合金Al-Fe／C纳米复合粒子形成机制及其储锂电化学行为  

Formation mechanism and electrochemical behaviors of Al-Fe/C nanocomposite particles for lithium ion battery

作　　者：程厅 高嵩[1] 丁昂[1] 刘道林 霍凤莉 高铭 董星龙[1] CHENG Ting;GAO Song;DING Ang;LIU Dao-lin;HUO Feng-li;GAO Ming;DONG Xing-long(School of Materials Science and Engineering,Key Laboratory of Materials Modification by Laser,Ion,and Electron Beams,Dalia~ University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学材料科学与工程学院,三束材料改性教育部重点实验室,大连116024

出　　处：《中国有色金属学报》2018年第7期1361-1370,共10页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51271044,51331006)

摘　　要：以微米Al粉和Fe粉为原料,采用直流电弧等离子体气相蒸发法,在氢氩和不同CH_4含量气氛下制备了Al-Fe和Al-Fe-C纳米复合粒子。研究纳米粉体的形成机制、结构、形貌及其电化学性能,着重研究C原子的加入对纳米粒子产物的成分组成、相结构及电化学性能的影响,对各种纳米粒子形成规律及嵌/脱锂电化学机制进行了探讨。结果表明:无碳气氛下制备的Al-Fe粒子呈球状;在含碳气氛下,随着C含量的提高,粒子形貌向柱状和线状发展,粉体相组成由Al向Al_4C_3转变,合金种类由FeAl_2向Fe_2Al_5转变。当电流密度为100 mA/g时,4种复合材料电极的首次放电容量分别为348.8、193.3、275.5和628.8 mA·h/g,金属间化合物Fe_2Al_5相的形成有利于提高充/放电容量和抑制体积变化,有效提高了电极的循环稳定性能。Al-Fe and Al-Fe-C nanocomposite particles were prepared through DC arc-discharge method under a methane atmosphere with micro-sized aluminium and iron powders as the raw materials. The formation mechanism, structures, morphologies and electrochemical performances of the nanoparticles＇ samples were studied. The effects of carbon atoms on the composition, phase structure and electrochemical properties were studied, and the formation mechanism of nanoparticles as well as electrochemical intercalation/deintercalation of lithium ions were also discussed. The results indicate that the Al-Fe particles prepared in a carbon-free atmosphere are spherical in shapes, meanwhile, the carbon-containing atmosphere causes the morphology of particles columnar or linear, the composition changes from Al to AhC3 and from FeAh to Fe2Al5 in Al-Fe-C nanocomposite particles. The first discharge capacities of four kinds of nanoparticles＇ electrodes are 348.8, 193.3,275.5 and 628.8 mA.h/g, under the current density of 100 mA/g, respectively. The presence of intermetallic Fe2A15 in the powders favors to improve the capacities and restrain the volume changes during the intercalation/deintercalation of lithium ions, thus the cycle stability of electrode was greatly enhanced.

关 键 词：Al-Fe/C 纳米复合材料 锂离子电池 负极材料 直流电弧法 

分 类 号：TB34[一般工业技术—材料科学与工程]