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采用水热法制备富锂相正极材料Li1+2xMn0.8Fe0.2P1-xB_xO4(x≤0.10),通过X射线衍射、激光粒度仪、扫描电子显微镜对所得样品进行表征。将所得正极材料组装成电池,采用恒流充放电、循环伏安和交流阻抗测试其电化学性能。结果表明:B原子进入晶格,取代P原子位置,形成固溶体。当B的取代量x=0.02时,富锂相正极材料Li1.04Mn0.8Fe0.2P0.98B0.02O4的电化学性能最好,0.1C时放电比容量为157.9 mA·h/g、5C时为102.7 mA·h/g,分别优于未经B掺杂的LiMn0.8Fe0.2PO4的149.7和85.3 mA·h/g。
Abstract：Lithium-rich Li1+2xMn0.8Fe0.2P1-xB_xO4(x≤0.10) cathode materials were synthesized via substitution with B on P-site by a hydrothermal method.The phase and crystal structures were investigated by X-ray diffraction,laser particle size analysis and scanning electron microscopy.The electrochemical properties,including galvanostatic charge/discharge property,cyclic voltammetry and alternating current impedance,were evaluated through assembled coin-type cells.The results show that B occupies P position into the lattice to form a solid solution.The Li-rich Li1.04Mn0.8Fe0.2P0.98B0.02O4 cathode materials show the optimum electrochemical performances,i.e.,a capacity of 157.9 mA·h/g at 0.1C and 102.7 mA·h/g at 5C,respectively,which are better than those without B doping.
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基本信息:
DOI：10.14062/j.issn.0454-5648.2017.01.01
中图分类号:TM912
引用信息:
[1]赵德,任丽,靳芳芳.B掺杂制备Li_(1+2x)Mn_(0.8)Fe_(0.2)P_(1-x)B_xO_4锂电池正极材料[J].硅酸盐学报,2017,45(01):1-8.DOI:10.14062/j.issn.0454-5648.2017.01.01.
基金信息:
国家自然科学基金项目(51203041)
2016-12-12
2016-12-12
2016-12-12