一氧化碳还原法制备磷酸铁锂—反应机理和动力学

doi:10.61558/2993-074X.1927

摘要/Abstract

摘要： 由CO还原FePO4和LiOH前驱体合成LiFePO4正极材料,应用XRD、SEM表征材料结构和形貌、充放电曲线测试电化学性能.结果表明,LiOH过量5%合成的LiFePO4样品颗粒度约200 nm,包覆碳后LiFePO4电极0.1C放电容量可达158 mAh/g.高温现场XRD对该合成反应作实时监控,借助时间分辨图谱分析,检测出Li3Fe2(PO4)3中间物.动力学研究表明成核与生长是该合成过程的速控步骤,反应活化能为89.44 kJ/mol.

关键词: 磷酸铁锂, 一氧化碳还原, 高温原位XRD, Li3Fe2(PO4)3, 机理, 动力学

Abstract: LiFePO4 cathode material was synthesized by CO reducing FePO4 and LiOH precursors.The structure,morphology and electrochemical performances of such LiFePO4 material were characterized by XRD,SEM and charge-discharge tests.It was shown that the particle size of the LiFePO4 synthesized with 5% excess of LiOH in the precursor was about 200 nm.By carbon coating,the LiFePO4 electrode was able to deliver a reversible capacity of 158 mAh·g-1 at 0.1C discharge rate.Temperature-programmed X-ray diffraction was employed to monitor the reaction during the formation of LiFePO4,and Li3Fe2(PO4)3 was found to be an intermediate by analyzing the time-resolved XRD patterns.Kinetic study indicates that nucleation and their growth is the rate-determining step in the process of the reaction and the activation energy of this reaction was 89.44 kJ/mol.

Key words: LiFePO4, CO reduction, temperature-programmed X-ray diffraction, Li3Fe2(PO4)3, mechanism, kinetics

中图分类号:

TM912.9

陈赟华, 杨勇, . 一氧化碳还原法制备磷酸铁锂—反应机理和动力学[J]. 电化学（中英文）, 2008, 14(4): 388-393.

CHEN Yun-hua, YANG Yong. Synthesis of the LiFePO_4 by CO Reduction:Reaction Mechanism and Kinetics[J]. Journal of Electrochemistry, 2008, 14(4): 388-393.

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链接本文: https://electrochem.xmu.edu.cn/CN/10.61558/2993-074X.1927

https://electrochem.xmu.edu.cn/CN/Y2008/V14/I4/388

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