Exploring Optimal Li-ion Substitution for High Na-content P2-Na0.67+a[LixNi0.33−yMn0.67−z]O2 Cathodes for Sodium-ion Batteries. Issue 3 (1st March 2023)

• Record Type: Journal Article
• Authors: Ghosh, Arindam; Senthilkumar, Baskar; Ghosh, Subham; Amonpattaratkit, Penphitcha; Senguttuvan, Premkumar
• Is Part Of: Journal of the Electrochemical Society. Volume 170:Issue 3(2023)
• Publication Date: 2023-03-01
• Subjects: Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/acc27a
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : P2-type Na0.67 [Ni0.33 Mn0.67 ]O2 layered oxide cathode is attractive for practical Na-ion battery application due to its high voltage Ni 4+ /Ni 2+ redox and good air-stability. However, it suffers from rapid capacity decay originating from high voltage P2-O2 transformation. To alleviate this issue, herein we explore optimum Li-substitution into the transition metal layer of Na0.67 [Ni0.33 Mn0.67 ]O2 to tailor a series of high Na-content P2-type cathodes. Among them, Na0.85 [Li0.14 Ni0.29 Mn0.57 ]O2 cathode with optimal Li-substitution exhibits reversible capacities of ∼168 mAh g −1 at 0.1C rate and good cycling stability (82% of retention after 100 cycles at 1C rate). In-situ XRD measurement reveals the formation of complete solid-solution and X-ray absorption spectroscopy studies confirm the participation of Ni 4+ /Ni 2+ and Mn 4+ /Mn 3+ redox couples during Na (de)intercalation of the Na0.85 [Li0.14 Ni0.29 Mn0.57 ]O2 . A full Na-ion cell (Na0.85 [Li0.14 Ni0.29 Mn0.57 ]O2 ||hard carbon) is demonstrated with an energy density of 420 Wh kg −1 .