A Light-Thin Chitosan Nanofiber Separator for High-Performance Lithium-Ion Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Growing demand for high-energy density and lightweight lithium-ion batteries (LIBs) for portable and wearable devices.
• The separator is a critical component influencing LIB performance, safety, and energy density.

Purpose of the Study:

• To fabricate a thin and porous chitosan nanofiber separator for advanced LIBs.
• To evaluate the performance of the chitosan separator in terms of electrolyte wettability, thermal stability, and cycling performance.

Main Methods:

• Fabrication of a chitosan nanofiber separator using a simple ethanol displacement method.
• Characterization of separator properties, including thickness, porosity, contact angle, and electrolyte uptake.
• Evaluation of LIB performance using the fabricated separator through cycling tests.

Main Results:

• A thin (half the thickness of Celgard2325) and porous chitosan nanofiber separator (CME15) was successfully fabricated.
• The CME15 separator demonstrated excellent electrolyte wettability (18° contact angle, 324% uptake) and thermal stability (up to 160 °C).
• LIBs utilizing the CME15 separator exhibited robust cycling performance, retaining 117 mAh g^-1 after 100 cycles at 1 C.

Conclusions:

• The developed chitosan nanofiber separator is a viable alternative for high-performance LIB applications.
• The separator's properties contribute to improved electrolyte interaction and battery longevity.
• This research provides a new perspective for utilizing chitosan-based materials in next-generation energy storage devices.