<p>Magnesium-lithium alloys have emerged as promising lightweight materials for aerospace applications due to their outstanding specific strength and low density. In this study, an aluminum coating was electrodeposited onto a commercial LA103Z magnesium-lithium alloy using an environmentally friendly aluminum chloride-triethylamine hydrochloride (AlCl₃-Et₃NHCl) room-temperature ionic liquid electrolyte to enhance its corrosion resistance. The aluminum coating serves as a protective layer that improves the surface functionality and extends the service life of the magnesium-lithium alloy. The electrodeposition mechanism, surface morphology, microstructure, and corrosion behavior of the aluminum coatings were systematically investigated using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and electrochemical analysis. The results reveal that aluminum electrodeposition in the AlCl₃-Et₃NHCl electrolyte follows a three-dimensional instantaneous nucleation mechanism, with the reduction of electroactive Al₂Cl₇⁻ ions to metallic aluminum being diffusion-controlled. At a deposition potential of − 0.4&#xa0;V, the resulting aluminum coating exhibited a smooth, compact, and uniform morphology. However, as the deposition potential shifted to more negative values, the coating surface became rougher, accompanied by crack formation and increased grain size. Furthermore, higher deposition temperatures led to the development of coarser and less uniform grains. The optimal coating performance was achieved at a deposition potential of − 0.4&#xa0;V and a temperature of 303&#xa0;K, where the aluminum layer displayed fine grains, low surface roughness, and superior corrosion resistance.</p>