The Mercedes-Benz B-Class Electric Drive will not look out of place in a Mercedes showroom. It utilizes the brand’s familiar visual details, such as: a front-to-back swooshy crease in the sheet metal; prominent grille with three horizontal sections and the star emblem; and headlights that wrap around to the sides. The B-Class is well designed and attractive—although not particularly striking. Except for “Electric Drive” badging, it provides little indication of its battery-based powertrain.
That’s exactly what Mercedes wanted: an understated high-end battery-electric model that doesn’t scream about its green cred. The company is assuming that there is a market among well-heeled tech-savvy executive types that want to show discretion.
The most novel aspect of the B-Class’s design is its size and shape. It will be the smallest car available from Mercedes—a full foot shorter than the CLA luxury compact. The profile is less stylish than the CLA, and more utilitarian. Yet, Mercedes-Benz prefers to describe the B-Class as a Compact Sports Tourer, rather than a hatchback or multi-purpose vehicle.
Among cars offered with a plug, the two vehicle most similar in stature are the Ford C-Max plug-in hybrid, which is a couple inches longer and wider than the B-Class, and the Honda Fit Electric, which about a foot shorter. Both of those vehicles, like the B-Class, are hatchbacks intended to squeeze as much utility as possible out of a compact vehicle.
Of course, the electric Benz is in a much higher league when it comes to quality materials and luxury textures. The dash is not full of EV-centric graphics, but uses a relatively modest 5.8-inch color display, situated above the brand’s quintessential three large round air vents in the center.
What’s completely hidden in the B-Class is its use of a “sandwich design” under the floor. It provides a space for alternative energy sources—whether batteries, compressed gas, or hydrogen—directly beneath the seats. When offered with these non-traditional powertrains, designers lift the cabin by nearly a foot. That gives this small luxury EV a tall road position—not quite like a SUV, but with a similar sense of high perspective and visibility.
With a powertrain system that delivers a decent 177 horsepower (132 kW) and an estimated zero-to-sixty speed of 7.9 seconds, the B-Class Electric Drive is among the fastest electric cars on the market. Of course, it’s no Tesla Model S—although Tesla Motors provides the propulsion system for the B-Class.
Even though the B-Class has 70 more ponies than the Nissan LEAF, you won’t immediately notice the extra oomph in the electric Mercedes (when in the default Drive/Efficiency mode). That’s because Daimler engineers have configured the drive system for maximum comfort and control. While other carmakers—like GM with the Chevy Spark Electric, for example—unleashed as much torque as possible as a way to stand out, Mercedes confidently restrains the power to avoid snapping any heads at launch. The ride is also extremely quiet, well suited for easy city and highway cruising.
The magical power of quick electric propulsion doesn’t reveal itself until the car hits about 25 miles per hour. Yet, if you need to liven up your commute, there are two ways to unbridle the Tesla system inside this small Mercedes EV. You can reach over to the S for Sport button on the dashboard. You’ll feel an immediate difference in the pedal mapping—with much more response with a lot less foot movement.
Or, if you want to be clever, Mercedes provides a “kickdown” mechanism. Simply push your foot on the accelerator pedal just past the halfway distance to the floor, and you’ll feel a little click from the pedal. This will take the 98-kilowatt limit, and add 34 additional kilowatts.
Either way, the top speed is electronically limited to 100 miles per hour.
In terms of handling, cornering and braking, Mercedes engineers benchmarked the B-Class Electric Drive against its entire fleet. So expect the same level of refinement, responsive steering feedback, and solid road feel characteristic of the Mercedes brand. In terms of creep (how much the car slowly moves forward with nothing touching the pedals) and regen grabby-ness, you’ll also experience a drive feel familiar to Mercedes internal combustion cars.
Official EV range estimates can be misleading—whether they come from automakers or the EPA. That’s why we prefer to measure driving range of electric cars strictly by comparing the size of battery packs. Don’t worry too much about the relatively minor differences in efficiency between EVs (due mostly to size/weight of the car). It’s better to fall back on this rule-of-thumb: every kilowatt-hour of capacity yields between three and four miles of range. Drive like a maniac to get closer to three miles per kWh. Take a chill pill and you could get closer to four miles.
The B-Class Electric Drive, according to Mercedes, has a 28 kilowatt-hour battery pack. If you use (the mid-range) 3.5 miles per kWh as your basis, that means 98 miles on a full charge. The EPA provides a more conservative range estimate of 87 miles. Anyway you slice it, that beats the LEAF’s 24 kilowatt-hour pack, and the 22 kWh’s in the BMW i3.
To make things even more confusing, the B-Class EV offers a “range-plus” setting for charging. That, according to what Mercedes execs told PluginCars.com, brings the battery capacity up to 31.5 kilowatt-hours (with the push of a button before charging). The net result could be an impressive 110 miles of range. If you leave the setting to standard charging, then refueling will stop at 28 kilowatt-hours, extending the life of the battery by not charging to full capacity, but reducing the range by about 10 percent.
We need the first 100 or so B-Class drivers to report real-world reports before we know for sure, but it appears that the Mercedes electric car will have a slight edge in driving range over the competition (except, once again, for Tesla). It might be one of the few real 100-mile EVs on the market.
Mercedes provides another useful tool for maximizing rage—in the form of steering wheel paddle shifters. If you want to be a hyper-miler, you can toggle back and forth between D, D- (for more regen), and D+ (for coasting), to precisely dial in your vehicle speed and the amount of reclaimed energy. If that gets tiring, then just leave it in D-Auto—which cleverly uses radar to automatically adjusting regen level based on traffic ahead.
