FKFS Veranstaltungen

2024 Stuttgart International Symposium
on Automotive and Engine Technology

2. - 3. Juli 2024

Session: Battery | | 11:30 - 12:00

Efficient Parametrization of Electrochemical LIB Models

Christoph Lechner, AVL List GmbH

Lithium-ion batteries (LIB) play a key role in electrified mobility. Different vehicle classes, propulsion architectures and duty cycles call for tailor-made designs of the battery pack. Model-based frontloading contributes to tackling the challenges of selecting and optimizing design options early in the development phase. Electrochemical models are an established approach to model LIB. They describe the cell behavior based on balancing laws for mass and charge considering transport processes in the electrolyte and solid electrode structure. One key aspect of such models is their efficient parameterization. An advanced parametrization workflow supported by AVL CRUISE™ M is introduced which ensures data consistency and appropriate interpretation of experimental data. This is achieved by parameter classification and relating measurable quantities to relevant model parameters. The workflow minimizes the required measurement data. The major benefit of this approach is the separation of fixed parameters which describe basic properties and adjustable parameters which improve the voltage response to dynamic cell operations. Focusing on adjustable parameters enables usage of optimization tools in a next step while retaining minimal uncertainty in the full parameter set. The workflow is discussed based on selected examples of state-of-the-art cell assemblies and electrode materials. Furthermore, an outlook is given on the applicability of this workflow to next generation materials.