Spatial Redistribution of Intrinsic Cation Disorder Toward Ultra‐Stable Regeneration of LiNi _0.5 Co _0.2 Mn _0.3

ABSTRACT

Conventional direct regeneration of spent LiNi _0.5 Co _0.2 Mn _0.3 O ₂ cathode material typically aims to eliminate structural defects, such as disordered cation mixing in the bulk phase and electrochemically inert rock‐salt phase formed on the surface. Such regeneration processes feature simple procedures, enabling efficient reconstruction of crystal ordering and effective capacity restoration. However, perfectly ordered layered structures are inherently unstable during long‐term charge–discharge cycling. Here, we propose a defect‐empowered regeneration strategy that rationally modulates and harnesses Li/Ni cation disorder instead of completely eradicating such defects. The electrochemically inert rock–salt phase was dismantled, while intermittent nickel was intentionally retained within lithium slabs. Regeneration was completed within 30 min, outpacing conventional approaches by orders of magnitude. The regenerated material delivered an initial discharge capacity of 164.39 mAh g ⁻¹ at 0.2C. It exhibited near 100% capacity retention after 100 cycles at 0.5C and 200 cycles at 1C, demonstrating significantly enhanced stability. Our findings reframe cation disorder as an effective lattice stabilizer, offering a rapid and sustainable pathway for battery recycling.