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

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