Microscopy imaging based numerical model of Li-ion batteries electrode: A parametric study through a design of experiment approach

[摘要] The aim of this study is to probe the influence of different transport and insertion kinetics parameters on battery performances through their impact at the electrode's microstructure level using numerical simulations. To that end, a multi-physics model of a Li-ion battery electrode is developed based on microscopy image reconstruction. A design of experiment (DOE) approach is used to determine the effects of the five selected parameters in a reduced number of simulations. Each combination is a test point for which a galvanostatic discharge at 2C is simulated. A statistical analysis of the parameters influences shows the predominance of the interfacial insertion kinetics on the discharge capacity followed by the lithium liquid and solid diffusions. The effects of the parameters are also analyzed at microstructural level. It is observed that under liquid diffusion limitation, particles lithiation decreases with the distance toward the separator. Meanwhile, solid diffusion limitation leads to particles lithiation depending only on their developed surfaces. For the first time, a statistical analysis on parameters influence on particles lithiation heterogeneities is also presented. The potential use of this approach in prospects as a means to optimize available capacity while reducing lithiation heterogeneities is tackled at the end of this paper.

[发布日期] 2021-09-30

[关键词] Li-ion batteries;Numerical modeling;Microstructure;Microscopy imaging;Design of experiment;Lithium transport;Lithiation heterogeneities