Molten LiI/AlCl3 with different molar ratios of LiI to AlCl3 were prepared and characterized by Raman spectroscopy, thermal analysis, and impedance measurements. The LiI/AlCl3 adducts melt at 70-80 degreesC and the Raman spectrum indicates that a variety of haloaluminates exist in the system. The 1:1 adduct has the highest ionic conductivity, 2x10(-6) S/cm at 25 degreesC, and the conductivity increases dramatically as the temperature is increased. Molecular dynamics (MD) simulations suggest that several haloaluminates are present in the adducts. Ab initio calculations were carried out on the species that were predicted by MD simulations and these results were compared with Raman spectra, and good agreement was obtained. Several-ns-long MD simulations allowed us to study the conductivity and relaxation processes in the 1:1 and 1:2 melts at higher temperatures.