الفهرس 
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Abstract
In the present study Poly vinyl alcohol (PVA) polymer has been used as a base for preparing solid electrolyte. PVA is blended with different concentration of poly(3,4 ethylenedioxythiophene:poly(styrenesulfonate (PEDOT:PSS) to improve conductivity and then the blend was used with MgBr2 and plasticized with succinonitrile (SN) as a base for battery fabrication. The study is divided into four sections and can be summarized as follows: Section (1): Polymer blends of PVA and PEDOT:PSS, were prepared by casting from the aqueous solution. They were characterized using Xray diffraction, SEM, DSC, TGA, FT-IR, ac spectroscopy and optical UV – visible absorption techniques. The thermal analysis doesn’t illustrate significant variations of PVA as blended with different concentrations of PEDOT:PSS. The bulk conductivity of PVA/PEDOT:PSS blend illustrated two orders increase from 1.410-9 S/cm to 3.31×10-7 S/cm while the activation energy reduced from 0.52 to 0.16 eV with increasing PEDOT:PSS concentration up to 4 wt. %. In addition the frequency dependence of conductivity obeys power relation s, 0.3 < s < 0.45 which predicts ionic diffusion. The dielectric constant έ and dielectric loss ” obey Debye dispersion relations in wide range of frequencies and temperatures. A new significant optical broad absorption peak appeared in the visible range around 926 nm. Its height influenced by PEDOT:PSS concentration which suggested direct energy band gap transition (1.05 – 1.2 eV). Section (2): In this section an optimized blend of (PVA/PEDOT:PSS) was loaded with MgBr2 ionic salt to prepare solid electrolyte. Thermo gravimetric analysis (TGA) studied for the different concentration of MgBr2 which showed the activation energy values lie in the range (132 189 kJ/mole). The study of complex impedance in wide range of frequency and temperature was studied for different concentration of MgBr2. The extracted bulk conductivity illustrated an increase of conductivity to approach 9.8 ×10-6 S/cm. In addition the frequency dependence of conductivity suggested ionic conduction which was thermally activated with activation energy in the range 1.10 to 0.18 eV. The study of dielectric constant έ and dielectric loss ” obey in general obeys Debye dispersion relations which suggest ionic besides the interfacial polarization. The study of optical absorption showed an absorption peak in the visible range, which suggested direct band gap transition with Eg in the range 1.15 to 2.35 eV. Section (3): The optimized (PVA/PEDOT:PSS)1-x’(MgBr2)x’ polymer composite was plasticized with SN to prepare an efficient solid electrolyte for battery cell fabrication. The obtained solid electrolytes were subjected structure investigation using; XRD, SEM, FT-IR showed a decrease in the degree of crystalinity with increasing SN concentration which confirms the matrix improvements with the addition of SN. The study of thermo gravimetric analysis illustrated decrease of activation energy from 233 to 105.3 kJ/mole, which suggested the enhancement of compound water release. The study of conductivity showed two orders increase from 9.8×10-6 to 2.83×10-4 S/cm with increasing SN plasiticizer. In addition, the frequency dependence of conductivity predicts ionic diffusion rather than electronic hopping. The dielectric constant έ and dielectric loss ” obey in general Debye dispersion relations in wide range of temperature and frequency. The ionic transference number of mobile ions has been estimated by a dc polarization method and the results reveal that the conducting species are predominately ions. Section (4): Finally magnesium battery with configuration Mg/PE/V2O5 cell has been successfully fabricated and subjected to charge and discharge processes, which illustrated efficient cell with capacity of 4.36 mAh and an internal resistance ≈531.2 Ω. The V2O5 electrode was characterized by XRD, SEM and EDS analysis to determine the chemical reaction in the electrodes which illustrated that the magnesium content of the cathode increased from 0.96% to 2.55% after discharge.