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This paper reports dielectric spectroscopic studies completed by electrochemical measurements in combination with DSC and PFG-NMR investigations to study the charge carrier transport in gel electrolytes, which were prepared by photoinitiated polymerization of oligo(ethylene glycol)23 dimethacrylate [(EG)23DMA] in the presence of oligo(ethylene glycol)11dimethyl ether [(EG)11DME] as plasticizer and LiCF3SO3. The resulting films show a glass transition at about −60 °C and the melting of the plasticizer around −12 °C. Below the glass transition two relaxation processes were observed by dielectric spectroscopy, which most likely are to be related to the γ relaxation of the EG groups and the β relaxation of the methacrylate groups. The high-temperature behavior of the dielectric response is dominated by the conductivity, which is weakly dependent on the frequency in this temperature range. The permittivity goes through a maximum at room temperature and decreases with further enhancement of the temperature in connection with an increase in ionic aggregation indicated by growing deviations from the Nernst−Einstein relationship. These deviations expressed as a Haven ratio are discussed as the contribution of bounded species that do not take part in the conductivity to the overall diffusivity, either by an enlarged content of these species, c b, or by an enhancement of their self-diffusivity, D b.

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