项目名称: 利用高压技术研究若干锂离子电池正极材料的构效关系
项目编号: No.51302259
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 一般工业技术
项目作者: 何宇
作者单位: 中国科学院地球化学研究所
项目金额: 25万元
中文摘要: 锂离子电池正极材料的电化学性能与其电子电导和离子电导有关,而材料的晶胞参数、离子输运通道大小、配位环境等性质又决定着其电子电导和离子电导。在以往的研究中,对于这两者之间的这种构效关系认识还比较有限。引入高温高压实验手段,可以实现对材料晶胞参数及晶体结构的调制,因此,本项目将利用高温高压下原位X射线衍射,对已有的若干种锂离子电池正极材料在高温高压下的晶胞参数和晶体结构的变化进行研究,并通过原位电导测量,获得材料电子电导和离子电导随着其晶胞参数和晶体结构的变化关系。本项目还将通过第一性原理计算该种材料在高压下的晶胞参数、晶体结构、能带结构、离子输运通道、离子迁移活化能等,并与实验结果进行对比,加深对材料高温高压下性质的理解,构建相应的构效关系。该构效关系的获得,将为锂离子电池新材料的设计以及高温高压下新材料的合成提供新的思路。
中文关键词: 锂离子电池材料;构效关系;高温高压;离子输运;原位测量
英文摘要: The electron and ionic conductivity of a lithium-ion battery material affect its electrochemical performances. On the other hand, a material's electron and ionic conductivity is of great relationship with the lattice parameters, lithium-containing tunnels, and coordinated environment of the material. However, the understanding of this relationship, so called structure-function relationship, is still limited. In this project, the lattice structure evolution of several cathode materials will be analyzed by in-situ high temperature and high pressure (HTHP) X-ray diffraction method. With the utility of in-situ HTHP conductivity measurement methods, it is possible for us to compare the conductivity changes caused by the structure evolution. The first-principle calculation will be used to study the lattice structure, lattice parameters, band structure, lithium-containing tunnels and ion migration activation energy of these materials under high pressure. The comparison of simulation and experimental results will help us to establish the structure-function relationships of these materials. The design of new lithium-ion battery materials and the synthesis of the materials under HTHP can be directed by the results.
英文关键词: lithium-ion battery materials;structure-function relationship;high temperature and high pressure;ionic transportation;in-situ characterization