Multi‐objective optimization design of the automotive battery packs with fiber metal laminates under ground impact

Abstract Metal is commonly used due to its high absolute energy absorption (EA) value and low mass specific energy absorption (SEA_m), while carbon fiber reinforced polymer (CFRP) boasts a high mass SEA_m value but is costly. To address this, this paper suggests the application of fiber metal laminate (FML) material in automotive battery packs, as it is lightweight, with a high mass SEA_m and a moderate cost. Regarding the ground impact of a car that poses a threat to battery safety, the impact resistance of FML planes is investigated. A comparison is made among the collision responses of the battery pack enclosures made of three materials, with the same thickness and mass, showing that FML is suitable as a battery pack shell material. Furthermore, based on the kriging model and non‐dominated sorting genetic algorithm II (NSGA‐II), a multi‐objective optimization design is developed to minimize the impact displacement and mass of the battery pack enclosures with FML by optimizing the thickness of metal and fiber layers. The Pareto frontier is obtained, leading to a design modification that decreases the mass and the impact displacement compared to the initial design, as well as the improvement of the collision performance of the specific energy absorption. Highlights FML, 7075 aluminum, and CFRP were compared to validate FML's advantages. A multi‐objective optimization design for FML improves performance. Optimization values were adjusted for feasibility due to processing accuracy limits.