A Novel Electrolyte Salt Additive for Lithium Ion Batteries with Voltages Greater Than 4.7 V

Abstract

Lithium bis(2-methyl-2-fluoromalonato)borate (LiBMFMB), as an additive in conventional electrolyte for LiNi0.5Mn1.5O4, exhibits improved coulombic efficiencies and cycling stability. Cyclic voltammograms indicate the cells with additive form good SEIs during the first cycle whereas no additive cell needs more cycles to form a functional SEI. XPS reveals LiBMFMB could reduce the decomposition of LiPF6 salt and solvents, resulting in thinner SEI.