Lithium LiTFSI

The interfacial properties of gel electrolytes containing ethylene carbonate immobilized in a polyacrylonitrile (PAN) matrix with a lithium (bis)trifluoromethane sulfonimide (LiTFSI) salt have been studied 1139]. SEI stability appeared to be strongly dependent on the LiTFSI concentration. A minimum value of / SE1 of about 1000 Qcm2 was obtained after 200h... 

The lithium transference number calculated for 7/LiTFSI was 0.47 at 30°C, showing that anions were effectively trapped by methoxyboron unit. 

Interestingly, the nonpolyether-type polymer electrolyte 7 showed a relatively high lithium transference number of 0.47 in the presence of LiTFSI. This is possibly due to the absence of strong binding of ether oxygen to the lithium cation. Moreover, anion trapping of the boron atom is not retarded by coordination of oxygen to the... 

Monomer II is also a polymerizable IL composed of quatemized imidazoliimi salt, as shown in Figure 29.1. This monomer is liquid at room temperature and shows a Tg only at —70°C. Its high ionic conductivity of about 10 S cm at room temperature reflects a low Tg. Although the ionic conductivity of this monomer decreased after polymerization as in the case of monomer I, it was considerably improved by the addition of a small amount of LiTFSI. Figure 29.3 shows the effect of LiTFSI concentration on the ionic conductivity and lithium transference number ( Li ) for polymer II. The bulk ionic conductivity of polymer II was 10 S cm at 50°C. When LiTFSI was added to polymer 11, the ionic conductivity increased up to 10 S cm After that, the ionic conductivity of polymer II decreased gradually with the increasing LiTFSI concentration. On the other hand, when the LiTFSI concentration was 100 mol%, the of this system exceeded 0.5. Because of the fixed imidazolium cations on the polymer chain, mobile anion species exist more than cation species in the polymer matrix at this concentration. Since the TFSI anions form the IL domain with the imidazolium cation, the anion can supply a successive ion conduction path for the lithium caiton. Such behavior is not observed in monomeric IL systems, and is understood to be due to the concentrated charge domains created by the polymerization. 

Lithium bis (trifluoromethane sulfonyl)imide (LiTFSI) LiN(S02CF3)2 105-110,113... 

Bernhard R, Latini A, Panero S, Scrosati B, Hassoun J. Poly(ethylenglycol)dimethylether-lithium bis(trifluoromethanesulfonyl)imide, pegSOOdme-litfsi, as high viscosity electrolyte for lithium ion batteries. J Power Sources 2013 226 329-33. 

MD simulations were used to study a number of electrolytes of potential interest to lithium battery applications EC DMC/LiPEg [52], EC/LiTESI [53, 54], DMC/ LiTFSI [55], GBL/LiTFSI [55], and acetonitrile doped with LiPEg, LiC104, L1BF4, LiDFOB, LiTFSI [56-58], oligoethers/Li salts [59-61], acetamide/LiTFSI [62],... 

EC/LiBp4 [63], PC/LiBp4 [63, 64], PC/LiPFs [64], DMC/LiBp4 [63], oligoethers/ PiPFg [65-67], and PC/LiTFSI [54]. Most simulations focused on understanding the lithium cation coordination by solvent molecules and cation-anion aggregation. They provided valuable complementary information to the Raman spectroscopy... 

Borodin, O. Smith, G. D. Geiculescu, O. Creager, S. E. Hallac, B. DesMarteau, D., LB Transport in Lithium Sulfonylimide-01igo(Ethylene Oxide) Ionic Liquids and OUgo(Ethylene Oxide) Doped with Litfsi. J. Phys. Chem. B 2006,110, 24266-24274. 

Lassegues, J. C. Grondin, J. Aupetit, C. Johansson, P., Spectroscopic Identification of the Lithium Ion Transporting Species in Litfsi-Doped Ionic Liqttids. J. Phys. Chem. A 2009,113, 305-314. 

Unlike the tremendous interest in simulating pure RTIL solvents, only a very limited number of MD simulations studies of ILs doped with lithium salts have been reported [pyrn][TFSl] doped with LiTFSI and [pyrisHTFSl] doped with LiTFSI (at 303, 333, 393, and 500 K) [86], [l-ethyl-2,3-dimethyl-imidazolium... 

The mechanism of lithium transport was also studied in [pyri3][TFSI] + 0.25 LiTFSI [86]. The LL cation transport was found to occur primarily by exchanging TFSF anions in the first coordination shell of a LL with a smaller ( 30%) contribution also due to Li" cations diffusing together with their first coordination shell. It is important to note that despite high conductivity of IL-based electrolytes ( 10 S/cm) the hthium contribution to the charge transport remains quite low. 

Borodin O et al (2006) Li Transport in lithium sulfonylunide-oligo(ethylene oxide) ionic liquids and oligo(ethylene oxide) doped with LiTFSI. J Phys Chem B 110 24266... 

Diddens D, Heuer A, Borodin O (2010) Understanding the lithium transport within a Rouse-based model for a PEO/LITFSI polymer electrolyte. Macromolecules 43 2028... 

Lassegues JC, Grondin J, Aupetit C, Johansson P (2009) Spectroscopic identification of the lithium ion transporting species in LiTFSI-doped ionic liquids. J Phys Chem A 113 305... 

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