Nguyen, Dinh Quan Bae, Hyun Woo Jeon, Eun Hee Lee, Je Seung Cheong, Minserk Kim, Honggon Kim, Hoon Sik Lee, Hyunjoo 2024-01-20T23:00:22Z 2024-01-20T23:00:22Z 2021-08-31 2008-08-15 0378-7753 https://pubs.kist.re.kr/handle/201004/133227 A series of imidazolium-based zwitterionic compounds having both a propylsulfonate group a 3-position and an ester group at 1- or 2-position are synthesized and their interactions LiPF6 are investigated. FT-IR study and theoretical calculation using density functional theory show that the interactions of the zwitterionic compound with LiPF6 varies significantly with the location of the ester group on the imidazolium ring. The electrochemical stability of the imidazolium-based zwitterionic compound is significantly improved by introducing an ester group at the C-2 position of the imidazolium ring. Cycle performance tests show that the initial cell capacity remains almost unchanged up to 100 cycles at 1/2 C when 25 wt.% of 2-(acetozymethy)-1-butylimidazolium-3-propylsulfonate is added to the model electrolyte consisting of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethylmethyl carbonate (EMC) (EC/DMC/EMC = 1/1/1 v/v/v), whereas the capacity of the cell containing an unsubstituted or methyl-substituted imidazolium compound at the C-2 position, 1-(acetoxymethyl)imidazolium-3-propylsulfonate or 1-(acetoxymethyl)-2-methylimidazolium-3-propylsulfonate as an additive, starts to decrease rapidly just after a few cycles. (C) 2008 Published by Elsevier B.V. English ELSEVIER SCIENCE BV IONIC LIQUIDS MOLTEN-SALTS APPROXIMATION EXCHANGE MECHANISMS ENERGY CELLS GEL Zwitterionic imidazolium compounds with high cathodic stability as additives for lithium battery electrolytes Article 10.1016/j.jpowsour.2008.04.047 1 JOURNAL OF POWER SOURCES, v.183, no.1, pp.303 - 309 JOURNAL OF POWER SOURCES 183 1 303 309 scie scopus 000259659300040 2-s2.0-46749088597 Chemistry, Physical Electrochemistry Energy & Fuels Materials Science, Multidisciplinary Chemistry Electrochemistry Energy & Fuels Materials Science Article IONIC LIQUIDS MOLTEN-SALTS APPROXIMATION EXCHANGE MECHANISMS ENERGY CELLS GEL ester imidazolium zwitterionic lithium battery ionic liquids cycle performance