Fiber-Based Composite Separator with Stable Interface and High Ionic Transport Capacity for Lithium Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Traditional fiber-based separators face challenges like internal shorts and high resistance due to pore size and poor interfacial compatibility.
• These limitations negatively impact lithium battery performance and lifespan.

Purpose of the Study:

• To develop a novel fibrous composite separator with improved properties for lithium batteries.
• To enhance electrolyte wettability, reduce internal resistance, and improve interfacial compatibility and stability.

Main Methods:

• Coating a nonwoven fabric with a mixture of cross-linked poly(vinyl alcohol) and silica nanoparticles.
• Characterization of the separator's properties, including electrolyte wettability, ionic conductivity, and interfacial stability.
• Testing the performance of the separator in LiFePO4//Li batteries and Li//Li symmetrical cells.

Main Results:

• The prepared fibrous composite separator demonstrated excellent electrolyte wettability, low internal resistance, and superior interfacial compatibility and stability.
• It exhibited higher ionic conductivity and lithium-ion transference number compared to polyolefin separators.
• The separator effectively inhibited lithium dendrite growth and enabled stable cycling in battery cells.

Conclusions:

• The developed fibrous composite separator is a promising alternative to conventional lithium battery separators.
• Its scalable production and enhanced performance offer a competitive edge for commercial applications.
• This material advancement contributes to safer and more efficient lithium battery technology.