General Motors is making the Chevrolet Volt its top priority at this point, but there are now rumors circulating that Cadillac may be the next GM brand to get its own vehicle using the Volt’s technology. Motor Authority reports that a Cadillac Volt would make great economic sense because the luxury appeal of a Cadillac means consumers would be more willing to pay out for the expensive technology found in the Volt.GM’s Bob Lutz has stated that an electric-powered Cadillac was definitely a possibility and that the brand would unveil “some kind of dramatic environmental statement” soon.
The Chevrolet Volt is a plug-in series hybrid vehicle to be produced by General Motors, expected to be launched as a 2011 model with production currently slated to begin in 2010. The Volt’s propulsion system will be based on GM’s new E-Flex platform. Since the current Society of Automotive Engineers (SAE) definition of a hybrid vehicle states the vehicle shall have “two or more energy storage systems both of which must provide propulsion power, either together or independently”, the company has avoided the use of the term “hybrid” when describing its non-conforming E-Flex designs. Instead GM has described the Volt as an electric vehicle equipped with a “range extending” gasoline powered internal combustion engine (ICE) as a genset and therefore dubbed an “Extended Range Electric Vehicle” or EREV.
However, the combination of an internal combustion engine and electric motors in such a configuration is most often referred to as a series hybrid. Unlike current commercially available hybrids, the actual propulsion of the Volt is accomplished by the electric motor, as the internal combustion engine (ICE) is not mechanically connected to the wheels. With fully charged batteries, this electric power will initially be sourced exclusively from its on-board Lithium Ion batteries for up to 40 miles (64 km), a distance capable of satisfying the daily commute of 75% of Americans, which averages around 33 miles (53 km). After 40 miles (64 km), the range of the Volt will need to be extended through the use of a small 4-cylinder ICE which drives a 53 kW generator.
The Volt concept vehicle has four doors with a rear liftgate, and is capable of carrying four passengers. On September 16, 2008 General Motors first publicly displayed the production design model of the Chevrolet Volt that differed greatly in design from the original concept car.
For trips less than about 40 miles (64 km) per charging cycle, the Volt will not use any onboard gas, so assigning a fuel consumption value which only referred to onboard fuel might not be appropriate. Once the Volt’s battery has discharged to its lower limit set-point, the Volt’s range-extending gasoline engine is expected to get from approximately 50 mpg-US (4.7 L/100 km; 60 mpg-imp) to as much as 150 mpg-US (1.6 L/100 km; 180 mpg-imp) depending on its run-time duty cycles. This is because once the battery has been recharged to an upper limit set-point (by the engine driven 53 kW onboard generator), the internal combustion engine will again shut off.
The anticipated energy capacity of the Volt’s 375 lb (170 kg) 220-cell Lithium Ion battery pack is estimated at 16 kWh, but is only charged to 85% full when charged up, and is discharged to 30% SoC approximately, before the engine cuts in and maintains the charge at around this level. When the vehicle is plugged into a charger the battery SoC is restored to 85%. Hence the battery has an effective capacity in use of 8.8 kWh. An electric car’s range is about 4 to 6 miles for each kWh of electric energy and the VOLT is expected to get about 5 miles per kWh. If the Volt were equipped with 500 lbs of Nickel Metal Hydride batteries, yielding 13 kWh of energy, all of which is accessible for an indicated range of 65 miles on a charge.
In the U.S. market, the price of the Volt is expected to be around US$40K with government approved subsidies bringing the price to around $32.5K. Initially, the GM vice president wanted it at about US$30K. The indicated price for the UK market is GBP£20K.