Molecular Coupling Strategy Achieving In Situ Synthesis of Agglomeration-Free Solid Composite Electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Solid composite electrolytes (SCEs) combine inorganic and polymer properties for practical use.
• Poor interfacial stability in SCEs causes particle agglomeration and hinders lithium-ion (Li+) transport.

Purpose of the Study:

• To create an agglomeration-free solid composite electrolyte with improved interfacial compatibility.
• To enhance Li+ conductivity, transference number, and oxidation potential for advanced batteries.

Main Methods:

• In situ solidification using triethoxyvinylsilane (VTEO) to chemically link poly(vinylene carbonate) (PVC) and montmorillonite (MMT).
• Characterization of the synthesized PVC-s-MMT solid composite electrolytes.
• Fabrication and testing of Li/PVC-s-MMT/LiFePO4 battery cells.
• Density Functional Theory (DFT) calculations to analyze ion transport pathways.

Main Results:

• Achieved Li+ conductivity of 0.4 mS cm-1 at 25 °C.
• Enhanced Li+ transference number to 0.74 and oxidation potential to 5.2 V.
• Demonstrated excellent cycling stability (>99.5% after 600 cycles) in LiFePO4 cells at room temperature.

Conclusions:

• The VTEO-mediated in situ method effectively prevents agglomeration and enhances interfacial compatibility in SCEs.
• The developed PVC-s-MMT electrolytes offer superior electrochemical performance suitable for next-generation lithium-ion batteries.
• This synthesis approach is compatible with existing industrial battery manufacturing processes.