Hosted by the Department of Chemical and Biomolecular Engineering
Attend a seminar with Elizabeth J. Biddinger, PhD of the Department of Chemical Engineering at The City College of New York, CUNY.
Abstract
Ionic liquids have appealing properties as electrolytes due to their wide electrochemical windows, lack of flammability, moderate conductivities, and structure-property tunability. Due to these characteristics, ionic liquids have been considered for electrolytes in lithium metal and lithium ion batteries. Challenges still exist that limit the application of ionic liquids in lithium-based batteries including poor lithium ion transport, lack of stable solid electrolyte interphase (SEI), and high melting points. To address these challenges, co-solvents and additives can be mixed with the ionic liquid to further tune the properties of the electrolyte. We have investigated two families of ionic liquid mixtures as lithium-containing electrolytes: ionic liquid – ester co solvent mixtures, and ionic liquid – glyme mixtures. In both cases, pyrrolidium-based cations and bis(trifluoromethanesulfonyl)imide ([TFSI]-) anions were utilized for the ionic liquids and LiTFSI served as the base case lithium salt. The physical and electrochemical characteristics of the ionic liquid mixtures were evaluated to better understand how key properties and solvating power affect reversible lithium deposition and stripping across a range of temperatures. Through the use of ionic liquid-based mixtures, many of the desirable properties of the ionic liquids can be retained while the undesired properties of the ionic liquids can be mitigated, making for more favorable electrolytes.
Biography
Elizabeth J. Biddinger is an Associate Professor of Chemical Engineering at The City College of New York, the Deputy Director of the Center for Decarbonizing Chemical Manufacturing Using Sustainable Electrification (DC-MUSE) and an associate editor for ACS Sustainable Chemistry & Engineering. Her research interests are in electrochemical reaction engineering for green chemistry and energy. In particular, she is interested in the electrification of chemical processes that transform wastes or renewable resources into valuable materials, chemicals and fuels for decarbonization and sustainability, and in alternative electrolytes for battery safety and performance.