Graphene Oxide Induced Surface Modification for Functional Separators in Lithium Secondary Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Chemical Engineering

Background:

• Advanced lithium-ion batteries require functional separators beyond basic ionic conduction and electronic insulation for enhanced safety and power density.
• Conventional separators exhibit hydrophobic wetting, hindering the application of polar, water-based slurries for functional material deposition.
• This limitation restricts the use of diverse functional materials dispersible in polar solvents for battery development.

Purpose of the Study:

• To develop a simple, eco-friendly surface modification method for conventional battery separators.
• To enhance the wetting properties of separators for broader functional material compatibility.
• To demonstrate the fabrication of advanced functional separators for high-performance secondary batteries.

Main Methods:

• Surface modification of conventional separators using solution-based coating of graphene oxide.
• Tuning surface wetting properties by altering separator morphology and surface polarity.
• Characterization of modified separators for wetting behavior and lithium-ion transport.

Main Results:

• Achieved large-scale tunable surface wetting properties on conventional separators.
• Demonstrated superior wetting capabilities on the graphene oxide-modified surfaces.
• Successfully fabricated a functional separator applicable to lithium metal secondary batteries without significant degradation of ion transport.

Conclusions:

• The proposed graphene oxide surface modification is a simple and effective method for creating advanced functional separators.
• This technique overcomes limitations associated with hydrophobic separator surfaces and polar slurries.
• The approach facilitates the development of high-performance, safe secondary batteries through versatile functionalization.