Poly(ethylene oxide)-Based Composite Electrolyte with Lithium-Doped High-Entropy Oxide Ceramic Enabled Robust...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Poly(ethylene oxide) (PEO) is widely used in solid polymer electrolytes for its Li+ transfer capabilities.
• However, PEO suffers from high crystallinity, low oxidation potential, and poor mechanical strength, limiting its use in solid-state batteries.

Purpose of the Study:

• To develop a composite solid electrolyte with improved properties for solid-state lithium metal batteries.
• To address the limitations of pure PEO by incorporating a lithium-doped high-entropy oxide (Li0.25HEO).

Main Methods:

• A composite solid electrolyte was synthesized by combining PEO with Li0.25HEO ceramic powder.
• The electrochemical properties, oxidation stability, and mechanical strength of the composite were evaluated.
• A solid-state lithium metal battery was assembled using the composite electrolyte and tested for performance.

Main Results:

• The Li0.25HEO component enhanced Li+ dissociation by capturing anionic groups via oxygen vacancies.
• Abundant Lewis acid sites in Li0.25HEO improved the oxidation potential window of PEO.
• The composite electrolyte exhibited reduced PEO crystallization and enhanced mechanical strength.
• The assembled solid-state lithium metal battery demonstrated high rate capacity and stable cycling.

Conclusions:

• The novel composite solid electrolyte offers superior properties for solid-state lithium metal batteries.
• This material shows significant potential for future development and application in advanced energy storage systems.