The Coulombic efficiency of lithium deposition/stripping can be improved while also substantially preventing lithium dendrite formation and growth using particular electrolyte compositions. Embodiments of the electrolytes include organic solvents and their mixtures to form high-quality SEI layers on the lithium anode surface and to prevent further reactions between lithium and electrolyte components. Embodiments of the disclosed electrolytes further include additives to suppress dendrite growth during charge/discharge processes. The solvent and additive can significantly improve both the Coulombic efficiency and smoothness of lithium deposition. By optimizing the electrolyte formulations, practical rechargeable lithium energy storage devices with significantly improved safety and long-term cycle life are achieved. The electrolyte can also be applied to other kinds of energy storage devices.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with Government support under Contract DE-AC05576RLO1830 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.