Constructing Matching Interfaces by Amorphous Engineering for Enhanced Lithium Ion Transport in Quasi-Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Quasi-solid-state lithium-iodine (Li-I2) batteries offer high theoretical capacity and safety but suffer from poor interface bonding in composite electrolytes, hindering Li+ migration.
• Inadequate bonding between crystalline fillers and polymer skeletons leads to high interface energy and slow Li+ dynamics, limiting battery performance.

Purpose of the Study:

• To design a continuous interface solid electrolyte for improved Li-I2 batteries.
• To enhance Li+ migration and polyiodide confinement through atomic structure rearrangement and amorphous engineering.
• To investigate the mechanism of coupled interfaces for high-performance composite solid electrolytes.

Main Methods:

• Atomic structure rearrangement of metal-organic frameworks (MOFs) to create interface coupling with aramid fiber.
• Experimental testing and theoretical calculations to analyze Li+ migration and polyiodide confinement.
• Fabrication and electrochemical performance evaluation of the novel composite solid electrolyte in Li-I2 batteries.

Main Results:

• The designed electrolyte demonstrated enhanced Li+ migration and effective polyiodide confinement.
• Li-I2 batteries achieved a high capacity of 170.7 mAh g-1 at 5 C with 97.8% retention after 450 cycles.
• Exceptional long-term cycling stability was observed, with 3000 cycles at 20 C and 94.1% capacity retention.

Conclusions:

• Amorphous engineering of MOF-aramid fiber interfaces significantly improves Li+ transport and battery performance.
• The study reveals the mechanism of coupled interfaces in enhancing Li+ migration and polyiodide integration.
• This work provides a pathway for designing advanced composite solid electrolytes for high-performance Li-I2 batteries.