Most studies mentioned above on mixtures of ionic liquids and organic carbonates paid particular emphasis on improved macroscopic properties such as safety performance and enhanced electro-chemical properties, while often neglecting micro structures and ion-ion interactions . Further studies on microstructures and ion-ion interactions of ionic liquids at molecular level, as pure compounds or in the presence of dissolved species, is useful to design of suitable ionic liquids for a particular application, and this facilitates the selection of an optimum conditions of transport and thermodynamic properties. The ability to form mixtures of ILs with organic carbonates and other solvents has become increasingly important, and this is heavily influenced by the nature of the electrostatic interactions that take place. Inspired by that work, therefore, the current work unravels the microstructures and ion-ion interactions of ionic liquids at molecular level, both as pure components and in the presence of dissolved carbonate solvents, critically comparing the impact of adding carbonate (EC/DMC) co-solvents on the ion-ion interactions and the structural properties of the corresponding blends using 1M LiTFSI as conducting lithium salt.