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摘要
含聚阴离子基团的锂离子电池正极材料硅酸亚铁锂(Li2FeSiO4)因其稳定的循环性能和优异的安全性能、且材料廉价、对环境友好得到了人们的广泛重视和研究。以硅酸锂(Li2SiO3)纳米棒-微米空球(Li2SiO3 NR-MS)为前驱体,使用流变相合成法成功合成了纯相的硅酸铁锂(Li2FeSiO4/C)。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)对Li2FeSiO4/C材料进行了表征,并用恒电流充放电测试了其作为锂离子电池正极材料的电化学性能。研究结果表明:Li2FeSiO4/C能继承前驱体的微球形貌,在室温,0.1C条件下,Li2FeSiO4/C首圈的充电比容量为142.2mAh/g,放电比容量为141.8mAh/g,库伦效率高达99.7%;循环40圈后放电比容量为136.5mAh/g,放电比容量损失率为3.8%。
Abstract
Li2FeSiO4 anode material of lithium ion batteries containing poly (anionic group) has attracted extensive attention and research because of its stable cycle and excellent safety performance,and its low cost and friendly environment.Li2SiO3 nanorods (Li2SiO3 NR-MS-micron hollow spheres) as a precursor for the first time using rheological phase reaction method,lithium iron silicate phase pure Li2FeSiO4/C was successfully synthesized.Li2FeSiO4/C materials were characterized by X ray diffraction (XRD),scanning electron microscopy (SEM),transmission electron microscopy (TEM).by constant current charge discharge test,its electrochemical performance as anode material for lithium ion battery was studied.The results showws that Li2FeSiO4/C synthesized with Li2SiO3nanorods and micrometer spheres can inherit the microsphere morphology of precursor.Under 0.1C current density,the first cycle charge capacity was 142.2 mAh/g,and discharge capacity was 141.8 mAh/g,the coulomb efficiency was up to 99.7%.After 40 cycles,the stable discharge specific capacity of 136.5mAh/g can be obtained,the loss ratio of discharge capacity was 3.8%.
关键词
锂离子电池
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Li2FeSiO4
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电化学性能
Key words
lithium battery
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Li2FeSiO4/C
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electrochemical property
以Li2SiO3纳米棒-微米球为前驱体合成的Li2FeSiO4/C材料及其电性能的研究[J].
化工新型材料, 2018, 46(11): 108-110 DOI:
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基金资助
湖北省自然科学基金项目(2014CKC526)
