高温固相法制备LiFePO_4/C正极材料及其性能
|
摘要
为了提高磷酸铁锂的能量密度,本文通过两步高温固相反应法合成了锂离子电池正极LiFePO_4/C复合材料,利用XRD、SEM、TEM等方法对该正极材料的晶体结构、表面形貌进行了分析研究。实验结果表明,LiFePO_4/C具有单一的橄榄石结构,通过掺杂前驱体10%(质量分数)的葡萄糖合成的材料具有良好的充放电性能和循环稳定性能球状,LiFePO4为锂离子的迁移和扩散提供了通道,有利于电化学性能的提升。在0.1 C倍率下进行充放电测试,首次放电比容量可达161 m Ahg-1,在2 C下循环了100次后复合材料的容量为148 m Ahg~(-1),库仑效率高达98%,结果表明碳包覆的LiFePO_4样品的电化学性能得到了很大提高。
In this paper,the cathode LiFePO_4/C composite material of being used in inlithium ion battery was synthesized by two-step high temperature solid state reaction. The crystal structure and morphology of the LiFePO_4/C were characterized by X-ray diffraction( XRD),scanning electron microscopy( SEM) and transmission electron microscope( TEM). The experimental results show that LiFePO_4/C has a single olivine structure,The materials synthesized by doping 10%( mass fraction) of glucose precursor have good charge-discharge performance and cyclic stability. The spheroidal LiFePO_4 Provides a channel for the transport and diffusion of lithium ions,which is beneficial to the improvement of electrochemical performance.The charge-discharge test at a rate of0.1 C shows that the initial discharge specific capacity can reach 161 m Ahg~(-1),The capacity of the composite after100 cycles is 148 m Ahg~(-1) at 2 C,Coulomb efficiency is 98%.The results show that the electrochemical properties of carbon-coated lithium iron phosphate samples has been greatly improved.
In this paper,the cathode LiFePO_4/C composite material of being used in inlithium ion battery was synthesized by two-step high temperature solid state reaction. The crystal structure and morphology of the LiFePO_4/C were characterized by X-ray diffraction( XRD),scanning electron microscopy( SEM) and transmission electron microscope( TEM). The experimental results show that LiFePO_4/C has a single olivine structure,The materials synthesized by doping 10%( mass fraction) of glucose precursor have good charge-discharge performance and cyclic stability. The spheroidal LiFePO_4 Provides a channel for the transport and diffusion of lithium ions,which is beneficial to the improvement of electrochemical performance.The charge-discharge test at a rate of0.1 C shows that the initial discharge specific capacity can reach 161 m Ahg~(-1),The capacity of the composite after100 cycles is 148 m Ahg~(-1) at 2 C,Coulomb efficiency is 98%.The results show that the electrochemical properties of carbon-coated lithium iron phosphate samples has been greatly improved.
引文
[1]Yang C C,Hsu Y H,Shih J Y,et al.Preparation of 3D micro/mesoporous Li Fe PO4,composite wrapping with porous graphene oxide for high-power lithium ion battery[J].Electrochimica Acta,2017:S001346861732488X.
[2]Zhao J W,Zhao S X,Wu X,et al.Double role of silicon in improving the rate performance of Li Fe PO4,cathode materials[J].Journal of Alloys&Compounds,2017,699:849-855.
[3]Wang B,Liu A,Abdulla W A,et al.Desired crystal oriented Li FePO\r,4\r,nanoplatelets in situ anchored on a graphene crosslinked conductive network for fast lithium storage[J].Nanoscale,2015,7(19):8819-8828.
[4]Song J,Wang L,Shao G,et al.Controllable synthesis,morphology evolution and electrochemical properties of Li Fe PO4cathode materials for Li-ion batteries.[J].Physical Chemistry Chemical Physics Pccp,2014,16(17):7728-7733.
[5]Wang J,Sun X.Olivine Li Fe PO4:the remaining challenges for future energy storage[J].Energy&Environmental Science,2015,8(4):1110-1138.
[6]Bazzi K,Nazri M,Naik V M,et al.Enhancement of electrochemical behavior of nanostructured Li Fe PO4/Carbon cathode material with excess Li[J].Journal of Power Sources,2016,306:17-23.
[7]陈召勇,张建利,朱华丽,et al.Li Fe PO4的制备及其充放电过程中的结构演变和性能研究[J].合成化学,2009,17(4):422-427.
[8]Zhou X,Wang F,Zhu Y,et al.Graphene modified Li Fe PO4cathode materials for high power lithium ion batteries[J].JOURNALOF MATERIALS CHEMISTRY,2011,21(10):3353-0.
[9]Hu Q,Liao J Y,Zou B K,et al.Improving the rate and low-temperature performance of Li Fe PO4by tailoring the form of carbon coating from amorphous to graphene-like[J].Journal of Solid State Electrochemistry,2017.
