Role of chain architecture and composition on dynamics and ionic solvation in polyether-based electrolytes*

In recent years a great number of new polymer electrolytes have been developed towards improved performance and stability of energy storage devices. These new materials typically include polyether moieties to facilitate efficient ion transport. However, the presence of additional non-conducting groups influences the ability of polyethers to solvate ions and hopping between these solvation sites. We have examined a number of polyether-based electrolytes in linear, block, graft, and blend configurations to explore how chemical and physical interactions between different components affects ionic conductivity. Using a combination of impedance spectroscopy, vibrational spectroscopy, and atomistic simulations, we gain insight into the degree of ion conductivity, ionic interactions, and polymer dynamics of these materials. Both the polymer-polymer interaction strength and segmental mobility of non-solvating components show an effect on the overall conductivity and connectivity of ion solvation sites. These findings highlight the need for more complete models to account for various length scales of interaction in these nonuniform material systems.