| 초록 |
Lithium ion batteries (LIBs) have some advantages such as a high energy density, negligible memory effect and a less self-discharge. However, LIBs with carbonate electrolytes are flammable owing to the relatively low thermal stability of the carbonate solvent. Under this circumstance, ionic liquids come into highlight for their thermal stability such as nonvolatile and nonflammable. ILs are salts that exist as liquid state at room temperature although they are composed of ionic species, cations and anions. For this composition of ionic species, ILs show the unique properties such as high ionic conductivity, non-volatility, and non-flammability as well as a wide liquid range and wide electrochemical stability window. In this work, novel acyclic ammonium-based ionic liquids with or without an N,O-acetal substituent were synthesized and their physicochemical and electrochemical properties were characterized. Among these acyclic ammonium based ionic liquids, less bulky ammonium cations(N112,1O1-TFSI) having a methoxymethyl group showed better cycle performance at various C-rates. |
