Phase Diagrams and Conductivity Characterization of Some  PEO  ‐ LiX Electrolytes

Abstract

PEO‐normalLiX false(X=CF3SO3−,ClO4−,and AsF6−false) systems have been characterized by x‐ray diffraction and optical microscopy, and the resulting phase diagrams are taken into account for the interpretation of ac impedance measurements. Eutectic reactions and multiple‐intermediate‐compound formation are characteristic of most systems. Simple phenomenological models do not explain the overall conductivity behavior. The activation energy of ion transport is independent of the anion, and remains mainly constant at 0.7 eV over the concentration range studied for T>60°C . Ion‐pair formation seems to occur at low salt concentration.

PEO nanocomposite polymer electrolyte for solid state symmetric capacitors

“…a pure capacitor is a straight line parallel to the imaginary axis (Z ), whereas in a real case, the observed steep rising response owes to the electrode-electrolyte interface. The conductivity measurement on each composition is shown in figure 8, which is the indicative that the composition (PEO 70 AgI 30 ) 70 (AC) 30 has highest conductivity (σ ∼ 1.926 × 10 −3 S cm −1 ), and this composition is used as an electrode for each symmetric capacitor and referred to as PAC(OCC). …”

“…In the present paper, the ionic conducting solid polymer electrolyte prepared by the addition of inorganic oxide fillers Al 2 O 3 and SiO 2 to the standard SPE (PEO 70 AgI 30 ) system has been reported. The synthesized nanocomposite solid polymer electrolyte has been characterized by several analytical techniques, such as differential scanning calorimetry (DSC) and thermogravimetric (TGA) studies, electrical studies such as conductivity and transport number measurements.…”

“…For the symmetric capacitor, polymer-based electrode having composition (PEO 70 AgI 30 ) 1−x (AC) x (x = 10 ≤ x ≤ 100) was used as electrode. In a separate paper, the best AC concentration and the composition (PEO 70 AgI 30 ) 70 (AC) 30 has been optimized and is found to exhibit the highest ionic conductivity (σ ∼ 1.926 × 10 −3 S cm −1 ) which is referred as optimum conducting composition and denoted as PAC(OCC). Solid state capacitor based on PEO/AgI/activated carbon (PAC) electrodes in NPEs have been characterized using experimental techniques such as AC impedance spectroscopy, Bode plot, cyclic voltammetry, leakage current and discharge profile.…”

Phase Diagrams for the PEO-LiX Electrolyte System.

“…It has been shown that many of these ionically conducting materials are not single phase and phase diagram investigations reveal the presence of ] more than one compound (4,5,6). It has also been shown for the PEOLiBF, system that allotropes exist depending upon the solvent used -(7 .…”

“…Phase diagrams for a number of alkali metal salt-PEO systems have been established (4,5,6,(14)(15)(16)(17) All subsequent handling of the materials was carried out in a <1% RH dry room. All of these lithium salts and tne PEO dissolve fairly easily in acetonitrile and films were cast from this solvent.…”