Transport kinetics in battery electrodes

基于原位光学显微成像，研究了离子在薄膜电池电极中的输运。第一个目标是测量两种具有高应用潜力的氧化物（Li4Ti5O12, LiMn2O4）中依赖于成分和温度的体积扩散动力学。除了将扩散系数和活化能作为材料体积特性的基本量化外，还特别关注通过和沿着内部界面的传输。应发现、证明和量化间期的潜在输运障碍或沿短路路径的快速输运。界面输运系数对局部成分和温度的依赖关系应借助蒙特卡罗和动力学平均场模拟加以检验和解释。晶界的潜在影响应该通过比较不同的多晶组织来确定和量化。

Based on in-situ optical microscopic imaging, the ionic transport shall be investigated in thin film battery electrodes. The first goal is the measurement of volume diffusion kinetics in dependence on composition and temperature in two oxides with a high potential to application (Li4Ti5O12, LiMn2O4). Beside this base quantification of the diffusion coefficients and activation energies as volume properties of the materials, a particular focus is set on the transport through and along inner interfaces. Potential transport barriers at interphases or the fast transport along short cirucuit paths should be discovered, proven and and quantified. The dependence of interfacial transport coefficients on the local composition and temperature shall be checked and explained with the help of Monte-Carlo and kinetic mean field simulations. The potential effect of grain boundaries should be determined and quantified via the comparison of different polycrystalline microstructures.