Lithium dendrite suppression and cycling efficiency of lithium anode

We propose a novel binary electrolyte of lithium bis(fluorosulfonyl)imide/1,3-dioxolane, that exhibits excellent performance for the suppression of lithium-dendrite growth and stability against lithium metal. With 2.5 M lithium bis(fluorosulfonyl) imide in 1,3-dioxolane, long short-circuit onset-times of 72.3 and > 190 h are observed in Li/Li cells polarized at galvanostatic current densities of 1.0 and 0.5 mA cm(-2), respectively. The coulombic efficiencies for the repeated Li plating/stripping in the 2.5 M electrolyte at 1.0 and 0.5 mA cm(-2) are as high as 99.0% and 99.5%, respectively. The electrolyte structure is changed with an increase in the concentration speculated from Raman spectra, which enables the reactivity toward lithium metal to be lowered.