Spherulite-packed polymer electrolytes with high ion selectivity for stable lithium-sulfur battery performance

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Lithium-sulfur (Li-S) batteries offer high theoretical energy density but suffer from poor cycle life due to polysulfide shuttling.
• Developing stable solid-state electrolytes is crucial for overcoming Li-S battery limitations.

Purpose of the Study:

• To engineer a polymer electrolyte with a synergistic barrier against polysulfide diffusion.
• To enhance the long-term cycling stability and performance of lithium-sulfur batteries.

Main Methods:

• Fabrication of a spherulite-packed polymer electrolyte via controlled phase separation using TEGDME.
• In situ polymerization of AMPSLi within the polymer matrix.
• Electrochemical testing of the prepared electrolyte in Li-S cells.

Main Results:

• The unique spherulite structure effectively suppressed polysulfide migration.
• Achieved a high reversible capacity of 705 mAh g^-1 after 300 cycles at 1C.
• Demonstrated significantly improved long-term cycling stability.

Conclusions:

• The developed polymer electrolyte provides a robust physical-electrostatic barrier against polysulfides.
• This approach offers a promising strategy for advancing high-performance and stable lithium-sulfur batteries.