In-Situ Solid Electrolyte Interphase from Vertical Nise2 Nanoflake Arrays on Carbon Cloth for Dendrite-Free Li Metal Anodes

Lithium metal is considered as the next-generation anode material to realize high-energy-density batteries, owing to its high specific capacity and low negative potential. Unfortunately, the practical application of Li metal anode has been severely hindered by sharp Li dendrites and low Coulombic efficiency, which eventually give rise to shortened cycling lifespan and even potential short circuit risks. Herein, a novel 3D current collector is prepared by in-situ growth of vertical NiSe 2 nanoflake arrays on carbon cloth (NiSe 2 /CC) to regulate the homogeneous deposition of Li. The as-synthesized NiSe 2 nanoflakes deliver good reactivity with Li metal and form Li 2 Se-enriched solid electrolyte interphase (SEI) during the initial activation process, thus leading to high ionic conductivity. Simultaneously, the sufficient deposition sites provided by the well-distributed NiSe 2 nanoflake arrays reduce the local current density and ameliorate uniform Li-ion flux of the current collector, so that uniform Li stripping/plating behavior is significantly promoted. Consequently, dendrite-free Li deposition behavior of the NiSe 2 /CC current collector with an enhanced Coulombic efficiency of ~99.5% for 300 cycles are demonstrated, and longer cycling lifespan over 700 h in the Li@NiSe 2 /CC symmetrical cell are achieved, as well as the excellent cycling stability and rate capacity in LiFePO 4 full cells. Therefore, such a strategy to modify 3D framework with superior performance is expected to construct high-stability and dendritic-free Li metal anode for advanced Li metal batteries