Direct electrochemical lithium recovery from acidic lithium-ion battery leachate using intercalation electrodes

Abstract

With the development of the electric vehicle industry, the demand for the lithium-ion battery (LIB) has considerably grown, and thus the recycling of LIB has become an important issue. Until now, only solvent extraction, leaching, and precipitation methods have been applied for lithium recovery from LIB leachate, but these methods need a series of separation of coexisting ions, and lithium is recovered in the final step of the recycling process. The electrochemical method is one of the promising methods for lithium recovery with several advantages such as high lithium selectivity, short reaction time, and low energy consumption. In this study, lithium is successfully recovered from actual industrial scale LIB leachate by electrochemical sorption using lithium manganese oxide (LMO) and activated carbon (AC) electrodes. The effects of current and electrochemical reaction time on lithium recovery from the LIB leachate are investigated and it is found that the lithium recovery capacity, purity, and the selectivity increase with higher current and longer reaction time. The maximum lithium recovery capacity of 3.51 mmol g −1 and energy consumption of 3.77 Wh mol −1 (13.6 kJ mol −1) is obtained during the electrochemical lithium recovery from the LIB leachate. The reusability of LMO/AC system is also tested and confirms that the lithium recovery capacity is maintained without the apparent degradation of the electrodes. This direct electrochemical lithium recovery from the LIB leachate could be more efficient than the established hydrometallurgical lithium recovery comprised of multiple separation steps of impurity elements.