Recycling of Li and Co from spent LiCoO2 cathode materials through a low-temperature urea-assisted sulfation roasting approach

Abstract

The lithium-ion battery industry is experiencing explosive growth. Efficiently and greenly recycling Li, Co and other valuable metals is extremely important to alleviate the scarcity of resources and protect the environment. In this study, an improved recycling strategy is proposed to convert spent LiCoO₂ batteries into water-soluble sulfate below 350 °C using the auxiliary effect of urea on sulfation roasting. This strategy not only allows for the direct synthesis of precursors for regeneration after selective recovery of lithium and cobalt but also further reduces the roasting temperature requirement compared to the conventional salt-thermal method. After roasting, Li and Co can be recovered from the solution by simple aqueous leaching. Under optimal conditions, the leaching rates of Li and Co were 94.94% and 95.47%, respectively. Subsequently, the Li and Co compounds that could be used as battery precursors were obtained by the addition of CO₃²⁻. Characterized by high efficiency, low energy consumption, absence of secondary pollution, and utilization of inexpensive and readily accessible raw materials, this approach offers a novel concept in the domain of lithium-ion battery recycling via salt-thermal methods.