||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 investigated 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 10-3 S/cm. 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 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 taylor new specimen of polymer electrolytes for further improved batteries. The potential candidate will simulate a variety of Electrolyte e.g. polymers / Li – ion batteries with MD simulation to find proper candidates for optimised batteries and validate the results with in-house experiments and Neutron scattering techniques.