One-step dual process strategy for holey graphite towards scalable and stable lithium-ion battery anodes

Abstract

Our research demonstrates a one-step dual-process acid treatment approach for modifying graphite, which increases its interlayer distance and generates nanoscale holes, thereby effectively shortening the lithium-ion diffusion pathway without the need for heteroatom doping. Compared with pristine graphite (PG), the expanded holey graphite (EG) produced by this process achieves significantly enhanced electrochemical performance while maintaining structural integrity. The EG shows excellent electrochemical performance, reaching a specific capacity of 179.45 mAh g⁻¹ and retaining 89.3% of its capacity after 300 cycles in a full pouch cell combined with a commercial NMC523 cathode. High coulombic efficiency (approximately 93.8%) and improved cycling stability confirm the durability of the etched graphite. Beyond mere performance considerations, the study elucidates the degradation mechanisms inherent in commercial lithium-ion batteries (LIBs), thereby offering dependable guidance for electrode surface engineering and the optimization of cycling protocols. With this scalable and impurity-free approach to modification, purified etched graphite emerges as a promising candidate for next-generation LIB anodes, satisfying the high energy requirements and durability necessary for electric vehicles and advanced energy storage systems.