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Updated: Aug 14, 2026
11:04
Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
Stable Li Plating/Stripping in LiPF6-Cyclic Ether-Based Electrolytes
Peter-Paul R M L Harks1, Seongjae Ko1, Wenxuan Zhao1
1Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo113-8656, Japan.
Journal of the American Chemical Society
|August 12, 2026
Summary
Researchers developed new lithium-ion battery electrolytes using lithium hexafluorophosphate (LiPF6) and ether solvents. This breakthrough enables stable, high-performance lithium metal batteries without problematic additives, enhancing safety and efficiency.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Lithium metal anodes offer high theoretical capacity but face challenges with electrolyte stability and safety.
- Current electrolytes often use imide salts and ethers, which have stability issues and can corrode battery components.
- Utilizing the common LiPF6 salt is desirable but hindered by its instability and tendency to polymerize ether solvents.
Purpose of the Study:
- To develop LiPF6/ether-based electrolytes that overcome the limitations of current systems.
- To suppress ether polymerization and form protective films on lithium metal anodes.
- To achieve high Coulombic efficiency comparable to state-of-the-art systems without hazardous additives.
Main Methods:
- Formulation of novel LiPF6/ether-based electrolytes.
- Investigation of electrolyte stability and film formation on Li metal.
- Electrochemical performance testing, including Coulombic efficiency measurements.
Main Results:
- Successfully suppressed ether polymerization in LiPF6/ether electrolytes.
- Formed highly functional inorganic-organic bilayer films on Li metal anodes.
- Achieved a high Coulombic efficiency of 99.5% without fluorinated solvents or additives.
Conclusions:
- LiPF6/ether-based electrolytes can be effectively utilized for stable and high-performance lithium metal batteries.
- The developed electrolytes offer a promising alternative to imide-based systems, enhancing safety and potentially reducing costs.
- This work represents a significant advancement for LiPF6-based electrolytes in rechargeable battery technology.
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