【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.更多还原

【Abstract】 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.更多还原