Organosilane based artificial solid electrolyte interface layer for stable metallic lithium anode

• Organosilane based A-SEI coating strategy employed in stabilizing lithium anode. • Epoxide functional sites in organosilane regulates the uniform deposition of lithium. • Li/Li symmetric cell using GPS-Li delivers an overpotential of 40 mV at 4 mA cm −2. • Uniform Li plating/striping process over 800 cycles observed in GPS-Li symmetric cell. • NMC/GPS-Li renders higher specific capacity @ 2C rate, when compared to NMC/P-Li cell. Owing to its high specific capacity, lithium metals are considered as potential anode candidate for high energy density lithium-sulfur (Li-S)/lithium-oxygen (Li-O 2 ) batteries. However, uncontrollable lithium dendrite growth makes the spontaneously formed solid electrolyte interface layer (SEI) in lithium metal anode (LMA) fragile, preventing cyclic Li plating/stripping process, thereby limiting its usage in high energy density batteries. In this work, we demonstrate a novel organosilane coating strategy, resulting in the formation of artificial SEI (A-SEI) promoting stable operation of LMA. The presence of epoxide moieties in the coated organosilane induces uniform Li + electrodeposition, thereby effective control over dendrite growth. Symmetric Li/Li cells fabricated using silane coated lithium metal renders stable cycling with the constant over potential value of 40 mV over 800 cycles at the current rate of 4 mA cm −2 , when compared to pristine lithium anode. Furthermore, the NMC/Li cell fabricated using modified LMA showed relatively better charge/discharge capacity values of 116/115 mAhg −1 coupled with the coulombic efficiency of 99.1 %, after 200 cycles at 2C in comparison to pristine lithium based cell (charge/discharge capacity, 91/90 mAhg −1 @2C after 200 cycles). Thus, the proposed A-SEI coating strategy enrooted a new pathway for the development of lithium anodes with outstanding electrochemical characteristics.