Recovery of LiCoO2 and graphite from spent lithium-ion batteries by molten-salt electrolysis

Jin Feng; Beilei Zhang; Pin Du; Yahong Yuan; Mengting Li; Xiang Chen; Yanyang Guo; Hongwei Xie; Huayi Yin

doi:10.1016/j.isci.2023.108097

Recovery of LiCoO₂ and graphite from spent lithium-ion batteries by molten-salt electrolysis

iScience. 2023 Sep 30;26(11):108097. doi: 10.1016/j.isci.2023.108097. eCollection 2023 Nov 17.

Authors

Jin Feng¹, Beilei Zhang², Pin Du¹, Yahong Yuan¹, Mengting Li¹, Xiang Chen¹, Yanyang Guo¹, Hongwei Xie¹, Huayi Yin^{1

3

4}

Affiliations

¹ Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education, School of Metallurgy, Northeastern University, 11 Wenhua Road, Heping District, Shenyang 110819, P.R. China.
² School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, P.R. China.
³ Key Laboratory of Data Analytics and Optimization for Smart Industry, Ministry of Education, Northeastern University, Shenyang 110819, P.R. China.
⁴ School of Resource and Environmental Science, Wuhan University, 299 Bayi Road, Wuhan, Wuchang District 430072, P.R. China.

Abstract

The recovery of spent lithium-ion batteries has not only economic value but also ecological benefits. In this paper, molten-salt electrolysis was employed to recover spent LiCoO₂ batteries, in which NaCl-Na₂CO₃ melts were used as the electrolyte, the graphite rod and the mixtures of the spent LiCoO₂ cathode and anode were used as the anode and cathode, respectively. During the electrolysis, the LiCoO₂ was electrochemically reduced to Co, and Li⁺ and O^2- entered into the molten salt. The O^2- was discharged at the anode to generate CO₂ and formed Li₂CO₃. After electrolysis, the cathodic products were separated by magnetic separation to obtain Co and graphite, and Li₂CO₃ was recovered by water leaching. The recovery efficiencies of Li, Co, and graphite reached 99.3%, 98.1%, and 83.6%, respectively. Overall, this paper provides a simple and efficient electrochemical method for the simultaneous recovery of the cathode and the anode of spent LiCoO₂ batteries.

Keywords: Electrochemical energy storage; Energy resources; Engineering.