2016 Chevrolet VoltEnlarge Photo
At 50 miles, the 2016 Chevrolet Volt offers the longest range of any plug-in hybrid (though the range-extended BMW i3 electric car is rated at 72 miles).
Announced this week at the Detroit Auto Show, following an October technical briefing, the technology in the new Volt may turn out to hold some secrets.
First we need to revisit November 2012, when then-product chief Mary Barra (now GM's CEO) told journalists that the company planned to focus on plug-in electric cars and mild hybrids.
"We think plug-in technology will play an increasingly important role over the years to come," she said at the time.
As we now know, Barra was previewing the thoroughly updated 2016 Volt to come--and also the Chevrolet Bolt Concept she unveiled at the show directly after the new Volt.
2016 Chevrolet VoltEnlarge Photo
GM is clearly intending to be one of the world's foremost sellers of cars that plug in, whether plug-in hybrids or battery-electric vehicles.
Offering the 50-mile Volt in the second half of this year and adding a 200-mile Bolt just two years later would be an undeniable coup.
Barra said in 2012, however, that the company would also focus on its e-Assist mild-hybrid system, which has been less than a stellar success in the market place.
Still, Barra's announcement left a crucial question unanswered: What would GM do to compete with conventional hybrids that don't plug in?
We now think that her statement that GM would concentrate on its Voltec system is the answer to that question: GM will use that drive unit, minus the plug-in hardware and the large battery pack, to offer one or more conventional hybrid vehicles.
2016 Chevrolet Volt powertrain detail - motor and power electronics unit advance briefing, Oct 2014Enlarge Photo
While sales of the aging Toyota Prius are falling, an all-new Prius will arrive for 2016--and both Ford and Hyundai plan their own dedicated hybrids as well.
We think that GM's plans to compete with those cars can be found under the hood of the new Chevy Volt.
The first Volt had one 111-kilowatt (149-horsepower) motor powering the wheels, and a separate 55-kw generator powered by its range-extending engine. It could also act as a motor to provide additional torque, though this was not widely discussed at the time.
The range-extending engine could also be clutched into the drive unit to provide supplemental torque to the traction motor under a limited set of operating circumstances, mostly at higher speeds.
The new Volt has two motor-generators, but they're now the same physical size, although with different outputs. The total drive power is again 111 kW (149 hp), with 294 lb-ft of torque.
One of the motors powers the front wheels, while the other acts as a 45-kW generator. Again, it can be used as a motor as well, providing supplemental torque to power the wheels--so that 111-kW total output now comes from the pair of motors.
GM engineers confirmed that the engine can again be clutched into the drive unit to add supplemental power as well.
The company so far has declined to provide detailed specifications of the various components. It also won't discuss the various operating modes of the system.
Those details, its engineers said, will appear in a series of papers released later this year for the Society of Automotive Engineers (SAE).