采用水热辅助溶胶凝胶法及球磨包碳技术合成Li2CoxMn1-xSiO4(x=0、 0.1、0.3、0.5、1)与碳纳米管复合材料,X 射线衍射(XRD) 、扫描电镜(SEM)表征复合材料的结构与形貌。用循环伏安(CV) ,交流阻抗(EIS) ,充放电曲线测试材料的电化学性能,并与 Li2MnSiO4/C 和 Li2CoSiO4/C 进行对比。掺钴可以改善Li2MnSiO 4电极的倍率放电性能。
王琳
,
吕东平
,
杨勇
. 锂离子电池正极材料 Li2CoxMn1-xSiO4的合成及电化学性能研究[J]. 电化学, 2011
, 17(3)
: 318
-322
.
DOI: 10.61558/2993-074X.2847
We have successfully synthesized Li2CoxMn1-xSiO4/C (x=0, 0.1, 0.3, 0.5, 1)/C composites using hydrothermal assisted sol-gel process and ball-milling method. The results of X-ray diffraction show that the solid solutions of Li2CoxMn1-xSiO4 can be achieved when x≤0.3. The initial capacities increase from 70 mAhg-1??? of Li2MnSiO4/C to 105 mAhg-1??? of Li2Co0.3Mn0.7SiO4/C. Cyclic Voltammetry (CV) curves show that the replacement of Mn with Co can reduce the electrochemical polarization, making the insertion-extraction reaction of Li+ much easier. EIS results also prove that Co can decrease the charge transfer impedance of the materials.
[1] Armand M,Tarascon J M. Building better batteries [J]. Nature,2008,451(7179):652-657.
[2] Dominko R,Bele M,Gaberscek M, et al. Structure and electrochemical performance of Li2MnSiO4 and Li2FeSiO4 as potential Li-battery cathode materials [J]. Electrochemistry Communications,2006,8(2):217-222.
[3] Padhi A K,Nanjundaswamy K S,Goodenough J B. Phospho-olivines as positive-electrode materials for rechargeable lithium batteries [J]. Journal of the Electrochemical Society,1997,144(4):1188-1194.
[4] Armand M. Lithium insertion electrode materials based on orthosilicate derivatives:United State Patent,6085015[P].
[5] Gong Z L,Li Y X,Yang Y. Synthesis and characterization of Li2MnxFe1-xSiO4 as a cathode material for lithium-ion batteries [J]. Electrochemical and Solid State Letters,2006,9(12):A542-A544.
[6] Li Y X,Gong Z L,Yang Y. Synthesis and characterization of Li2MnSiO4/C nanocomposite cathode material for lithium ion batteries [J]. Journal of Power Sources,2007,174(2):528-532.
[7] Nyten A,Abouimrane A,Armand M, et al. Electrochemical performance of Li2FeSiO4 as a new Li-battery cathode material [J]. Electrochemistry Communications,2005,7(2):156-160.
[8] Gong Z L,Li Y X,He G N, et al. Nanostructured Li2FeSiO4 electrode material synthesized through hydrothermal-assisted sol-gel process [J]. Electrochemical and Solid State Letters,2008,11(5):A60-A63.
[9] Dominko R,Bele M,Kokalj A, et al. Li2MnSiO4 as a potential Li-battery cathode material [J]. Journal of Power Sources,2007,174(2):457-461.
[10] Gong Z L,Li Y X,Yang Y. Synthesis and electrochemical performance of Li2CoSiO4 as cathode material for lithium ion batteries [J]. Journal of Power Sources,2007,174(2):524-527.
[11] Armstrong A R,Lyness C,Menetrier M, et al. Structural Polymorphism in Li2CoSiO4 Intercalation Electrodes: A Combined Diffraction and NMR Study [J]. Chemistry of Materials,2010,22(5):1892-1900.
[12] Gong Zheng-liang(龚正良).Study of Polyanion Orthosilicates as Cathode Materials for Lithium Ion Batteries[D].Ximen:Xiamen University,2007
[13] Wang Y G,Wang Y R,Hosono E J, et al. The design of a LiFePO4/carbon nanocomposite with a core-shell structure and its synthesis by an in situ polymerization restriction method [J]. Angewandte Chemie-International Edition,2008,47(39):7461-7465.
[14] Arora P,White R E,Doyle M. Capacity fade mechanisms and side reactions in lithium-ion batteries [J]. Journal of the Electrochemical Society,1998,145(10):3647-3667.