Volkswagen of America, Inc. announced today details of the e-Golf, its first fully electric vehicle, and scheduled to go on sale in select U.S. states in the fourth quarter of 2014.
The 2015 e-Golf will debut at the Los Angeles Auto Show and is part of Volkswagen’s Think Blue approach to sustainability. Through this approach, Volkswagen has stated that it aims to be the world leader in e-mobility among automakers by 2018.
Although Volkswagen has sold more than 30 million Golf models worldwide, this is the first zero tailpipe emissions, fully electric version of the car that will be sold to the public.
The e-Golf will be available in five-door form only and will be recognizable by its unique aluminum-alloy wheels and by its LED headlights, the first time they have been used as standard on a Volkswagen vehicle.
Volkswagen said the LED headlights are more energy-efficient than Bi-Xenon systems, yet produce even more light. The standard LED daytime running lights are also highly energy-efficient and have a signature C-shaped design, a feature of Volkswagen’s electric vehicles.
The e-Golf will be powered by a 115-horsepower electric motor; the EEM-85 synchronous permanent-magnet AC motor develops 199 pound-feet of torque, allowing the e-Golf to reach 25 mph from rest in 4.2 seconds and 60 mph in approximately 10.4 seconds. Top speed will be electronically limited to 87 mph.
VW explained the 12,000-rpm motor and the single-speed EQ270 transmission form a compact unit; meanwhile, the EQ270 also incorporates an integrated differential and an electro-mechanical parking brake. The motor and transmission was developed in-house and is made at Volkswagen’s components plant in Kassel, Germany.
VW estimates the average range for the e-Golf is between 70 and 90 miles, depending of course on driving style and charging behavior. Helping ensure optimal range in cold weather is a newly developed heat pump using both ambient air and heat from the drive system components to heat the cabin rather than relying solely on the high-voltage heater. VW said this contributes to reduce on-board electrical consumption significantly, especially in winter driving.
Per VW, the Golf A7 was developed from the outset to be a Battery Electric Vehicle (BEV). Volkswagen was able to integrate the lithium-ion battery in a space-saving frame in the vehicle floor, under the front and rear seats and in the center tunnel. Like the electric motor and the transmission, the battery was also developed in-house at Volkswagen and is made at the company’s facility in Braunschweig, Germany.
The liquid-cooled lithium-ion battery accounts for 701 pounds of the e-Golf model’s 3090-pound curb weight. VW said it is composed of a total of 264 individual prismatic cells, which are integrated into 27 modules, each with six or twelve cells. Collectively, the cells have a nominal rating of 323 volts, with an overall capacity of 24.2 kilowatt-hour. A battery management controller (BMC) performs diagnosis and monitoring functions and also regulates the temperature balance in the battery junction controller; when the car is not in use or in the event of a collision, the BMC automatically cuts off power from the battery.
The e-Golf’s battery is charged via the car’s 7.2 kilowatt onboard charger. The optimal solution is the available 220-volt wallbox for a garage or carport: this charges at 7.2 kilowatt, enabling a completely flat battery to be fully charged in less than four hours. If a 220-volt connection is not available, the most cost-effective and easiest alternative is to plug the standard charging cable into a 110/120-volt electrical socket, which will take around 20 hours to charge the battery.
The e-Golf is equipped with the Combined Charging System (CCS) plug for access to CCS-equipped DC fast charge stations. These allow the battery to be charged to 80 percent in around 30 minutes. For added flexibility, the charging process can be activated—immediately or programmed for later—by pressing a button next to the charging socket under the ‘fuel cap’ or through an available iPhone or Android app.
VW explained the e-Golf has three driving profiles: ‘Normal’, ‘Eco’ and ‘Eco+’. The car automatically defaults to ‘Normal’ mode upon start up. To extend the range, the first option is the ‘Eco’ mode, which pares back the electric motor’s maximum power output to 94 horsepower and the starting torque to 162 pound-foot. In parallel, the electronics reduce the output of the air conditioning system and modify the response curve of the accelerator pedal. In Eco mode, the e-Golf is limited to a top speed of 72 mph and 0 to 62 mph acceleration is increased to 13.1 seconds.
In ‘Eco+’ mode, the electronics limit the power output to 74 horsepower and the starting torque to 129 pond-foot, further flatten the accelerator pedal response curve and the air conditioning is switched off. The e-Golf now reaches a top speed of 56 mph and accelerates at a correspondingly slower rate.
Full power, maximum torque, and the 87 mph top speed can be obtained if the driver depresses the accelerator pedal fully down in either ‘Eco’ or ‘Eco+’ mode.
In addition to the driving modes, the regenerative braking system can also be used to manage range, per VW. There are three driver-selectable levels available: ‘D1’, D2’, and ‘D3’/‘B’. It works like this: to switch to ‘D1”, ‘D2”, or ‘D3”, the driver taps the “shift” lever to the left once, twice, or three times. Tapping the knob to the right moves sequentially back to ‘D’.
In an electric car this amount of flexibility can lead to a different way of driving. It is possible to use regenerative braking consciously to slow the e-Golf down. Level ‘D1’ regenerates energy and slows down the car the least, while level ‘B’ has the strongest effect. At levels ‘D2’, ‘D3’ and ‘B’, the deceleration via regenerative braking is so strong that the brake lights come on automatically. However, if the battery is fully charged, no energy regeneration takes place.
Volkswagen said it took very specific measures to lower the e-Golf model’s wind resistance. Among these were: reducing the volume of cooling air via a radiator shutter and partially enclosed radiator grille; new underbody paneling; a rear spoiler and C-pillar air vanes to better manage airflow at the tail of the car; and cleaning up the airflow around the wheels, largely by ensuring they are flush with the wheel arches. VW did not yet release the e-Golf’s coefficient of drag (Cd).
Specifically tailored acoustics of the e-Golf was a priority for VW, aiming to make it an almost silent cruiser. For instance, the powerplant’s subframe was changed to a pendulum mount: despite the electric motor’s high torque build-up when accelerating, this greatly enhances the acoustics. The motor housing unit was also specifically designed to achieve an extremely low level of noise emission. Finally, the interior uses highly sound-absorbent and yet very lightweight materials to produce a vehicle that is quieter than many luxury cars.
On launch, VW said the e-Golf will feature as standard a new assistance system called the Automatic Post-Collision Braking System. Studies in accident research have shown that about a quarter of accidents that involve personal injury are of the multi-collision type—in other words, there’s a second impact after the initial collision.
VW explained the APCBS automatically slows the vehicle when it is involved in an accident in order to significantly reduce its residual kinetic energy. The system is triggered based on detection of a primary collision by the airbag sensors. Vehicle braking by means of the system is limited by the ESC control unit to a maximum rate of 0.6 g. The driver can ‘override’ the system at any time; for example, if the system recognizes that the driver is accelerating, it gets disabled. The automatic system is also deactivated if the driver initiates hard braking at an even higher rate of deceleration.