Tailor-Made Electrospun Multilayer Composite Polymer Electrolytes for High-Performance Lithium Polymer Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Developing stable and efficient electrolytes is crucial for next-generation batteries.
• Traditional liquid electrolytes pose safety risks due to flammability.
• Gel polymer electrolytes offer a safer alternative but often face challenges with ionic conductivity and mechanical stability.

Purpose of the Study:

• To create a novel multilayer composite polymer electrolyte with enhanced properties.
• To investigate the potential of electrospun fibrous membranes for battery applications.
• To evaluate the electrochemical performance of the developed gel polymer electrolyte.

Main Methods:

• Continuous electrospinning was used to fabricate multilayer composite membranes.
• The membranes consist of outer polyacrylonitrile (PAN) layers and an inner poly(vinyl acetate) (PVAc)/poly(methyl methacrylate) (PMMA)/poly(ethylene oxide) (PEO) fibrous layer.
• Gel polymer electrolytes (GPEs) were formed by incorporating a liquid electrolyte into the porous membranes.

Main Results:

• The composite membranes exhibited high porosity and excellent electrolyte uptake (450-510%).
• The GPEs demonstrated high room temperature ionic conductivity (up to 4.72 mS cm-1) and electrochemical stability (4.6 V vs. Li/Li+).
• Electrochemical tests with a LiFePO4 cathode showed a high initial discharge capacity (145 mAh g-1) and stable cycling performance.

Conclusions:

• The novel electrospun multilayer composite polymer electrolyte shows significant promise for high-performance and safe battery systems.
• The interconnected porous structure and high electrolyte uptake contribute to the enhanced ionic conductivity.
• The material's stability and capacity retention indicate its suitability for practical energy storage applications.