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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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