Graphite reuse from different spent lithium-ion batteries: Impact on the structure-performance relationship

The global transition to e-mobility is accelerating the demand for lithium-ion batteries (LIBs) and the critical raw materials needed for their production. Despite constituting a significant fraction of battery mass, graphite remains largely excluded from current recycling practices. This omission exacerbates supply risks related to graphite's energy-intensive production and geopolitical concentration. Here, we present a comparative study focusing on two different graphite recovery pathways: hydrometallurgical leaching (HML) and direct physical recycling (DPR), applied to commercial LIBs with NMC, LCO, and LFP chemistries. Structural and compositional analyses reveal that while materials recycling following both methods retain the graphitic phase, HML achieves lower impurity levels (Li, Cu, Al) than DPR. Electrochemical testing shows that high initial capacities (∼420 mA h g−1) for HML graphite (GE1) do not guarantee long-term cycling stability, as lithium trapping and structural defects drive capacity fade. Notably, DPR-recovered graphite from C-LFP cells, exhibiting the cleanest morphology and the highest structural order, maintains ∼280 mA h g−1 over 800 cycles. These results demonstrate that structural order, crystallite size, and chemical purity govern the electrochemical durability of recycled graphite. It is worth highlighting the feasibility of reusing graphite extracted from LIBs not dependently on the electrode chemistries and on the electrochemical histories.