Stable lithium metal anode enabled by high-dimensional lithium deposition through a functional organic substrate

Abstract

The growth of lithium dendrites severely restricts the development of lithium metal batteries. In order to achieve the goal of dendrites-free lithium in principle, it is crucial and urgent to control nucleation and growth of lithium. Here, a functional organic layer of perylene-3, 4, 9, 10-tetracarboxydiimide-lithium (PTCDI-Li) is built on the lithium anode surface by in-situ chemical reaction of PTCDI and Li metal. PTCDI-Li, with high surface energy (-10.19 eV) and low diffusion barrier (0.89 eV), efficiently promotes disk-shaped high-dimensional nucleation by regulation of lithium ion flux upon lithium plating, leading to a dendrites-free morphology. When operating under a relatively high current density of 10 mA cm−2, the Li | Li symmetrical cells with PTCDI-Li exhibit outstanding cyclic stability for 300 hours with ultralow overpotential of 400 mV, superior to the most of the reported lithium anode. The corresponding PTCDI-Li batteries show high specific capacity and enhanced cycle life. We anticipate that this strategy of regulation of lithium deposition from one-dimensional to high-dimensional opens a new horizon in the development of dendrites-free Li anodes.