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The ionic conductivity of lithium based solid polymer films prepared from poly (ethylene oxide) (PEO) and lithium hexafluoarsenate (LiAsF 6 ) with varying compositions of plasticizers like dibutyl sebacate (DBS) and ethylene carbonate (EC) was measured by AC impedance method. Polymer film composition viz. (PEO) 8 -LiAsF 6 -(DBS) 0.4 -(EC) 0.1 has been evaluated as an optimum composition as evidenced from its high conductivity and freestanding ability. The high conductivity observed for the polymer electrolyte with this composition has been attributed to an enhanced amorphous character and a reduced energy barrier to the segmental motion of lithium ions in the matrix. The temperature dependence of conductivity on the polymer films, with and without plasticizers, appears to obey the Arrhenius law. However, the activation energy of the plasticized polymer film is 0.81 KJ/mol, a value considerably lower than 10 KJ/mol obtained for the unplasticized electrolyte, making the polymer to be a prospective candidate as lithium-ion conducting electrolyte for rechargeable lithium batteries.

Petroleum based mineral oils are mostly used for power apparatus insulation applications. They are not biodegradable and difficult to decompose the result of which has led to the development of vegetable based oils. Analysis of partial discharge characteristics of vegetable oil is very important, before suggesting it as an alternate to mineral oil for liquid insulation in high voltage apparatus. This paper deals with the analysis of partial discharge characteristics of extra virgin olive oil, castor oil and mineral oil. Partial discharge signals were measured with the help of an innovative PD detection system PDBASEII. The PRPD pattern, time domain and frequency domain characteristics of PD pulses of vegetable oils were measured and they were compared with the mineral oil. Preliminary results show that vegetable oils could be used as an alternate for mineral oils for high voltage insulation applications.

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In this study, the electrical properties of banana leaf fibre-reinforced epoxy resin composites such as dielectric properties, dielectric constant, dissipation factor, and loss factor are tested at various frequencies and temperatures. At frequencies ranging from 1 to 10 kHz and temperatures ranging from 30 to 150o C, the dielectric properties of several composites containing banana leaf fibre are studied. The composite dielectric properties is gradually increased with temperature and decreased with frequency. Correspondingly, the mechanical tests involving a banana leaf fibre epoxy composite are conducted for tensile, bending, impact, and water absorption. The banana leaf fibre has been treated with a 5% sodium hydroxide (NaOH) solution to increase its dielectric and mechanical strength. According to this study, the mechanical strength of bio composites containing up to 60% TBLFE is greater than that of pure epoxy. A thermo gravimetric investigation of composites reinforced with banana fibres has revealed remarkable thermal stability up to 220o C. In a composite made from chemically treated banana fibre pressboard, there is a good bond between the fibres and the matrix. The FESEM surface analysis shows that treated banana leaf fibril insulation boards have a better texture than composites that have not been treated.

Adherent and uniform films of ZnS and ZnS:Ni were deposited reproducibly by Dip coating method onto a glass substrate, under acidic conditions from solutions containing Zinc Nitrate, Nickel Nitrate, Ammonium Nitrate, Sodium citrate, thiourea and distilled water. The growth of ZnS thin films on glass substrates have been thoroughly investigated by SEM, EDAX and X- ray diffraction techniques. The grain sizes (D) of crystallites were estimated using the Scherrer’s formula. Depending on selection of precursors and presence of dopant, ZnS and ZnS films can be of Sphalenite or wurtzite structure. The effect of the dopant on the crystallinity and surface morphology of ZnS thin films have been studied. The surface morphology, which has been evaluated by scanning electron microscope (SEM), shows a relatively flat and uniform surface.