Operando Infrared Spectroscopy Study on Electrode-Electrolyte Interface in Lithium Secondary Batteries Using Polyethylene Oxide-Based Electrolyte

摘要

(Electro-)chemical reaction at the electrode-electrolyte interface, including the formation of solid electrolyte interphase (SEI), is a crucial element to improve the performance of lithium secondary batteries. Numerous operando measurements, for instance, XPS, Raman, and infrared spectroscopy (IR) technique have been performed to study the reaction proceeding on the electrode. Operando attenuated total reflection (ATR) infrared spectroscopy technique especially has received much attention due to its high sensitivity to organic molecules, and have successfully revealed the oxidation mechanisms of carbonate solvents on the common electrode (LiNi_xMn_yCo_(1-x-y)O_2). On the contrary, the electrode-electrolyte interface of the polymer electrolytes, which is considered as a next-generation electrolyte owing to its flame retardancy and structural stability, is not well understood.