Highly Li⁺ Conductive Artificial Solid Electrolyte Interphase for Lithium Metal Batteries

Poor reversibility of the Li anode and uncontrolled Li dendrite growth lead to the low Coulombic efficiency and serious security risks, which hinder the practical application of lithium (Li) metal batteries. Herein, we report an artificial solid electrolyte interphase (SEI) strategy for repressing Li dendrite growth and facilitating uniform Li deposition. The N-vinyl carbazole (NVK) was polymerized on the Li anode surface to form artificial SEI film. Such SEI film generates highly Li⁺ conductive lithium nitride (Li₃N) to boost uniform Li⁺ flux and then facilitates uniform Li deposition on the Li anode. Therefore, the Li||Li symmetric cells showed excellent cycling performance with 350 cycles at 1.0 mA/cm². Meanwhile, the Li||LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622) batteries also achieved a higher cycling performance with a capacity retention of 87.5% after 150 cycles. This work provides a simple and effective strategy to solve the problem of dendrites in the Li metal battery.