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Updated: May 27, 2025
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Formation and Variation of the Superstructure of Cation Ordering in Layered Cathode Materials
Yilin Tai1, Guojie Chen2, Yangsheng Li3
1Information Materials and Intelligent Sensing Laboratory of Anhui Province, Leibniz International Joint Research Center of Materials Sciences of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Abstract:
This study employs aberration-corrected transmission electron microscopy to provide definitive evidence of cation ordering within the superstructure of LiNi0.5Co0.2Mn0.3O2 (NCM523), a prominent Ni-rich ternary cathode material, characterized by wave vector = 1/3(2a* - *). We show that this ordering can be enhanced through controlled heating. Comparative analysis of LiNiCoMnO2 samples with different compositions revealed that Mn ions are crucial for superstructure formation. The battery performance test shows that the superstructure has no obvious effect on the voltage platform during the charge-discharge cycle, but has a negative effect on the cycle performance and structural stability. This study elucidates the origin and detrimental effects of superstructures, advancing the understanding of their impact on battery performance, which is vital for the future development of ternary cathode materials.
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