The mechanical hybrid of V2O5 microspheres/graphene as an excellent cathode for lithium-ion batteries

Currently, lithium-ion batteries are widely used in many areas, but they are still limited by the lower cycle stability and energy density. The development of low-cost, environmentally friendly, high-performance methods for the synthesis of graphene-based cathode materials is critical for lithium-ion batteries. Here, V2O5 microspheres are synthesized by hydrothermal method. V2O5/graphene composite was constructed by wet ball milling. The nanometer-sized V2O5 microspheres were well embedded and evenly dispersed into the flexible graphene sheets. Microsphere structure of V2O5 reduces the ion transport distance, while the presence of the graphene component enhances the conduction of electrons in V2O5@G composites by partially exposing them to the surface of the composites. This study suggests that metal oxide electrodes in integration with graphene can address the poor cycling issues of electrode materials that suffer from low electronic and ionic conductivities. In LIBs, the V2O5@G cathode exhibits a discharge capacity of 313.65 mAh g(-1) at 150 mA g(-1) (1/2 C) with high specific capacity, and more than 150 mAh g(-1) at 3A g(-1) (10 C). After 500 cycles at 150 mA g(-1), excellent cycling stability is still maintained. A practical strategy for the development of vanadium-based cathode materials with great promising potential in the field of lithium-based energy storage is provided by this work.

Automated summary

In this study, V2O5 microspheres were synthesized using a hydrothermal method, and V2O5/graphene composites were formed by wet ball milling. The results showed that the composites exhibited high specific capacity, excellent cycling stability, and addressed the poor cycling issues of electrode materials.