High reversible Li plating and stripping by in-situ construction a multifunctional lithium-pinned array

Abstract

Lithium metal is the most promising anode candidate because of its ultrahigh theoretical specific capacity. Unfortunately, its high reactivity, uncontrolled dendrites, "dead lithium" formation, and infinite volume expansion hinder its commercial application. Herein, by in-situ constructing a multifunctional lithium-pinned array (m-LPA) endowed with functions of lithiophilicity, zoning effect and riveting effect on a surfacely phosphorized three-dimensional (3D) copper foam, a high reversible Li plating/stripping electrochemistry can be achieved. Benefiting from the m-LPA, lithium can uniformly plate/strip both on the surface and in the inner space of the 3D skeletons with improved morphology. Consequently, a high Coulombic efficiency (similar to 98.41%) could be achieved at 1 mA cm(-2) with 1 mA h cm(-2) for over 600 cycles (1200 h). Moreover, at a higher current density of 10 mA cm(-2) with 0.5 mA h cm(-2), a symmetric cell with m-LPA@Li electrode could still stably cycle for 900 cycles. Finally, a full cell coupled with LiFePO4 cathode displayed excellent rate performance with a lower overpotential. The conception and strategy of m-LPA, which were first proposed here, are a promising way to realize large-scale application of Li anode.