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In this study, lithium terephthalate by solvothermal method with low energy consumption and simple preparation process were synthesized. To obtain the lithium terephthalate with best electrochemical properties, the effects of different organic solvents, reaction temperature and lithium source were investigated and compared. The electrochemical performance of lithium terephthalate prepared from various processing methods as lithium ion battery was furtherly analyzed and discussed. The compositions lithium terephthalate of were confirmed by XRD and FTIR, the morphologies were observed by SEM, and the electrochemical properties were analyzed by cycle charge-discharge tests. The results show that the first discharge capacity of the battery prepared by lithium hydroxide in DMF at a reaction temperature of 175 °C presented the best performance, reaching a maximum capacity of 235/74 mA⋅h/g. [ABSTRACT FROM AUTHOR]

• Glass with a high vanadium content improved the migration efficiency of Li+. • Adding Fe 2 O 3 stabilized the structure and increased the contents of V3+ and V4+. • The cathode has the outstanding specific capacity and high-current response. Among new lithium-ion battery cathode materials, amorphous materials show unique advantages and vanadium-based materials are potential electrode materials. In our study, the vanadium-based Li 2 O-V 2 O 5 -B 2 O 3 glassy state electrode materials with high vanadium contents were prepared in air by the melt-quenching method. The structures and electrochemical performances of glass materials were investigated by various characterization methods. The Li 2 O-V 2 O 5 -B 2 O glass were mainly connected with VO 4 and BO 3 structural units to form a disordered network structure. The first discharge capacity of 20Li 2 O-60 V 2 O 5 -20B 2 O 3 glass cathode material reached 168.6 mAh/g at a current density of 100 mA/g. The conversion of V3+/V4+ and V4+/V5+ mainly occurred in the charge and discharge cycles. When 10% of B 2 O 3 was replaced by Fe 2 O 3 , the compactness and stability of the material were improved. Furthermore, with the addition of Fe 2 O 3 , the concentrations of low-valence V4+, V3+ and Fe2+ ions increased, thus contributing to the electrochemical performance. The specific capacity of 20Li 2 O-60V 2 O 5 -10B 2 O 3 -10Fe 2 O 3 cathode material increased significantly and the first discharge capacity was as high as 306.2 mA h/g at a current density of 100 mA/g. However, the specific capacity respectively decreased to 239 mA h/g in the second cycle and 120.3 mA h/g after 100 cycles. The study on vanadium-based glass cathode materials provided a new idea for the investigation of novel cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]