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Surface modified-LiV 3 O 8 cathode materials with Al 2 O 3 are successfully synthesized via a facile thermolysis process. The 0.5 wt.% Al 2 O 3 -coated LiV 3 O 8 exhibits an enhanced cyclic stability at various charge–discharge current densities. At a current density of 100 mA g −1 , it delivers an initial specific discharge capacity of 283.1 mAh g −1 between 2.0 and 4.0 V. Moreover, high capacities of 139.4 and 118.5 mAh g −1 are obtained at the 100th cycle at current densities of 2000 and 3000 mA g −1 , respectively. The improved electrochemical performance is attributed to the Al 2 O 3 coating, which can hinder the irreversible phase transformation and act as a protective layer to prevent the active material from direct contact with electrolyte. Furthermore, the formation of a Li–V–Al–O solid solution at the LiV 3 O 8 /Al 2 O 3 interface provides a fast Li + diffusion path which is of benefit to the electrochemical behaviors.

LiVO3 materials are synthesized by combustion method with oxalic acid as fuel. Owing to its relatively low crystallization and small particle size, the LiVO3 calcined at 450 °C for 2 h displays optimal electrochemical performances, delivering a high discharge capacity of 298.4 mAh g−1 and 262.5 mAh g−1 between 1.0 and 3.5 V at a current density of 50 mA g−1 and 500 mA g−1 respectively, and exhibiting good cyclic stability. In this work, the chemical diffusion coefficient of Li+ (DLi+) in the LiVO3 electrode is determined by electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT). The value calculated by EIS is in the range of 10−9–10−8 cm2 s−1, while it calculated by GITT is 10−9.5–10−8 cm2 s−1.

Cookies-shaped LiV 3 O 8 materials were successfully synthesized by a facile ethylene glycol-assisted sol–gel method. The LiV 3 O 8 compound fabricated at 550 °C delivers an initial specific discharge capacity of 255.2 mAh g − 1 between 2.0 and 4.0 V at a current density of 50 mA g − 1 , and possesses a capacity retention of 90.2% after 50 cycles and up to 85% at a current density of 120 mA g − 1 after 100 cycles. Furthermore, the compound with a proper particle size and high crystallinity also shows high electrochemical reversibility and structural stability, leading good rate capability. By analysis of inductively coupled plasma emission spectrometer (ICP), the cookies-like LiV 3 O 8 has very little dissolution of vanadium in the electrolyte after 100 cycles, indicating that the well-formed crystal can protect the structure damage to some degree during cycling.

LiVO3 is synthesized via a ball-milling route followed by a solid-state reaction at different temperatures. As cathode materials for lithium ion batteries, the electrochemical performances of LiVO3 are investigated by galvanostatic charge–discharge test and electrochemical impedance spectroscopy (EIS). The LiVO3 compound synthesized at 350 °C possesses the optimal performance, delivering an initial discharge capacity of 302.5 mAh g−1 between 1.0 V and 3.5 V at a current density of 50 mA g−1, and exhibiting a good cycling stability. Li-ion diffusion coefficient of 10−9.5–10−8 cm2 s−1 in the LiVO3 electrode is calculated by galvanostatic intermittent titration technique (GITT). The good performances can be attributed to its relatively low crystallization and small particle size.