合成条件对尖晶石型Li_xMn_2O_4正极材料结构的影响

Effects of Synthetic Technology on the Structure of the Spinel Li_xMn_2O_4 Cathode Material

采用X-射线衍射(XRD)、扫描电子显微分析(SEM)等方法研究了不同温度、原料配比等工艺因素对LixMn2O4正极材料的微观形貌、物相结构等影响.结果表明:LiMn2O4样品的晶格常数、晶胞体积和晶粒大小随着合成温度的增加而增大,当合成温度超过700℃时,样品由尖晶石型LiMn2O4单相组成,在750℃下可合成粒度分布均匀,晶体结构完整的LiMn2O4.当x<1时,LixMn2O4样品的颗粒呈不规则形状,当x>1时,样品的形状为球形颗粒;LixMn2O4样品的晶胞常数和晶胞体积随着x值的增加而呈现出先增后减的规律.

The effects of Synthetic technology such as temperature, the ratio of raw material on the micrograph and phase structure of the LixMn2O4 cathode material were investigated by X-ray diffraction （XRD） and scanning electron microscope（ SEM ）. Results show that, the crystal lattice parameter, cell volume and grain size of the LiMn2O4 increase with increasing temperature. The sample is composed of single-phase spinel LiMn2O4 when the synthetic temperature is over 700℃. LiMn2O4 with uniformity of size and integrality of microstructure is obtained at 750℃. The particles of the LixMn2O4 specimen are abnormity and spheroid when x〈1 and x〉1, respectively. The lattice parameter and cell volume of the Li, Mn2O4 sample increase and then decrease with increasing the x value in the sample. 6figs.,2tabs., 14refs.