Two Birds with One Stone: Using Indium Oxide Surficial Modification to Tune Inner Helmholtz Plane and Regulate Nucleation for Dendrite-free Lithium Anode

Small Methods. 2022 May;6(5):e2200113. doi: 10.1002/smtd.202200113. Epub 2022 Mar 11.

Abstract

Lithium metal has been considered as the most promising anode material due to its distinguished specific capacity of 3860 mAh g-1 and the lowest reduction potential of -3.04 V versus the Standard Hydrogen Electrode. However, the practicalization of Li-metal batteries (LMBs) is still challenged by the dendritic growth of Li during cycling, which is governed by the surface properties of the electrodepositing substrate. Herein, a surface modification with indium oxide on the copper current collector via magnetron sputtering, which can be spontaneously lithiated to form a composite of lithium indium oxide and Li-In alloy, is proposed. Thus, the growth of Li dendrites is effectively suppressed via regulating the inner Helmholtz plane modified with LiInO2 to foster the desolvation of Li-ion and induce the nucleation of Li-metal in two-dimensions through electro-crystallization with Li-In alloy. Using the In2 O3 modification, the Li-metal anode exhibits outstanding cyclic stability, and LMBs with lithium cobalt oxide cathode present excellent capacity retention (above 80% over 600 cycles). Enlightening, the scalable magnetron sputtering method reported here paves a novel way to accelerate the practical application of the Li anode in LMBs to pursue higher energy density.

Keywords: Li metal anodes; dendrite-free Li anodes; frequency radio magnetron sputtering; inner Helmholtz plane; ultra-lithiophilic indium oxide.