This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the compos...This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the composites are summarized in detail. The structural and morphology characters of graphene sheets that may affect the property of the composites are discussed briefly. The possible ongoing researches in area are speculated upon.展开更多
The article developed a lithium iron phosphate - composite cathode material of lithium vanadium phosphate. Using X-ray diffraction (XRD), electronic scanning electron microscopy surface (SEM), laser particle size ...The article developed a lithium iron phosphate - composite cathode material of lithium vanadium phosphate. Using X-ray diffraction (XRD), electronic scanning electron microscopy surface (SEM), laser particle size analyzer, carbon and sulfur analyzer, and X-ray photoelectron spectroscopy, etc. for the prepared composites were characterized and found the material is mainly crystalline structure of lithium iron phosphate, and lithium vanadium, wherein a small amount of impurities; finer particle size of the material, the particle size distribution is narrow and uniform, smooth particle surface, wrapping in good carbon composite with other materials prepared in comparison the case has a carbon content of about optimum conductivity. To assemble the material into a cell after the 0.1C, IC, 2C when and 5C, the first discharge capacity were 160,145,127 and 109 mA·h·g^-1, after 50 cycles, the discharge capacity of 162, respectively, 144,126 and 106 mA·h·g^-1, which showed good rate characteristics and cycle characteristics.展开更多
以Fe SO4·7H2O、NH4H2PO4、H2O2、Li2CO3、C6H12O6和自制的氧化石墨烯(GO)为原料,分别采用原位包覆法和非原位包覆法制备了石墨烯磷酸铁锂样品:Li Fe PO4/C/G-1和Li Fe PO4/C/G-2。用X射线衍射(XRD)、扫描电镜(SEM)、透射...以Fe SO4·7H2O、NH4H2PO4、H2O2、Li2CO3、C6H12O6和自制的氧化石墨烯(GO)为原料,分别采用原位包覆法和非原位包覆法制备了石墨烯磷酸铁锂样品:Li Fe PO4/C/G-1和Li Fe PO4/C/G-2。用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、交流阻抗(EIS)和充放电测试研究了两种包覆方法制备的样品的晶体结构、形貌和电化学性能。结果表明原位法包覆所得复合材料Li Fe PO4/C/G-1具有更优秀的电性能:在2.5~4.1 V充放电,0.1C和1C首次放电比容量分别为158.15和150.5 m Ah·g-1,在1C倍率下循环500次后容量保持率达到98.3%。展开更多
以固相法制备出了磷酸亚铁锂-磷酸钒锂复合正极材料。采用X-射线衍射仪(XRD)、电子扫面电镜(SEM)、激光粒度分析仪、碳硫分析仪以及X-光电子能谱仪等对制备出的复合材料进行表征,发现该材料以磷酸亚铁锂和磷酸钒锂的晶形结构为主,其中...以固相法制备出了磷酸亚铁锂-磷酸钒锂复合正极材料。采用X-射线衍射仪(XRD)、电子扫面电镜(SEM)、激光粒度分析仪、碳硫分析仪以及X-光电子能谱仪等对制备出的复合材料进行表征,发现该材料以磷酸亚铁锂和磷酸钒锂的晶形结构为主,其中有少量的杂质成分;该材料颗粒粒度较细、粒度分布窄且均匀,颗粒表面光滑、碳包裹状况良好,同其它方法制备的复合材料比较在碳含量差不多的情况下具有较优的导电率。对材料进行了电化学性能表征认为该材料的电化学性能比较优异,0.1 C放电容量达到190 mA h g 1以上,10 C可以达到120 mA h g 1,20 C放电容量仍有85 mA h g 1且循环稳定性均较好;1 C进行1000次循环之后仍然保持120 mA h g 1的容量,具有较高的实用价值。展开更多
基金the Science and Technology Commission of Shanghai Municipality (No. 12nm0503500)the National Science Foundation of China (Nos. 21376148, 11374205)
文摘This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the composites are summarized in detail. The structural and morphology characters of graphene sheets that may affect the property of the composites are discussed briefly. The possible ongoing researches in area are speculated upon.
文摘The article developed a lithium iron phosphate - composite cathode material of lithium vanadium phosphate. Using X-ray diffraction (XRD), electronic scanning electron microscopy surface (SEM), laser particle size analyzer, carbon and sulfur analyzer, and X-ray photoelectron spectroscopy, etc. for the prepared composites were characterized and found the material is mainly crystalline structure of lithium iron phosphate, and lithium vanadium, wherein a small amount of impurities; finer particle size of the material, the particle size distribution is narrow and uniform, smooth particle surface, wrapping in good carbon composite with other materials prepared in comparison the case has a carbon content of about optimum conductivity. To assemble the material into a cell after the 0.1C, IC, 2C when and 5C, the first discharge capacity were 160,145,127 and 109 mA·h·g^-1, after 50 cycles, the discharge capacity of 162, respectively, 144,126 and 106 mA·h·g^-1, which showed good rate characteristics and cycle characteristics.
文摘以Fe SO4·7H2O、NH4H2PO4、H2O2、Li2CO3、C6H12O6和自制的氧化石墨烯(GO)为原料,分别采用原位包覆法和非原位包覆法制备了石墨烯磷酸铁锂样品:Li Fe PO4/C/G-1和Li Fe PO4/C/G-2。用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、交流阻抗(EIS)和充放电测试研究了两种包覆方法制备的样品的晶体结构、形貌和电化学性能。结果表明原位法包覆所得复合材料Li Fe PO4/C/G-1具有更优秀的电性能:在2.5~4.1 V充放电,0.1C和1C首次放电比容量分别为158.15和150.5 m Ah·g-1,在1C倍率下循环500次后容量保持率达到98.3%。
文摘以固相法制备出了磷酸亚铁锂-磷酸钒锂复合正极材料。采用X-射线衍射仪(XRD)、电子扫面电镜(SEM)、激光粒度分析仪、碳硫分析仪以及X-光电子能谱仪等对制备出的复合材料进行表征,发现该材料以磷酸亚铁锂和磷酸钒锂的晶形结构为主,其中有少量的杂质成分;该材料颗粒粒度较细、粒度分布窄且均匀,颗粒表面光滑、碳包裹状况良好,同其它方法制备的复合材料比较在碳含量差不多的情况下具有较优的导电率。对材料进行了电化学性能表征认为该材料的电化学性能比较优异,0.1 C放电容量达到190 mA h g 1以上,10 C可以达到120 mA h g 1,20 C放电容量仍有85 mA h g 1且循环稳定性均较好;1 C进行1000次循环之后仍然保持120 mA h g 1的容量,具有较高的实用价值。