Synergistic Pore Architecture and Surface Lithiation Enable Li₃PO₄-Dominated Interphases for Ultrahigh-Rate Graphite Anodes.

Abstract

Designing high-rate anodes for lithium-ion batteries (LIBs) remains a critical challenge due to the sluggish ion dynamics and capacity degradation of graphite-based materials under high-rate cycling. Here, we present a surface-lithiated porous graphite (LPG) anode designed through synergistic structural and interfacial modifications. Micron-scale pores introduced on graphite basal planes reduce Li⁺ diffusion distance while maintaining a low specific surface area (≤ 2 m²·g^-1), ensuring an initial Coulombic efficiency exceeding 90%. Surface lithium-containing groups are identified as a key factor in inducing the formation of a Li₃PO₄-enriched solid electrolyte interface (SEI), which effectively mitigates Li⁺-solvent interactions and enhances desolvation kinetics. As a result, LPG anodes exhibit good high-rate capabilities, delivering a delithiated capacity of 327 mAh·g^-1 at 50 C and retaining 88.9% initial capacity after 2000 cycles at 5 C. With kilogram-scale production and soft-pack battery verification, this strategy positions LPG as a scalable, high-rate anode solution for next-generation LIBs, achieving a good balance between rate performance and capacity retention. Surface-lithiated porous graphite achieves a good balance in balancing rate performance and capacity retention for lithium-ion batteries.