Modelica-based Modeling of the Electro-Thermal Behavior Deviations within a Lithium-Ion Battery Module

Summary:

Following the increasing market relevance of stationary battery systems, the demand for simulation models as tools for optimized design and operation as well as predictive maintenance has been growing in recent years. While battery cell models for the calculation of the average electro-thermal behavior i.e. the voltage and temperature of a battery system are widely available, battery system models, which are capable of representing the distribution of the individual cells around the average values caused e.g. by capacity deviations or uneven heat dissipation are far less common.
As of now, the existing approaches for the simulation of these behavior deviations are very demanding both in computation and parameterization, which renders them inapplicable for large-scale stationary battery systems consisting of thousands of individual cells. Therefore, new modeling and parameterization approaches, which allow the simulation of the electro-thermal behavior deviations with acceptable effort, are required.
In this context, Munich University of Applied Sciences and MAN Energy Solutions collaborate on the development of a novel modeling and parameterization approach for an electro-thermal battery system model. The model is capable of representing the influences of resistance and capacity deviations and can calculate the temperature distribution within the system. The applied parameterization approach is non-destructive and less time-consuming compared to measuring the individual cells. First validation results for a commercial battery module show that the model can predict the distribution of voltage and temperature in the system with a significantly decreased effort compared to known model approaches.