5V电解液 计算.pdf

Article pubs.acs.org/JPCB Oxidation Potentials of Functionalized Sulfone Solvents for High- Voltage Li-Ion Batteries: A Computational Study Nan Shao,† Xiao-Guang Sun,† Sheng Dai,†,‡ and De-en Jiang*,† †Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States ‡Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37966, United States ABSTRACT: New electrolytes with large electrochemical windows are needed to meet the challenge for high-voltage Li-ion batteries. Sulfone as an electrolyte solvent boasts of high oxidation potentials. Here we examine the effect of multiple functionalization on sulfone’s oxidation potential. We compute oxidation potentials for a series of sulfone-based molecules functionalized with fluorine, cyano, ester, and carbonate groups by using a quantum chemistry method within a continuum solvation model. We find that multifunctionalization is a key to achieving high oxidation potentials. This can be realized through either a fluorether group on a sulfone molecule or sulfonyl fluoride with a cyano or ester group. 1. INTRODUCTION higher oxidation potential. This simple correlation can be used Li-ion batteries have great potential to revolutionize the as the first guide to search for molecules with large oxidation transportation industry. The energy density of Li-ion batteries potential. One straightforward way to change the HOMO level is proportional to the voltage of the cell, so high voltage leads to