Bifunctional group additives induce solvent-based structural reconfiguration of electrolytes for high-performance lithium-metal batteries

The lithium-metal batteries (LMBs) have attracted attention due to high energy density and wide application prospects. However, issues such as the uncontrolled growth of lithium dendrites on the lithium metal surface and the instability of the solid electrolyte interphase pose safety hazards to LMBs. In this study, we addressed these challenges by adding Propargyl methanesulfonate (PMS) to the electrolyte, which led to the reconstruction of the solvation structure of Li+. PMS facilitates the formation of a smooth and stable solid electrolyte interface on the Li anode surface, suppressing the uncontrolled growth of dendrites. Additionally, the observation of dendrite growth is conducted using in-situ optical microscopy. Furthermore, PMS decomposes on the Li anode to form sulfur-containing compounds, promoting the shuttle of Li+ and enhancing the cycling stability of the cell. The assembly of a Li/LiNi0.8Co0.1Mn0.1O2 full cell is used to validate further that adding PMS enables stable and reversible cycling of LMBs.