The continuously increasing demand for Battery Electric Vehicles, together with the customer requirement for higher ranges poses new challenges on the battery pack design. Drawing inspiration from aerospace design principles, wherein fuel tanks are integrated structurally into airframes to save weight and increase efficiency, structural battery packs are also experiencing growing use in the automotive field. In fact, when a structural battery pack is considered, significant weight savings can be achieved, potentially extending the vehicle range. Additionally, this weight saving could be further exploited to increase the battery pack size with respect to a non-structural battery pack, further enhancing the vehicle range without adding extra weight.
To address the complexity of integrating structural battery packs, Finite Element simulations are typically adopted to evaluate battery pack integrity and estimate its contribution to the structural behaviour of the overall vehicle. However, the detailed modelling of large number of cells and their interactions with components like cell carriers, busbars, and plates is computationally intensive. To overcome this limit, this contribution proposes a methodology to derive a simplified model of the cells module, deriving an equivalent homogeneous orthotropic material.
The results of this simplified approach have been compared to the results obtained from a complete model considering all the individual cells and all related components. The reduced computational effort resulting from the proposed methodology makes it suitable for integration into a more complex full vehicle model. This enables an optimization of the overall design, leading to possible significant improvements in vehicle performance, range and costs.