College of Materials and Chemical Engineering, Hubei Provincial Collaborative Innovation Center for New Energy Microgrid , China Three Gorges University , 8 Daxue Road , Yichang , Hubei 443002 , China.
Department of Physics , Sam Houston State University , Huntsville , Texas 77341 , United States.
ACS Appl Mater Interfaces. 2018 Apr 11;10(14):11663-11670. doi: 10.1021/acsami.7b19692. Epub 2018 Mar 29.
Layered LiNiCoMnO (NCM333) is successfully coated by fast ionic conductor LiTi(PO) (LTP) via a wet chemical method. The effects of LTP on the physicochemical properties and electrochemical performance are studied. The results reveal that a highly layered structure of NCM333 can be well maintained with less cation mixing after LTP coating. LTP of about 5 nm thickness is coated on the surface of NCM333. Such an LTP coating layer can effectively suppress the side reactions between NCM333 and electrolyte but will not hinder the lithium ion transmission. As a result, LTP-coated NCM333 owns an improved capability and cyclic performance, for example, NCM333/LTP delivers an initial capacity as high as 121.0 mA h g with a capacity retention ratio of 82.3% after 200 cycles at 10 C, whereas NCM333 only has an initial capacity of 120.4 mA h g with a very low capacity retention ratio of 66.4%. This method of using a fast ionic conductor like LTP as a coating material may provide a simple and effective strategy to modify those electrode materials with poor cyclic performance.
层状 LiNiCoMnO（NCM333）通过湿化学方法成功地被快离子导体 LiTi(PO)（LTP）包覆。研究了 LTP 对其物理化学性质和电化学性能的影响。结果表明，LTP 包覆后，NCM333 的高度层状结构可以得到很好的保持，阳离子混合较少。NCM333 表面包覆了约 5nm 厚的 LTP。这种 LTP 包覆层可以有效地抑制 NCM333 与电解质之间的副反应，但不会阻碍锂离子的传输。因此，LTP 包覆的 NCM333 具有改进的能力和循环性能，例如，NCM333/LTP 在 10C 下循环 200 次后，初始容量高达 121.0mAh g，容量保持率为 82.3%，而 NCM333 的初始容量仅为 120.4mAh g，容量保持率非常低，为 66.4%。这种使用快离子导体如 LTP 作为包覆材料的方法可能为改善那些循环性能差的电极材料提供了一种简单而有效的策略。
