Fluorinated Electrolytes for 5-V Li-Ion Chemistry: Probing Voltage Stability of Electrolytes with Electrochemical Floating Test

Abstract

© The Author(s) 2015. Published by ECS. A series of electrolyte formulations containing fluorinated cyclic carbonates and fluorinated linear carbonates with LiPF < inf > 6 has been evaluated as electrolyte solvents for high-voltage Li-ion batteries. The anodic stability of the new electrolytes on fully charged spinel LiNi < inf > 0.5 Mn < inf > 1.5 O < inf > 4 (LNMO) cathode was examined by electrochemical floating tests. The effects of fluorine substitution on the cyclic and linear carbonate, ratio of cyclic vs. linear carbonate, and LiPF < inf > 6 concentration on the electrolyte oxidation stability were investigated. Based on this study, the floating test proved to be an effective tool for identification of stable electrolyte materials.