Vinylene carbonate–LiNO3: A hybrid additive in carbonic ester electrolytes for SEI modification on Li metal anode

• Vinylene carbonate (VC)–LiNO3 was employed in carbonic ester electrolytes for the first time.
• One of the main components in modified SEI film by LiNO3 is Li3N which is obviously distinct from the ones generated in ether-based electrolytes.
• An efficiency of Li plating/stripping near to 100% and a uniform morphology of cycled Li with spherical deposits were obtained.

A hybrid solid electrolyte interphase (SEI) formation additive, vinylene carbonate (VC)–LiNO3, was investigated in carbonic ester electrolytes. An efficiency of lithium plating/stripping as high as nearly 100% and spherical Li deposits were obtained. The electrochemical impedance spectroscopy (EIS) results demonstrate that the modified SEI is very stable and of good conductivity. X-ray photoelectron spectroscopy (XPS) results indicate that VC–LiNO3 dominates the surface chemistry of the Li anode. The formation of Li3N in the SEI contributes to the enhancement of the anode performance.