Tunable Networks from Thiolene Chemistry for Lithium Ion Conduction

Area of Science:

• Polymer Chemistry
• Materials Science
• Electrochemistry

Background:

• Polymer electrolytes are crucial for advanced battery technologies.
• Developing solid-state electrolytes with high ionic conductivity and good mechanical properties remains a challenge.

Purpose of the Study:

• To synthesize and characterize robust, tunable polymer networks for lithium-ion conduction.
• To investigate the effect of lithium bis(trifluoromethane sulfonyl imide) (LiTFSI) loading on the properties of poly(ethylene glycol) (PEG) and PEG-polydimethylsiloxane (PDMS) networks.
• To explore the potential of these materials as solid-state electrolytes.

Main Methods:

• Synthesis of end-functionalized PEG and PDMS polymers.
• Cross-linking polymers using a tetra-functional thiol via thiol-ene reaction.
• Loading networks with varying concentrations of LiTFSI.
• Characterization of thermal, mechanical, and ion conductivity properties using techniques like impedance spectroscopy.

Main Results:

• Robust and tunable PEG and PEG-PDMS networks were successfully created.
• The networks maintained rubber-like characteristics and thermal stability (30-90 °C) even at high salt loadings.
• The PEG network with the highest LiTFSI loading achieved an ion conductivity of 6.7 × 10^-4 S cm^-1 at 30 °C.

Conclusions:

• The developed polymer networks offer a promising route for optimizing lithium ion conduction.
• The combination of tunable mechanical properties and ionic conductivity makes these materials suitable for solid-state electrolytes.
• This study demonstrates a versatile platform for designing advanced polymer electrolytes for energy storage applications.