Coupling a 3D Lithophilic Skeleton with a Fluorine-Enriched Interface to Enable Stable Lithium Metal Anode

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal anodes are crucial for high-energy-density batteries but suffer from dendrite growth and unstable solid electrolyte interfaces (SEI).
• These issues limit the commercial viability of lithium metal batteries.

Purpose of the Study:

• To develop a composite lithium metal anode that suppresses dendrite formation and improves the stability of the SEI layer.
• To enhance the electrochemical performance and cycling stability of lithium metal batteries.

Main Methods:

• Fabrication of a fluorine-enriched nitrogen-doped hollow carbon spheres decorated carbon fibers (FNCS@CF) skeleton.
• Electrochemical characterization of the FNCS@CF composite as a lithium metal anode.
• Assembly and testing of a full cell using the developed anode.

Main Results:

• The FNCS@CF skeleton facilitates uniform lithium deposition by reducing the nucleation barrier through lithiophilic nitrogen sites.
• It promotes the in situ formation of a robust, LiF-enriched SEI layer.
• Demonstrated ultrahigh Coulombic efficiency (99.6% over 240 cycles), long-term cyclability (1300 h), and low deposition overpotential (10 mV).
• A full cell (FNCS@CF-Li|NCM) showed excellent stability under practical conditions (low N/P ratio, lean electrolyte).

Conclusions:

• The FNCS@CF composite effectively addresses the challenges of lithium dendrite growth and SEI instability.
• This material offers a promising solution for developing durable and safe next-generation high-energy-density rechargeable batteries.