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Boxster E with Four Wheel-Drive

The Boxster E is an all-electric vehicle without any additional combustion engine on board. Propulsion is provided by two independent electric motors with constant mesh gearboxes that act on the front and rear axles. The rear drive unit comprising motor and transmission, together with the power electronics for controlling the electric motor is located where the manual transmission and exhaust system are accommodated in the conventional Boxster. In the front end, the space vacated by the 64-liter fuel tank, now redundant, is occupied by the second drive unit. The power electronics unit in the adjacent luggage compartment serves the front axle electric motor. The Boxster E thereby features all-wheel drive without mechanical transmission of power. To ensure maximum driving stability and traction, a central electric control unit looks after the synchronisation of the two electric motors and controls the drive torque distribution to the front and rear axle.

The two electric motors develop a total power output of 241 hp (180 kW) and a maximum total torque of 398 lb-ft (540 Nm) at a maximum engine speed of approximately 12,000 rpm. That means that the two electric motors in tandem deliver significantly higher drive power than what is available from present day hybrid vehicle electric power units. As well as the all-electric drive of the Boxster E producing zero tailpipe emissions, it also offers a completely new form of Porsche driving pleasure. Maximum torque of the electric drive kicks in virtually from the first turn of the engine. The Boxster E moves almost silently while at the same time developing powerful propulsion from the very outset.

The two motors enable the two-seater to sprint to 60 mph in 5.3 seconds from a standing start. Its top speed, limited to 124 mph (200 km/h) is achieved without any gear change at all - whether automatic or manual. The high power output of the two motors offers a second advantage: it means more recovered power is available because more energy can be recovered during braking. This increases efficiency of the drive unit.

Boxster E with Rear Wheel Drive

In the case of the two other Boxster E models with rear wheel drive there is no front electric motor, therefore delivering a power output of 120 hp (90 kW) and a rated torque of 199 lb-ft (270 Nm). This model can sprint from a standing start to 60 mph in 9.2 seconds, with a top speed of 93 mph (150 km/h).

Active Sound Design

As all Boxster E models are comparatively quiet on the road, Porsche engineers have designed an Active Sound Design system that provides drivers with acoustic feedback as well as alerting pedestrians and other road users.

New Expression of Porsche Intelligent Performance

Irrespective of variant, the heart of every Boxster E is manufactured by Porsche. The lithium-iron-phosphate based traction battery is fitted in place of the combustion engine. Each of its cells has a nominal voltage of 3.3 V and an individual capacity of 20 Ah. Based on the NEDC, the combined energy from 440 individual cells is good for approximately 107 miles (170 kilometers) of driving in the Boxster E with its ready-for-the-road weight of a mere 3527 lbs (1,600 kg).

For an overall weight of 752 lbs (341 kg), the battery's energy content is 29 kWh of which for inherent physical reasons approximately 26 kWh are available for use - an outstanding performance for a battery.

Its maximum power output is 240 kW, or 60 kilowatts more than the all wheel-drive Boxster E draws under full load. The battery and power unit components are connected to two water cooling circuits. As with the conventional power unit, the heat exchangers are accommodated behind the front air intakes.

The battery is anchored to the same points on the body structure as the combustion engine in the Boxster S. There are numerous advantages to this, especially in the event of a crash, because by using the same load paths as in the Boxster S, the battery is optimally retained within the vehicle while at the same time being protected from damage by the surrounding body structure thanks to its central position within the vehicle. As with the combustion engine in the production car, the traction battery is installed in the Boxster E from below and can be swapped out very quickly if so required. This is also facilitated by special motor sport fasteners that enable the battery to be disconnected from the cooling circuit without air getting into the system.

Charging the Boxster E

The traction battery is charged via a charging cable. Any conventional socket can be used as an energy source. The charging port on the vehicle features an illuminated ring and, as with any Porsche sports car, the vehicle is 'refuelled' (in this case, recharged) at the front end. The charger is accommodated at the front of the car. It converts alternating current from the socket into direct current, enabling the traction battery to store the electric energy. Its charging capacity is a maximum of 3.3 kW meaning that it takes approximately nine hours for a full charge. The charging time can however be reduced using a rapid charging function. There is enough space left over for luggage in the front storage compartment despite the electronic components; the rear luggage compartment of the Boxster E remains unchanged.

Porsche Boxster E Concept: Photo Gallery, Review (1/2) and Specifications