【摘要】 通过共沉淀法制备了锂离子电池正极材料锰酸镍锂(LiNi_0.5Mn_1.5O₄),研究了不同烧结温度对样品晶体结构,颗粒形貌的影响,重点对其在低放电电压条件下的电化学性能进行了研究。结果表明:不同烧结温度得到的样品都具有比较好的尖晶石晶体结构,尤其在730℃下,杂质的衍射峰强度最弱;扫描电镜图像表明不同烧结温度得到的样品粒径为100³00 nm;在不同倍率下,730℃样品放电比容量最高,其在1 C时的比容量大于锰酸镍锂理论比容量,主要原因为放电电压降低,使得更多的锂离子嵌入。更多还原

【Abstract】 The LiNi_0.5Mn_1.5O₄ used as the lithium battery cathode was prepared by the co-precipitation method. The crystal structure and the morphology for the sample sintered at different temperatures were respectively characterized by the XRD and the SEM. Especially, the electrochemical performances of the product as the lithium battery cathode under a low discharge voltage were studied. It was found that the products with spinel crystal structure were obtained at different temperatures. When calcined at 730℃, the diffraction peak of impurities in the sample was the weakest. The grain size was in the range of 100³00 nm for three samples obtained at different temperatures. According to the electrochemical test, the discharged specific capacity of the sample calcined 730 ℃ was the highest, which was more than the theoretical specific capacity of LiNi_0.5Mn_1.5O₄ due to that the lower discharged voltage can more Li-ions embedded.更多还原