| 초록 |
Carbonate-based electrolytes are commonly used as electrolytes in lithium ion batteries (LIBs). Linear carbonates are especially good electrolytes due to their high ionic conductivity. However, their flammable property makes LIBs thermally unstable, which may cause ignition and explosion of LIBs. Due to the unique electrochemical and thermal properties, ionic liquids (ILs) are promising electrolytes for LIBs. The ILs synthesized in this research consist of pyrrolinium-based cations with various alkyl substituents on the nitrogen and FSI- or TFSI- as an anion. The characteristics of the synthesized ILs were analyzed by NMR, impedance spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimeter (DSC). 1-Ethyl-2-methoxypyrrolinium-FSI (E(OMe)pyrl-FSI) showed the highest ionic conductivity (11.84 mS/cm), which is higher than that of carbonate electrolyte, and had high decomposition temperature (Td, 196.9 ℃), guaranteeing its thermal stability. |
