M. Shi, D.E. Molina Montes de Oca, L.A. Diaz, J.R. Klaehn, A.D. Wilson, T.E. Lister
Idaho National Laboratory,
Keywords: critical materials, lithium-ion battery, recycling, lithium, cobalt, nickel
Summary:To strengthen the domestic critical materials supply chain for battery materials, end-of-life lithium-ion batteries (LIBs) are promising sources of lithium (Li), cobalt (Co), nickel (Ni) and graphite. Aiming to recover critical materials from spent LIBs, we have developed a series of operations to extract individual metals from the shredded LIB based on their electrochemical (EC) and chemical properties. The EC-Leach process can dissolve metals from the waste batteries to produce a metal-rich Cu-free leachate solution while isolating graphite and metallic copper. This leachate contains around 99% of critical metals in the shredded LIB materials, as well as impurity metals such as Al and Fe. To purify the leachate solution, a precipitation step has been developed to effectively remove the impurities and convert them into value-added side products. The purified leachate is then processed through separation stages. Based on customer needs and the properties of the feedstock, a series of customized procedures such as precipitation, solvent extraction or ion-exchange are applied to separate Co and Ni individually. To recover Li from the remaining Li-rich leachate, an electrodialysis process has also been developed. A CO2-capture agent has been incorporated to effectively isolate lithium carbonate. This method has also been applied to the Li recovery from natural brines. In total, these activities have produced high purity NiSO4, CoSO4, and Li2CO3. Through these methods, we have developed and demonstrated options which can be coupled with traditional methods used in mining to recover critical materials from LIBs.