electrochemical properties of Li3V2(PO4)3/C prepared using citric acid as chelating agent are better. In the voltage range of 3.0-4.3 V (versus Li+/Li), the citric acid chelated Li3V2(PO4)3 displays large reversible capacity with an initial discharge capacity of 126.7 mAh g− 1 at 0.5°C, and 91.3% of the initial discharge capacity is retained after 50 charge-discharge cycling. [ABSTRACT FROM AUTHOR]