Inorganic-Organic Hybrid Ionic Liquid Electrolytes for Na Secondary Batteries

摘要

Physical and electrochemical properties of the three inorganic-organic hybrid ionic liquid electrolytes for Na secondary batteries (Na[FSA]-[TMHA][FSA], Na[FSA]-[DBDM][FSA], and Na[FSA]-[[AS[4.5]][FSA], where TMHA~+ trimethylhexylammonium cation, DBDM~+ = dibutyldimethylammonium cation, AS[4.5]~+ = 5-azoniaspiro[4.5]nonane, and FSA~- = bis(fluorosulfonyl)amide anion) have been investigated. In all the three systems, the liquid phase is observed at room temperature in a certain range of Na[FSA] fraction. Ionic conductivity and viscosity of the three systems obey the VTF equations and the highest ionic conductivity is observed for the Na[FSA]-[[AS[4.5]][FSA] in the present series. Their electrochemical windows are ～5 V and Na metal electrodeposition/dissolution are observed around 0 V vs. Na~+/Na.