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

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Graphite anodes in lithium-ion batteries (LIBs) face challenges with slow ion diffusion and capacity fade during high-rate cycling.
• Developing advanced anode materials is crucial for improving the performance of next-generation LIBs.

Purpose of the Study:

• To design and investigate a novel surface-lithiated porous graphite (LPG) anode for enhanced high-rate lithium-ion battery applications.
• To achieve a balance between high rate capability and long-term capacity retention in LIB anodes.

Main Methods:

• Fabrication of LPG through synergistic structural and interfacial modifications, introducing micron-scale pores.
• Characterization of the material's surface chemistry, including the formation of a Li3PO4-enriched solid electrolyte interface (SEI).
• Electrochemical testing to evaluate high-rate performance and cycling stability.

Main Results:

• LPG anodes demonstrated reduced Li+ diffusion distances and maintained a low specific surface area, ensuring over 90% initial Coulombic efficiency.
• The Li3PO4-enriched SEI effectively mitigated Li+ solvent interactions and improved desolvation kinetics.
• LPG anodes delivered a delithiated capacity of 327 mAh·g-1 at 50 C and retained 88.9% of initial capacity after 2000 cycles at 5 C.

Conclusions:

• The surface-lithiated porous graphite (LPG) anode presents a scalable and effective solution for high-rate lithium-ion batteries.
• The synergistic structural and interfacial design achieves a favorable balance between rate performance and capacity retention.
• Kilogram-scale production and soft-pack battery verification support the potential of LPG for commercial applications.