In this presentation we elucidate the structure-dynamics-property relationships that underpin the performance of ion containing polymers as membranes in electrochemical energy storage and delivery technologies.We leverage quasielastic neutron scattering to quantify the dynamics within the polymeric membrane on the nano- to picosecond time scales over length scales of few angstroms to several nanometers in a series of model single ion conducting polymers,where only the cation is mobile,with systematic variations in the spacing between the ions,degree of ionization,and the type of ion.