Abstract:

Commercial lithium-ion batteries have excellent performance at room temperature for a few years (3-5). However, the calendar life and thermal stability (> 50^oC) need to be improved for many applications, including electric vehicles. We have conducted a detailed investigation of the effect of thermal stabilizing additives, including dimethyl acetamide, vinylene carbonate, and lithium bis(oxalato) borate, on the reactions of the liquid electrolyte and the electrolyte with the surface of the cathodes and anodes. The surfaces of the electrodes have been characterized with a combination of IR-ATR, XPS, and SEM. The role of the electrolyte additive in solid electrolyte interface (SEI) formation and stability will be discussed.