Theoretical and experimental analyses of the thermodynamic properties of charged polymers have provided insights into how to control nanostructures via electrostatic interactions and improve the ionic conductivity without compromising mechanical strength, which is crucial for practical applications. In this talk, I would like to discuss methods to control the self-assembly and ion diffusion behavior of charged block copolymers by varying the type of tethered ionic moieties, local concentration of embedded ions with controlled electrostatic interactions, and ion dissociation strength nanoscale morphology. I discuss with particular emphasis on the structure–transport relationship of charged block copolymers using various ionic additives to control the phase behavior electrostatically, as well as the ion-transport properties.