Dendrite-Free and Micron-Columnar Li Metal Deposited from LiNO₃-Based Electrolytes

Rechargeable Li-metal anodes have received abundant attention for high-energy-density batteries. A solid electrolyte interphase (SEI) plays a significant role in regulating the Li+ deposition/stripping process. Aimed to solve detrimental Li deposition with a dendritic and mossy morphology, herein, dendrite-free columnar Li deposition in micron size is constructed via creatively adopting a LiNO3-based electrolyte even at a high current density (2 mA cm–2) and areal capacity (4 mAh cm–2). N-rich inorganic SEI (Li3N and LiNxOy) with superior Li+ conductivity is formed on Li deposition, which enables remarkable reversibility and high average Coulombic efficiency (CE) even over 240 cycles. A Li∥LiFePO4 cell delivers excellent cycling stability over 700 cycles with a capacity fading rate of merely 0.022% per cycle. This work provides a way to regulating columnar Li deposition via N-rich SEI coordination and developing electrolyte formulations for secondary Li-metal batteries.