Cycling Performance and Structure Evolution of Co-free Lithium- and Manganese-Rich Layered Oxides in Lithium-Ion Batteries

Journal Article · Mon Nov 30 19:00:00 EST 2026 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1945-7111/ae2890· OSTI ID:3013474

Badami, Pavan ^[1]; Kwok, C. Y. ^[2]; Gargye, Avi ^[1]; Trask, Stephen ^[3]; Dogan, Fulya ^[1]; Lopez, Antonio ^[4]; Croy, Jason ^[1]; Balasubramanian, Mali ^[2]; Abraham, Daniel P ^[1]

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1. Argonne National Laboratory (ANL)
2. ORNL
3. Argonne National Laboratory
4. Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY

Lithium- and manganese-rich (LMR) layered oxides are high-capacity cathode materials that are being considered for electric vehicle (EV) lithium-ion batteries (LIBs). Here, we investigate the electrochemical cycling behavior of cells containing a cobalt-free LMR oxide, 0.3Li2MnO3·0.7LiMn0.5Ni0.5O2, paired with either Li or graphite anodes. Two- and three-electrode cells are cycled under varying conditions to examine the effects of oxide activation, upper cutoff voltage, separator type, and electrolyte composition. Post-cycling characterization of harvested electrodes, with electrochemical, X-ray absorption spectroscopy, and solid-state 6Li nuclear magnetic resonance spectroscopy techniques, are used to correlate cell performance changes with redox state evolution in the oxide and Li inventory shifts in the cell. Our results show that capacity fade and impedance rise primarily originate at the graphite anode and LMR cathode, respectively. Notably, while Ni undergoes reversible redox, Mn shows no evidence of bulk redox activity even in highly-aged electrodes: only relithiated LMR electrodes show some reduction of Mn. Graphite electrodes degrade due to particle isolation and SEI growth, exacerbated by Mn dissolution and deposition on graphite anodes. These findings highlight the coupled structural and electrochemical degradation mechanisms in LMR/graphite cells and underscore lithium inventory retention and electrode interfacial stability as critical factors for enhancing long-term performance.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 3013474
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 12 Vol. 172
• Country of Publication: United States
• Language: English