Influence of crystallization on dielectric properties of PEO:LiTFSI polymer electrolyte

Conductivity and dielectric properties of polymer electrolytes PEO:LiN(CF3SO2)2 near glass transition

“…In this range we were able to obtain overcooled amorphous samples as well as samples in semicrystalline state. It should be noted, that detailed information on properties of some of specific electrolyte compositions can be found in our previous publications [9,[19][20][21]. Here we present trends which can be considered as general for PEO:LiTFSI system.…”

“…Close coupling between the segmental motions of the chains and the ionic conductivity has been observed for polymer electrolytes based on poly(ethylene oxide) PEO [6]. Our previous investigations of amorphous polymer electrolytes based on PEO confirmed that this coupling is also valid for the systems with a significant amount of salt [7][8][9]. Description of ion motion through the matrix becomes more complex when existence of stoichiometric PEO:salt complexes is taken into account.…”

“…Separation of the two phenomena, was possible by fitting equivalent circuit. The details of fitting and analysis procedure were described previously [9]. The elements used to reproduce the impedance spectra were: resistor (R), capacitor (C) and the Havriliak-Negami function (H) expressed as:…”

The effects of SiO 2 and TiO 2 nanofillers on structural and electrochemical properties of poly(ethylene oxide)–EMIHSO 4 electrolytes

“…Furthermore, a segmental motion arises from the local relaxation of dipoles in the PEO chains under external excitation, such as an electrical field.This will lead to a reorientation of polar segments (C-O bonds) in the polymer backbone. When an ionic conductor is added into PEO, the segmental motion could be coupled with the ionic dipolar relaxation or the motion of the charge carriers [1,2]. Therefore, a low degree of crystallinity that provides more flexibility to the polymer backbone is necessaryto achieve high ionic conductivity.…”

Investigation on ion conduction behaviour in Zn-ferrite based polymer nanocomposite electrolyte

“…This inference is based on the fact that PEO exhibits three types of relaxation [31] namely, α, β and γ relaxations. The α-relaxation is observed near melting point of PEO (T m~3 38 K) and attributed to motion of the chains associated with crystalline phase and segmental motion of host polymer chain [32]. The β-relaxation is usually detected in the temperature 250-350 K and related to local motion of chain segment or side group.…”