Chloride-Ion-Enriched Solid Electrolyte Interphase with Rapid Na⁺ Migration toward High-Performance Sodium-Ion...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sodium-ion batteries (SIBs) are promising alternatives to lithium-ion batteries (LIBs) for large-scale energy storage.
• Alloy-type anode materials offer high capacity but suffer from volume expansion and poor ion kinetics, leading to degradation.
• Unstable solid electrolyte interphase (SEI) formation is a key challenge in SIB anode performance.

Purpose of the Study:

• To synthesize and evaluate chloride-ion-modulated bimetallic SnSb/C nanoparticle anode materials for SIBs.
• To address the challenges of volume changes, ion diffusion, and electrode degradation in SIB anodes.
• To enhance the electrochemical performance and structural stability of SIBs.

Main Methods:

• Synthesis of chloride-ion-modulated bimetallic SnSb/C nanoparticle anode materials.
• Characterization of the material structure, including bimetallic alloy formation and nanostructuring.
• Electrochemical testing to assess sodium ion insertion/extraction, diffusion kinetics, and SEI properties.

Main Results:

• The bimetallic SnSb alloy structure effectively buffers volume stresses, preventing particle fracture.
• Nanostructuring enhances active material utilization and shortens diffusion pathways for faster sodium ion transport.
• The carbonaceous matrix improves conductivity and structural stability, mitigating self-agglomeration.
• Chloride-ion interface modification results in a chloride-rich SEI, boosting overall battery performance.

Conclusions:

• Chloride-ion-modulated bimetallic SnSb/C nanoparticles represent a high-performance anode material for SIBs.
• The combined strategies of alloying, nanostructuring, carbon coating, and interface modification overcome key limitations in SIB anode design.
• This work provides a pathway for developing durable and efficient SIBs for energy storage applications.