Innovative vehicle battery pack design approach through multiphysics cells simulation
2022-01-0303
03/29/2022
- Event
- Content
- This paper presents the design procedure of a vehicle battery pack, in terms of electrical and mechanical requirements with an innovative methodology to model Li-ion cells’ thermo-electro-mechanical behaviour. This modelling approach can predict, through FEM analysis, if short circuit happen with consequent generation of fire in case of vehicle crash. This last aspect has several issues related to the multiphysics characteristics of the phenomena due to the fact that battery cells are made up by really thin components and, as consequence, not significant works of an entire deformable battery pack simulation have been found in literature. For this reason, the design approach studied overcomes the classical methodology in which cells’ mechanical behaviour is considered unknown to understand if cell failure appears avoiding over-engineered battery pack structure. At the beginning, a benchmarking activity on existing FEM modelling methodologies of single cells has been conducted. Subsequently, two methodologies have been compared: the layer resolved approach, in which every material composing the cell is modelled and the homogeneous approach, in which all the layers that made up the cells are modelled as they would be made up by an equivalent material. From literature, three common experimental tests on a single cell have been chosen and replicated in LS-Dyna by using the two previously models, together with data of constitutive materials and tuned to reach a good correlation accuracy between FEM and experiments. Moreover, the calibration of thermo-electro-mechanical coupling has been done by defining the short circuit occurrence parameters: an equivalent Von Mises stress has been chosen equal to a value that allows short circuit occurrences at some instants before then the experimental one to have a sort of safety factor. In the end, the battery pack designed has been verified according to two international standard tests by a complete multiphysic simulation (including thermal and electrical properties). Final evaluation has been done to consider pros and cons of this novel modelling approach and its potential application on full-vehicle simulations.
- Citation
- Messana, A., Pioli, F., Savi, M., Ferraris, A. et al., "Innovative vehicle battery pack design approach through multiphysics cells simulation," SAE Technical Paper 2022-01-0303, 2022, .