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Nanoparticle oxide fillers such as SiO2 have been previously shown to affect the properties of polymer electrolytes, especially those based on polyether-lithium salt systems. In this work nanocomposite solid polymer electrolyte films composed of polyethyleneoxide (PEO), lithium triflate (LiCF3SO3) and SiO2 nanofiller (15 nm in size) have been prepared by using solution cast method. At room temperature, the sample 80PEO-20LiCF3SO3 (wt-%) was found to have the highest conductivity of about 2·04 × 10-7 S cm-1. The 88PEO-LiCF3SO3-12SiO2 (wt-%) has high ionic conductivity of about 1·28 × 10-3 S cm-1 at room temperature. The effects of concentration of filler on the dielectric properties of the electrolytes were also studied. Temperature effects on the dielectric properties revealed that the electrolytes to be of the non-Debye type. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) was used as a host polymer with ammonium tetrafluoroborate (NH4BF4) as a doping salt, dimethylformamide (DMF) and a mixture of DMF/polyethylene carbonate (PC) (1 : 1) as solvents cum plasticisers. The CA-DMF/PC-NH4BF4 gel polymer electrolyte system exhibited the highest room temperature ionic conductivity of 4·90 × 10-4 S cm-1. The conductivity-temperature dependent was carried out in the temperature range between 298 and 373 K and the plot of logσ versus 1000/T seen to obey the Arrhenius behaviour. Fourier transform infrared method was used to confirm the polymer-salt complexation. The C=O vibration which can be observed at 1746 cm-1 shifted to lower wavenumbers when the complexes were formed. [ABSTRACT FROM AUTHOR]

Biomaterial-based cellulose is biodegradable, biocompatible and possesses good mechanical properties. Previous studies have proven that it can be used as the separator for various kinds of batteries, such as lead-acid batteries, silver-zinc rechargeable batteries, as an additive for preparation of pasted zinc electrodes for zinc-air batteries and as binders/surface modifiers for graphite anodes for lithium batteries. However, it never intensively been used as a polymer electrolyte in advanced batteries. Substantial progress has been made in the development of proton conductors with high ionic conductivity. Hence, proton batteries can be considered as cost effective alternatives for battery applications. The present study involves the fabrication and characterisation of gelled cellulose polymer proton battery with the configuration Zn/composite cellulose electrolytes/MnO2. The open circuit voltage (OCV) of the cell is ∼1·6 V. The constancy of OCV was tested for over 24 h. The discharge capacity was 24·65 mA h for 0·5 mA and 22·41 mA h for 1 mA. [ABSTRACT FROM AUTHOR]

The insolubility of chitosan in a wide range of organic solvents has limited the application of chitosan especially in electrochemical systems. In order to improve its solubility, acyl modification of chitosan was carried out in the present study. Films of hexanoyl chitosan-based polymer electrolyte were prepared by solution casting technique. The effect of filler on the transport properties of hexanoyl chitosan-LiCF3SO3-ethylene carbonate electrolytes has been investigated. The conductivity for fillerfree polymer electrolyte is 2·75 × 10-5 S cm-1. The addition of 6 wt-%Al2O3 increased the conductivity by one order of magnitude to 1·01 × 10-4 S cm-1. Within the temperature range investigated, the conductivity of the polymer electrolytes are thermally assisted and can be described by Arrhenius law. The conductivity variant has been justified via the Rice and Roth model in which the number of free ions per unit volume, mobility and diffusion coefficient of free ions were obtained. [ABSTRACT FROM AUTHOR]

Films of polyethylene oxide (PEO) based polymer electrolyte were prepared by the technique of solution casting. Propylene carbonate (PC) was employed as the plasticiser and lithium trifluoromethanesulfonate (LiCF3SO3) was used as the doping salt. The highest room temperature conductivity achieved in PC plasticised system is 8·12 × 10-6 S cm-1. The effects of PC on the frequency dependent dielectric properties of PEO based electrolytes were also investigated by impedance spectroscopy, in the temperature range from 300 to 343 K. The relaxation time for the ionic charge carriers τ was obtained from the variation of loss tangent (tanδ) as a function of frequency at various temperatures for sample with highest conductivity value. The linear behaviour of temperature dependence of τ with regression value 0·91 could be described by Arrhenius law. The results of ac conductivity were discussed with existing theoretical models to elucidate the mechanism of conductance in the prepared electrolyte system. [ABSTRACT FROM AUTHOR]

Information about the International Conference on Functional Materials and Devices (ICFMD-2008) that was held in Kuala Lumpur, Malaysia is presented. It discussed various aspects of functional materials and devices related to medical. It included the presentation of the Young Scientist Awards, as well as lively scientific discussions.