The world’s best-selling plug-in hybrid vehicle has been re-engineered from a clean sheet, on a new vehicle architecture, giving the 2016 Chevrolet Volt 30% greater electric vehicle (EV) range—estimated 50 mi (80 km) total on the battery alone—and more than 100 mi (160 km) additional range using both the new 18.4 kW·h battery and the equally new 1.5-L range-extending gasoline internal combustion engine (ICE).
General Motors engineers estimate the new Volt can travel 420 mi (675 km) using its full battery state of charge and the contents of its 8.9-gal (33.7-L) gasoline tank. Fuel economy is expected to be 41 mpg combined and 102 mpg-e when EPA testing concludes. Given that Volt owners overwhelmingly charge their cars at least twice a day during typical operation, engineers reckon the new vehicle should deliver an average of 1000 mi (1610 km) of driving per each tank of gasoline.
Drops nearly two EPA weight classes
“Range was the most-requested improvement our customer base of over 73,000 owners asked for in the new Volt,” explained the car’s Executive Chief Engineer (and veteran of the original Volt program), Pam Fletcher. “This is GM’s most studied group of owners, even more than Corvette. We used the OnStar feature in collecting user data and found they also wanted more ‘fun-to-drive’—and they wanted a good-looking rather than quirky exterior.”
The Volt development team, with the full support of GM top management in this key program, delivered those customer wants and more. As the photo at the top of this article shows, the Gen-2 Volt “isn’t a funny-looking/cute car anymore,” observed John Cafaro, Executive Director of Chevrolet’s global design office. It’s now got the handsome (to the author’s eyes) “projectile look” front end, now with active aero shutters in the grill, that’s become a strong styling cue across the Chevy range—not surprising since the Cafaro-led team that penned the Impala also designed the new Volt.
Along with the greater driving range comes a claimed 19% percent improvement in EV mode acceleration from zero to 30 mph (48 km/h), in 2.6 s, and a 7% improvement from zero to 60 mph (97 km/h), in 8.4 s. Some of this performance boost is due to significant mass-reduction actions. Overall, the 2016 Volt drops nearly two EPA weight classes [a class is 125 lb (57 kg)]—a feat that’s nearly unheard of in most new vehicles where simply achieving mass parity from one generation to the next is considered a win. The new Volt is in the 3875-lb (1757-kg) weight class.
“Well, admittedly the first-gen car was a bit overdesigned, making it a bit overweight, but we were counting ounces on every [second-gen] component,” said Andrew Farah, the Chief Engineer on both new and old Volts.
The switch to GM’s new more mass-efficient Gen-2 Delta platform (Volt is the first application) with its high percentage of high-strength steel alloys helped the cause, as did switching to aluminum hood, liftgate, and cylinder block. The new Voltec drive unit sheds 100 lb (45 kg) versus its predecessor, and the new battery pack of 360-V nominal/400-V peak voltage is about 21 lb (9.8 kg) lighter, too. The new Volt also benefits from futher aerodynamic improvements in the upper- and under-body areas.
Back-seat passengers may appreciate that the seat now accommodates three persons, though to get into the additional perch still requires being smallish in dimension and scaling the rather tall center tunnel under which the large T-shaped lithium-ion battery pack resides. The pack itself features revised Li-ion cell chemistry; the cells remain a pouch-type form factor and are still supplied by LG Chem from its Holland, MI, plant.
The car’s two-motor Voltec drive system operates both motors together in more driving situations in both EV and extended-range operation. The ability to use both motors contributes to the car’s improved acceleration performance, Farah said. For a comprehensive look at the Gen-2 Volt propulsion system and battery published by Automotive Engineering last October, go to: http://articles.sae.org/13666/
Charging improvements
Current Volt owners provided a wealth of data that helped the development team improve the new Volt’s charging system and charging experience. Owners now can set their charging preferences exclusively for “home” charging, and the vehicle will automatically adjust to that setting when it is at “home” based on GPS data,” explained Farah. More than half of Volt owners charge on 110 V, Fletcher noted, and the car is equipped with an SAE J1772 "combo connector," so Level 3 capability wasn’t in the product plan for 2016, she said.
Owners can pre-set their Level 1 (120 V) charging level at 8 or 12 A and can charge immediately, set a departure time for each day of the week, or set a departure time and a utility rate schedule to charge only at off-peak rates. These settings only have to be programmed once and the Volt will default to them when the vehicle returns to its home location.
There’s also a new charging-status system that features a specially designed tone that indicates when charging has begun, with additional tones for delayed charging. It will also indicate if the charge port door on the left front fender was left open after the last unplugging.
A new 120-V portable cord set has a simpler, more compact design and its storage bin was relocated to the left side of the Volt’s rear cargo area, above the load floor, for improved accessibility.
The Volt’s standard and available safety systems suite features a standard rear-vision camera, 10 standard air bags, and available lane keep assist with lane departure warning; side blind zone alert with lane change alert; rear cross traffic alert; forward collision alert with following distance indicator; front automatic braking, and advanced park assist with front and rear park assist (semi-automatic parallel parking). The rear parking brake is a new “motor-on-caliper” design, Farah said.
Start of production is slated for early 3Q15 at GM’s Hamtramck, MI, assembly plant. The Volt’s battery pack is built at GM’s Brownstown, MI, plant. The new Voltec drive unit is manufactured at GM’s Warren, MI, Powertrain plant. The 1.5-L engine will be manufactured at GM’s Toluca, Mexico, engine plant for the first year of production, then shift to the Flint, MI, engine plant. Approximately 70% of the car’s content is U.S. and Canadian built, a nearly 20% increase from the first-gen car.
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