摘要
采用高温固相法掺入Al和Zr元素合成锂离子电池正极材料LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2,运用X射线衍射仪和扫描电镜对掺杂改性后的正极材料晶体结构和微观形貌进行表征,对电性能进行评估,探讨离子掺杂对材料结构以及电化学性能的影响。结果表明:2种元素均能很好地融入到晶格中,呈现出良好的六方晶系层状结构;在对容量影响不大的情况下,通过掺杂有效提升了材料的可逆容量,晶体稳定性得到加强,材料循环性能得以改善。在对应烧结成品中Zr占过渡金属的摩尔比为2%时,首次放电比容量为202.7 mAh/g,首次充放电效率为90.3%,1C循环50周后容量保持率为91.42%;而对应烧结成品中Al占过渡金属的摩尔比为2%时,首次放电比容量为202.2 mAh/g,首次充放电效率为90.2%,1C循环50周后容量保持率为89.78%。相比之下,掺杂Zr元素比掺杂Al元素更有优势,表现出良好的电化学性能。
High temperature solid phase method was used to prepare Al-and Zr-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode materials for li-ion batteries. The crystal structure and micro morphology of the doped cathode materials were characterized by X-ray diffraction and SEM,and the electrical performance of materials was evaluated in order to investigate effects of Al and Zr ion-doping on the crystal structure and electrochemical performance of the materials. The results show that both of two elements can be well integrated into the lattice,presenting a good hexagonal layered structure. The reversible capacity of the material is enhanced with little influence on capacity,leading to the crystal stability strengthened and cycle performance of the material improved as well. It is found that an initial discharge capacity,the initial charge-discharge efficiency and capacity retention after 50 cycles at 1C are 202.7 m Ah/g,90.3%and 91. 42%,respectively,with Zr doping ratio at 2%,but showing to be 202. 2 mAh/g,90. 2% and 89. 78%,respectively,with Al doping ratio at 2%. It is concluded that Zr doping has more advantages over Al doping and shows good electrochemical performance.
出处
《矿冶工程》
CSCD
北大核心
2017年第2期116-120,共5页
Mining and Metallurgical Engineering
基金
国家重点研发计划(2016YFB0100400)
关键词
锂离子电池
正极材料
掺杂
电化学性能
lithium-ion battery
cathode material
doping
electrochemical performance
