Recovering Lithium from the Cathode Active Material in Lithium-Ion Batteries via Thermal Decomposition

Abstract

In this study, calcination tests were performed on a mixed sample of lithium cobalt oxide and activated carbon at 300–1000 C under an argon atmosphere. The tests were conducted to discover an effective method for recovering lithium and cobalt from the cathode active material used in lithium-ion batteries. Additionally, the effect of soluble fluorine on the purification of lithium carbonate was investigated by the addition of lithium fluoride to an aqueous lithium hydroxide solution and a CO2 flow test was performed. The lithium recovery was ≥90% when the calcination occurred at temperatures of 500–600 C. However, the percent recovery decreased at temperatures ≥700 C. It was demonstrated that in order to increase the recovery while maintaining 99% purity of lithium carbonate in the recovered material, it was imperative to increase the temperature of the solution and to limit the F/Li ratio (mass%/mass%) in the solution to a value that did not exceed 0.05.

Early-Stage Recovery of Lithium from Tailored Thermal Conditioned Black Mass Part I: Mobilizing Lithium via Supercritical CO2-Carbonation

“…In this study, it will be investigated by using SCO2. There are different studies in literature optimizing a reductive thermal treatment of black mass for mobilizing lithium via subsequent H2O-leaching [46,47,[69][70][71][72][73][74]. It should be recalled that in [46,47], which were already discussed in chapter 1.1.3, a combination of direct carbonation and indirect carbonation was performed: On one hand, a reductive thermal treatment with adding a carbon-reducing agent like lignite or carbon black contributes to the formation of Li2CO3, hence direct carbonation.…”

“…However, in all reported studies [46,47,[69][70][71][72][73][74], first, the battery cells are shredded, and, after extracting, a black mass is thermally treated. Battery systems used are LCOcathode based [69,72,74], LMO-cathode based [71,74], or NMC-cathode based [73,74]. In [73], the only cathode material is used.…”

“…In [73], the only cathode material is used. Most studies focus on a thermal treatment in an inert atmosphere, like a vacuum, Ar or N2 [69,71,72,74,75] or in the air [70] instead of CO2. CO2 was only used in [73].…”

“…CO2 was only used in [73]. The performed reductive roasting reportedly also contributes to the carbonation of lithium by precipitating it from the black mass matrix [19,70,72,74,76].…”

Recovery of Platinum Group Metals from Spent Automotive Catalysts Using Lithium Salts and Hydrochloric Acid

“…In order to recover metals from LIBs, we applied a carbon reduction method, which utilizes carbon powder as a reducing agent. Through this dry process, we succeeded in separating and recovering Li and Co from an LIB cathode model (LiCoO 2 ) [24]. When targeting waste LIBs, heating is an appropriate, inexpensive treatment; however, in such situations, it is necessary to control the levels of F originating from the electrolytes (e.g., lithium hexafluorophosphate, LiPF 6 ) and the binders (e.g., polyvinylidene difluoride, PVDF) of these batteries.…”