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Abstract

Stoichiometric Zr-doped lithium iron phosphate(LiFePO_(4)) cathode material was synthesized by a solid-state reaction in an inert atmosphere.The effects of doping content on the physical and electrochemical properties of as-synthesized cathode materials were investigated.The samples were characterized by powder X-ray diffraction(XRD),and their electrochemical performance was systematically measured by impedance response and constant current charge/discharge cycling tests.The results indicate that the low concentration Zr~(4+)doping does not affect the structure of the material but considerably improves its kinetics in terms of capacity delivery and cycle performance.At 0.1C discharging rate,the reversible specific capacities of the Li_(0.99)Zr_(0.01)FePO_(4)cathode material is 135.6mAh g~(-1).After 30 cycles,the capacity fade was only 3.8%.The cathode material also displays a better rate performance.

Keywords

LiFePO_(4), Cathode material, Doping, Electrochemical performance

Publication Date

2006-08-28

Online Available Date

2006-08-28

Revised Date

2006-08-28

Received Date

2006-08-28

References

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