Polymer electrolytes: The importance of ion-ion interactions in diffusion dominated behavior

Monte Carlo simulations combined with analytic results based on the dynamically disordered hopping model are used to show that even in the presence of ion-ion interactions, the conductivity of polymer electrolytes is diffusion dominated. Coulomb interactions between charge carriers do result in some collective correlations that affect the conductivity, as evidenced by deviations from the Nernst Einstein equation, but the action of these interactions on the diffusivity overshadows these effects. Furthermore, these results show that renewal limited behavior (the diffusion coefficient depends linearly on the host's renewal rate) can persist even in the presence of these interactions. These studies help resolve the role ion-ion interactions play in renewal dominated behavior.