Scalable synthesis of spherical graphite/ZnO composite anodes for high-performance lithium-ion batteries

Abstract

Reimagining graphite anodes through hybrid nano-architectures offers a powerful route to break the long-standing trade-off between capacity and stability in lithium-ion batteries. Here, we design a porous spherical graphite/ZnO (SG/ZnO) hybrid anode via a scalable one-pot hydrothermal synthesis combined with high-energy ball milling and mild annealing. The resulting hierarchical framework features robust SG–ZnO interfacial coupling, merging the conductivity and structural resilience of spherical graphite with the high capacity and surface reactivity of ZnO nanosheets. This architecture ensures efficient Li⁺ transport, accommodates volume changes, and suppresses mechanical degradation. The optimized SG/ZnO composite (SG-7/ZnO) delivers a reversible capacity of 423 mAh g⁻¹ at 160 mAh g⁻¹ over 150 cycles, significantly outperforming pristine SG and ZnO, owing to its excellent charge transport capability and enhanced electrochemical kinetics. This simple yet versatile strategy opens a new pathway for engineering high-performance oxide–carbon hybrids for next-generation rechargeable batteries.