Reversible Intercalation of Bis(trif luoromethanesulf onyl) imide Anions from an Ionic Liquid Electrolyte into Graphite for High Performance Dual-Ion Cells

摘要

Ionic liquids (ILs) are promising electrolyte candidates for improving the safety of lithium ion cells. The ionic components of the IL, which is added to the lithium salt in organic solvents as electrolyte, act as charge carriers along with Li ion in the electrolyte. The movement of these charge carriers opens up a possibility of storing the charge by intercalating them in the host matrix. Researchers from the University of Munster propose a novel dual-ion cell in which both Li~+ and the anion from the IL are used to store the charge. The study was performed on metallic Li/KS6 graphite and Li4Ti5O_(12) (LTO)/ KS6 cells. The formulation of 1 M LiTFSI (lithium bis(trifluoromethanesulfonyl)imide) with IL N-butyl-N-methylpyrrolidinium TFSI (Pyr_(14)TFSI) (LiTFSI:Pyr_(14)TFSI = 1:3.34) was used as an electrolyte.