Core-Shell Coating Silicon Anode Interfaces with Coordination Complex for Stable Lithium-Ion Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Silicon (Si)-based anodes offer high theoretical capacity for lithium-ion batteries (LIBs).
• Poor cycling stability and volume expansion hinder Si anode practical application.
• Developing stable electrode materials is crucial for advanced energy storage.

Purpose of the Study:

• To improve the electrochemical performance and cycling stability of Si-based anodes.
• To create a conformal, conductive coating on Si nanoparticles.
• To enable facile and large-scale production of durable Si anodes for LIBs.

Main Methods:

• In situ core-shell coating of commercial Si nanoparticles using polypyrrole-Fe coordination complex.
• Modification via hydrogen bonding between functional groups of the complex and Si nanoparticles.
• Electrochemical testing to evaluate capacity, rate capability, and cycling performance.

Main Results:

• The polypyrrole-Fe coating provided electrical connectivity and a stable solid-electrolyte-interface (SEI).
• Modified Si anodes demonstrated high reversible capacity (3567 mAh/g at 0.3 A/g).
• Excellent cycling stability was achieved, retaining 1500 mAh/g after 800 cycles at 1.2 A/g.

Conclusions:

• The core-shell coating strategy effectively enhances Si anode performance for LIBs.
• This method offers a promising route for scalable production of durable Si anodes.
• The technology has potential applications in renewable energy storage systems.