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Glasses for the system x(LiI): {(100-x)[60 Li2O:40(20B2O3:80P2O5)]}have been prepared for different concentration of LiI ranging from 0 to 25 wt.% using the melt quench route. The effect of LiI salt on conductivity (σdc) and dielectric properties such as dielectric constant (ε′), dielectric loss (ε″) of the system is thoroughly using impedance spectroscopic investigation in the frequency range 1Hz - 32 MHz and from room temperature to 403 K. Dielectric properties such as dielectric constant (ε′), dielectric loss (ε″) and the change in dielectric permittivity (Δε) found to increase with increase in LiI concentration. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride-hexafluropropylene) (PVdF-HFP) and poly(methyl methacrylate) (PMMA) gel polymer blend electrolyte system complexed with LiClO4 having different concentrations of propylene carbonate (PC) and diethyl carbonate (DEC) (1:1) plasticizers have been prepared using solution cast technique. Structural and surface morphology have been studied by X-ray diffraction and scanning electron microscopy analysis. Electrical conductivity has been carried out by electrochemical impedance spectroscopy in the temperature range 303 K to 343 K. A maximum electrical conductivity of 1.03 X 10-3 S cm-1 at 303 K has been achieved for the polymer blend gel electrolyte containing 60 wt% of PC:DEC plasticizers. Frequency dependent conductivity follows the Jonscher's power law. The dielectric behavior has been analyzed using dielectric permittivity (ε*), tangent loss (tanδ) and electric modulus (M*) of the samples. Dielectric constant has been found to increase with addition of PC:DEC plasticizers. [ABSTRACT FROM AUTHOR]

Lithium ion conducting NASICON material of the form Li1.3Al0.3-xYxTi1.7(PO4)3 (where x = 0, 0.01 and 0.07) considered as promising electrolyte materials for solid state lithium ion batteries [1, 2] were synthesized via solid state reaction method. The compound was found to have a rhombohedral symmetry with space group R-3c from the x-ray diffraction studies. Further, a partial replacement of Y3+ in the lattice increased the lattice parameters. The room temperature Li+ ion conductivity of the yttrium doped samples deduced from the impedance spectroscopy, in the frequency range 20 MHz to 1 Hz is found to be ~ 10-5 S/cm. The mode of ionic relaxation in grain boundary region was found to be different in yttrium doped samples compared to nominal composition. Core level x-ray photoelectron spectroscopy (XPS) was performed for Al and P. While Al was found to be in single coordination state, P was found to possess two coordination environment - both of which were in tetrahedral configuration. 27Al MAS NMR studies suggested distortion at tetrahedral and octahedral sites due to partial replacement of Al3+ and Ti4+ cations by Y3+. It was found that yttrium enhanced the overall density of the ceramic material - which however did not help increase the bulk Li+ ion conductivity due to blocking effect by aluminum and yttrium phases at grain boundary. [ABSTRACT FROM AUTHOR]

Electrical properties of Lithium based Li1.3Al0.3-xYxTi1.7(PO4)3 (LAYTP) system was prepared using solid state reaction route. The samples were subjected to differing duration of sintering. X-ray diffraction was used to investigate the microstructure while density measurement was performed to determine the effect of sintering on the density of the prepared samples. Electrical properties of the material were studied using impedance spectroscopy, in frequency range 20 MHz to 1 Hz and in temperature range 303 K to 423 K. It was found that sample with least amount of yttrium and which was sintered for least duration had superior conductivity over other samples. It was also found that grain boundary conductivity improved marginally for sample with higher proportion of yttrium heat treated for longer duration. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride-hexafluropropylene)(PVdF-HFP) and Polymethylmethacrylate(PMMA) based gel polymer electrolytes comprising Propylene Carbonate and Diethyl Carbonate mixed plasticizers and different concentrations of Lithium Perchlorate (LiClO4) salt have been prepared using a solvent casting technique. Electrical conductivity and transference number measurements have been carried out by Electrochemical Impedance Spectroscopy in the temperature range 303 K to 363 K and Wagner's Polarization method respectively. The maximum room temperature conductivity of 2.83 ×10-4 S cm-1 has been observed for the gel polymer electrolytes at 7.5 wt% LiClO4. The variation of ac conductivity with frequency has been discussed. [ABSTRACT FROM AUTHOR]

