Scalable Direct Recycling of NMC532 From End-of-Life Batteries via Physical Separation and Solid-State Relithiation

Direct recycling retains the structure and value of lithium-ion battery cathodes, however, most demonstrations rely on manually disassembled cells or chemical purification. A fully integrated, purification-free direct recycling process for high-Ni NMC cathodes is reported. Commercial NMC532/graphite pouch cells were sequentially shredded, wet-sieved, and subjected to electrostatic and magnetic separation to isolate cathode-rich fractions. Thermal debinding at 500°C removed polyvinylidene fluoride binder, enabling recovery of ≈90 wt% cathode active material (CAM) from aluminium current collectors with simple sieving. The optimal 1–4 mm fraction exhibited >98 wt% purity with <1 wt% total metallic contamination (Al, Cu, Fe). Synchrotron X-ray fluorescence/μ-X-ray absorption near edge structure mapping confirmed residual Cu and Fe as discrete oxide particles, physically isolated from NMC grains. Solid-state relithiation at 800°C in O₂, using either commercial or recycled Li₂CO₃, restored stoichiometry to Li₁Ni_0.5Mn_0.3Co_0.2O₂ while preserving spherical secondary particle morphology, providing specific capacities comparable to pristine NMC532 with stable cycling. A cradle-to-gate life cycle assessment quantified a product carbon footprint of 2.25 kg CO₂-eq kg⁻¹ for regenerated NMC using recycled Li₂CO₃, ≈15% lower than regenerated NMC with virgin Li₂CO₃. This study demonstrates a scalable, low-carbon direct recycling pathway that eliminates chemical purification, maintains high material performance, and is compatible with industrial waste streams.