[10]Kim M S,Lee G W,Lee S W,et al.Synthesis of Li Fe PO4/graphene microspheres while avoiding restacking of graphene sheet’s for high-rate lithium-ion batteries[J].Journal of Industrial and Engineering Chemistry,2017:S1226086X17301715.
[11]Fathollahi F,Javanbakht M,Omidvar H,et al.Improved electrochemical properties of Li Fe PO4/graphene cathode nanocomposite prepared by one-step hydrothermal method[J].Journal of Alloys and Compounds,2015,627:146-152.
[12]High performance Li Fe PO4microsphere composed of nanofibers with an alcohol-thermal approach[J].Journal of Materials Chemistry A,2013,1.
[13]Eftekhari,Ali.Li Fe PO4/C nanocomposites for lithium-ion batteries[J].Journal of Power Sources,2017,343:395-411.
[14]Nitta N,Wu F,Lee J T,et al.Li-ion battery materials:present and future[J].Materials Today,2015,18(5):252-264.
[15]He L,Zha W,Chen D.Crystal growth kinetics,microstructure and electrochemical properties of Li Fe PO4/carbon nanocomposites fabricated using a chelating structure phosphorus source[J].Rsc Advances,2018,8(6):3151-3160.
[16]Yang J,Wang J,Wang D,et al.3D porous Li Fe PO4/graphene hybrid cathodes with enhanced performance for Li-ion batteries[J].Journal of Power Sources,2012,208(none):340-344.
[17]Ding Y,Jiang Y,Xu F,et al.Preparation of nano-structured Li Fe PO4/graphene composites by co-precipitation method[J].E-lectrochemistry Communications,2010,12(1):10-13.
[2]Zhao J W,Zhao S X,Wu X,et al.Double role of silicon in improving the rate performance of Li Fe PO4,cathode materials[J].Journal of Alloys&Compounds,2017,699:849-855.
[3]Wang B,Liu A,Abdulla W A,et al.Desired crystal oriented Li FePO\r,4\r,nanoplatelets in situ anchored on a graphene crosslinked conductive network for fast lithium storage[J].Nanoscale,2015,7(19):8819-8828.
[4]Song J,Wang L,Shao G,et al.Controllable synthesis,morphology evolution and electrochemical properties of Li Fe PO4cathode materials for Li-ion batteries.[J].Physical Chemistry Chemical Physics Pccp,2014,16(17):7728-7733.
[5]Wang J,Sun X.Olivine Li Fe PO4:the remaining challenges for future energy storage[J].Energy&Environmental Science,2015,8(4):1110-1138.
[6]Bazzi K,Nazri M,Naik V M,et al.Enhancement of electrochemical behavior of nanostructured Li Fe PO4/Carbon cathode material with excess Li[J].Journal of Power Sources,2016,306:17-23.
[7]陈召勇,张建利,朱华丽,et al.Li Fe PO4的制备及其充放电过程中的结构演变和性能研究[J].合成化学,2009,17(4):422-427.
[8]Zhou X,Wang F,Zhu Y,et al.Graphene modified Li Fe PO4cathode materials for high power lithium ion batteries[J].JOURNALOF MATERIALS CHEMISTRY,2011,21(10):3353-0.
[9]Hu Q,Liao J Y,Zou B K,et al.Improving the rate and low-temperature performance of Li Fe PO4by tailoring the form of carbon coating from amorphous to graphene-like[J].Journal of Solid State Electrochemistry,2017.
[10]Kim M S,Lee G W,Lee S W,et al.Synthesis of Li Fe PO4/graphene microspheres while avoiding restacking of graphene sheet’s for high-rate lithium-ion batteries[J].Journal of Industrial and Engineering Chemistry,2017:S1226086X17301715.
[11]Fathollahi F,Javanbakht M,Omidvar H,et al.Improved electrochemical properties of Li Fe PO4/graphene cathode nanocomposite prepared by one-step hydrothermal method[J].Journal of Alloys and Compounds,2015,627:146-152.
[12]High performance Li Fe PO4microsphere composed of nanofibers with an alcohol-thermal approach[J].Journal of Materials Chemistry A,2013,1.
[13]Eftekhari,Ali.Li Fe PO4/C nanocomposites for lithium-ion batteries[J].Journal of Power Sources,2017,343:395-411.
[14]Nitta N,Wu F,Lee J T,et al.Li-ion battery materials:present and future[J].Materials Today,2015,18(5):252-264.
[15]He L,Zha W,Chen D.Crystal growth kinetics,microstructure and electrochemical properties of Li Fe PO4/carbon nanocomposites fabricated using a chelating structure phosphorus source[J].Rsc Advances,2018,8(6):3151-3160.
[16]Yang J,Wang J,Wang D,et al.3D porous Li Fe PO4/graphene hybrid cathodes with enhanced performance for Li-ion batteries[J].Journal of Power Sources,2012,208(none):340-344.
[17]Ding Y,Jiang Y,Xu F,et al.Preparation of nano-structured Li Fe PO4/graphene composites by co-precipitation method[J].E-lectrochemistry Communications,2010,12(1):10-13.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |