Liquid Metal-Induced Self-Healing Interface and 3D Porous Configuration Enable a High-Performance Si/Carbon Anode for...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Gallium-based liquid metals (LMs) offer dynamic adaptability and conductivity for electrode materials.
• Conventional LM fabrication yields large particles, hindering lithium-ion diffusion.
• Silicon anodes face challenges with volume expansion and structural degradation during cycling.

Purpose of the Study:

• To design a novel silicon/carbon composite integrated with gallium-indium liquid metals (GaIn-Si@PCC) for advanced battery anodes.
• To address poor lithium-ion diffusivity and structural instability in silicon-based anodes.
• To leverage the unique properties of LMs for enhanced electrochemical performance.

Main Methods:

• Fabrication of a 3D porous silicon/carbon composite using a dual-carbon precursor, freeze-drying, and thermal reduction.
• Encapsulation of silicon nanoparticles within a porous carbon framework decorated with GaIn LMs.
• Utilizing theoretical calculations to analyze ion adsorption-diffusion and electronic structure.

Main Results:

• The GaIn phase effectively alleviates lithiation stress through plastic deformation and self-healing.
• A continuous conductive network and optimized Li+ transport were established.
• The GaIn-Si@PCC anode demonstrated high initial Coulombic efficiency (87.3%) and excellent cycling stability (1595.4 mAh g-1 after 200 cycles).
• A full cell with an NCM811 cathode retained 86.8% capacity after 100 cycles.

Conclusions:

• The developed GaIn-Si@PCC composite offers a multiscale design strategy for high-performance silicon anodes.
• Dynamic stress management and ion regulation by GaIn LMs significantly improve battery performance.
• This approach provides a pathway for creating stable and efficient silicon-based energy storage systems.