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Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
Structure-properties relationships of lithium electrolytes based on ionic liquid.
My Loan Phung Le1, Fannie Alloin, Pierre Strobel
1LEPMI-Grenoble-INP/UJF/CNRS, BP75, 38402 Saint Martin d'Hères, France.
The Journal of Physical Chemistry. B
|December 31, 2009
Summary
New low-melting ionic liquids (ILs) with quaternary ammonium cations and imide anions were synthesized and characterized. These novel ILs demonstrate high electrochemical stability, especially those with short alkyl chains or fluorinated ammonium groups.
Area of Science:
- Materials Science
- Electrochemistry
- Physical Chemistry
Background:
- Ionic liquids (ILs) are versatile materials with tunable properties.
- Quaternary ammonium cations and imide anions are common components in IL synthesis.
- Understanding the structure-property relationships of ILs is crucial for their application.
Purpose of the Study:
- To synthesize and characterize novel low-melting ionic liquids based on aliphatic quaternary ammonium cations and imide anions.
- To investigate the impact of cation structure (alkyl chain length, fluorination) and LiTFSI addition on IL properties.
- To explore the nanoscale organization and electrochemical behavior of these ILs.
Main Methods:
- Synthesis and characterization of ionic liquids.
- Determination of physicochemical properties (melting point, viscosity, density, etc.).
- Electrochemical stability testing and Heteronuclear Overhauser NMR spectroscopy.
Main Results:
- Ionic liquids with small alkyl chain lengths or fluorinated ammonium cations exhibited high electrochemical stability.
- Nanoscale organization with segregation of polar and apolar domains was observed.
- LiTFSI addition influenced the overall properties of the ionic liquids.
Conclusions:
- The synthesized ionic liquids offer promising electrochemical stability for various applications.
- Cation structure significantly impacts the properties and stability of ILs.
- The observed nanoscale organization contributes to the unique characteristics of these ILs.
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