Direct electrochemical extraction of metallic Li from a molecular liquid-Based electrolyte under ambient conditions

The high chemical activity of metallic Li hinders its efficient electrochemical extraction at low temperatures, necessitating the use of energy- and cost-intensive methods such as vacuum thermal reduction or electrodeposition from ionic-liquid and molten-salt electrolytes. Herein, we report the direct room-temperature electrowinning of metallic Li from a simple low-cost electrolyte, namely a solution of LiCl in dimethylacetamide (DMAc), determine the optimal concentration of LiCl, and examine the redox processes in the optimized system. Potentiostatic deposition on high-purity Al is shown to induce solid-state cathode alloying and thus produce a uniform, flat, and dense coating of a LiAl master alloy comprising spherical clusters formed by LiAl alloy nanosheets. Finally, the direct smelting of electrodeposited films is proposed as a method of rapidly realizing the thin film to bulk transformation of electrodeposited materials to stabilize metallic Li and form bulk Li-based alloys. Thus, this study provides a basis for the continuous, low-cost, sustainable, and fast electrochemical production of bulk active metals or their alloys.

Automated summary

This study reports the direct electrowinning of metallic Li from a low-cost electrolyte (LiCl in dimethylacetamide) at room temperature, determines the optimal LiCl concentration, and explores the redox processes in the optimized system. It is suggested that the direct smelting of electrodeposited films can rapidly transform thin films to bulk materials, stabilizing metallic Li and forming bulk Li-based alloys.