Lithium metal batteries using a lithiophilic oxidative interfacial layer on the 3D porous metal alloy media†

Abstract

Various lithium-infused metal anodes based on pure nickel foam, recognised for their superior properties, have been developed for application in lithium batteries. However, pure nickel foam exhibits significant reactivity with molten lithium during the infusion processes, such as coating and impregnation. In this study, a high-performance and ultra-stable lithium-infused metal anode (LI-NAFA) is synthesised through a simple oxidation treatment of nickel–chromium–aluminium (Ni–Cr–Al) alloy foam (NAF) at 900 °C in an air atmosphere. This approach effectively mitigates the material's reactivity with molten lithium, thereby enhancing the stability of the resulting anode. A layer of several hundred nanometers is generated, which converts the NAF surface from lithiophobic to lithiophilic. Additionally, the layers formed during oxidation enhance the molten lithium stability. A full cell test employing LI-NAFA showed stability during the molten lithium infusion and cycle performance. A full cell with pure lithium was also tested for comparison. The notable enhancement in performance can be ascribed to the excellent electrical conductivity of the NAF and improved cycling stability of lithium ions facilitated by uniform charge distribution. Following cell discharge, the LI-NAFA showed no formation of lithium dendrites and a reduction in dead lithium. LI-NAFA holds great potential for developing high-performance lithium metal batteries because of its favourable fabrication process and excellent cycling stability.