Comparative Study for Selective Lithium Recovery via Chemical Transformations during Incineration and Dynamic Pyrolysis of EV Li-Ion Batteries

Abstract

Selective leaching of Li from spent LIBs thermally pretreated by pyrolysis and incineration between 400 and 700 °C for 30, 60, and 90 min followed by water leaching at high temperature and high L/S ratio was examined. During the thermal pretreatment Li2CO3 and LiF were leached. Along with Li salts, AlF3 was also found to be leached with an efficiency not higher than 3.5%. The time of thermal pretreatment did not have a significant effect on Li leaching efficiency. The leaching efficiency of Li was higher with a higher L/S ratio. At a higher leaching temperature (80 °C), the leaching of Li was higher due to an increase in the solubility of present Li salts. The highest Li leaching efficiency of nearly 60% was observed from the sample pyrolyzed at 700 °C for 60 min under the leaching condition L/S ratio of 20:1 mL g−1 at 80 °C for 3 h. Furthermore, the use of an excess of 10% of carbon in a form of graphite during the thermal treatment did not improve the leaching efficiency of Li.

Lithium-Ion Battery Recycling─Influence of Recycling Processes on Component Liberation and Flotation Separation Efficiency

“…Yang et al concluded that Ni ions from NMC were reduced to metallic Ni, while the Co 3+ and Mn 3+ ions appeared to maintain their trivalent form. Various studies explained that thermal pretreatment can promote the carbothermic reduction of the LMOs and has the advantage of improving their leaching efficiency and decreasing the amount of reducing agents (e.g., H 2 O 2 ) needed during hydrometallurgical treatment. − …”

Assessment of recycling methods and processes for lithium-ion batteries

“…During thermal pre-treatment of LIBs, Li 2 CO 3 is commonly formed by the following mechanism. During the combustion of graphite and organic compounds in the incineration process, high temperatures and the presence of oxygen result in the formation of CO 2 and CO. LiCoO 2 is reduced by carbon and carbon monoxide to Co 3 O 4 , Li 2 CO 3 , and CO 2 as illustrated by Equation 2 ( Balachandran et al., 2021 ). …”

“…In this procedure, lithium is first recovered then the other metals remain in the filter residue because lithium salts show good solubility in water. During thermal treatment, carbon reduces the metal oxides to lower valence states which improves the leaching process ( Balachandran et al., 2021 ). Water leaching reduces the need for additional reagents which minimizes the generation of secondary pollution.…”

Roadmap for a sustainable circular economy in lithium-ion and future battery technologies

“…Another approach under current research is the early-stage lithium recovery [160,167]. Thermal treatment conditions like temperature, holding time and atmosphere are investigated to produce water soluble lithium compounds [160,167,177]. Afterwards the mechanically separated black mass can be water leached to recover lithium salts like lithium carbonate, without chemical consumption [160,167,177].…”

“…Thermal treatment conditions like temperature, holding time and atmosphere are investigated to produce water soluble lithium compounds [160,167,177]. Afterwards the mechanically separated black mass can be water leached to recover lithium salts like lithium carbonate, without chemical consumption [160,167,177]. Additional (supercritical) CO 2 treatment to optimize lithium yields during leaching is also possible [160,167].…”