Study of the local SOC distribution in a lithium-ion battery by physical and electrochemical modeling and simulation

In this work a two-dimensional physical and electrochemical model of a lithium-ion secondary battery is presented. The transport processes and charge transfer reactions in a five layered single cell consisting of current collectors, electrode layers and separator are described by a system of partial differential equations which is solved with Comsol Multiphysics®, a modeling and simulation tool based on the finite element method. Model validation with experimental discharge characteristics of a LiNi1/3Mn1/3Co1/3O2/C6 cell at current rates of 1C to 5C was conducted and precious findings about the local state of charge of the intercalation material in dependence of its distance to the separator and the size of the active particles were made and could be explained in detail.