Performance Improvement of Lithium Metal Batteries Enabled By LiBF3CN as a New Electrolyte Additive

Authors

Oh B. Chae, University of Rhode Island
Venkata A. K. Adiraju, University of Rhode Island
Brett L. Lucht, University of Rhode IslandFollow

Document Type

Article

Date of Original Version

2022

Department

Chemistry

Abstract

A newly synthesized electrolyte additive, lithium trifluoro(cyano) borate (LiBF₃CN), has been investigated for electrochemical performance improvement of lithium metal batteries. The LiBF₃CN has a structure where one fluorine atom of BF₄⁻ is substituted with a cyano group (−CN) prepared by the reaction of boron trifluoride etherate with lithium cyanide. The electrochemical performance in symmetric Li/Li cells and NCM523/Li cells is significantly improved upon the incorporation of LiBF₃CN as an electrolyte additive into a carbonate-based electrolyte. Extensive characterization of the deposited lithium metal reveals that a thin (≈20 nm) and robust SEI composed of LiN_xO_y, Li₃N and Li₂O is formed by the reductive decomposition of the LiBF₃CN additive, which plays an important role in decreasing the resistance and stabilizing lithium deposition/stripping. The insight into the substitution effect of a functional group obtained from this work provides guidance for the design of new electrolyte additives.

Publication Title, e.g., Journal

Journal of The Electrochemical Society

Volume

169

Issue

11

Citation/Publisher Attribution

Chae, O. B., Adiraju, V. A.K., & Lucht, B. L. (2022). Performance Improvement of Lithium Metal Batteries Enabled By LiBF3CN as a New Electrolyte Additive. Journal of The Electrochemical Society, 169(11), 110506. https://doi.org/10.1149/1945-7111/ac9d67

Available at: https://doi.org/10.1149/1945-7111/ac9d67

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.