The corrosion and discharge behavior of high-performance Mg-7Li-1Y alloy as anode for Mg-air batteries

In this work, the microstructure, corrosion resistance and discharge properties of the as-extruded Mg-7Li-1Y alloy are systematically studied. The results show that the as-extruded Mg-7Li-1Y alloy is mainly composed of the alpha-Mg and beta-Li phases with an obvious bimodal microstructure. Although the as-extruded Mg-7Li-1Y alloy exhibits relatively poor corrosion resistance with the impedance value of only 163.68 Omega middotcm2 and the corrosion current density of 9.5 x 10-5 A/cm2 in 3.5% NaCl solution, it possesses an outstanding discharge performance with a discharge voltage of 1.35 V and a high anode utilization rate of 59% at the current density of 10 mA/cm2. Meanwhile, it has a high specific energy density with about 1870 mWhmiddotg-1 at the current density of 10 mA/cm2. The analysis indicates that the beta-Li phase, low hydrogen evolution re-action and the unique morphologies of discharge products are responsible for the improvement of the electrochemical activity and the discharge performance of the Mg-7Li-1Y alloy.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In this work, the microstructure, corrosion resistance, and discharge properties of the as-extruded Mg-7Li-1Y alloy were studied. The alloy exhibited a bimodal microstructure mainly composed of alpha-Mg and beta-Li phases. Despite poor corrosion resistance, it showed remarkable discharge performance with a discharge voltage of 1.35 V and a high anode utilization rate of 59% at a current density of 10 mA/cm2. The unique morphologies of discharge products and the presence of beta-Li phase contributed to the improved electrochemical activity and discharge performance.