2009 CADILLAC ESCALADE HYBRID IS THE FIRST HYBRID IN A LARGE LUXURY SUV
06/09/2008
Cadillac
The Cadillac Escalade Hybrid is the world's first fuel-saving hybrid applied to a large luxury SUV, delivering a 50-percent fuel economy improvement in city driving. It is powered by GM's innovative, fuel-saving two-mode hybrid system and offers the same dramatic design, luxury and full-size capability that have made the Escalade an icon.
"No other manufacturer offers a hybrid than can seat eight luxuriously while simultaneously carrying or trailering lots of cargo comfortably," said Jim Taylor, Cadillac general manager. "And no hybrid delivers the dramatic presence that is synonymous with Escalade."
Escalade Hybrid is available in 2WD and 4WD configurations. It delivers up to 5,800 pounds (2,631 kg) of usable towing capacity on 2WD models and 5,600 pounds (2,540 kg) on 4WD models. Nearly all of Escalade's standard comfort and convenience features are included as standard equipment on the hybrid model, including an eight-inch, touch-screen navigation system that displays performance readouts of the two-mode hybrid system on the screen.
Escalade Hybrid extends Cadillac's leadership in the large luxury SUV category, particularly in the area of technology.
Patented two-mode hybrid technology
The Escalade's two-mode hybrid system allows it to return exceptional fuel economy in both city and highway while delivering the capabilities of a true luxury SUV. In city driving, this advanced hybrid power system enables Escalade to launch and drive low speeds on electricity alone. As additional power is demanded, the system blends output from the battery and gas engine smoothly.
GM's patented two-mode hybrid system consists of an advanced electrically variable transmission (EVT) and 300-volt nickel-metal hydride Energy Storage System (ESS). These systems work in concert with the standard 6.0L V-8 Gen IV gasoline engine with Active Fuel Management (AFM) and late-intake valve closing (LIVC) technology. AFM enables the V-8 engine to seamlessly shut off half of its cylinders when less power is needed, such as during highway cruising. This new hybrid system not only enables the Escalade Hybrid to drive low speeds on electricity alone, it also allows the 6.0L V-8 engine to operate in its more economical four-cylinder mode for longer periods.
The key to Escalade's two-mode hybrid system is that the electric power used to propel the vehicle is generated by the hybrid system itself. When the brakes are applied or the vehicle is coasting, the electric motors within the hybrid system create electricity that is stored in the 300-volt battery. This stored energy is used to move the vehicle and the regenerative braking cycle is renewed.
The two-mode hybrid system provides seamless, dependable power on demand in an efficient package. In fact, its electric motor is less than half the size of those in single-mode hybrid systems. This technology was developed and is still used in fleets of hybrid transit buses on the streets today in dozens of major North American cities. Scaled-down for use in full-size SUVs, the two-mode system delivers fuel savings where it is needed most - in large vehicles with high levels of capability. It is a core part of GM's energy diversity efforts, which are centered on reducing dependence on petroleum, improving fuel economy, reducing emissions and minimizing the automobile's impact on the environment.
Energy Storage System (ESS)
Providing power to the hybrid's electrically variable transmission's (EVT) two electric motors is a 300-volt nickel-metal hydride Energy Storage System (ESS). This battery pack is located under the second-row seat, where it takes up virtually no additional space and does not interfere with second- or third-row ingress/egress.
The primary function of the ESS is to provide power (300 volts) to the EVT and to store captured energy produced during regenerative braking. In addition to supplying power to the EVT, the ESS also provides power to the air conditioning compressor and the Accessory Power Module (APM), which converts the high-voltage supply to 42 volts for the electric power steering system, and 12 volts for the vehicle battery and other 12-volt electrical accessories.
Battery pack durability and reliability are maintained via optimized charge and discharge cycles, as well as a dedicated cooling system that draws air from the passenger compartment. As part of the vehicle's emission control system, the ESS is warranted for eight years/100,000 miles.
Regenerative braking
The Escalade Hybrid features fully blended regenerative braking to capture energy that would otherwise be lost during vehicle deceleration. By using one or both of the EVT's traction motors as a generator, braking energy is converted to electrical energy and stored in the ESS for future use to propel the vehicle.
The regenerative brakes are used along with the standard hydraulic brakes to slow the vehicle and/or bring it to a stop. Depending on the amount of braking force required, the hydraulic brakes may not even be used, such as during mild deceleration when slowing to allow space for merging traffic near a highway on-ramp.
Regenerative braking has the additional benefit of extending the life of the friction materials used in the hydraulic braking system, as well as improving braking performance in the form of shorter stopping distances.
Cadillac's smooth and quiet power
Acoustic details specific to the Hybrid model ensure it delivers the superior luxury that has been an Escalade hallmark since its inception. The details include:
A new exhaust system and resonator specially tuned for the 6.0L LIVC engine's Active Fuel Management operation. It ensures comfortable interior acoustics and a pleasant exhaust note during both V-4 and V-8 operation
An electrically driven, 300-volt air conditioning compressor reduces vibration and allows the HVAC system to cool the passenger compartment even when the gasoline engine is shut off. It includes the standard tri-zone climate system
An electrically driven, 42-volt variable-assist power steering reduces vibration and provides up to a 0.5-mpg fuel economy improvement by reducing parasitic losses common in belt-driven hydraulic systems
The Energy Storage System cooling system's internal fan is tuned to be quiet at low vehicle speeds, when the fan could more easily be heard by the occupants
6.0L V-8 engine
The Escalade Hybrid's 6.0L V-8 engine is unique. It features Active Fuel Management and late intake valve closing (Atkinson-cycle combustion process) for reduced pumping losses and better overall fuel economy. It uses flat-top pistons, cylinder heads borrowed from GM's 5.3L high-output V-8 and a 10.8:1 compression ratio, producing 332 horsepower (248 kW) at 5,100 rpm and 367 lb.-ft. of torque (498 Nm) at 4,100 rpm. It runs on regular unleaded fuel. A unique 3.42 rear axle ratio is used with this powertrain combination to help deliver the outstanding acceleration that is a hallmark of the Escalade's performance.
A key contributor to the Escalade Hybrid's fuel economy is the gasoline engine's Auto Stop mode. Once the vehicle reaches 0 mph, the gasoline engine is automatically shut down. By leaving the engine off and allowing the vehicle to move only under electric power, such as during heavy stop-and-go traffic, fuel consumption and emissions are greatly reduced.
However, when extra power is required, such as for wide-open-throttle acceleration from a standing stop, the Vortec 6.0L V-8 is seamlessly restarted so it can deliver the necessary power and torque. In this case, the engine is restarted effortlessly from the Auto Stop mode using the EVT's powerful internal electric motors; there is no traditional starter motor.
Escalade aesthetic
The Escalade Hybrid retains the qualities that have made it the leading large luxury SUV and a standard-bearer of Cadillac's overall product renaissance. It is instantly identifiable as a Cadillac and incorporates styling cues from the landmark Sixteen concept vehicle, including a detailed signature grille, front fender vent ports and layers of chrome accents.
The Escalade's warm and inviting interior features a premium layout. It is available in two colors, Ebony and Cashmere. Standard features include a distinctive instrument panel; gauges with white needles and blue light inlays with continuously lit, white-LED backlighting; Nuance leather-covered seats; leather-covered door trim and center console; and a power-assisted rear liftgate that opens and closes with the touch of a button.