A rapid multiphysics framework for predicting thermal runaway propagation in lithium-ion battery packs

초록

This study proposes a computationally efficient multiphysics framework to estimate thermal runaway propagation (TRP) of a lithium-ion battery (LIB) pack. The proposed framework addresses the academic challenges associated with experimental and conventional models which lack practicality in costs and computational burden by providing a design-enabling tool for TRP of LIB packs. The proposed framework integrates thermal and exothermic reactions and pressure sub-models with a novel acceleration strategy in that the proposed framework aims to provide a design-enabling solution for securing the safety and reliability of LIB packs. Specifically, the proposed framework calculates heat generation by simplifying the exothermic kinetics inside an LIB, thereby reducing the number of governing partial differential equations. The three-dimensional profile of the spatially distributed heat generation is also transformed into an equivalent lumped heat representative, resulting in speeds up to 500 times faster than that of conventional finite element methods. Notably, the proposed framework maintains total heat generation accuracy within 5%, suggesting that the proposed framework ensures both speed and accuracy when estimating TRP of an LIB pack deployed in electric vehicles. Physics-informed parameter estimation enables generality across various cathode chemistries and cell geometries. Extensive experimental validation using various module geometries (prismatic and cylindrical) and cathode chemistry confirms the accuracy, robustness, and applicability of the proposed framework. Consequently, the proposed framework offers a design-enabling solution for LIB packs by providing a robust and generalizable parameter set, which enhances the safety and reliability of LIB systems for practical applications during the design phase.

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