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Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
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Ionic Conductivity Enhancement of Polymer Electrolytes by Directed Crystallization.
Changhao Liu1, Xiaomin Tang1, Yangyang Wang2
1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States.
ACS Macro Letters
|May 16, 2022
Summary
Hot stretching poly(ethylene oxide) (PEO) solid polymer electrolytes (SPEs) aligns PEO crystalline lamellae. This improves ion conductivity by shortening the ion pathway through the SPE film.
Area of Science:
- Materials Science
- Electrochemistry
- Polymer Science
Background:
- Solid polymer electrolytes (SPEs) are crucial for advanced battery technologies.
- Poly(ethylene oxide) (PEO)-based SPEs offer potential but often suffer from limited ionic conductivity.
- Optimizing ion transport pathways in SPEs is essential for enhancing device performance.
Purpose of the Study:
- To investigate the impact of hot stretching on PEO-based SPEs.
- To understand how crystalline lamellar orientation affects ionic conductivity.
- To enhance the through-plane ionic conductivity of SPE films.
Main Methods:
- Hot stretching of PEO-based SPE films above the melting point under an inert atmosphere.
- Crystallization at room temperature while maintaining strain.
- Analysis using Wide-Angle X-ray Scattering (WAXS) and Small-Angle X-ray Scattering (SAXS).
Main Results:
- Hot stretching induced preferred orientation of PEO crystalline lamellae.
- This orientation reduced ion-conduction pathway tortuosity in the through-plane direction.
- Ionic conductivity was enhanced by 1.4- to 3.5-fold in the through-plane direction.
Conclusions:
- Hot stretching is an effective method to improve ionic conductivity in PEO-based SPEs.
- Aligning crystalline lamellae significantly enhances ion transport.
- This technique offers a pathway to develop high-performance solid-state electrolytes.
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