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Abstract: Li2CO3‐passivated Li3N with high stability is prepared by aging Li3N powder in dry air, and is then used as an electrode additive for a Li(Li0.18Ni0.15Co0.15Mn0.52)O2 (LLMO) cathode material. The material shows a large irreversible capacity of 800 mA h g−1 during the first charge, with the formation of a Li2N intermediate product. Acting as a Li+ sacrificial salt for a LLMO(+)/graphite(−) Li‐ion battery, 2 wt % Li3N results in a 10 % increase in discharge capacity. The Li2N intermediate product reacts with the electrolyte, forming a uniform and regular surface film on the cathode. Moreover, chemical bonding between LLMO and N improves the electrode stability, resulting in excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Li-rich layered oxide Li1.18Ni0.15Co0.15Mn0.52O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium-ion battery and its Na+ storage properties are comprehensively studied in terms of galvanostatic charge-discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium-ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g−1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g−1 for 200 cycles at 5 C rate. Moreover, ex situ ICP-OES suggests interesting mixed-ions migration processes: In the initial two cycles, only Li+ can intercalate into the LNCM cathode, whereas both Li+ and Na+ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge-discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium-ion batteries. [ABSTRACT FROM AUTHOR]