Dendrite-Free and Stable Lithium Metal Anodes Enabled by an Antimony-Based Lithiophilic Interphase

Rechargeable lithium metal batteries are of tremendous interest due to the high theoretical capacity and low reduction potential of lithium metal anode. However, the formation of unstable solid electrolyte interphase (SEI) results in lithium dendrite growth and low Coulombic efficiency during Li plating/stripping processes. Herein, we report an effective strategy to stabilize Li metal anode by in situ constructing antimony-based lithiophilic interphase on Li anode (Sb–Li) using antimony triiodide-tetrahydrofuran (THF) solution. The antimony-based lithiophilic interphase is composed of amorphous antimony and lithium compounds, revealed by in-depth X-ray photoelectron spectroscopy. The Sb–Li anode enables dendrite-free Li deposition in both ether- and ester-based electrolytes. As a result, as-assembled lithium–sulfur (Li–S) batteries with Sb–Li anode exhibit an initial capacity of 915 mAh g–1 at 1.0 C and a capacity retention >83% after 400 cycles. Operando Raman analysis confirmed that the antimony-based lithiophilic interphase can prevent parasitic side reactions, and also relieve the shuttle effect of polysulfides. Furthermore, Sb–Li|LiFePO4 cells have also realized high rate performance and stable cyclability. We expect this effective strategy for stabilizing Li metal anode will provide a valuable route to develop high-energy Li metal batteries.