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DOE OSTI · 3409112

Upcycling Polycrystalline LiNi1/3Mn1/3Co1/3O2 to High-Performance Large-Grained LiNi0.6Mn0.2Co0.2O2 via Simplified Polyol-Mediated Recycling

Yu, Lu [Oak Ridge National Laboratory]·Bai, Yaocai [Oak Ridge National Laboratory]·Fink, Kae [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000193634632)·Mangum, John [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000259267565)·Liu, Jue [Oak Ridge National Laboratory]·Belharouak, Ilias [Oak Ridge National Laboratory]
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Abstract

The escalating demand for lithium-ion batteries (LIBs) necessitates advanced recycling strategies that can address both resource scarcity and environmental impact. While conventional hydrometallurgy shows promise, it is challenged by complexity, impurity management, and environmental footprint. Here, we report a strategic polyol-metallurgy recycling process that efficiently transforms spent polycrystalline LiNi1/3Mn1/3Co1/3O2 (NMC111) into high-performance large-grained LiNi0.6Mn0.2Co0.2O2 (NMC622), offering dual benefits of compositional upcycling and morphology upgradation. Our approach leverages a polyol system with meticulous control over nickel salt addition and the precipitation process. This yields upcycled cathode materials possessing excellent structural integrity, well-defined large-grained particles (5-10?..mu..m), and robust electrochemical performance, including a specific capacity of ~182 mAh g-1 at C/10 and 88.0% capacity retention after 100 cycles. This facile and multifunctional process provides an environmental-friendly pathway for advanced cathode recycling, significantly contributing to a circular economy for LIBs through precise control over critical material attributes.

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25 ENERGY STORAGE36 MATERIALS SCIENCEbattery recyclingcathode upcyclingcritical materials recoverylithium-ion batteriessingle-crystal cathode

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Yu, Lu [Oak Ridge National Laboratory], Bai, Yaocai [Oak Ridge National Laboratory], Fink, Kae [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000193634632), Mangum, John [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000259267565), Liu, Jue [Oak Ridge National Laboratory], Belharouak, Ilias [Oak Ridge National Laboratory]. 2026-07-17. Upcycling Polycrystalline LiNi1/3Mn1/3Co1/3O2 to High-Performance Large-Grained LiNi0.6Mn0.2Co0.2O2 via Simplified Polyol-Mediated Recycling. https://doi.org/10.1016/j.jpowsour.2026.240946

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