溶液法合成锂离子电池的阴极材料LiZn_xNi_(0.5-x)Mn_(1.5)O_4及其电化学性质研究  

Synthesis and electrochemical properties of LiZn_xNi_(0.5-x)Mn_(1.5)O_4 as cathode material for lithium-ion battery

作　　者：陈宇[1] 何锋[1] 张玉荣[1] 

机构地区：[1]福州大学化学系,福建福州350002

出　　处：《功能材料》2006年第4期653-657,共5页Journal of Functional Materials

基　　金：FinancialSupportofthisworkbytheScienceandTechnologyDepartmentofFujianProvince(2001J019);FuzhouUniversityareGreatlyAcknowledged(2003-XQ-06)

摘　　要：采用共沉淀法及溶胶一凝胶法合成了锂离子电池的阴极材料LiZnxNi0.5-xMn1.5O4（0．01≤x≤0．09）。结构研究结果表明用这些方法可以在比固相反应低得多的温度下得到单相的尖晶石。LiZnxNi0.5-xMn1.5O4半电池在1mol／L LiPF6／EC＋DEC＋DMC（1；1；1）中于2．8-4．9V间进行充放电测试的结果表明充放电平台仅出现在4．7V附近，因此在充放电过程中仅发生Ni^2＋→Ni^4＋的价态变化，该半电池以0．05mA／cm^2的电流密度进行充放电的首次充电比容量高达理论值并随着X值的增大而减小，测试结果还表明合成方法及热处理过程对材料的性能有决定性的影响。LiZnxNi0.5-xMn1.5O4 （0.01≤x≤0. 09） as cathode materials of lithium ion battery were synthesized by methods of coprecipitation and sol-gel. X-ray powder diffraction showed that a single spinel phase can be obtained by heating the precursor at lower temperature. Charge/discharge experiments of Li/LiZn.LiZnxNi0.5-xMn1.5O4 batteries showed that synthetic method and heattreatment process had a determined effect on the performances of the materials. Charge/discharge plateaus can be found only at a potential around 4.7V, which indicated that only Ni^2＋→Ni^4＋ transformation occured during charge/discharge process. The specific capacity of LiZnxNi0.5-xMn1.5O4 in the 1st cycle reached its theoretical value and decreased with the increasing value of x. The results of half-cell tests also showed that the cyclability of LiZnxNi0.5-xMn1.5O4 need to be improved.

关 键 词：锂离子电池 阴极材料 尖晶石 共沉淀 溶胶-凝胶 

分 类 号：O646[理学—物理化学]