Synthesis of High-Quality NMC111 and Ni-Rich NMC622 from End-of-Life Li-NMC Batteries

In recent years, lithium-ion batteries (LIBs) have dominated the energy storage field, resulting in a growing volume of end-of-life LIBs. Here, we propose an approach to regenerate the Li-NMC cathode active material utilizing an end-of-life Li-ion battery (Li-NMC). In particular, we used the degraded cathode material from an end-of-life NMC battery as a precursor for the required transition metals. Furthermore, we tuned the elemental stoichiometry to prepare different variants of NMC cathode active materials. Using this approach, we successfully synthesized both NMC111 and Ni-rich NMC622 with high phase purity. Elemental, morphological, and structural analyses confirmed that the regenerated materials were free from cation mixing and exhibited structural quality comparable to that of commercial-grade NMC cathode active materials. This work demonstrates a cost-effective direct regeneration process for spent NMC, compared with pyrometallurgy and hydrometallurgy, in which critical metals are recycled as alloys and individual salts, respectively. Furthermore, this study reveals that the regeneration of end-of-life NMC batteries can yield high-quality NMC cathode active materials, offering a sustainable approach to managing battery waste and maximizing the value of critical metals.