Document Type
Article
Publication Date
1-25-2018
Abstract
The present work systematically probes and tracks the phase transition of Li-rich layered Li[Li0.2Mn0.54Ni0.13Co0.13]O2 (marked as LMNCO) by using an ex-situ chemical activation that is realized through ion-exchange and post-annealing processes, in order to understand related electrochemical performances of Li-rich cathode materials for advanced lithium-ion batteries. Ion exchanges of H+-Li+ and subsequent TBA+-H+ (TBA: tetrabutylammonium) in LMNCO are carried out, resulting in its layered-to-spinel phase transition after optimal heat treatments. The resultant compound shows a Li4Mn5O12-type spinel structure. This converted spinel cathode material can deliver discharge capacities higher than 300 mAh/g at 0.1 C and 200 mAh/g at 1 C (1 C = 250 mA/g), respectively, and also exhibits better cycling stability and rate capability in comparison with pristine layered LMNCO and other derivatives. This work offers a feasible route to study all changes of morphologies, crystal structures, chemical compositions, surface areas and related electrochemical lithium storage behaviors during phase transitions of Li-rich layered cathode materials, and thus provides insights on optimizing electrochemical performances for high-energy and high-power lithium ion batteries.
Publication Source (Journal or Book title)
Journal of Alloys and Compounds
First Page
385
Last Page
395
Recommended Citation
Zhao, J., Kuai, X., Dong, X., Wang, H., Zhao, W., Gao, L., Wang, Y., & Huang, R. (2018). Phase transitions and related electrochemical performances of Li-Rich layered cathode materials for high-energy lithium ion batteries. Journal of Alloys and Compounds, 732, 385-395. https://doi.org/10.1016/j.jallcom.2017.10.179