Lithium Process Chemistry
Spent lithium-ion (Li-ion) batteries are considered to be a secondary source of valuable metals, such as cobalt, nickel, aluminum, copper manganese, etc. Recently, the recovery of lithium has been considered to be needed not only to increase the material recovery rate of the existing process, but also to use the spent lithium-ion batteries (LiBs) as a source of the metal, of which almost one-third of the production is applied in the battery industry. In this chapter research activities and current recycling technologies for LiBs are described. The characterization of the waste shows that spent LiBs are heterogeneous waste not only because of the different materials used for battery construction, but also because of the differences in the active material composition. Discharging processes, followed by mechanical pretreatment and separation are necessary parts of the spent batteries treatment, especially when hydrometallurgy is implemented for metal recovery. This chapter describes current efforts in recycling using hydrometallurgical treatment applying inorganic and organic acids for leaching, as well as bioleaching methods. Processes of metal recovery using solvent extraction and precipitation are also described. Thermal pretreatments are introduced as an example for removing organic compounds and carbon in order to improve the metal recovery. Current industrial processes that apply mechanical treatment, pyrometallurgy, hydrometallurgy, or combined processes for LiBs recycling are described as well.