硅掺杂锰酸锂的自蔓延燃烧制备及其性能研究  

Study on preparation and properties of silicon doped lithium manganate by self⁃propagating combustion

作　　者：朱志红 朱永芳 ZHU Zhihong;ZHU Yongfang(School of food and drug,Luoyang Polytechnic,Luoyang 471000,China;College of Petrochemical Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]洛阳职业技术学院食品与药品学院,河南洛阳471000 [2]兰州理工大学石油化工学院,甘肃兰州730050

出　　处：《无机盐工业》2023年第5期66-70,共5页Inorganic Chemicals Industry

摘　　要：为了解决充放电过程中锰酸锂循环性能较差的问题,采用自蔓延燃烧法制备了硅掺杂锰酸锂超细颗粒(LiMn_(1.95)Si_(0.05)O_(4),简称LMSO)。通过X射线衍射光谱、扫描电子显微镜、循环伏安法等方法研究了硅掺杂对锰酸锂晶体结构、微观形貌和电化学性能的影响。结果表明,硅掺杂不会改变锰酸锂尖晶石的结构;锰酸锂的粒径大于0.1μm,而大部分硅掺杂锰酸锂颗粒小于0.1μm。颗粒尺寸减小,缩短了锂离子的扩散路径,提高了材料的电化学性能。LMSO在0.2C倍率下放电比容量高达123.7 mA·h/g,在1C倍率下循环100次后的容量保持率为95%。In order to solve the problem of poor cycle performance of LiMn2O4 during charge⁃discharge cycles,silicon doped lithium manganate ultrafine particles(LiMn_(1.95)Si_(0.05)O_(4),referred to as LMSO)were prepared by self⁃propagating combustion method.The effects of silicon doping on the crystal structure,morphology and electrochemical properties of lithium manga⁃nate were studied by means of X-ray diffraction,scanning electron microscopy and cyclic voltammetry.The results showed that silicon doping did not change the structure of lithium manganate spinel.The particle size of lithium manganate was greater than 0.1μm.Most silicon doped lithium manganate particles were less than 0.1μm.The reduced particle size short⁃ened the diffusion path of Li+and improved the electrochemical properties.At 0.2C rate,the specific discharge capacity of LiMn1.95Si0.05O4 was as high as 123.7 mA·h/g.After 100 cycles at 1C rate,the capacity retention rate was 95%.

关 键 词：自蔓延燃烧 锰酸锂 正极材料 锂离子电池 

分 类 号：TQ152[化学工程—电化学工业]