Abstract
Cathode materials LiFePO4 and LiFe0.9Mg0.1PO4 for lithium ion batteries were synthesized by a solid state reaction. Chemical oxidation to obtain Li0.4Fe0.9Mg0.1PO4 and Li0.1Fe0.9Mg0.1PO4 was carried out by reacting LiFe0.9Mg0.1PO4 with K2S2O8 solution of different concentration. Li0.1Fe0.9Mg0.1PO4 was confirmed to be a single phase compound with no impure phases,investigated by X-ray diffraction (XRD),selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM) techniques. Calculated lattice parameter results showed decreased lattice misfit between lithiated LiFe0.9Mg0.1PO4 and delithiated Li0.1Fe0.9Mg0.1PO4,compared lattice misfit between LiFePO4 and FePO4. It was considered the decreased lattice misfit as the structural basis for optimized high-rate capability of cathode material LiFe0.9Mg0.1PO4 for lithium ion batteries.
Keywords
lithium ion battery, lithium iron phosphate, phase transformation, kinetic behavior, lattice misfit
Publication Date
2009-08-28
Online Available Date
2009-08-28
Revised Date
2009-08-28
Received Date
2009-08-28
Recommended Citation
Lin HU, Zheng LI, Zhao-qiang ZENG.
Structural Basis for High-rate Capability of Cathode Material Li_(0.1)Fe_(0.9)Mg_(0.1)PO_4[J]. Journal of Electrochemistry,
2009
,
15(3): 250-254.
DOI: 10.61558/2993-074X.1989
Available at:
https://jelectrochem.xmu.edu.cn/journal/vol15/iss3/3
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