Understanding the effect of nonmetallic impurities in regenerated cathode materials for lithium-ion battery recycling by tracking down impurity elements

Mincheol Beak; Jangho Park; Sanghyuk Park; Seongdeock Jeong; Jingu Kang; Woosung Choi; Won-Sub Yoon; Kyungjung Kwon

doi:10.1016/j.jhazmat.2021.127907

Understanding the effect of nonmetallic impurities in regenerated cathode materials for lithium-ion battery recycling by tracking down impurity elements

J Hazard Mater. 2022 Mar 5:425:127907. doi: 10.1016/j.jhazmat.2021.127907. Epub 2021 Nov 26.

Authors

Mincheol Beak¹, Jangho Park¹, Sanghyuk Park², Seongdeock Jeong¹, Jingu Kang³, Woosung Choi⁴, Won-Sub Yoon⁴, Kyungjung Kwon⁵

Affiliations

¹ Department of Energy & Mineral Resources Engineering, Sejong University, Seoul 05006, Republic of Korea.
² Autonomous Intelligent Unmanned Flying Vehicles Institute, Sejong University, Seoul 05006, Republic of Korea. Electronic address: shpark@sejong.ac.kr.
³ Young Poong Research Institute of Metallurgy, Seokpo, Gyeongbuk 36272, Republic of Korea.
⁴ Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea.
⁵ Department of Energy & Mineral Resources Engineering, Sejong University, Seoul 05006, Republic of Korea. Electronic address: kfromberk@gmail.com.

PMID: 34872036
DOI: 10.1016/j.jhazmat.2021.127907

Abstract

The regeneration of cathode materials would be the highest value-added direction in lithium-ion battery (LIB) recycling research. Li[Ni_xMn_yCo_z]O₂ (NMC) is regenerated from actual industrial scale LIB leachate and purified leachate to investigate the precipitation behavior of impurities, which include potentially toxic elements, such as F, Cl, and S. Regenerated precursors from the actual leachate, purified precursors, and a control sample are synthesized using the hydroxide co-precipitation method. Additionally, simulated precursors from simulated leachate are prepared in order to separate the effects of nonmetallic elements from the effects of metallic elements. The structure and electrochemical properties of the regenerated precursors and the corresponding cathode materials are examined. We first detect the presence of a significant amount of nonmetal elements, such as F as well as well-known metal elements, which include Al, Cu, and Fe, in the regenerated NMC. The concept of yield of precipitation (YOP) is introduced to assess the precipitation behavior of each element during the co-precipitation of the precursors. According to the concentration and YOP in the leachate and the precursors, six metal and three nonmetal elements are categorized. This categorization of impurity elements will certainly provide the LIB recycling industry with a valuable quality control guide.

Keywords: Impurity; Lithium-ion battery; Precipitation; Recycling; Regeneration.