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Several new sulfonium ionic liquids (ILs) with dicyanamide ([DCA]−) and bis(trifluoromethylsulfonyl)imide ([TFSI]−) counter anions have been synthesized. Their viscosity and ionic conductivity values were determined. The ILs with [DCA]− were previously prepared by the metathesis reaction involving silver dicyanamide (AgDCA). We report here a very convenient and much less expensive method using an ion-exchange resin. The structures of these ILs have been confirmed by 1H-NMR, 13C-NMR, and elemental analysis. Some of these sulfonium ILs displayed low viscosity (< 30 cP) and high ionic conductivity (> 10 mS cm−1). A concluding remark on structure-property relationship has also been drawn involving alicyclic and cyclic sulfonium cations vs. [DCA]− and [TFSI]− anions. [ABSTRACT FROM AUTHOR]

Development of new solvent/additive electrolyte is emerging field of research towards the improvement of ion transport and solid-electrolyte-interface formation in Li-ion battery (LIB). We perform extensive atomistic molecular dynamics simulations with LiPF 6 in ethylene carbonate (EC) in presence of a new class of boron (B) based heterocyclic anion receptor additives; C 2 HBNO(NO 2) 2 , and C 2 HBNS(NO 2) 2 and their trimers B[C 2 HBNO(NO 2) 2 ] 3 , and B[C 2 HBNS(NO 2) 2 ] 3 to investigate the efficacy of this class of additives in regulating the solvation and transport properties of Li+ ions as compared to the reference LiPF 6 /EC solution that contained TPFPB, a commonly used B-based additive. Our designed additives in several aspects show their efficacy. Among all, C 2 HBNS(NO 2) 2 is found to be the most efficient PF 6 - trapper that reduces ion pair formation. It promotes diffusion of Li+ and EC, improves the transference number, and reduces viscosity of solution, as compared to TPFPB. Further, it improves the ionic conductivity and drift velocity under a wide range of temperatures and external electric fields, respectively. Some of the computed properties are in agreement with the available experimental results. Our study would facilitate the design and synthesis of this class of additives to open up new possibilities of accelerating the LIB power sources for portable appliances. [Display omitted] • Condensed phase property of new B-based anion receptors (superhalogen) is explored. • Their presence reduces the self-association of Li+ and formation of Li + PF6- ion pair. • C 2 HBNS(NO 2) 2 is identified as the most efficient compared to commonly used B(C 6 H 5) 3. • Its presence promotes transport property inspite of Li+'s bulky solvation sheath. • It improves conductivity, drift velocity at various temperatures and electric fields. [ABSTRACT FROM AUTHOR]