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To improve performance at higher rates, we developed a hydrothermal method to prepare carbon-coated monoclinic lithium vanadium phosphate (Li(3)V(2)(PO(4))(3)) powder to be used as a cathode material for Li-ion batteries. The structural, morphological and electrochemical properties were characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), and galvanostatic charge-discharge cycling. A superior cycle and rate behavior are demonstrated for Li(3)V(1.85)Sc(0.15)(PO(4))(3)/C and Li(2.96)Ca(0.02)V(2)(PO(4))(3)/C electrodes at charge-discharge current rates above 5C.

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Carbon-coated Li2MoO4 hexagonal hollow nanotubes were fabricated via a facile sol-gel method involving the solution synthesis of Li2MoO4 with subsequent annealing under an inert atmosphere to decompose the organic carbon source. To the best of our knowledge, this is the first report on the synthesis of Li2MoO4 nanotubes. More significantly, we have found that Li2MoO4 can be used as an anode material for lithium-ion batteries (LIBs). When evaluated as an anode material, the carbon-coated Li2MoO4 hollow nanotubes show an excellent electrochemical performance with a high reversible capacity (∼550 mA h g(-1)) after 23 cycles, good rate capability and cycling stability. Meanwhile, carbon-free Li2MoO4 sample, fabricated via a solid state reaction, was also prepared for comparison. The Li storage mechanism has been investigated in-detail by advanced XPS, in situ XRD and HRTEM.

A CoS/C nanocomposite is prepared using a solid-state reaction followed by a facile mechanical ball-milling treatment, with sucrose as the carbon source. The phases, morphologies, and detailed structures of the CoS/C nanocomposite are well-characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. When evaluated as an anode material for sodium-ion batteries, the CoS/C nanocomposite electrode displays a reversible capacity of ∼567 mA h g in the initial cycle and maintains a reversible capacity of ∼320 mA h g after 30 cycles, indicating a larger capacity and a stable cycling performance. For comparison, the electrochemical performances of CoS and CoS/C samples synthesized using the solid-state reaction are also displayed. The ex situ XRD and transmission electron microscopy tests demonstrate that CoS undergoes a conversion-type sodium storage mechanism.