Wave-layered dendrite-free lithium deposition with unprecedented long-term cyclability

Abstract

Lithium dendrite growth on the anode during cycling leads to poor stability and severe safety issue, hampering long-term cycle for high-energy batteries. Herein, we firstly found that dendrite-free Li can be deposited layer-by-layer on the surface of lithiophilic Li3N (001) or (111) facet, and then synthesized a composite electrode of Li3N involving a high fraction of (001) facet on porous carbon cloth (P-CC), wherein Li3N in-situ formed by immersing of P-CC in a solution of molten Li, offering outstanding electrochemical and battery performance. Unique waved-layered dendrite free Li deposition has been detected during the Li-plating/stripping process. This P-CC/Li3N/Li anode exhibits a cycle lifespan as long as 2000 h with low overpotential of ∼20 mV at 1 mA cm−2 in a symmetrical cell, which overwhelms all similar systems reported so far. Attractively, long-term operations of 35, 200, and 400 h at 10 mA cm−2 can be achieved at temperatures of −10, 25, and 50 °C, respectively. Both experimental and density functional theory calculations confirm that the P-CC/Li3N serves as an appropriate host for Li infusion through an efficient ion conductive network, inducing the nucleation and growth of metallic lithium.