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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
Ionic liquid based lithium battery electrolytes: charge carriers and interactions derived by density functional
Knut Angenendt1, Patrik Johansson
1Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
The Journal of Physical Chemistry. B
|May 20, 2011
Summary
Lithium-ion conducting species in ionic liquids (ILs) are often negatively charged triplets. Their properties, tunable via salt and IL selection, significantly impact battery performance. DFT calculations can predict these species and electrolyte behaviors.
Area of Science:
- Electrochemistry
- Materials Science
- Computational Chemistry
Background:
- Solvation of lithium salts in ionic liquids (ILs) forms unique lithium-ion conducting species.
- These species differ significantly from those in traditional non-aqueous electrolytes, often being negatively charged and ionic.
- In IL-based electrolytes, triplet ion aggregates are frequently dominant, influencing conductivity and ion mobility.
Purpose of the Study:
- To investigate the nature of lithium-ion carrying species formed in ionic liquid electrolytes.
- To understand how the charge, stability, and size of these species affect electrochemical properties.
- To explore the potential for tailoring these species for enhanced battery applications.
Main Methods:
- Density Functional Theory (DFT) calculations were employed.
- Combinations of various ionic liquids and lithium salts were computationally modeled.
- Electrolyte properties resulting from these combinations were analyzed.
Main Results:
- DFT calculations successfully predicted the charge-carrying species formed from IL-lithium salt combinations.
- The study identified that triplet ion aggregates are common and significantly impact electrolyte properties.
- The charge, stability, and size of these triplets were shown to influence ion conductivity and lithium-ion delivery.
Conclusions:
- The properties of lithium-ion carrying species in IL electrolytes can be predicted using DFT.
- Anion selection in lithium salts and ILs offers a route to tailor these species.
- This tailored approach holds promise for optimizing lithium-ion battery performance.
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