From the September 2016 issue
Peel back the Chevy Bolt’s androgynous design, and you’ll find a car with more than its share of electrons. In case you haven’t heard, this is a pure battery-powered electric with no combustion to drive you home when the juice runs low. But don’t fret; thanks to its ample electron supply, the Bolt offers a claimed 200-mile range. There’s also plenty of space for passengers and their stuff, and the Bolt’s attitude is highly congenial. We discovered that last item on a 50-mile drive with the Bolt’s chief engineer, Josh Tavel, riding shotgun, absorbing our barrage of questions.
Jab the accelerator, and the Bolt makes good on its name. Chevy says it reaches 60 mph in less than seven seconds, which is quicker than every other pure electric we’ve tested except the BMW i3 and the Tesla Roadster, Model S, and Model X. That said, the seats of our pants suggest that seven seconds may be conservative. Right pedal down, this front-drive hatchback tears out of the hole and scratches for traction in bends. With 266 lb-ft of torque available at just above zero rpm and multiplied seven times by reduction gears, the Bolt has no difficulty going with the flow.
In its roughly VW Beetle size, the Bolt offers ample room for passengers and stuff, as well as enough battery capacity for a claimed 200-mile range.
According to Tavel, the 200-hp motor’s output had to be trimmed at times to diminish torque steer. While passing a tractor-trailer outside GM’s Milford proving grounds, we feel exactly what he’s talking about. Those who summon all the loose electrons for acceleration will need more than a couple of pinkies on the steering wheel.
Tavel is still tweaking various calibrations since Bolt production and sales are months out, but he’s clearly proud of what his development team has achieved. This 37-year-old engineer began amateur competition at age five on BMX bikes and continued with minimal interruption to his current SCCA Spec Racer Ford campaign. A deeply ingrained racing mentality may be why Tavel hated to sacrifice any torque to diminish tugs on the steering wheel, and why the Bolt’s every motion is well managed when you toss it around. Without imposing harshness, the ride is firm to help keep body roll in check during full-boogie maneuvers. The low-rolling-resistance Michelin Energy Saver A/S 215/50R-17 tires absorb patched pavement without recoil and break away gently when tasked with a surprise lane change.
Loaded with 3600 pounds of curb weight—56 percent carried by the front tires, according to Tavel—these radials have plenty of work to do, but they feel up to the task. The electrically assisted rack-and-pinion steering is slack-free on-center, quick to respond, and nicely weighted. Walking that fine line between comfort for civilian drivers and engaging dynamics for enthusiasts is no easy feat, but Tavel deserves credit for balancing the two conflicting mentalities.
Of course, he had plenty of help making sure that GM’s latest electric-car project—following the EV1 in the 1990s, two generations of Volts, and the Spark EV—is a success. After collaborating since 2007 on OnStar communications modules, GM signed an agreement five years ago with Korea’s LG Group to design and engineer electric vehicles. Nearly as large as GM in terms of annual revenue, the Life’s Good brand is a world leader in chemicals, telecommunications, and electronics, so its expertise nicely complements GM’s metal-bending and car-marketing skills.
The Bolt is truly global in scope, with GM Korea responsible for basic car design and U.S. engineers handling development. Drawing on its electric motor and control knowledge, GM engineers designed the propulsion system. LG builds the electric motor, power-inverter module, onboard battery charger, instrument cluster, infotainment system, and the control modules that distribute electrical power, energize the accessories, and communicate with charging stations. LG also manufactures the lithium-ion battery cells in Korea and assembles them into a pack.
When GM’s president announced that the battery pack accounts for 23 percent of the Bolt’s estimated $37,500 base price (before federal tax credits), there was universal head scratching over any potential return on investment. Our guess: The value of zero-emissions credits to be reaped will exceed the inevitable per-unit losses.
