Design optimization of a novel negative Poisson's ratio non-module battery pack system considering crashworthiness and heat dissipation

Abstract Considering volumetric energy density (VED), crashworthiness and heat dissipation, this paper explores a novel battery pack system containing a non-module battery pack (cells to pack, CTP) and two negative Poisson's ratio (NPR) tubular structures. The CTP is designed to maximize the battery pack's VED by removing the module components and assembling the large-size battery cells into the pack. On this basis, the NPR tubular structures consisting of NPR anti-collision block and NPR radiator are installed on both sides of the CTP to meet the crashworthiness and heat dissipation requirements. In detail, the NPR anti-collision block is employed to protect the NPR-CTP system in side pole impact accident, and the NPR radiator filled with cooling water can dissipate heat with outside air. Furthermore, a many-objective optimization methodology integrating an improved radial basis function (PSO-RBF) neural network model and the third-generation nondominant sorting genetic algorithm (NSGA-III) is used to search the optimized NPR-CTP system. The results show that the initial NPR-CTP system has better crashworthiness and heat dissipation than the other CTP systems, and the comprehensive performance of the optimized NPR-CTP system has been effectively strengthened.