Lithiophilic vanadium oxide coated three-dimensional carbon network design towards stable lithium metal anode

The uncontrollable lithium dendrite growth and large volume changes during battery charge/discharge process lead to safety issues and performance degradation problems in lithium metal-based anode. To tackle these issues, an effective solution is to achieve uniform lithium deposition with buffering structure design of the anode. Herein, a high-performance Li host anode composite is developed by coating lithiophilic vanadium oxide onto three-dimensionally structured N-doped CNT rooted on carbon nanotube film (VO2-CNT/CNF). The porous structure of CNT/CNF provides a good buffering effect for the volume change of lithium metal anode during charging and discharging process. At the same time, the N-doped CNTs rooted on CNF fibers provide sufficient lithium nucleation sites for lithium deposition that reduce the regional current density preventing the growth of lithium dendrites. Attributed to these beneficial features, the VO2-CNT/CNF@Li anode exhibits a dendrite-free morphology and excellent cycling performance in lithium-sulfur batteries. The S/C || VO2-CNT/CNF@Li bat-tery also shows good cycling stability at 1 C, and the capacity decay rate per cycle after 500 cycles is less than 0.05%.

Automated summary

To address the safety and performance issues in lithium metal-based anode, a high-performance Li host anode composite is developed by coating lithiophilic vanadium oxide onto three-dimensionally structured N-doped CNT rooted on carbon nanotube film. This composite anode exhibits a dendrite-free morphology and excellent cycling performance in lithium-sulfur batteries, thanks to the buffering effect of the porous structure and the sufficient lithium nucleation sites provided by the N-doped CNTs. The cycling stability of the battery is also demonstrated with a capacity decay rate per cycle less than 0.05% after 500 cycles.