Volkswagen has provided an update on its Golf blue-e-motion electric vehicle (earlier post), now scheduled to arrive on the market in 2014. At the presentation of the concept in Germany earlier this year, VW had said the EV would launch on the market in 2013.
The EV is driven by an electric motor integrated in the front engine compartment with a maximum power output of 85 kW (115 PS, 112 hp) and a continuous power output of 50 kW (69 PS, 67 hp), with 270 N·m (199 lb-ft) torque, powered by a 26.5 kWh lithium-ion battery pack. Top speed is now 135 km/h (84 mpg), versus 140 km/h (87 mph) announced earlier this year. The projected driving range of 150 km (93 miles) remains the same as earlier announced. Power output and top speed are dependent upon the selection of driving profile (below). Acceleration from 0 to 100 km/h is 11.8 seconds.
At the car’s production launch, Volkswagen will announce final driving range data of the production version, which it expects to be “significantly improved” with the battery technology to be used in the future. In many locales, VW points out, the needs of commuters are already met by the 150 km range. In Germany, for example, according to the German Federal Statistical Office, 6 of every 10 people in the workforce commute by car. On average, 45.8% drive less than 10 kilometers (6.2 miles) (one-way commute), another 28.1% between 10 and 25 kilometers (6.2 to 15.5 miles) and 16.2% more than 25 kilometers.
The concept car’s 30 battery modules—comprising 180 lithium-ion cells—were installed in spaces adapted to the vehicle architecture: in the floor of the trunk (fully usable cargo capacity: 275 liters, 9.7 ft3), under the rear bench seat and in the center tunnel of the underbody (between the front seats). A separate air cooling system ensures a constant thermal environment in the battery compartment.
The driver can see how much energy is being demanded at any given moment on the kW gauge (replaces the classic tachometer); drivers strive to keep the kW reading as low as possible practically intuitively. A range indicator is also integrated in this round instrument. The speedometer, located on the right side as usual, integrates another small gauge that provides information on the battery charge state.
A new feature is the display of regeneration intensity in the multifunction display between the kW instrument and the speedometer. In battery regeneration, the driver has the option of pre-setting the braking energy recovery strategy over four stages (D to D3) via the automatic gearshift lever or gearshift paddles on the steering wheel.
In the lowest stage (D), the car sails as soon as the driver’s foot leaves the electric pedal—now the Golf blue-e-motion moves with very low drag. The motor is controlled to the zero-torque curve so that the car can coast with the least possible drag; it is only slowed by the rolling resistance of the tires and air resistance. In the D3 stage, or B for braking, on the other hand, the maximum amount of kinetic energy is recovered and fed to the battery. In addition, the electrical energy consumption of the automatic climate control unit and its blower can be called up in the multifunction display.
Profiles. The driver select priorities in advance with drive profiles: between maximum range, maximum comfort and maximum dynamics. The selected profile then pre-configures the power of the electric motor, air conditioning control, maximum speed and battery regeneration strategy.
The Golf blue-e-motion offers the three profiles “Normal,” “Comfort+” and “Range+”. In the Comfort+ profile, the full 85 kW of power is available; in this mode the Golf blue-e-motion can attain the specified top speed of 135 km/h. When the driver activates the Normal mode, power is reduced to 65 kW and top speed is lowered to 115 km/h (71 mph). In the Range+ mode the engine controller limits power to 50 kW; in this case, the car can reach a maximum speed of 105 km/h (65 mph). At the same time, the air conditioning system is completely deactivated. The selected profile is shown in the multifunction display.
Packaging. All key primary and secondary drive components were integrated in the front engine compartment. In arriving at this design, developers applied experience they had gained in numerous design studies. As in the Up! blue-e-motion concept car, for example, an integral form of electric drive is used in the Golf blue-e-motion. Core components of the integral drive are the lightweight 80 kg electric motor together with a transmission and differential.
Energy management is handled by a high-voltage pulse-controlled inverter that is integrated in the compact integral drive along with the 12 Volt electrical system’s DC/DC converter and charging module. The entire unit is relatively light and compact; the five-door and five-seat Golf blue-e-motion weighs just 205 kg more than a comparable Golf BlueMotion TDI with DSG.