螯合剂量和锂锰比对尖晶石LiMn_2O_4性能的影响  

Effect of Chelator Content and Li/Mn Ratio on Properties of Spinel LiMn_2O_4

作　　者：蔡羽[1] 朱金娥[2] 李董轩[2] 赵胜利[2] 

机构地区：[1]河南科技大学信息管理研究所,河南洛阳471003 [2]河南科技大学材料学院,河南洛阳471003

出　　处：《热加工工艺》2009年第16期59-61,109,共4页Hot Working Technology

基　　金：国家自然科学基金项目(20504026);河南科技大学科研基金项目(2007zy002)

摘　　要：考察了螯合剂量和Li与Mn的摩尔比对尖晶石LiMn2O4结构和电化学性能的影响。结果表明:直接以PAA为螯合剂,以LiNO3和Mn(NO3)2为锂源和锰源,采用溶胶-凝胶技术合成了无杂相、分散性好、尖晶石结构完整的LiMn2O4粉体。前驱体干凝胶在烧结450℃时开始逐步形成尖晶石LiMn2O4结构。随着PAA量减少,尖晶石结构峰越来越明显;当Li与Mn的摩尔比为1.06:2,且PAA与总金属离子摩尔比为0.3:1时,PAA燃烧所放出的热量,既能满足结晶所需要的热量,又可避免杂相Mn2O3的出现;在电流密度0.1mA/cm2,截止电压3.5～4.3V测试条件下,该材料循环性能稳定,有望成为高性能锂离子电池正极材料。The effect of chelator content and Li/Mn molar ratio on the structure and electrochemical performance of spinel LiMn2O4 was investigated. The results show that the spinel LiMn2O4 powder with purity phase, well dispersivity and complete structure is prepared using PAA as chelator and the LiNO3 and Mn（NO3）2 as the source of Lithium and manganese. The gel precursor gradually forms the spinel LiMn：O4 powder from 450 ℃ during the sintering. The spinel structure becomes better with the decrease of the PAA content. When the molar ratio of Li/Mn is 1.06：2 and the ratio of PAA to the total metal ions is 0.3：1, the combustion heat of PAA can not only supply the demand of crystallization behavior but also avoid too much Mn203. At the current density of 0.1m A/cm^2 and cut-off voltage of 3.5 ～4.3V, LiMn2O4 powder possesses well cycle performance. So it is hopeful to be the cathode material for high-energy lithium-ion battery.

关 键 词：溶胶-凝胶 LIMN2O4 螯合剂 结构 电化学性能 

分 类 号：TB321[一般工业技术—材料科学与工程]