From Spent Graphite to Battery‐Grade Anode Material Through High‐Temperature Regeneration

Abstract

The recovery of graphite from end‐of‐life lithium‐ion batteries is essential for establishing circular battery value chains, yet graphite contained in industrial black mass streams remains largely underutilized due to contamination and structural degradation. This study demonstrates the direct regeneration of high‐performance graphite from realistic recycling feedstocks without dedicated purification steps. High‐temperature treatment under an inert atmosphere (2000–3000 °C) increases graphite purity from 92.0% to 99.9%, while simultaneously inducing defect healing and restoring graphitic order. Raman spectroscopy, X‐ray diffraction, specific surface area, and chemical analysis reveal that impurity removal and structural reconstruction are temperature‐dependent processes that emerge only above 2000 °C. In contrast, lower treatment temperatures (≤1500 °C) result in neither effective purification nor significant structural recovery. A treatment temperature of 2700 °C provides an effective balance between material quality and energy demand. The regenerated graphites deliver reversible capacities of up to 350 mAh g−1 and initial Coulombic efficiencies of 94.0%, while an additional amorphous carbon coating further enhances rate performance. These results establish a mechanistic link between impurity removal, graphitic reconstruction, and electrochemical behavior, demonstrating a practical route for converting highly contaminated graphite waste into high‐performance anode materials and opening a pathway toward industrial‐scale graphite circularity.