Enhancing CA-based separators with thermo-responsive ionic liquids: A path to eco-friendly membrane production and...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Developing advanced battery separators is crucial for enhancing lithium-ion battery performance and safety.
• Environmentally friendly materials are increasingly sought after in battery manufacturing to reduce ecological impact.
• Cellulose acetate (CA) is a promising biodegradable polymer for battery separator applications.

Purpose of the Study:

• To synthesize and characterize a temperature-responsive ionic liquid, [N4444][SS].
• To incorporate [N4444][SS] into a cellulose acetate (CA) matrix for creating a novel battery separator.
• To evaluate the performance and structural properties of the developed CA/[N4444][SS] battery separator for lithium-ion batteries.

Main Methods:

• Synthesis of [N4444][SS] and its incorporation into a CA-based membrane.
• Fabrication of battery separators with varying drying temperatures (25°C and 50°C).
• Characterization using techniques such as TGA, DSC, FT-IR, and analysis of water flux and Gurley value.

Main Results:

• The CA/[N4444][SS] membrane dried at 50°C exhibited increased thickness, smaller average pore size, and an asymmetric internal structure.
• This membrane showed significantly higher water flux and a lower Gurley value, indicating reduced tortuosity and pore resistance.
• [N4444][SS] was confirmed to remain within the CA matrix through coordinative bonding, as evidenced by thermal and spectroscopic analyses.

Conclusions:

• The developed CA/[N4444][SS] battery separator demonstrates enhanced Li-ion transport properties and conductivity.
• The asymmetric structure and optimized pore characteristics contribute to improved separator performance.
• The recyclability of the ionic liquid and the use of CA promote a more sustainable and environmentally friendly battery technology.