Related Experiment Video
Updated: Jul 17, 2025
10:03
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
25.5K
Enhanced Li+ Diffusion and Lattice oxygen Stability by the High Entropy Effect in Disordered-Rocksalt Cathodes
Shuyu Zhou1,2, Yuxuan Sun1, Tong Gao1
1Shenzhen International Graduate School, Tsinghua University, University Town of Shenzhen Nanshan District, Shenzhen, 518055, China.
Angewandte Chemie (International Ed. in English)
|September 4, 2023
Summary
High entropy disordered rocksalt oxides (HE DRXs) improve Li-ion battery performance by enhancing Li+ diffusion and lattice oxygen stability. Integrating more transition metal species in HE DRXs increases capacity upon cycling.
Area of Science:
- Materials Science
- Electrochemistry
- Solid-state Chemistry
Background:
- Cation-disordered Rocksalt oxides (DRXs) are promising Li-ion battery cathode materials.
- High entropy strategies in Mn-based DRXs improve rate capability but face capacity degradation challenges.
Purpose of the Study:
- Investigate a new group of high entropy DRXs (HE DRX) based on Ni2+-Nb5+ pairs.
- Systematically study structural and chemical evolution with increasing transition metal (TM) species.
- Explain the role of crystal field stability energy in HE DRX formation.
Main Methods:
- Synthesis and characterization of HE DRXs.
- In situ and ex situ techniques for structural and chemical analysis.
- Theoretical calculations to understand mechanisms.
Main Results:
- HE DRXs with increasing TM species were successfully synthesized.
- Crystal field stability energy explains single Rocksalt solid solution formation.
- Synergistic TM effects enable charge compensation.
- Enhanced Li+ diffusion and lattice oxygen stability observed.
- Increased capacity upon cycling demonstrated.
Conclusions:
- Effective integration of TM species in HE DRXs enhances electrochemical performance.
- HE DRXs offer a promising pathway for advanced Li-ion battery cathodes.
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