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Carbonaceous anode materials in lithium ion rechargeable cells experience irreversible capacity, mainly due to a consumption of lithium in the formation of surface passive films. The stability and kinetics of lithium intercalation into the carbon anodes are dictated by these films. The nature, thickness and morphology of these films are in turn affected by the electrolyte components, mainly the solvent constituents. In t h s work, the films formed on graphite anodes in low temperature electrolytes, i.e., solutions with different mixtures of alkyl carbonates and low-viscosity solvent additives, are examined using electrochemical impedance spectroscopy (EIS) and solid-state 'Li NMR techniques. In addition, other ex-situ studies such as x-ray diffraction (XRD), transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) were carried out on the graphite anodes to understand their microstructure. * Author to whom all correspondence may be addressed.