镍锰过渡金属氧化物梯度材料的合成及性质研究

发布时间：2019-05-18 08:52

【摘要】：层状LiMO_2(M=镍、锰、钴)兼具高比容量和高工作电压,因而成为是最有发展前景的正极材料之一。本论文利用共沉淀方法研究制备镍锰正极材料。通过XRD、SEM、EDS、恒电流充放电测试、EIS以及CV等探究所合成的样品的晶体结构、形貌以及性能。所有合成的无钴/低钴型镍锰氧化物的衍射峰均属于六方晶系,α-NaFeO_2的层状结构,为R-3m空间点群。(006)/(102)和(018)/(110)两峰的高度分裂表明一个有序的六角分层结构。前驱体形貌为层状,分层结构会抑制正极和电解质之间的副反应,提高Li~+扩散速度。因此,样品有良好的Li~+导电性和较小的Rct,提高电池的容量以及性能。结果表明,改变样品物料比、滴加速率、升温速率等条件,能稳定样品结构,改善其电化学性能。
[Abstract]:Layered LiMO_2 (M = nickel, manganese, cobalt) has become one of the most promising cathode materials because of its high specific capacity and high working voltage. In this paper, nickel-manganese cathode materials were prepared by coprecipitation method. The crystal structure, morphology and properties of the samples synthesized by XRD,SEM,EDS, constant current charge-discharge test, EIS and CV were investigated. All the diffraction peaks of cobalt-free / low cobalt Ni-mn oxides belong to hexagonal system and 伪-NaFeO_2 layered structure. It is a R 鈮，

本文编号：2479862