Disulfide Metathesis-Assisted Lithium-Ion Conduction for PEO-Based Polymer Electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Disulfide metathesis is a dynamic exchange strategy for self-healing polymer electrolytes (PEs).
• Enhancing ionic conductivity in PEs with dynamic covalent bonds is often overlooked.
• Oligo(ethylene oxide)-based additives with disulfide bonds (S-S additives) were synthesized.

Purpose of the Study:

• To investigate the impact of disulfide metathesis on the ionic conductivity of polymer electrolytes.
• To explore the use of S-S additives for improving Li+ conduction in PEs.
• To evaluate the performance of these PEs in lithium-metal batteries (LMBs).

Main Methods:

• Synthesis of an oligo(ethylene oxide)-based additive containing a disulfide bond via Michael addition.
• Incorporation of the S-S additive into polymer electrolytes.
• Measurement of ionic conductivity and Li+ transference number.
• Assembly and testing of lithium-metal batteries.

Main Results:

• The S-S additive facilitated rapid Li+ migration due to disulfide bond exchange.
• The prepared PEs achieved a high room temperature ionic conductivity of 1.24 × 10^-4 S cm^-1.
• Disulfide-containing PEs showed a high Li+ transference number (0.54).

Conclusions:

• Disulfide metathesis is a feasible strategy for enhancing ionic conductivity in PEs.
• The developed PEs demonstrate promising potential for next-generation lithium-metal batteries.
• The S-S additive contributes to stable battery cycle performance.