LiAl二元合金体系中空位形成能的EAM计算  

EAM Calculation of Vacancy Formation Energy in LiAl Binary Alloy System

作　　者：李忠磊 张雪飞[2] LI Zhonglei;ZHANG Xuefei(Department of Materials Engineering,North China Institute of Aerospace Engineering,Hebei 065000,China;School of Mechanical Engineering,Shenyang University,Shenyang 110044,China)

机构地区：[1]北华航天工业学院材料工程学院,河北廊坊065000 [2]沈阳大学机械工程学院,辽宁沈阳110044

出　　处：《沈阳大学学报（自然科学版）》2019年第5期372-375,共4页Journal of Shenyang University：Natural Science

基　　金：河北省科技厅重点研发计划自筹项目(16211031)

摘　　要：采用嵌入原子法(embedded-atom method,EAM)计算了LiAl化合物中Li空位和Al空位在LiAl合金体系中的形成能.该计算是在该类合金系统中原子空位与其周围晶格中的原子发生了相互间的弛豫作用的条件下进行的.计算结果显示,和Al原子相比,Li原子更容易脱出晶格而失去,失去Li原子对晶格的结构、能量及稳定性影响较小,Li空位的形成会导致该类合金材料体积的缩小,这就保证了此类材料在充放电过程中负极的膨胀率更低,充放电过程中体积变化较小,不会造成电池鼓包,适合作为锂电池的负极部位,与实验的观察结果相符,为用于锂电池领域的LiAl合金体系物化性质的进一步研究及可能的潜在应用,提供了理论指导.Vacancy formation energies of Li and Al atoms in the LiAl alloy systems were calculated by the embedded-atom method(EAM).The calculation was carried out under the condition that vacancies in the alloy system would relax with atoms nearby.The calculation results show that lithium ion is more easily removed from the lattice than aluminium atom,and the loss of lithium ion has less effect on the structure,energy and stability of the lattice.The formation of lithium ion vacancies will lead to the reduction of the volume of this kind of alloy material,which ensures that the expansion rate of the negative electrode is lower in the charging and discharging process,and the volume change is smaller in the charging and discharging process.It will result in battery bulging,which is suitable for the negative electrode of lithium-ion batteries.It is consistent with the experimental results.It provides a very meaningful theoretical guidance for the further study of physicochemical properties and potential applications of LiAl alloy system in the field of lithium-ion batteries.

关 键 词：LiAl二元合金 空位形成能 嵌入原子法 弛豫 体积膨胀率 

分 类 号：TL11[核科学技术—核能科学]