Dual Roles of Li 3 N as an Electrode Additive for Li‐Excess Layered Cathode Materials: A Li‐Ion Sacrificial Salt and Electrode‐Stabilizing Agent

• Published in: Chemistry : a European journal Vol. 24; no. 52; pp. 13815 - 13820
• Main Authors: Bian, Xiaofei, Pang, Qiang, Wei, Yingjing, Zhang, Dong, Gao, Yu, Chen, Gang
• Format: Journal Article
• Language: English
• Published: 18.09.2018
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201801809

Abstract Li 2 CO 3 ‐passivated Li 3 N with high stability is prepared by aging Li 3 N powder in dry air, and is then used as an electrode additive for a Li(Li 0.18 Ni 0.15 Co 0.15 Mn 0.52 )O 2 (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 Li 2 N intermediate product. Acting as a Li + sacrificial salt for a LLMO(+)/graphite(−) Li‐ion battery, 2 wt % Li 3 N results in a 10 % increase in discharge capacity. The Li 2 N 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.