Fabrication of Lithium Hydroxide(LiOH) from Spent Cathodic Material(LiNixCoyMnzO2) by Hydrogen Reduction

Tae  Yi Kang; Seong  bong Heo; Jei-Pil  Wang

Tae Yi Kang Department of Metallurgical Engineering, College of Engineering, Pukyong National University, Busan 48547, Republic of Korea.
Seong bong Heo Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul, 04763, Republic of Korea.
Jei-Pil Wang Department of Metallurgical Engineering, College of Engineering, Pukyong National University, Busan 48547, Republic of Korea.

Abstract

In this study, hydrogen reduction and water leaching process were conducted to recover lithium from NCM-based cathode active material(LiNixCoyMnzO2). The various effects of hydrogen concentratin, flow rate, temperature, and reaction time were investigated to obtain higher recover rate and purity. Based on the decomposition and stoichiometric analysis, the optimal conditions for hydrogen reduction were determined, showing a weight reduction of 23.81%. Since Li2O is water-soluble, it was separated into solution through water leaching and filtration. After crystallization, a re-dissolution process was carried out to remove impurities, and drying conditions were established to recover lithium hydroxide monohydrate. The results from the optimal condition tests showed a recovery rate of lithium with 92.77% and a purity of lithium hydroxide monohydrate with 99.8%.