Rapid electrothermal rejuvenation of spent lithium cobalt oxide cathode

Abstract

Increasing use of lithium-ion batteries has triggered intensive attention to the management of end-of-life batteries. Sustainable recycling of high-value cathode materials is needed to address resource depletion and environmental challenges. Traditional battery recycling methods, including pyro- and hydro-metallurgical methods, are material-destructive processes with substantial time, energy, and chemical consumption. Here, we develop a rapid and effective electrothermal method to rejuvenate spent lithium cobalt oxide cathodes within 30 s. By incorporating Mg and Al for surface engineering during the process, the structural stability of the regenerated cathode is enhanced by mitigating detrimental phase transformations at high voltage. Thus, the upcycled cathode exhibits a high capacity of ∼203 mA h g⁻¹ at 0.2C at an elevated cut-off voltage of 4.6 V, and maintains 84% of the initial capacity after 200 cycles. According to life cycle assessment and techno-economic analysis, our process exhibits significantly reduced environmental impacts with lower energy consumption, greenhouse gas emission, capital, and operating cost, and no solvent usage, making it a promising route to further upcycle other battery materials towards a circular economy.