标题：LiNi0.5Mn1.5O4synthesized through ammonia-mediated carbonate precipitation
作者：Gu, Yi-Jie ;Li, Yu ;Fu, Yang ;Zang, Qing-Feng ;Liu, Hong-Quan ;Ding, Jian-Xu ;Wang, Yan-Ming ;Wang, Hai-Feng ;Ni, Jiangfeng
作者机构：[Gu, Yi-Jie ;Li, Yu ;Fu, Yang ;Zang, Qing-Feng ;Liu, Hong-Quan ;Ding, Jian-Xu ;Wang, Yan-Ming ] College of Materials Science and Engineering, Shandong 更多
摘要：Abstract We synthesized LiNi0.5Mn1.5O4cathode materials by using ammonia-mediated carbonate precipitation, and we studied how the ammonia concentration during synthesis (0.1-0.5 mol/L) affected the structural, physicochemical, and electrochemical characteristics of the prepared materials. X-ray diffraction and Rietveld refinement reveal that the amount of Li/Ni antisite defects in the LiNi0.5Mn1.5O4depend much on the ammonia concentration. The LiNi0.5Mn1.5O4prepared at 0.3 mol/L has the fewest Li/Ni antisite defects. This sample also delivers the best electrochemical performance, retaining a capacity of 133.5 mAh g-1after 20 cycles at 0.1 C. Electrochemical impedance spectroscopy confirms that the LiNi0.5Mn1.5O4prepared at 0.3 mol/L has lower charge transfer resistance, correlating with its better ion diffusion kinetics than the other materials.
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