A key part of the EcoCAR 2 learning experience is designing the main traction battery. Competition-level sponsor A123 Systems provided each team with a battery system, so the University of Waterloo Alternative Fuels Team (UWAFT) needed to prove that its battery design was safe and robust. One of the key elements of the battery design is thermal performance. UWAFT quickly realized that good thermal performance will be critical to harnessing every joule and kW from the main traction battery. A cooler battery allows for more power and a longer lifetime.
UWAFT turned to Dana-Long Manufacturing to provide cold-plates that would extract heat from the modules. The cold-plates feed water through themselves, providing a cooling surface for the batteries. These plates are custom-made for UWAFT and the A123 module geometry. Before the plates could be used, however, the team needed to analyze whether they could perform under the most extreme conditions: A hot summer day in Yuma, Arizona – where the team expects to test its design in Year Two of EcoCAR 2 finals.
Competition level sponsor CD-Adapco’s Star-CCM+ was deployed to analyze the performance of the cold-plates. Star-CCM+ is a computational fluid dynamics (CFD) package that can simulate fluid flow and heat transfer. By leveraging Star-CCM+, UWAFT avoided using an expensive and complex thermal test bench. Parameters such as flow rate could also be changed quickly and the results compared easily. CD-Adapco staff also provided invaluable training and advice that helped the team set-up the cold-plate simulation. The team is confident in its design and is ready to test it out in the heat of Yuma next year!