Abstract
Direct regeneration offers a shortcut to close the material supply loop of lithium-ion batteries and is a promising recycling strategy. However, in spent LiNi0.5Co0.2Mn0.3O2 positive electrode, severe bulk cation disorder and surface rock salt phase hinder Li+ reinsertion. Moreover, the coexistence of single and poly-crystal particles in commercial batteries further complicates uniform re-lithiation and morphological regeneration. Herein, we propose an oxidation strategy to simultaneously regulate the structural reconstruction and morphological evolution of spent material. During oxidation, surface NiO transforms into NiOOH, while targeted oxidation of the anti-site Ni2+ to Ni3+ in the bulk reduces Li+/Ni2+ mixing. This reconstructs Li+ diffusion channels from surface to bulk, facilitating re-lithiation. Meanwhile, structural changes induce lattice expansion in secondary particles, causing their decomposition into primary particles and forming uniform precursor particles. These particles, with continuous Li+ transport channels and NiOOH surface, agglomerate into large single-crystal during calcination. The regenerated LiNi0.5Co0.2Mn0.3O2 achieves a high tap density of 2.57 g/cm3 and retains 80.2% capacity after 600 cycles. This work presents a concept for the direct regeneration of degradable positive materials.
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Acknowledgements
This work was supported by the National Key Research and Development Program of China (2025YFF0516300 [L.Y.]), the National Natural Science Foundation of China (NSFC, Grant Nos. 22479058 [L.Y.], 12205325 [W.L.]) and the Key R&D Program of Hubei Province (2024BCB091 [L.Y.]). We thank the staff members of the Multi-Physics Instrument Neutron Scattering (https://cstr.cn/31113. 02. CSNS. MPI) at the China Spallation Neutron Source (CSNS) (https://cstr.cn/31113. 02. CSNS), for providing technical support and assistance in data collection and analysis.
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S. H. conducted the experiments and prepared the manuscript. Y.Z., S.L., Z.T., W.L., Y.X., and W.Y. contributed to the completion of part of the characterizations. Y.L. (Yaqi Liao), H.J., Y. K., Y.S., and Y.L. (Yuelin Lv) gave instructive advice to perform the experiments. L.Q., Y.H. and L.Y. conceived and designed the research. All authors contributed to the discussion of the manuscript.
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Hao, S., Zhang, Y., Liu, S. et al. Oxidation-reconstructed Li+ transport enables high-tap-density single-crystal regeneration of spent LiNi0.5Co0.2Mn0.3O2 positive electrodes. Nat Commun (2026). https://doi.org/10.1038/s41467-026-71730-3
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DOI: https://doi.org/10.1038/s41467-026-71730-3
