Ensuring uniform coolant distribution in electric buses is crucial for battery
performance, longevity, and thermal stability. This study optimizes the battery
thermal management system (BTMS) for an 18-m electric bus, addressing uneven
coolant flow to battery packs caused by pressure drop variations.
One-dimensional (1D) simulations were chosen for their ability to quickly and
efficiently analyze flow and pressure variations, providing a fast solution to
optimize coolant distribution across the system.
dP-Q curves for the BTMS pump and battery packs were integrated into the 1D model
based on supplier data, while the flow resistances of other components (pipes,
bends) were calculated using KULI software. To correct flow imbalances, pipe
diameters were adjusted to increase resistance in over-cooled areas,
redistributing coolant to under-cooled sections. This modification resulted in a
balanced flow and improved thermal consistency, contributing to longer battery
life. Validation showed an 11% deviation between experimental and simulation
results, confirming the system’s reliability.
This study emphasizes the importance of precise flow management for enhancing
battery life and provides a scalable solution for optimizing the thermal
management of electric vehicles.