Interfacial self-healing polymer electrolytes for long-cycle solid-state lithium-sulfur batteries

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Solid-state lithium-metal batteries offer higher energy density and safety.
• Challenges include limited ion conductivity, high interfacial resistance, and lithium dendrite growth.

Purpose of the Study:

• To design a self-healing polymer electrolyte for improved solid-state lithium-metal batteries.
• To reduce interfacial resistance and enhance interfacial contact.

Main Methods:

• Development of a poly(ether-urethane)-based solid-state polymer electrolyte with dynamic covalent disulfide and hydrogen bonds.
• Assembly of full cells with integrated electrodes/electrolytes.
• Utilizing ultrasound imaging to assess interfacial contact.

Main Results:

• The polymer electrolyte demonstrated excellent interfacial self-healing and maintained good interfacial contact.
• Li||Li symmetric cells achieved stable cycling over 6000 hours.
• Solid-state Li-S batteries showed a cycling life of 700 cycles at 0.3 C.
• Ultrasound imaging confirmed superior interfacial contact in the integrated structure compared to laminated structures.

Conclusions:

• The self-healing polymer electrolyte effectively reduces interfacial resistance and improves interfacial contact in solid-state lithium-metal batteries.
• This interfacial dual-integrated strategy offers a promising pathway for developing high-performance and safe solid-state batteries.