A Fully Amorphous, Dynamic Cross-Linked Polymer Electrolyte for Lithium-Sulfur Batteries Operating at...

Area of Science:

• Electrochemistry
• Materials Science
• Polymer Science

Background:

• Solid-state lithium-sulfur batteries offer safe, high-energy storage for electric transportation.
• Current crystalline polymer electrolytes limit ion mobility, hindering subzero temperature operation.
• Liquid plasticizers improve conductivity but compromise mechanical and interfacial stability.

Purpose of the Study:

• To develop a polymer electrolyte for solid-state lithium-sulfur batteries capable of subzero temperature operation.
• To enhance Li-ion conductivity, mechanical strength, and interfacial stability in polymer electrolytes.

Main Methods:

• Introduction of a spherical hyperbranched solid polymer plasticizer into a Li+-conductive linear polymer matrix.
• Formation of an integrated dynamic cross-linked polymer network.
• Preparation of a quasi-solid polymer electrolyte with >90% solid mass content.

Main Results:

• The cross-linked polymer network maintained an amorphous state across a wide temperature range, including subzero.
• The quasi-solid electrolyte exhibited fast Li+ conduction at low temperatures, high mechanical strength, and stable interfaces.
• Solid-state lithium-sulfur batteries demonstrated high reversible capacity and extended cycle life at temperatures down to -10°C.

Conclusions:

• The novel dynamic cross-linked polymer electrolyte enables efficient solid-state lithium-sulfur battery operation under complex environmental conditions.
• This technology addresses the limitations of traditional polymer electrolytes for low-temperature energy storage applications.