Thermal management

Thermal management for reliability

Long-term reliability of thermo-electrochemical energy conversion devices should be obtained prior to their market deployment. This can be possible by characterizing internal thermal conditions, identifying the sources for thermal inhomogeneity, and providing effective designs to reduce thermal stresses imposed on the devices. Our goal is to elucidate primary heat transfer pathways, estimate thermo-electrochemical non-uniformity and corresponding thermal stresses, and propose reliable designs to avoid thermal inhomogeneity while reducing performance degradation.

1. Solid oxide fuel cell (SOFC) repeating unit and stack

Among a number of fuel cell technologies, the SOFC has great potentials such as high energy conversion efficiency of 60% or higher, fuel flexibility and high reactivity. The SOFC technology has evolved significantly from cell fabrication to system installation and operations. However, performance degradation during high-temperature operations is a major barrier delaying their commercialization, which is closely related with thermal conditions inside the repeating units and stacking structure. To find out the methodology for thermal management and improve their durability, the MES lab has developed a high-fidelity 3D model for the repeating unit and stack, estimated their internal thermal conditions, evaluated thermal phenomena, and proposed new designs lowering thermal stresses. In addition, we have fabricated planar cells and assembled stacks to characterize their performance and demonstrate what we found from modeling studies.

2. Battery pack for electric vehicle

The deployment of electric vehicles to the automotive industry has raised questions about the performance and longevity of battery packs. They are vital in determining the driving range and cost of an electric vehicle. The performance and reliability of a battery pack installed in an electric vehicle is highly dependent on their thermal conditions. To enhance thermal management of battery packs and improve their reliability, the MES lab has developed a high-fidelity thermo-mechanical model for the pouch-type battery pack, examined its local thermal conditions and key heat transfer pathways, and proposed new cooling designs and control methodologies for thermal management.