The aim is to understand the ion conduction mechanism in polymer electrolytes with added nanoparticles and/or ionic liquid. In "ordinary" polymer electrolytes it has been shown that the ionic conductivity is closely related to the segmental polymer dynamics and the conduction mechanism is reasonably well understood. However, in the case of nanocomposite polymer electrolytes (i.e. with added nanoparticles) and polymer gel electrolytes (i.e. with an added low molecular weight solvent) the conduction mechanism and the role of polymer dynamics are less understood. The reason for this is partly the difficulty to use dielectric spectroscopy to determine the segmental polymer relaxation, due to that it becomes hidden in the strong conductivity contribution. However, we have now improved the method to accurately subtract the dc conductivity in the imaginary part of the permittivity, and in that way make the otherwise hidden polymer dynamics visible. Thus, it will now be possible to determine the role of segmental polymer dynamics for the conduction process also in these types of polymer based electrolytes. The findings are expected to provide insights into how the conduction mechanism is altered compared to "ordinary" polymer electrolytes and how mechanical and conductivity properties can be optimized in future solid electrolytes for electrochemical applications. This implies that the project should contribute to the long-term goal of "green" energy and a sustainable society.
Professor vid Chalmers, Physics, Condensed Matter Physics
Funding years 2012–2014