The Bolt’s 200-hp permanent-magnet AC motor has a hollow center so that one half-shaft can run straight from the differential to the right-front wheel. The 960-pound heated and cooled 60-kWh battery pack holds 288 cells in a 10-cubic-foot box that doubles as the Bolt’s floor. The 3.9 x 15.3 x 0.5-inch prismatic cells are packed inside 10 modules, four of which are stacked two high under the rear seat. Five support crossmembers, cooling plates, and the pack’s steel bottom help avoid puncture by road debris. In all, the Bolt’s pack carries more than three times the energy provided in the Volt’s battery but without ruining the interior space.
According to Tavel, at least 40 miles of the Bolt’s 200-mile EPA-rated range (which we suspect is also a conservative claim) comes from regeneration, which necessitates recovering the maximum amount of energy during deceleration. Toward that end, there are four regenerative modes. The D shift-lever position stands for both drive and default. Those (like us) who prefer single-pedal electric-car driving will move the lever back a notch to the L position, significantly increasing regeneration down to zero mph. Behind the steering wheel’s left spoke, there’s a paddle to goose regen another notch higher in both the D and L positions. During our drive, the L position felt just right and comparable to the aggressive regen that Tesla provides. While the first bit of brake-pedal travel provides only regen, there’s no weird step-up in effort when the four calipers swing into action as more pressure is applied.
During the conceptual stages of the Bolt’s design and development, GM asked potential customers what sort of vehicle they’d prefer. The near-universal vote was “crossover,” which set the tone for this electric’s general configuration. Frankly, we see little crossover vehicle in the Bolt’s genes. All-wheel drive won’t be offered at launch, and that’s unlikely to change given the size and location of the battery pack. The Bolt’s length and width dimensions fit neatly between the subcompact Chevy Spark’s and the compact Sonic’s. Adding three to four additional inches of height more than makes up for the battery pack in the floor: The tall ceiling and upright seating yield 94 cubic feet of passenger space and 17 cubic feet of cargo room behind the split-folding back seat. Both those figures top the Sonic’s by a few cubic feet.
Yardsticks aside, the Bolt feels roomy, able to swallow everything short of four-by-eight building materials. Entering the front seat is a horizontal slide, with little up or down translation necessary. The rear bench is chair high with ample footroom, thanks to the flat floor, and minimal center-console intrusion. While there are three belts in back, there’s only enough width to carry that many kids. Two adults fit nicely with the center armrest deployed. Front-bucket backrests are a thin design to maximize kneeroom, and there’s a flat panel in the trunk with three-way versatility: It can be removed, mounted at an angle to segment cargo items, or placed flat over the subfloor cavity. Tavel pleaded no comment when we asked the purpose of the spare-tire-shaped well at the bottom of the cargo compartment. (In the event of a flat, tire sealant and re-inflation are your only salvation.) The obvious conclusion is that this new BEV2 platform has obligations beyond this car.
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 Electric Innards |
For any electric car, your getting-home anxiety is inversely proportional to both maximum range and battery-charging convenience. Plugging into a 120-volt outlet is convenient but ineffective for replenishing range within an average human’s life span. The better choice is the optional 240-volt AC charger fed by a 32-amp circuit at home (or work), which, according to Chevy, replenishes 25 miles of range per hour and tops off a fully depleted pack in nine hours. Another option is SAE Combo DC quick charging that adds 90 miles of range in a half-hour. Compare that with a Tesla Supercharger, also DC, which adds 210 miles of range in only 40 minutes. At the beginning of this year, there were 253 Supercharger locations sprinkled across the continental U.S. versus 387 SAE quick-charge locations concentrated on the coasts. While that sounds like a win for Chevrolet, it’s difficult to predict who will have the infrastructural upper hand when that other affordable electric, the Tesla Model 3, arrives in 18 or 24 or 36 or so months.
According to Tavel, Bolt manufacturing and deliveries are scheduled to begin before the end of this year, giving Chevy a solid start over the Model 3. Will the Bolt give Elon Musk night sweats? Or will the nearly 400,000 customers who’ve plunked down deposits for the next Tesla prove the wiser? We’ll be back when that answer is in hand.
-CarAndDriver
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