GM Sequel Powered by Next-Generation Fuel Cell System

January 10, 2005 by Jeff Shepard

General Motors Corp. (GM, Detroit, MI) unveiled its new Sequel fuel cell vehicle, which features a 25% more powerful fuel cell stack that helps the Sequel achieve a 300-mile range and 0 mph to 60 mph acceleration in less than 10 seconds, while emitting only water vapor.

The fuel cell power module consists of the actual fuel cell stack, the hydrogen and air processing subsystems, the cooling system, and the high-voltage distribution system. The power module delivers 73 kW of high-voltage power for the electric traction motors, as well as auxiliaries like heating, ventilation and air conditioning, by-wire electronics and the battery.

Hydrogen introduced into the fuel cell is directly converted to electric power to drive torque control of all wheels. A high-voltage, lithium-ion battery system provides extra power to the three electric motors during acceleration. It also stores power regenerated during braking to help extend the vehicle's overall mileage range. The fuel cell propulsion system is integrated into the vehicle package; the drive motor development is linked with the rest of the system, increasing overall efficiency and improving performance.

Sequel's 300-mile range is made possible by advances in high-pressure storage that enable the vehicle to carry 8 kg of hydrogen, more than double that of GM's HydroGen3 fuel cell vehicle. Three lightweight, carbon composite tanks store hydrogen at 10,000 psi (700 bars), compared to 5,000 psi (350 bars) in the Hy-wire, Sequel's predecessor. The larger tanks also enable a better ratio of stored hydrogen mass versus fuel storage system mass.