As the deadline to ship their EcoCAR (the VT-REX) out for EPA testing creeps closer, the Hybrid Electric Vehicle Team at Virginia Tech (HEVT) is working hard to make significant changes to its vehicle. Last week, the team focused on making improvements to the 360 Volt, A123 Lithium Ion Phosphate battery pack. While incorporating the battery, HEVT has been challenged to maintain adequate cargo space and eliminate a large gap between the floor pan and the battery base plate, but these issues have been addressed in the latest round of improvements.
For starters, HEVT lowered the battery using a new layout that contains all battery modules within the frame rails of the car. This adjustment helps open up more space in the trunk and lowers the center of gravity in the rear, which helps alleviate over-steer. In addition, the passenger compartment is now completely sealed from outside elements including carbon monoxide, road debris, and noise.
Changes to the battery, including a redesign of the high voltage battery pack, are largely motivated by the installation of a more powerful rear traction motor. HEVT engineers dedicated the majority of the week to rewiring the low voltage communication harness as well as the high voltage wires in order to accommodate the new battery module layout.
To complete the battery upgrades, HEVT needs to finalize the wiring, permanently mount the modules to the base plate, and finally secure the top of the battery case. The team is confident that these modifications will ensure the VT-REX is a highly efficient and “green” vehicle by improving its electric capabilities.
Check out the video below to watch HEVT updating its EcoCAR battery!