Structure-Tunable Fluorinated Polyester Electrolytes with Enhanced Interfacial Stability for Recyclable Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Polyesters are gaining attention as sustainable solid polymer electrolytes for solid-state lithium metal batteries (SSLMBs).
• Tuning polyester structure is key to optimizing performance in battery applications.

Purpose of the Study:

• To investigate the impact of systematic fluorination on polyester structure and ionic conductivity.
• To develop a cost-effective and sustainable recycling method for fluorinated polyester electrolytes.

Main Methods:

• Fabrication of 18 polyester types with varied carbon chain lengths and fluorination positions.
• Experimental and theoretical studies to analyze ionic conductivity, crystallinity, and interfacial stability.
• Development and evaluation of a solvent-based recycling process.

Main Results:

• Fluorination at the coordinating segment enhanced ionic conductivity by reducing crystallinity.
• Fluorination at the flexible segment improved lithium-ion transference number by creating homogeneous coordinating sites.
• Optimized polyesters demonstrated excellent interfacial stability with lithium metal, forming a LiF-rich interphase.
• A solvent-based recycling route achieved high recovery yields and environmental benefits.

Conclusions:

• Molecular design of fluorinated polyesters offers a versatile strategy for enhancing SSLMB performance.
• The developed closed-loop recovery strategy promotes cost-effectiveness and sustainability.
• These advancements pave the way for practical applications of high-energy and sustainable SSLMBs.