Impedance and structural studies on plasticized PCL-LiSO3CF3-SiO2 polymer electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Developing safe and efficient electrolytes is crucial for advanced energy storage devices.
• Biodegradable polymers offer a sustainable alternative to conventional electrolyte materials.
• Enhancing ionic conductivity in polymer electrolytes is a key challenge.

Purpose of the Study:

• To synthesize and characterize novel plasticized polymer electrolytes based on polycaprolactone (PCL).
• To investigate the effect of ethylene carbonate (EC) plasticizer, lithium triflate (LiSO3CF3) salt, and silicon dioxide (SiO2) nanoparticles on electrolyte properties.
• To correlate the structural properties with the ionic conductivity of the developed electrolytes.

Main Methods:

• Solution casting technique for electrolyte preparation.
• Electrochemical Impedance Spectroscopy (EIS) for ionic conductivity measurements.
• X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy for structural analysis.

Main Results:

• Achieved a maximum ionic conductivity of 4.30 x 10^-3 S cm^-1 at ambient temperature.
• Demonstrated a direct relationship between ionic conductivity and the amorphous phase content of the electrolytes.
• Characterized structural and complex formation using XRD and FTIR.

Conclusions:

• The plasticized PCL-based polymer electrolytes exhibit significant ionic conductivity.
• The addition of EC, LiSO3CF3, and SiO2 nanoparticles effectively enhances electrolyte performance.
• The amorphous phase content, confirmed by XRD and FTIR, is critical for high ionic conductivity, indicating potential for battery applications.