Electric vehicle battery packs operate under demanding thermal conditions, with multiple internal components generating and distributing heat unevenly. While previous research has addressed thermal modeling of individual battery cells or modules, a comprehensive framework accounting for an entire battery pack's complexity—including cable interconnects, multiple thermal pathways, and cooling systems—has been lacking until now.
Researchers have developed an integrated thermoelectric modeling approach that combines simplified electrical models of battery modules with detailed 3D finite element analysis (FEA) in COMSOL Multiphysics. The framework was validated against experimental data from air-cooled modular battery systems, demonstrating impressive accuracy with only 2.1% deviation between predicted and measured temperatures.
A critical finding emerged regarding cable connections within the battery pack: these interconnects create localized hotspots on adjacent battery modules, a phenomenon that cannot be captured by cell-only or module-only models. At full load, cable connections reached 125°C while module surfaces reached 61.6°C—temperatures that could compromise battery safety and performance if unmanaged.
The research tested multiple air-cooling configurations to mitigate these hotspots. Optimized cooling designs reduced cable temperatures from 125°C to 45°C and module surface temperatures from 61.6°C to 53.5°C at full load, while stabilizing average cell temperatures across the entire pack. This substantial improvement directly translates to extended battery life, improved safety margins, and enhanced charging capability.
For automotive engineers, this framework provides a predictive tool for battery pack thermal design optimization before expensive hardware prototyping. By accounting for realistic pack geometry, component interactions, and cooling strategies, manufacturers can better balance thermal performance against cost and weight constraints. The methodology is particularly valuable as vehicle electrification accelerates and battery power densities increase, making thermal management increasingly critical to commercial EV viability.
