A123Systems’ Hymotion L5 Plug-in Conversion Module (PCM) is a supplemental battery system that converts the Toyota Prius hybrid electric vehicle into a plug-in hybrid electric vehicle. At 10:00 a.m. Wednesday in Room W2-63 of Detroit’s Cobo Center, as part of an SAE World Congress technical session on Advanced Hybrid Vehicle Powertrains - Production Hybrid Vehicles and Hybrid Powertrain Systems Integration, researchers from A123Systems (Huang-Yee Iu) and the Idaho National Laboratory (John Smart) will present a paper summarizing the system’s field performance.
The Hymotion module is a lithium-ion battery pack with 4.0 kW·h of useable energy capacity, rechargeable via a standard 110/120V outlet. The system was designed to more than double the Prius’ fuel efficiency for 30 to 50 km (19 to 31 mi) of charge-depleting range. The Hymotion L5 PCM is the first commercially available aftermarket product complying with NHTSA impact standards.
Since 2006, when development of the product began, more than 50 initial-production Hymotion PCMs have been installed in private fleet vehicles across the U.S. and Canada. With the help of the Idaho National Laboratory, which conducts the U.S. Department of Energy’s advanced vehicle testing activity, A123Systems collected and analyzed real-time vehicle data from each fleet vehicle.
The Hymotion L5 PCM is now in full production, but the data to be presented in this morning’s presentation are only from the prototype fleet.
Data loggers were installed throughout the entire fleet to monitor vehicle parameters such as fuel consumption and vehicle speed, as well as battery parameters such as power output and temperature. From this massive amount of data three performance metrics were closely investigated: fuel consumption, electricity usage, and charge-depleting range. These metrics wer used to determine the overall performance of the Hymotion PHEV fleet.
Among the researchers findings are the following:
• After filtering only cold start warm-ups and low ambient temperature, a significant reduction in overall mean fuel consumption was experienced between charge-sustaining operation (6.46 L/100 km) and charge-depleting operation (3.44 L/100 km)
• From the coldest to hottest ambient temperatures, there was a reduction in mean fuel consumption of approximately 60%
• From the most to least aggressive driving, mean fuel consumption was reduced by approximately 80%
• As mean speed increased, there was a greater reliance on the internal-combustion engine to provide power, thereby decreasing the overall discharge energy rate and increasing charge-depleting distance.