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Updated: Jun 17, 2026
10:03
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Alkali-site lithium doping enables a high-performance Na3Fe2(PO4)(P2O7) cathode for sodium-ion batteries
Zijun Sun1, Wenzhu Cao1, Xiyang Hu1
1Institute of Nanoscience and Nanotechnology, School of Physical Science and Technology, Central China Normal University, Wuhan 430079, China. yz@ccnu.edu.cn.
Dalton Transactions (Cambridge, England : 2003)
|June 16, 2026
Summary
Trace lithium substitution in iron-based polyanionic cathodes enhances sodium-ion battery performance. This strategy improves sodium-ion diffusion and stability for advanced energy storage applications.
Area of Science:
- Materials Science
- Electrochemistry
- Solid-State Chemistry
Background:
- Iron-based polyanionic Na3Fe2(PO4)(P2O7) (N3F2PP) is a promising cathode material for sodium-ion batteries (SIBs) due to its low cost and structural integrity.
- However, N3F2PP suffers from slow sodium-ion diffusion kinetics and limited usable capacity, hindering its practical implementation.
Purpose of the Study:
- To enhance the electrochemical performance of iron-based polyanionic cathodes for SIBs.
- To address the limitations of sluggish Na+ diffusion and low capacity in N3F2PP through a novel substitution strategy.
Main Methods:
- A trace lithium (Li+) substitution strategy was employed at the alkali sites of N3F2PP.
- The structural and electrochemical properties of the modified cathode material, Na2.95Li0.05Fe2(PO4)(P2O7)@C (NLF2PP@C-0.05), were investigated.
Main Results:
- Li+ substitution induced localized lattice contraction, optimizing the local structure and promoting Na+ transport.
- The Li+ incorporation alleviated lattice strain during the Fe2+/Fe3+ redox reaction, improving structural stability.
- The optimized NLF2PP@C-0.05 cathode exhibited a high discharge capacity (113.2 mAh g-1 at 0.1 C), excellent rate capability (84.1 mAh g-1 at 20 C), and superior cycling stability (97.5% retention after 2000 cycles at 20 C).
Conclusions:
- Alkali-site substitution is a viable strategy for improving polyanionic cathode materials in SIBs.
- This approach offers an effective alternative to traditional Fe-site modification methods for enhancing battery performance.
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