A High-Capacity O2-Type Li-Rich Cathode Material with a Single-Layer Li2MnO3 Superstructure

作者:Zuo, Yuxuan; Li, Biao; Jiang, Ning; Chu, Wangsheng; Zhang, Hao; Zou, Ruqiang; Xia, Dingguo*
来源:Advanced Materials, 2018, 30(16): 1707255.
DOI:10.1002/adma.201707255

摘要

A high capacity cathode is the key to the realization of high-energy-density lithium-ion batteries. The anionic oxygen redox induced by activation of the Li2MnO3 domain has previously afforded an O3-type layered Li-rich material used as the cathode for lithium-ion batteries with a notably high capacity of 250-300 mAh g(-1). However, its practical application in lithium-ion batteries has been limited due to electrodes made from this material suffering severe voltage fading and capacity decay during cycling. Here, it is shown that an O2-type Li-rich material with a single-layer Li2MnO3 superstructure can deliver an extraordinary reversible capacity of 400 mAh g(-1) (energy density: approximate to 1360 Wh kg(-1)). The activation of a single-layer Li2MnO3 enables stable anionic oxygen redox reactions and leads to a highly reversible charge-discharge cycle. Understanding the high performance will further the development of high-capacity cathode materials that utilize anionic oxygen redox processes.