Direct electrochemical extraction of metallic Li from a molecular liquid–Based electrolyte under ambient conditions. (10th February 2023)

• Record Type: Journal Article
• Authors: Zhang, Haoyu; Zhang, Baoguo; Ai, Bing; Pan, Kefeng; Zhang, Weimin; Zhang, Lipeng; Shi, Zhongning
• Is Part Of: Electrochimica acta. Volume 441(2023)
• Publication Date: 2023-02-10
• Subjects: Li recycling -- Active metal -- Molecular liquid -- Bulk electrodeposition -- Solvometallurgy; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2023.141845
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Direct electrodeposition of Li from a molecular liquid–based electrolyte is achieved. A solution of LiCl in dimethylacetamide is used as the electrolyte. Li is deposited as LiAl master alloy produced via solid-state cathode alloying. Strategy for thin film-to-bulk conversion of electrodeposited materials is proposed. Guidance for continuous electrodeposition of bulk active metals is provided. Abstract: 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.