Improvement of long-term cycling performance of Li[Ni0.8Co0.15Al0.05]O2 by AlF3 coating
Improvement of long-term cycling performance of Li[Ni0.8Co0.15Al0.05]O2 by AlF3 coating
复制标题
DOI：
10.1016/j.jpowsour.2013.01.045
复制
发表时间：
2013-07-15
影响因子：
9.2
通讯作者：
Sun, Yang-Kook
中科院分区：
文献类型：
--
作者：
Lee, Sang-Hyuk;Yoon, Chong Seung;Sun, Yang-Kook
采用简单的干涂工艺在Li[Ni0.8Co0.15Al0.05]O-2正极材料表面涂覆50 nm厚的AlF3层。虽然原始和alf3涂层的Li [Ni0.8Co0.15Al0.05]O-2的初始放电容量几乎相同，但alf3涂层显著提高了[Ni0.8Co0.15Al0.05]O-2在全电池结构（石墨阳极）下的电化学性能，特别是在高温（55℃）下。此外，alf3包覆的[Ni0.8Co0.15Al0.05]O-2具有较好的热稳定性。电化学性能的提高可能是由于AlF3涂层延缓了过渡金属在HF攻击下的溶解。电化学阻抗谱和透射电镜直接证明AlF3涂层抑制了循环过程中电荷转移电阻的增加和正极材料的粉碎。Elsevier B.V.出版
The surface of a Li[Ni0.8Co0.15Al0.05]O-2 cathode material was coated by a 50-nm thick AlF3 layer using a simple dry coating process. Although the initial discharge capacity of pristine and AlF3-coated Li [Ni0.8Co0.15Al0.05]O-2 was nearly same, the AlF3-coating significantly improved the electrochemical performances of [Ni0.8Co0.15Al0.05]O-2 in a full cell configuration (graphite anode), especially at an elevated temperature (55 degrees C). Furthermore, the AlF3-coated [Ni0.8Co0.15Al0.05]O-2 had better thermal stability than the pristine electrode. The improved electrochemical performance likely arose from the AlF3 coating layer which may have retarded the transition metal dissolution from HF attack. Electrochemical impedance spectroscopy and transmission electron microscopy provided direct evidence that the AlF3 coating layer suppressed the increase in charge transfer resistance and cathode material pulverization during cycling. Published by Elsevier B.V.