Li-ion batteries are widely being used for various applications and serve as the solution for the storage of renewable energy sources. These LIBs are superior to conventional primary batteries for various reasons, including high volumetric and gravimetric densities. However, it is well known that the performance and longevity of the batteries are affected due to the stress-diffusion interactions in the various shaped active particles, which chiefly constitute the microstructure of the electrodes of the batteries. A sequential numerical framework is developed to analyse the electrode microstructure of circular-shaped active particles. We have employed numerical tools viz., the Finite Element Method (FEM) and the Discrete Element Method (DEM) to analyse the microstructure undergoing the potentiostatic charge and discharge.
For the first part of the talk, based on the aforementioned framework, a parametric study is carried out on the microstructures of the graphite electrode. The mono and poly-sized assemblies of active particles with varying packing fractions are considered for the study. The potentiostatic charge and discharge studies are carried out on these assemblies. The effect of the increased partial molar volume of the active particles is studied on the assemblies. The results of the carried out microstructural studies will be discussed.
For the second part of the talk, analytical work has been carried out to study the mechanics of contacting ellipsoidal shaped particles under the influence of potentiostatic and galvanostatic charging. A detailed study has been conducted considering the different aspect ratios, size ratios of the particles, maximum stoichiometric concentration and collector stiffness. The results pertaining to this will also be presented.