System-1: PVA-PEO-PEG-AgNO3 and System-2: PVA-PEO-EC-LiCF3SO3, are two blend systems prepared for different concentrations of Al2O3 nano-filler ranging from 2 to 10 wt%. The effect of Al2O3 nano filler on the conductivity (σdc) and dielectric properties such as dielectric constant (έ) and dielectric loss (s") of the systems is thoroughly investigated using impedance spectroscopic analysis technique. [ABSTRACT FROM AUTHOR]

In the present study, the PVA-PEO-EC-LiCF3SO3 blend system was prepared using solution cast technique. The system was prepared by taking 5 different concentrations LiCF3SO3 in the range of 3wt% to 11 wt%, at a fixed proportion of the rest of the constituents. These blend films had been exposed to O7+ radiations of 80 MeV at a current of 1pnA at a fluence of 1×1012 ions/cm². The conductivity variation of the specimens is investigated using impedance spectroscopy wherein; the conductivity enhances drastically upon irradiation at all the concentrations of salt. The thermal characteristics of the blend films are being studied using Differential Scanning Calorimetry. [ABSTRACT FROM AUTHOR]

Thin solid polymer electrolytes based on poly-ethylene oxide (PEO) and silver triflate (AgCF3SO3) dispersed with nanoparticles (SiO2) have been prepared by solution casting technique. Electrical properties of PEO-AgCF3SO3-SiO2 system were investigated by impedance spectroscopy. Further from impedance spectroscopy quantity such as complex dielectric constant and loss tangent were computed. Conductivity was studied for prepared films and the results are discussed. [ABSTRACT FROM AUTHOR]

A new ion conducting nano composite polymer electrolytes (NCPEs) thin film based Poly (ethylene Oxide) PEO with AgCF3SO3 salt and SiO2 as nano filler has been prepared by solution- casting method. The salvation of porous filler with PEO has been confirmed by IR spectral studies. AC conductivity in the temperature range (303-328 K) is measured to evaluate the conductivity of the polymer electrolytes. The effect of the addition of nano porous fillers on the ionic conductivity in the polymer electrolyte has been studied. [ABSTRACT FROM AUTHOR]

AC Conductivity measurements have been used to study the transport properties of PbI2 doped silver boro-vanadate glasses prepared by melt quenching technique. The samples are characterized by XRD and DSC measurements. A correlation between Rτ, the decoupling index and σdc has been observed. The observed conductivity values suggest enhancement in conductivity by the introduction of PbI2 salt in the host glass matrix. [ABSTRACT FROM AUTHOR]

Effect of swift heavy ion irradiation on conductivity of blend electrolyte system [(PEO50:PAM50)+x%(NaCF3SO3), x=5, 7.5, 10, 12.5, 15, 17.5] with O6+ ion at four different fluences is investigated. The samples are prepared using solution cast technique and films are subjected to irradiation at room temperature. Conductivity is measured for pristine and irradiated sample as a function of frequency in the range 2 Hz – 2MHz from ambient temperature up to 338 K. It is observed that conductivity increases with fluence. Highest conductivity value is found to be 3.2375×10−4 S/cm at 338 K for fluence of 1×1012 ions/cm2 for sample containing 17.5 wt% NaCF3SO3. SEM and X-ray diffraction techniques have been conducted for the blend electrolytes before and after irradiation to completely understand the changes in the surface morphology. [ABSTRACT FROM AUTHOR]

In the present paper, AC impedance studies have been measured to evaluate ion conduction behavior of (PVdF-HFP – PMMA) + (PC-DEC) + LiClO4 gel polymer electrolyte system prepared by solution casting method. Structural characterization and morphology has been carried out using XRD and SEM respectively. The AC conductivity and dielectric permittivity, electric modulus and relaxation mechanism have been studied. The variation of ac conductivity with frequency obeys Jonscher power law. Maximum value of dielectric constant ε’ in the lower frequency region has been observed for the gel polymer electrolyte containing 7.5 wt% LiClO4. The highest conducting sample shows the shortest relaxation time. [ABSTRACT FROM AUTHOR]

