Bi-Directional H-Bonding Modulated Soft/Hard Polyethylene Glycol-Polyaniline Coated Si-Anode for High-Performance...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Ultrahigh-capacity silicon anodes are critical for meeting the growing energy demands of electric transportation and energy storage.
• However, silicon anodes suffer from poor conductivity, slow ion diffusion, and significant volume changes during cycling, limiting their practical use.

Purpose of the Study:

• To develop a high-performance silicon anode by addressing its intrinsic limitations through a novel surface coating strategy.
• To enhance the electrochemical performance and cycling stability of silicon anodes for next-generation lithium-ion batteries.

Main Methods:

• Synthesized silicon nanoparticles coated with a dual layer of polyethylene glycol (PEG) and polyaniline (PANI) via hydrogen bonding.
• Investigated the structural integrity and electrochemical properties of the modified silicon anode (Si@PP).
• Evaluated the anode's performance in terms of initial Coulombic efficiency, specific capacity, capacity retention, and areal capacity.

Main Results:

• The Si@PP anode achieved a high initial Coulombic efficiency of 90.5%.
• It exhibited a stable capacity of 1871 mAh g^-1 after 100 cycles at 1 A g^-1 with 85.7% retention.
• A high areal capacity of 3.01 mAh cm^-2 was demonstrated after 100 cycles at 0.5 A g^-1.

Conclusions:

• The developed PEG/PANI coating effectively accommodates silicon's volume expansion and enhances both ionic and electronic conductivity.
• This scalable interface design offers a promising pathway for creating high-performance electrode materials for advanced lithium-ion batteries.