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The polymer electrolyte films (poly((vinylidene fluoride)- co -hexafluoropropylene)/LiClO 4 @90:10 w/w, PHL10) were prepared by solution-casting technique and the effect of various dosages of electron beam (EB) irradiation on structure, morphology, thermal, dielectric, and conductivity properties at various dosages. The atomic force microscope topography image shows substantial change in surface morphology due to irradiation and the modification of chemical bonds through chain scission process with increased EB dose was confirmed by Fourier transform infrared spectroscopy studies. NMR studies confirm the change in structural properties due to irradiation. The X-ray diffractometer confirms the decreased crystallinity from 50.10 for unirradiated film to 40.96 at 120 kGy doses; hence, increase in amorphousity due to a decrease in melting temperature from 460 to 418 °C leads to the degradation of the polymer, and the differential scanning calorimetry study reveals the decreased crystallinity with increased irradiation dose. The dielectric and modulus parameters are observed to decrease with increasing frequency as well as temperature. The conductivity increases with frequency and EB dose due to the increased segmental motion of charged ions by chain scission/cross-linking process. The high conductivity of 1.81 × 10 –3 S/cm with the corresponding relaxation time of 1.697 × 10 –6 at 120 kGy dose was observed. The conduction mechanism reveals an Ohmic behavior and the I – V plot exhibits a gradual increase in current with applied voltage as well as irradiation dose. The electrochemical performance of the irradiated polymer electrolyte was improved significantly and hence the polymer electrolytes can be used in solid-state batteries and storage applications after altering the properties by the influence of irradiation.

An asymmetric supercapacitor (ASC) was constructed using a polythiophene/aluminium oxide (PTHA) nanocomposite as an anode electrode and charcoal as a cathode electrode. The highest specific capacitance (C sp ) of the PTHA electrode was found to be 554.03 F g À1 at a current density (CD) of 1 A g À1 and that of the charcoal electrode was 374.71 F g À1 at 1.4 A g À1 , measured using a three electrode system. The maximum C sp obtained for the assembled PTHA//charcoal asymmetric supercapacitor (ASC) was 265.14 F g À1 at 2 A g À1 . It also showed a high energy density of 42.0 W h kg À1 at a power density of 735.86 W kg À1 and capacitance retention of 94.61% even after 2000 cycles.Moreover, it is worth mentioning that the asymmetric device was used to illuminate a light emitting diode (LED) for more than 15 minutes. This PTHA//charcoal ASC also possesses stable electrochemical properties in different bending positions and hence finds a promising application in flexible, wearable and portable energy storage electronic devices.