Synthesis and electrochemical performance of Li2FeSiO4/carbon/carbon nano-tubes for lithium ion battery

Li2FeSiO4/carbon/carbon nano-tubes (Li2FeSiO4/C/CNTs) and Li2FeSiO4/carbon (Li2FeSiO4/C) composites were synthesized by a traditional solid-state reaction method and characterized comparatively by X-ray diffraction, scanning electron microscopy, BET surface area measurement, galvanostatic charge–discharge and AC impedance spectroscopy, respectively. The results revealed that the Li2FeSiO4/C/CNT composite exhibited much better rate performance in comparison with the Li2FeSiO4/C composite. At 0.2 C, 5 C and 10 C, the former composite electrode delivered a discharge capacity of 142 mAh g−1, 95 mAh g−1, 80 mAh g−1, respectively, and after 100 cycles at 1 C, the discharge capacity remained 95.1% of its initial value.