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Updated: Mar 10, 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
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Improving Ionic Conductivity and Lithium-Ion Transference Number in Lithium-Ion Battery Separators
Raphael Zahn1, Marie Francine Lagadec1, Michael Hess1
1Laboratory for Nanoelectronics, Department of Information Technology and Electrical Engineering, Eidgenoessische Technische Hochschule Zurich , 8092 Zurich, Switzerland.
ACS Applied Materials & Interfaces
|December 10, 2016
Summary
Separator microstructure geometry is insufficient for predicting lithium-ion transport. Modifying separator surface chemistry significantly impacts ionic conductivity and performance, enhancing battery C-rate capability.
Area of Science:
- Materials Science
- Electrochemistry
- Chemical Engineering
Background:
- Lithium-ion battery separator microstructure is crucial for performance.
- Geometrical analysis alone cannot fully predict ion transport through separator pores.
Purpose of the Study:
- To investigate the impact of separator surface chemistry on lithium-ion transport.
- To demonstrate how surface chemistry influences ionic conductivity and transference numbers.
- To correlate surface chemistry modifications with improved battery performance.
Main Methods:
- Systematic modification of commercial polyethylene separator surface chemistry.
- Maintaining a constant separator microstructure throughout experiments.
- Analysis of separator-electrolyte interactions and their effect on ionic conductivity and lithium-ion transference.
Main Results:
- Separator surface chemistry significantly influences ionic conductivity and lithium-ion transference number.
- Altering surface chemistry, not microstructure, impacts ion transport.
- Increased lithium-ion transference numbers correlate with reduced voltage drops and improved C-rate capability.
Conclusions:
- Separator surface chemistry is a critical factor, beyond microstructure, for optimizing lithium-ion battery performance.
- Tailoring surface chemistry offers a viable strategy to enhance ionic conductivity and battery rate capability.
- Future battery designs should consider surface chemistry for improved efficiency and performance.
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