|The Provoq fuel-cell concept. Click to enlarge.|
GM CEO Rick Wagoner will use the Consumer Electronics Show in Las Vegas on Wednesday as the platform to introduce the company’s newest E-Flex concept, the Cadillac Provoq crossover. (Earlier post.) The Provoq is a fuel-cell plug-in hybrid that can drive 300 miles (483 km) on a single fill of hydrogen, with 280 miles (450 km) from hydrogen and 20 miles (32 km) from electric energy stored in a lithium-ion battery pack.
The Provoq fuel-cell concept is the fourth example of GM’s E-Flex propulsion system. Like the fuel-cell version of the Volt propulsion system unveiled in Shanghai in 2007 (earlier post), the Provoq powertrain combines GM’s new fifth-generation fuel-cell system with a lithium-ion battery.
Unlike the gasoline-engined range-extending propulsion system for the Volt (due to go into production around 2010) which is battery-dominant, the Shanghai and Provoq systems are fuel-cell centric, and use a blended operating strategy to augment their range and power with a battery pack that is roughly half the size of that in the first Volt.
Compared to the concept system unveiled in Shanghai, the Provoq fuel-cell stack offers 10% more output (88 kW vs 80 kW) and uses a larger lithium-ion battery pack (9 kWh with 60 kW peak output, compared to 8 kWh and 50 kW peak).
A pair of 10,000 psi (700 bar) composite storage tanks beneath the rear cargo floor hold 13.2 pounds (6 kg) of hydrogen to feed the fuel-cell stack, located under the hood. (The fuel-cell variant of the Volt system in Shanghai had a 4 kg hydrogen store.)
The electricity generated by the fuel cell is distributed to a 70 kW co-axial drive system for the front wheels and individual, 40 kW wheel hub motors on the rear wheels, giving the Cadillac Provoq its all-wheel-drive traction and great driving dynamics. (The Shanghai version also featured a 70 kW motor for the front wheels, but 25 kW in-wheel motors on the rear wheels.)
The Provoq’s 0-60 mph (approximately 100 km/h) speed of 8.5 seconds is a more than 30-percent improvement over the previous-generation fuel-cell system. Provoq has a top speed of 100 mph (160 km/h).
The wheels are wrapped in custom Michelin tires incorporating Green-X technology. These low-rolling resistance tires feature a tread pattern that mimics the “H20” notation for water.
Additional vehicle features include:
Solar panel integrated in the roof to help power onboard accessories, such as the interior lights, audio system and more.
Front grille louvers that close at highway speed to enhance aerodynamics, and open at low speed to provide maximum cooling to the fuel-cell stack.
A variety of recycled and recyclable materials are used, as well. Highlights include:
The headliner is wrapped in a fully recyclable soy-based material;
The carpet is made of recycled polyester and jute;
The leather used to cover the seats and instrument panel are free of harmful chemicals;
The Xorel material used on the door panels and instrument panel, treated to perform as a carbon-fiber-type material; and
The chrome trim is made with less-harmful materials.