作　　者： ; ; ; ;

机构地区： 中国科学院广州能源研究所

出　　处： 《新能源进展》 2017年第1期32-39,共8页

摘　　要： 采用原位模板牺牲法、溶胶凝胶法和限域共沉淀法三种不同方法分别制备了不同形貌的富锂锰基材料Li[Li_(0.2)Ni_(0.2)Mn_(0.6)]O_2(LLO)纳米颗粒。电化学测试和分析显示,使用原位模板牺牲法制备的LLO样品具有更好的比容量、循环稳定性和倍率性能,原因是:(1)制备出具有空心结构的微米球,每个空心球中的空腔能够为Li^+储存提供更多的位点,有利于提高材料的比容量;(2)空心结构的微米球具有更大的比表面积和较短的锂离子扩散路径的优点,有效提高了材料的倍率性能;(3)空心结构中的孔隙能减小体积效应对材料的影响,从而保证了结构的稳定性,提高电极材料的循环性能。 Li[Li0.2Ni0.2Mn0.6]O2(LLO)nanoparticles with diffident morphologies were prepared by the in situ templatesacrificial method,sol-gel method and confinement method,respectively.The electrochemical performance data confirmed that the product prepared by in situ template-sacrificial method had the best specific capacity,cycle stability and rate performance.The improved electrochemical performance of this product is due to the following aspects:(1)the cavity ineach hollow sphere can provide many extra active sites for the storage of Li+,which is beneficial for enhancing the specificcapacity;(2)the hollow structure made of nanoparticles often has a larger surface area and a reduced effective diffusion distance for Li+,leading to improved rate capability;(3)the void space in hollow structures may buffer against the local volume change during the lithium insertion/extraction cycling,thus facilitating the structural stability of the electrode material and improving the cyclability.

关 键 词： 锂离子电池 正极 富锂锰基材料 原位模板牺牲法

领　　域： [动力工程及工程热物理]