Yu Lihong, Yang Hanxi, Ai Xinping, Cao Yuliang
Department of Chemistry, Wuhan University, China, 430072.
J Phys Chem B. 2005 Jan 27;109(3):1148-54. doi: 10.1021/jp0464369.
A nanocrystalline Li[Li(0.12)Ni(0.32)Mn(0.56)]O(2) powder was synthesized via the pyrolysis of polyacrylate salt precursors prepared by in situ polymerization of the metal salts and acrylate acid. The pyrolysis mechanism of the polymeric precursor is discussed by use of thermal analysis. Layered crystalline structure of the resulting compound was characterized by powder X-ray diffraction and high-resolution transmission electron (TEM) micrographs. The results revealed that the Li[Li(0.12)Ni(0.32)Mn(0.56)]O(2) as prepared has nanosized morphology and good crystallinity even if calcined at 900 degrees C, and the electrodes made from these nanoparticles exhibited high-rate characteristics and can deliver stable discharge capacity (163 mA.h/g) with excellent capacity retention at appropriate charge-discharge voltage interval. Since this preparation method is simple and particularly suitable for preparation of mixed metal oxides, it can be used for industrial production of highly homogeneous metal oxide cathode materials of the lithium-ion batteries.
通过金属盐与丙烯酸原位聚合制备的聚丙烯酸盐前驱体热解合成了纳米晶Li[Li(0.12)Ni(0.32)Mn(0.56)]O(2)粉末。利用热分析讨论了聚合物前驱体的热解机理。通过粉末X射线衍射和高分辨率透射电子显微镜(TEM)照片对所得化合物的层状晶体结构进行了表征。结果表明,所制备的Li[Li(0.12)Ni(0.32)Mn(0.56)]O(2)即使在900℃煅烧也具有纳米尺寸形态和良好的结晶度,由这些纳米颗粒制成的电极表现出高倍率特性,并且在合适的充放电电压区间内能够提供稳定的放电容量(163 mA·h/g)以及优异的容量保持率。由于这种制备方法简单且特别适用于混合金属氧化物的制备,因此可用于锂离子电池高度均匀的金属氧化物正极材料的工业化生产。