Lithium – Ion Batteries: Identifying the Perfect Polymer Electrolyte!

 

Topic  48
Main supervisor Michael Ohl (m.ohl@fz-juelich.de)
MLZ institution FZJ
Local supervisor 1
Nicholas Bucher
Institution
Varta Microbattery GmbH
Local supervisor 3
Institution
Local supervisor 3
Institution
Local supervisor 4
Institution
Title
Lithium – Ion Batteries: Identifying the Perfect Polymer Electrolyte!
Description

Batteries play an important role in our daily life with a variety of applicants. To this day a lot of money had been put in research to develop effective batteries and especially research to find the right materials in try and error attempts. Polymer electrolytes are widely studied for their promise to improve batteries safety. Here Poly-ethylene oxide (PEO) is widely used as polymer matrix due to its high conductivity up to 10-2S/cm. Also other candidates showed promising conductivities and characteristics as battery devices. However, in PEO based Lithium batteries, it is generally accepted that the charge transfer transportation mechanism of the Li+ is directly dependent on the segmental (and backbone) motions of the polymer. While the segmental motions of the polymer can make the conductivity process of Li+ faster. With quasi – elastic Neutron scattering (QENS) we can probe proton dynamics in a time range and length scale corresponding segmental motions of polymers and at the same time accessible for state of the art MD simulations. In MD simulations we see both, the Lithium and polymer motions. Now, when achieving reasonable agreement between experimental data and MD simulations, our microscopic picture of the Lithium movement is confirmed. This new understanding will put us in a position to better tailor new specimen of polymer electrolytes for further improved batteries.
The potential candidate will study a variety of Electrolyte e.g. polymers (not limited to PEO) / Li – ion batteries with several in-house techniques and QENS to identify proper candidates for optimized batteries and validate the results with in-house experiments and Neutron scattering techniques.