采用超声辅助溶液法在尖晶石LiMn2O4表面包覆TiO2.通过X射线衍射、扫描电子显微镜、恒电流充放电、交流阻抗技术分析合成材料的结构、形貌及电化学性能.结果表明:TiO2包覆LiMn2O4与LiMn2O4具有相似的X射线衍射结果,衍射峰尖锐,样品颗粒大小均匀,无明显团聚.室温下0.2C充放电时,表面包覆1％TiO2的LiMn2O4首次放电比容量为123.51 mAh·g-1,略低于未包覆LiMn2O4的124.02 mAh·g-1,但在2C和4C高倍率时,表面包覆1％TiO2的LiMn2O4比容量分别为105.54和80.73 mAh·g-1,远高于未包覆的79.76和66.37 mAh·g -1.室温及55℃下以0.2C倍率循环50后,表面包覆1％ TiO2的LiMn2O4容量保持率分别为91.69％和87.36％,远高于未包覆LiMn2O4的86.58％和78.02％.室温下以1C倍率循环100次后,表面包覆1％ TiO2的容量保持率比未包覆LiMn2O4高出3.75％.表面包覆TiO2后LiMn2O4的循环性能得到了大大的提高,尤其是高温循环性能.
参考文献
| [1] | Jianlin Li;Claus Daniel;David Wood .Materials processing for lithium-ion batteries[J].Journal of Power Sources,2011(5):2452-2460. |
| [2] | Chung KY;Kim JH;Yoon WS;Kim HS;Cho BW;Kim KB .The condition for the evolution of extra current peak in the cyclic voltammogram of LixMn2O4 investigated by in situ bending beam method[J].Electrochemistry communications,2009(1):212-215. |
| [3] | LIU Yunjian,GUO Huajun,LI Xinhai,WANG Zhixing.Improving the electrochemical performance of LiMn2O4/graphite batteries using LiF additive during fabrication[J].稀有金属(英文版),2011(02):120-125. |
| [4] | 乔亚非,李新丽,连芳,李福燊,仇卫华.LiMnxNixCo1-2xO2的自蔓延燃烧合成及电化学性能研究[J].稀有金属,2011(04):491-497. |
| [5] | Chung K Y;Kim K B .Investigations into capacity fading as a result of a Jahn-Teller distortion in 4 V LiMr2O4 thin film electrodes[J].Electrochimica Acta,2004,49(20):3327. |
| [6] | Wu H C;Guo Z Z;Wen H P;Yang M H .Study the fading mechanism of LiMn2O4 battery with spherical and flake type graphite as anode materials[J].Journal of Power Sources,2005,146(1-2):736. |
| [7] | Sun Y K;Yoon C S;Oh I H .Surface structural change of ZnO-coated LiNi0.5 Mn1 5O4 spinel as 5 V cathode materials at elevated temperatures[J].Electrochimica Acta,2003,48(05):503. |
| [8] | Ah Reum Han;Tae Woo Kim;Dae Hoon Park;Seong-Ju Hwang;Jin-Ho Choy .Soft Chemical Dehydration Route to Carbon Coating of Metal Oxides: Its Application for Spinel Lithium Manganate[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2007(30):11347-11352. |
| [9] | Tu J;Zhao X B;Cao G S;Tu J P,Zhu T J .Improved performance of LiMn2O4 cathode materials for lithium ion batteries by gold coating[J].Materials Letters,2006,60(27):3251. |
| [10] | J. S. Gnanaraj;V. G. Pol;A. Gedanken;D. Aurbach .Improving the high-temperature performance of LiMn_2O_4 spinel electrodes by coating the active mass with MgO via a sonochemical method[J].Electrochemistry communications,2003(11):940-945. |
| [11] | Lee S W;Kim K S;Lee K L;Moon H S,Kim H J,Cho B W,Cho W I,Park J W .Electrochemical characteristics of metal oxide-coated lithium manganese oxide (spinel type) Part Ⅱ.In the range of 3 0 ～4 4 V[J].Journal of Power Sources,2004,130(1-2):233. |
| [12] | Ha H W;Yun N J;Kim K .Improvement of electrochemical stability of LiMn2O4 by CeO2 coating for lithium-ion batteries[J].Electrochimica Acta,2007,52(09):3236. |
| [13] | Lim S;Cho J .PVP-Assisted ZrO2 coating on LiMn2O4 spinel cathode nanoparticles prepared by MnO2 nanowire templates[J].Electrochemistry communications,2008(10):1478-1481. |
| [14] | Tu J;Zhao X B;Xie J;Cao G S,Zhuang D G,Zhu T J,Tu J P .Enhanced low voltage cycling stability of LiMn2O4 cathode by ZnO coating for lithium ion batteries[J].Journal of Alloys and Compounds,2007,432(1-2):313. |
| [15] | Y.-K. Sun;K.-J. Hong;Jai Prakash;K. Amine .Electrochemical performance of nano-sized ZnO-coated LiNi_(0.5)Mn_(1.5)O_4 spinel as 5 V materials at elevated temperatures[J].Electrochemistry communications,2002(4):344-348. |
| [16] | LIU Wengang,XU Yunhua,YANG Rong.Synthesis and electrochemical properties of Li2MnSiO4/C nanoparticles via polyol process[J].稀有金属（英文版）,2010(05):511-514. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%