New insight into Li/Ni disorder in layered cathode materials for lithium ion batteries: a joint study of neutron diffraction, electrochemical kinetic analysis and first-principles calculations

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2017, Vol.5 (4), p.1679-1686
• Main Authors: Zhao, Enyue, Fang, Lincan, Chen, Minmin, Chen, Dongfeng, Huang, Qingzhen, Hu, Zhongbo, Yan, Qing-bo, Wu, Meimei, Xiao, Xiaoling
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/C6TA08448F

Although layered cathode materials LiNi x Mn y Co 1−x−y O 2 have attracted much attention due to their number of advantages, the issue of Li/Ni disorder seriously restricts their electrochemical properties. It is very important and pivotal for the better optimization of layered cathode materials to clearly explain the detailed relationships among the Li/Ni disorder, Li + migration resistance, electrochemical kinetics and electrochemical properties. Here we focus on the LiNi x Mn y Co 1−x−y O 2 cathode material and report relationships among the crystal structures, Li + migration resistance, electrochemical kinetics and electrochemical properties by combining neutron diffraction techniques, electrochemical kinetic analysis techniques and first-principles calculation methods. The results suggest that more Li + /Ni 2+ ion exchange will shrink the inter-slab space thickness, causing a higher Li + ion migration barrier and inferior electrochemical kinetics, all of which should be responsible for the limited electrochemical properties.