Magnesium Battery Electrolytes with Improved Oxidative Stability Enabled by Selective Solvation in Fluorinated Solvents
- Nathan T. Hahn*Nathan T. Hahn*Email: [email protected]Joint Center for Energy Storage Research, Lemont, Illinois 60439, United StatesMaterial, Physical and Chemical Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185, United StatesMore by Nathan T. Hahn
- Ethan P. Kamphaus
- Ying Chen
- Vijayakumar Murugesan
- Karl T. Mueller
- Lei Cheng
- , and
- Kevin R. Zavadil
Practical Mg batteries require electrolytes that are stable both toward reduction by Mg metal and oxidation by high voltage cathodes. State-of-the-art Mg electrolytes based on weakly coordinating Mg salts utilize standard ether-type solvents (usually glymes) due to their reductive stability. However, the oxidative stabilities of these solvents are less than ideal, leading to difficulties in realizing the high oxidative stabilities of recently developed salts. On the other hand, alternative solvents with greater oxidative stability are typically unable to support Mg cycling. In this work, we report a selective solvation approach involving the combination of glyme and hydrofluoroether solvents. Selective solvation of Mg2+ by the glyme solvent component increases the oxidative stability of the glyme while maintaining sufficient reductive stability of the non-coordinating hydrofluoroether. We show that this approach enables the design of electrolytes with greater oxidative stability than glyme-only electrolytes while retaining enough reductive stability to cycle Mg metal. We also relate the influence of various coordination interactions among the solvents and anions with Mg2+ to their electrochemical stabilities to better inform the design of future electrolytes.
This article is cited by 1 publications.
- Heonjae Jeong, Dan-Thien Nguyen, Yingjie Yang, D. Bruce Buchholz, Guennadi Evmenenko, Jinghua Guo, Feipeng Yang, Paul C. Redfern, Jian Zhi Hu, Karl T. Mueller, Robert Klie, Vijayakumar Murugesan, Justin Connell, Venkateshkumar Prabhakaran, Lei Cheng. Electrolyte Reactivity on the MgV2O4 Cathode Surface. ACS Applied Materials & Interfaces 2023, 15
, 48072-48084. https://doi.org/10.1021/acsami.3c07875