Evaluation of Li Electrodeposition into Al from LiCl–KCl Electrolyte

Abstract

This study investigated the effects of temperature and the current density on the production of an Al–Li master alloy using electrolysis. The current efficiency and the specific energy consumption were calculated according to Faraday’s law to determine optimal conditions for production of the Al–Li master alloy. Solid aluminum and graphite were used as the cathode and the anode, respectively. The LiCl–KCl eutectic molten salt was used as a lithium-containing electrolyte. Different current densities were applied to obtain the optimum condition. In addition, different temperatures were investigated at the optimum current density during the deposition of lithium. Scanning electron microscopy, optical microscopy, and the X-ray diffraction analysis were used to investigate the microstructure and phase compositions. Atomic absorption spectroscopy was used to measure the existing lithium. The results showed that electrolysis at 620°C and a current density of 0.9 A/cm2 at 4 V for 3 h leads to the formation of an Al–17.43 wt % Li master alloy. The current efficiency and the specific energy consumption for the optimum conditions were found to be 96% and 16.08 kWh/kg, respectively.