Hybrid Vehicle Comparison Testing Using Ultracapacitor vs. Battery Energy Storage, Jeffrey Gonder

General Motors Corp. (GM) funded the National Renewable Energy Laboratory (NREL) to retrofit ultracapacitors onto a GM hybrid vehicle and compare the retrofitted vehicle?s performance to that of the production vehicle using nickel metal hydride (NiMH) batteries. The project grew out of analysis NREL performed for the United States Advanced Battery Consortium (USABC) suggesting that a hybrid vehicle can achieve significant fuel savings with a high power but low energy on-board storage system. Ultracapacitors could satisfy such a storage system description and bring potential benefits such as long cycle and calendar life, good low-temperature performance and low long-term projected costs. The platform chosen for the conversion project was the Saturn Vue belt alternator starter (BAS) hybrid, which has a 25% higher window sticker fuel economy than its conventional counterpart. The presentation will explain how the retrofit was carried out on this platform, and summarize the results of both bench-top and vehicle testing. The vehicle testing took place using the stock as well as one and two ultracapacitor module configurations, both on-road and in a climate-controlled chassis dynamometer test cell. With respect to both fuel economy and acceleration performance, the ultracapacitor HEV configuration performed at least as well as the production battery-supported HEV.

Presenter
Jeffrey D. Gonder, National Renewable Energy Laboratory