As stated above, the entire drivetrain system in the B-Class Electric Drive is supplied by Tesla Motors. That comes with the standard 10-kilowatt onboard charge. To take advantage of that capacity—a step up from the 6.6-kW charger on most EVs—you’ll need a sufficient supply from the grid, and a 40-amp 240-volt wall box.
At the media event we attended in early May, Mercedes mentioned that a dedicated home charger (EVSE) will be offered with the car. Further details were not available.
Many of the EVSEs on the market today have a capacity of 30 amps, so unless Mercedes comes through with a 40-amp wall unit (or you provide your own), then B-Class drivers should expect a charging rate that adds about 20 to 25 miles of range in an hour, rather than 30 miles or so from 40 amps. The difference is not huge. Besides, a full charge from empty to full—depending on all the various factors—will take four to five hours.
Even though Mercedes used Tesla’s system, access to the Tesla Supercharger network is not available. Furthermore, this generation of B-Class Electric offers no quick charge port (for using CHAdeMO or SAE Combo public quick charging). Mercedes engineers told PluginCars.com that they preferred to use the existing fuel door on the back left side of the vehicle, rather than changing the car’s sheet metal to accommodate a bigger port for faster charging. Quick charging is being considered for future model years.
Mercedes also considered—but ultimately rejected—the use of a small range-extending gasoline engine, in a desire to keep the EV system simple and compact.
The B-Class Electric Drive’s use of an “energy space” to package the EV’s battery pack allowed Mercedes to offer uncompromised passenger and cargo space. It’s a small car. Still, as stated above, it’s bigger and taller than the BMW i3 or Honda Fit—with a size and shape somewhat similar to a Ford C-Max.
Unlike the i3 (or Volt), the Mercedes EV nominally has seating for five passengers. Put two full-size human beings in the back, and the fifth passenger will have to squeeze in the middle. Three children are absolutely no problem. Slide the driver seat all the way back, and a passenger behind the driver will need to be good humored. But the purpose of this electric Benz is not long-distance highway driving. It’s comfortable commuting, and on those grounds, it provides plenty of comfort and sufficient space.
The B-Class handily beats the i3 in rear cargo space—offering 17.7 cubit feet compared to the electric BMW’s 9.18 cubic feet. With the rear seat flipped down, the B-Class provides 51.0 cubic feet of cargo space.
The Mercedes B-Class Electric Drive has not yet been rated by safety agencies. The EV is equipped standard with a radar-based collision warning system, and brake assist. The system gives the driver a visual and audible warning, and directly assists with braking if the situation requires. The list of optional features includes Blind Spot Assist, Lane Keeping Assist and Active Parking Assist.
The base price for the B-Class Electric Drive is $41,450. (The destination charge adds $925.) That’s $100 more than the BMW i3—with both German companies stacking up their small luxury electric cars directly against one another.
Navigation, LED running lights, collision warning, cruise control, active parking assist, hill-start function are standard. Mercedes offers a full line of options and interior trim packages for the B-Class EV, the same as any car it sells. The list of options and trims will become available before the car goes on sale in late summer 2014.
Battery coverage is for eight years or 100,000 miles. Like most electric cars, roadside assistance is part of the package.
Comparison of Similar Cars
Luxury car buyers who want an electric car—but not interested in the Model S’s full-size dimensions and price—can now pit two refined but affordable EVs against one another: the BMW i3 and the Mercedes B-Class Electric Drive. Well-heeled buyers who previously accepted the relatively humdrum interior quality provided by Japanese or American models can step back up to German tastes.
Judging from our time behind the wheel of the B-Class and i3, both cars will equally deliver the high level of handling and comfort expected from a BMW or Mercedes. Buyers will need to consider two main factors that separate the two choices: styling and the availability of a range-extending gas engine.
The BMW i3’s iconoclastic visual design, and barn door treatment, might be a hit or it could prove to be just too weird and geeky. However, one of BMW’s innovations—the availability of a range-extending gas engine that essentially doubles driving range and allows for quick refueling—could compensate for any stylistic misgivings, even as it adds about $4,000 to the cost.
Mercedes, like a lot of other car companies, likes to use the “no compromise” message in its marketing. Given the B-Class’s five seats—compared to the i3’s four spots—and its generally more accessible and versatile platform, the Mercedes EV has legitimate advantages. But 85 miles (or possibly close to 100 miles) of range expected from the B-Class Electric Drive has to work for your commute. The i3 with the range-extender, while adding some level of internal combustion, removes those range concerns.
“BMW is a formidable competitor,” said Mark Webster, Daimler’s manager of e-mobility, in an interview with PluginCars.com. “They’ve put a lot of energy and resources behind the car. I want them to do okay, but not super well.” He said that the B-Class is a “very versatile car with four real doors and five real seats.”
The i3 sacrificed some creature comforts like power seats and has thin tires, all in an effort to lower weight and boost efficiency. Webster calls these moves, and the i3’s arguably disjointed looks “a modern interpretation of an electric car.” He said, on the other hand, the B-Class is “more of a proven platform, and we have proven partner in Tesla.”
The B-Class EV will be available in late summer 2014 at select dealerships in California, Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Rhode Island and Vermont. Fifty-state availability is expected as early as 2015.
Mercedes does not currently offer a dedicated website for pre-ordering. We suggest visiting your local Mercedes dealership to express your interest.