MWCNT synergy for boosting the electrochemical kinetics of V2O5 cathode for lithium-ion batteries

Abstract

Nanomaterial synergy in a hybrid system offers an unprecedented opportunity for the development of high-performance energy storage devices. In this work, to intrinsically boost the lithium storage properties of layered structure V₂O₅, hybrid systems involving V₂O₅/MWCNTs are synthesized and investigated as cathode materials for lithium-ion batteries. It is found that the V₂O₅/MWCNT electrode demonstrates a higher initial discharge capacity of 329 mA h g⁻¹ with a coulombic efficiency of 97% at 0.1C between 1.5 V and 4.2 V versus Li/Li⁺. The developed electrode delivers a reversible capacity of 217 mA h g⁻¹ at 0.1C after 100 cycles and 106 mA h g⁻¹ at 1C after 500 cycles with a capacity retention rate of 84.7% and 80.9% respectively. In addition, electrochemical impedance spectroscopy (EIS) and density functional theory (DFT) confirm the enhanced kinetics of the V₂O₅/MWCNT electrode. The improved and efficient performance of the electrode is due to the synergy between V₂O₅ and MWCNTs, which facilitates a convenient path for fast Li⁺ ion diffusion and reduces the strain generated during the charge/discharge process. This work suggests that the reported V₂O₅/MWCNT hybrid system can be utilized as a cathode for the construction of LIBs with high-rate capability and long cycle life.