Dimension-performance integrated assembly analysis method considering battery module’s post-welding rebound mechanism

Abstract

Dimensional deviations in battery module length can stem from the internal forces release after the assembly process. This manuscript presents the Dimension-Performance Integrated Assembly Analysis Method, which considers both post-assembly dimensional distributions and post-service residual life. The modified Hill strain energy function is employed to characterize the hyperelastic mechanical behavior of the aerogel-based thermal insulation pads, alongside establishing a process-based model for the battery module's post-welding rebound. Furthermore, an equivalent model is introduced to compute the equilibrium positions of the compression and tension curves to ensure both precision and efficiency. The dimensional measurements validate the accuracy of the process-based model and the equivalent model, and a thorough analysis of the module's rebound mechanism sheds light on the interplay between the equivalent model parameters and the structure mechanical properties or initial dimensions. Accounting for the battery module's post-welding rebound mechanism, the Dimension-Performance Integrated Assembly Analysis Method assesses the impact of key dimensions and process parameters on target dimensional distributions and structural failure probability. This method enables the design of battery thickness tolerance band and process parameter ranges to ensure zero failure probability within the target charge-discharge cycles.