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Updated: Aug 5, 2026
10:03
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Enhancing Mn(II)/Mn(IV) Redox Activity and Reducing Polarization of NASICON-Type Na3MnTi(PO4)3 Through Al-Doping
Mengyao Wang1, Hao Fan1, Ping Hu2
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|August 3, 2026
Summary
Aluminum doping enhances sodium-ion battery performance by reducing voltage polarization in NASICON-type cathode materials. The optimized Na3.05MnTi0.95Al0.05(PO4)3 compound shows improved capacity and cyclability for practical applications.
Area of Science:
- Materials Science
- Electrochemistry
- Solid-State Chemistry
Background:
- NASICON-type cathode materials offer stable structures and efficient Na+ diffusion pathways for sodium-ion batteries.
- Na3MnTi(PO4)3 (NMTP) exhibits voltage hysteresis and limited capacity due to anti-site defects.
- Developing high-performance cathode materials is crucial for advancing sodium-ion battery technology.
Purpose of the Study:
- To investigate the effect of Al-doping on the electrochemical properties of Na3MnTi(PO4)3.
- To reduce voltage polarization and enhance specific capacity in NASICON-type cathodes.
- To explore the potential of Al-doped NMTP as a cathode material for sodium-ion batteries.
Main Methods:
- Synthesis of Na3+xMnTi1-xAlx(PO4)3 (x = 0, 0.05, 0.1) compounds.
- Electrochemical characterization including cyclic voltammetry and galvanostatic charge-discharge cycling.
- In situ X-ray diffraction (XRD) and ex situ X-ray absorption spectroscopy (XAS) for structural and redox analysis.
Main Results:
- Na3.05MnTi0.95Al0.05(PO4)3 (NMTAP-0.05) exhibited optimal specific capacity and cyclability.
- Al-doping effectively reduced voltage polarization in the NASICON-type structure.
- In situ XRD indicated a combination of solid-solution and biphasic reaction mechanisms.
- Ex situ XAS confirmed reversible Mn2+/Mn4+ redox activity.
Conclusions:
- Al-doping is a viable strategy to mitigate defects and improve the electrochemical performance of NMTP cathodes.
- NMTAP-0.05 demonstrates significant potential as a high-performance cathode material for sodium-ion batteries.
- The findings provide valuable insights for designing advanced phosphate-based cathode materials.
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