Relationship between Ionic Interaction and NMR Relaxation Behavior in LiClO₄-PC Solution Coexisting with Fumed Metal Oxide

Abstract

Dynamic properties related to 1 H NMR relaxation in SiO2 fine powder/non-aqueous LiClO4 solution was measured for using propylene carbonate (PC) and PC-1,2-dimethoxyethane (DME). The influence of solid phase and variation of effect of DME on ionic mobility is also discussed. For 1 H NMR spectra of PC-DME binary solution, adding of SiO2 powder caused the broadening of NMR signal of 1 H in PC and DME molecules. In pure PC-DME system, since DME is preferentially affected by solids rather than PC, as the ratio of DME increased, values of solvent molecules detected by NMR decreased. In 1 mol/L LiClO4/PC-DME system, as the ratio of DME in solution was higher, The interaction between the PC and the Li + ion is weakened by the decrease of the dissociation degree, and the mobility of the PC was restored.

Anion Donicity of Liquid Electrolytes for Lithium Carbon Fluoride Batteries

“…Figure 6a shows the C 1s and F 1s spectra of the fresh CF x cathode powders. As seen in Figure 6a, the C 1s spectrum shows the characteristic peak (i.e., 284.5 eV) assigned to the C=C bond with sp 2 hybridization, originating from non‐fluorinated carbon [13e, 14, 24, 45] . In addition, typical peaks related to fluorinated carbon species are observed, including semi‐ionic C−F bond, (i.e., ca.…”

Conductivity of LiClO₄/PC-DME Solution Impregnated in LiCoO₂ Powder

“…For the resemble case of the measurement of 1 H NMR for SiO 2 /LiClO 4 -PC 1¹x DME x coexistent system, local viscosity of DME is more susceptible to solid than PC. 10 Variation of ¦E a with the liquid fraction for LiCoO 2 /1 mol L ¹1 LiClO 4 -PC 1¹x DME x solution coexisting systems were shown Fig. S2.…”

Anion Donicity of Liquid Electrolytes for Lithium Carbon Fluoride Batteries

“…For Li j j CF x batteries, the mixture of PC and DME has been widely employed to formulate Li + -ion conductive electrolytes, [9a, 13c,d, 22] due to the fact that PC has inherently a high dielectric constant (ɛ = 65.0 (PC) vs. 7.2 (DME)), [17,23] and DME owns lower viscosity (η = 2.5 (PC) vs. 0.4 cP (DME)). [17,23,24] The binary mixture regulates the dielectric constant and viscosity of the electrolytes, thus balancing the dissociation and transportation of salt in the solvent. [11a, 16h, 25] Effectively, for the equal-weight mixture of PC/DME under study, it shows a relatively high dielectric constant of 31.6 (25 °C) and low viscosity of 0.99 cP (25 °C) (Table S1), which are very close to that of the commonly used solvent mixture of EC/EMC (33.6; 1 : 1, by wt; 25 °C [27] ) for LIBs.…”

“…For Li||CF x batteries, the mixture of PC and DME has been widely employed to formulate Li + ‐ion conductive electrolytes, [9a, 13c,d, 22] due to the fact that PC has inherently a high dielectric constant ( ϵ =65.0 (PC) vs. 7.2 (DME)), [17, 23] and DME owns lower viscosity ( η =2.5 (PC) vs. 0.4 cP (DME)) [17, 23, 24] . The binary mixture regulates the dielectric constant and viscosity of the electrolytes, thus balancing the dissociation and transportation of salt in the solvent [11a, 16h, 25] .…”