Hydrometallurgical process of spent lithium-ion battery recycling Part. 1 Chemical leaching of valuable metals from cathode active materials: Review and case study

Abstract

The rapid growth in global demand for lithium-ion batteries (LIBs) has led to a corresponding increase in the number of spent LIBs. This situation highlights the importance of recycling these batteries to conserve the environment and preserve the raw materials used in their production. Among the various commercial recycling methods, leaching is widely used in hydrometallurgical flowsheets. Through acid leaching with sulfuric, hydrochloric, nitric, phosphoric, citric, and other organic acids such as oxalic, formic, and malic acids, along with alkaline agents such as ammonia, ammonium carbonate, ammonium sulfate, and sodium hydroxide, valuable metals such as Co, Ni, Mn, and Li are recovered. In the leaching process, factors such as leaching agent concentration, reductants, temperature, time, and solid-to-liquid (S/L) ratio impact leaching efficiency. These parameters are also interrelated, requiring an analysis of their interactions. It has been shown that leaching can dissolve over 90 % of metals, which are the primary components of cathodes. This paper presents a comprehensive review of the leaching parameters and optimal conditions for maximizing efficiency, focusing specifically on chemical leaching through an in-depth analysis of relevant literature, experimental details, and cost considerations in a case study.