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Spinel LiVTiO 4 /C compound is prepared via a facile sol–gel method. The structure and morphology of LiVTiO 4 /C are investigated by X-ray diffraction (XRD), scanning electronmicroscopy (SEM), and transmission electron microscopy (TEM). The results indicate that the LiVTiO 4 /C has a carbon coating layer ranging between 2 and 3 nm. Besides, the existence of VO 2 improves the conductivity to some extent. The electrochemical properties of LiVTiO 4 /C as an anode material for lithium-ion battery are investigated for the first time. The synthesized LiVTiO 4 /C material exhibits a high charge capacity of 231.6 mA h g − 1 after 50 cycles at 0.02 A g − 1 , with a capacity retention ratio of 96.5%. The excellent reversible capacity and excellent cycling stability indicate that the LiVTiO 4 /C composite has a great potential application in lithium-ion battery. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of Ag doped lithium zinc titanate by a facile solid-state reaction method. [•] Electrochemical properties were tested in a charge/discharge voltage range of 0.05-3.0V (vs. Li/Li+). [•] Ag (x=0.15) doped lithium zinc titanate had good high rate capability and cycling stability. [ABSTRACT FROM AUTHOR]

For electrospun silicon/carbon nanofiber composites, the surface precipitation of silicon nanoparticles can cause poor cycle stability. To solve this, a carbon-coated silicon/carbon nanofiber (Si/C@C) composite with a 'sandwich' structure is constructed by hydrothermal reaction of glucose and an electrospun silicon/carbon nanofiber, followed by high-temperature carbonization. The effects of the thickness of the carbon coating layer and calcining temperature on the electrochemical performance are studied. The results showed that carbon is uniformly and continuously coated on the surface of the composite fibers, which avoid direct exposure of precipitated silicon on the surface of the nanofibers to the electrolyte, reduce the occurrence of side reactions and is conducive to the stable formation of SEI films. At the same time, the carbon shell inhibit the volume expansion of silicon to a certain extent and improve the conductivity of the composites. Consequently, the obtained Si/C@C exhibit good rate performance and cycle stability. With the optimised carbon coating thickness and calcination temperature, the obtained electrodes deliver a reversible capacity of 1120 and 683 mA h g-1 at a current density of 0.1 and 2 A g-1 respectively, and a specific capacity of 602 mAh∙g-1 at a current density of 1 A g-1 after 100 cycles, a capacity retention rate of 80%. The facilely synthesised Si/C@C composite shows potential applications in high-capacity silicon-based anode materials. [ABSTRACT FROM AUTHOR]

Li 2 MoO 4 modified Li 4 Ti 5 O 12 /C anode material has been synthesized by a ball-milling assisted rheological phase reaction method. The structures, morphologies and electrochemical properties of the as-prepared materials have been analyzed by different physical and electrochemical methods. The results show that the amorphous carbon is successfully coated on the surface of Li 4 Ti 5 O 12 nanoparticles with partial doping of Mo 6+ into the Li 4 Ti 5 O 12 structure. Electrochemical results indicate that Li 2 MoO 4 modified Li 4 Ti 5 O 12 /C samples deliver improved rate capability and decreased charge transfer resistance. Among the investigated samples, the one with 5 wt % Li 2 MoO 4 sample exhibits the optimal electrochemical properties and it shows a large capacity of 167.5 mAh g −1 at 1C rate, which is close to its theoretical capacity. Even at 10C, its charge capacity is up to 137.5 mAh g −1 with a high capacity retention of 92.5% after 200 cycles. The excellent electrochemical properties should be attributed to the improvement of electrochemical kinetics by the synergistic employment of reducing particle size, partial Mo 6+ doping and Li 2 MoO 4 /C modification. [ABSTRACT FROM AUTHOR]