Recovery of Valuable Metals from Spent Lithium Ion Batteries (LIBs) Using Physical Pretreatment and a Hydrometallurgy Process

Abstract

Lithium ion batteries are the most commonly used batteries at present, and because of the large number of people using and manufacturing them, the serious environmental problems caused by the final disposal of waste lithium batteries are worth discussing. In this study, lithium ion batteries were crushed with a crusher, and the obtained powder was then sieved and collected. The valuable metals in the lithium ion batteries were recovered using a hydrometallurgy process. The research included the use of acid leaching and chemical precipitation. Acid leaching of the cathode electrode powder with three kinds of acids, including citric acid, sulfuric acid, and hydrochloric acid, resulted in a leaching solution rich in lithium, cobalt, nickel, and manganese. The leaching solution obtained from hydrochloric acid leaching was selected as the liquid to be used for the precipitation experiments. Precipitation was performed first using a selective chemical precipitation method, and manganese was first precipitated as a black powder. The color of the leaching solution after manganese precipitation changed to dark pink, and the liquid was full of cobalt and nickel. Then, the cobalt and nickel were co-precipitated with ammonium citric, and the obtained precipitates were either pale pink or grayish pink. After precipitation of cobalt and nickel, only lithium was left in the transparent, colorless leaching liquid. Finally, lithium was concentrated through reduced pressure evaporation, and a green lithium salt was obtained.