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研究论文

尖晶石LiMn_2O_4的表面改性研究

  • 张仁刚 ,
  • 赵世玺 ,
  • 夏君磊 ,
  • 刘韩星
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  • 武汉理工大学材料复合新技术国家重点实验室,武汉理工大学材料复合新技术国家重点实验室,武汉理工大学材料复合新技术国家重点实验室,武汉理工大学材料复合新技术国家重点实验室 湖北武汉430070 ,湖北武汉430070 ,湖北武汉430070 ,湖北武汉430070

收稿日期: 2002-08-28

  修回日期: 2002-08-28

  网络出版日期: 2002-08-28

Study on Modification of spinel LiMn_2O_4 by Overcoating

  • ZHANG Ren_gang ,
  • ZHAO Shi_xi ,
  • XIA Jung_lei ,
  • LIU Han_xing
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  • (Stata Labo. of Advanced Techn. for Materials synthesis and processing,Wuhan Univ. of Techn.,Wuhan, 430070,China

Received date: 2002-08-28

  Revised date: 2002-08-28

  Online published: 2002-08-28

摘要

采用溶胶_凝胶法合成尖晶石LiMn2 O4 ,并以LiCoO2 对其进行包覆 ,用XRD、SEM、EPMA等方法对修饰的尖晶石结构和性能进行研究 .结果表明 ,经包覆的LiMn2 O4 在 70 0℃焙烧 10h所得的晶粒是表层富含Co的立方尖晶石 ,而且晶粒中Co3+的含量呈现出从表到里递减的梯度分布 .以该材料作锂离子电池正极 ,虽初始容量稍有降低 ,但能有效地降低Mn2 +在电解质中的溶解 ,而且对Jahn_Teller效应有一定的抑制作用 ,包覆的LiMn2 O4 尖晶石正极材料比未包覆的有更好的循环性能

本文引用格式

张仁刚 , 赵世玺 , 夏君磊 , 刘韩星 . 尖晶石LiMn_2O_4的表面改性研究[J]. 电化学, 2002 , 8(3) : 269 -274 . DOI: 10.61558/2993-074X.3296

Abstract

The surface of spinel LiMn 2O 4 was modified by the sol_gel process with LiCoO 2_coated LiMn 2O 4 and studied by XRD,SEM and EPMA.The results have shown that the surface of the coated grains heated at 700 ℃ for 10h,which is cubic spinel,were Co_rich.The amount of Co 3+ in the grains changed owing to different place of the grain and decreased from surface to inner parts. Using the coated as the cathode of Li_ion cells,the initial capacity deceased slightly,but the amount of Mn 2+ solving in electrolyte decreased,Jahn_Teller effect was suppressed to a certain extent.The LiCoO 2_coated LiMn 2O 4 showed better cycling performance than the bare spinel LiMn 2O 4.

参考文献

[1] WeiWeiHuang,RogerFrech.InsituRamanspectroscopicstudiesofelectrochemicalintercalationinLixMn2O4_basedcathodes[J].J .PowerSources,1999,81-82:616~620. [2] MyoungYoupSang,DongSuAhn,HyeRyoungPark.CapacityfadingofspinelphaseLiMn2O4 withcycling[J].J.PowerSources,1999,83:57~60. [3] LiGuohua,H .Ikuta,T .Uchida,etal.ThespinelphasesLiMyMn2-yO4(M =Co,Cr,Ni)asthecathodeforrechargeablelithiμmbatteries[J].J .Electrochemic.Soc.,1996,143(1):178~182. [4] LourdesHernan,JulianMorales,LuisSanchez,etal.UseofLi_M_Mn_O[M =Co,Cr,Ti]spinelspreparedbyasol_gelmethodeascathodesinhigh_voltagelithiμmbatteries[J].SolidStataIonics,1999,118:179~185. [5] M .R .Palacin,F .LeCras,L .Seguin,etal.Insitustructuralstudyof4v_rangelithiμmextraction/insertioninfluorine_substitutedLiMn2O4[J].J .SolidStataChemistry,1999,144:361~371. [6] JaephilCho,GeunbaeKim.EnhancementofthermalstabilitiyofLiCoO2 byLiMn2O4 coating[J].Electro chemicalandSolid_StataLetters,1999,2(6):253~255. [7] Ho_JinKweon,SueJooKim,DongGonPork.ModificationofLi1-xNi1- yCoyO2 byapplyingasurfacecoat ingofMgO[J].J.PowerSources,2000,88:255~261. [8] LeeYun_sung,SunYang_Kook,NahmKee_Suk.SynthesisofspinelLiMn2O4 cathodematerialpreparedbyandadipicacid_assistedsol_gelmethodforlithiμmsecondarybatteries[J].SolidStateIonics,1998,109:285~294. [9] WangGX ,BradhurstDH ,LiuHK ,etal.ImprovementofelectrochemicalpropertiesofthespinelLiMn2O4 usingaCrdopanteffect[J].SolidStateIonics,1999,120:96~98.
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