Electrochemical lithium recovery process via state-of-charge control (SoC) for efficient lithium recovery from concentrated seawater

Park, Harang; Lee, Jaehan

doi:.0..

DOI: https://doi.org/10.4491/eer.2024.440

Electrochemical lithium recovery process via state-of-charge control (SoC) for efficient lithium recovery from concentrated seawater

Harang Park, and Jaehan Lee^†

Department of Biological and Chemical Engineering, College of Science and Technology, Hongik University, 2639 Sejong-ro, Sejong-si 30016, Republic of Korea

Corresponding Author: Jaehan Lee ,Tel: +82-44-860-2514 , Fax: +82-44-866-6940 , Email: ljh0322@hongik.ac.kr

Received: July 18, 2024; Accepted: October 8, 2024.

ABSTRACT

With the increasing demand for lithium driven by its widespread use in various industries, researchers are exploring ways to expand the lithium supply. This study proposes an electrochemical lithium recovery (ELR) system using the state-of-charge (SoC) control for extracting lithium from the actual concentrated seawater from the salt manufacturing process. In cyclic stability tests where the 60% SoC level of the LiMn2O4 (LMO) electrode was adjusted, the charge-discharge retention rate showed approximately two times higher performance compared to 100% SoC after 30 cycles. In particular, it was observed that the amount of extracted lithium from source water at 60% SoC is 8 times higher, consuming 89% less energy than at 100% SoC. The study also confirmed the physical stability of the LMO electrodes by X-ray diffraction analysis, showing relatively better results at 60% SoC operation. Based on these results, the SoC control operation in the ELR system has the capacity to enhance both the stability and efficiency of lithium extraction from concentrated seawater.

Keywords: Concentrated seawater | Electrochemcial lithium recovery | Lithium manganese oxide | State-of-Charge control