In the present study, the PVA-PEO-EC-LiCF3SO3 polymer electrolytes are prepared using solution cast technique for different concentrations of Al2O3 ranging from 2 to 10 wt%. The study deals with the investigation of the influence of Al2O3 concentration on the electrical properties and crystallinity of the polymer electrolytes. The conductivity studies are carried out using impedance spectroscopic analysis and the variation in crystallinity is investigated using XRD technique. [ABSTRACT FROM AUTHOR]

PVA-PEO-EC-LiCF3SO3 blend system has been prepared using solution cast technique wherein, plasticizer (Ethylene Carbonate (EC)) and salt (Lithium Trifluoromethanesulfonate (LiCF3SO3)) concentrations are varied. The conductivity studies are carried out using impedance spectroscopic analysis. The relaxation time is obtained using frequency dependent (Z'/Z'max) plot. A comparative study between conductivity (σ) and conductivity relaxation time (τ) has been carried out. [ABSTRACT FROM AUTHOR]

In the present work, the PVA-PEO-EC-LiCF3SO3 blend specimens complexed with 3 wt% LiCF3SO3 salt have been irradiated, using swift heavy O7+ ion irradiation of 80MeV. These blend films have been irradiated with four different fluences ranging from 1×1011 to 3×1012 ions/cm2. Effect of radiations on conductivity, power law exponent and relaxation time of the films has been investigated in the present study. Conductivity is observed to enhance on increasing the fluence upto 3×1011 ions/cm2 and drops with further increment of fluence. However, all the irradiated blend specimens show higher conductivity as compared to pristine blend specimen. [ABSTRACT FROM AUTHOR]

Present study reports the characterization studies on silver based PEO-PMMA-PEG nano composite polymer electrolyte system, prepared by solution cast technique. The complexation among various constituents of polymer samples was carried by XRD and FTIR analysis. Thermal analysis of the samples was carried out by DSC study. [ABSTRACT FROM AUTHOR]

PEO-LiCF3SO3-Al2O3-PEG systems; one with varying amount of plasticizer and other with different amount of filler concentration were prepared using solution cast technique. The relaxation times derived from electrical modulus and ionic conductivity were compared in both the systems. Impedance spectroscopy has been used to study the effect of filler and plasticizer on conduction process at different temperatures from 303 to 323K and in the frequency range of 3.2MHz to 10Hz. [ABSTRACT FROM AUTHOR]

The PVA-PEO blended polymer films complexed with silver nitrate salt and PEG plasticizer were prepared by solution cast technique. The prepared polymer films are characterized by XRD, DSC and impedance spectroscopy. The electrical properties of the blended plasticized polymer films have been discussed. [ABSTRACT FROM AUTHOR]

Electrical conductivity and impedance measurements were carried out for a new mixed metal iodide salt doped silver vanado-borate i.e., [(PbI2-CuI)-Ag2O-V2O5-B2O3] super-ionic glass system. The impedance plots (Z″ vs. Z′) for all the prepared glass samples were recorded and found to exhibit depressed semi circles over the studied temperature range. Frequency dependence of the imaginary part of impedance Z″ and the imaginary part of modulus M″ at different temperatures were also investigated. Also, relaxation dynamics in framework of modulus formalism has been discussed. [ABSTRACT FROM AUTHOR]

Silver ion conducting polymer electrolyte films based on Poly acrylamide (PAAM) with EC (Ethylene Carbonate) as plasticizer have been prepared by the novel hot press technique. The complexation of polymer with AgNO3 salt has been confirmed by X-ray diffraction and infrared studies. The electrical conductivity estimated using impedance spectroscopy is observed to be dependent on plasticizer (EC) concentration. The ac conductivity obeys the universal power law and as the temperature increases, the feature of σ(ω) α ωn is more predominant. The ionic conductivity as a function of temperature has been discussed. [ABSTRACT FROM AUTHOR]