RUF introduces the first SUV with electric powertrain

eRUF Stormster

RUF Automobile GmbH, located in the small Bavarian town of Pfaffenhausen, the manufacturer of high performance automobiles, introduced the first electric sports car (eRUF) from Germany in October 2008.

During the Geneva Motor Show, in March 2009, RUF presented an evolution of the first eRUF, widely known as "Greenster". The eRUF family continues to grow with the unveiling of the "Stormster", the very first electrically driven SUV based on the Porsche Cayenne.

The Stormster is driven by a Siemens electric motor, with 270 kW (367 bhp) as in the eRUF sports car. The total weight is 2,670 kg which makes it capable of reaching 100 km/h in only 10 seconds. The top speed is 150 km/h, being able to reach a range of 200 km at one charge.

The lithium ion accumulators are supplied by Li-Tec Battery GmbH. Li-Tec is the first manufacturer of lithium ion battery cells in Europe, designed for the automobile industry using ceramic storage technology.

Hankook developed the winter tires for the all wheel drive Stormster which is fitted to RUF classic 5 spoke lightweight wheels. Tires of size 295/30 R 22 allow the best possible road grip.

The Stormster will have its first public debut during the European Climate Change Conference in Copenhagen, (COP 15), Denmark from December 7^th to 18^th.

[Source : RUF]

Ruf Dakara : World innovation at Geneva Motor Show

Ruf Dakara

GENEVA, Switzerland, 5 March, 2009 - The High Luxury SUV built by RUF is named Dakara and is based on the Porsche Cayenne. The exterior and interior is able to embrace the most ambitious wishes.


Four 22 inch- five spoke wheels and the broadened fenders demonstrate pure power. The bodykit fits to every Cayenne. Cameras in the front and in the back of the Dakara cater for the panorama view. The interior room is affected by complex processed leather trim which does not only fascinate with the precious materials but also with the new designed seats.

A High-End Multimedia system with TV-reception, access to the internet and a CD-/DVD-Changer will gratify even the highest requirements. The V8-Turbomotor offers an engine output of 600 horsepower (600 Ps) at 6000 rpm. The maximum torque of 659 lb-ft/lbs (890 Nm) is delivered at 3000 rpm. So the Dakara is able to reach the speed of 62 mph (100 Km/h) in 4.8 sec.

The chassis as well as the brake system are adjusted to the high requirements. Even ceramic-composite brakes are available.The Dakara perfectly ties in with the RUF model-range.

Images : Ruf Dakara

[Source : RUF]

RUF unviels Electric 911 : eRUF Concept Model A 2008

PFAFFENHAUSEN : October 10, 2008 - Ruf Automobile GmbH, internationally well known manufacturer for high performance automobiles and the producer of the famous CTR-series is now introducing the first electrically powered sports car from Germany.


The fundamental ideas that lead to the development of the eRUF concept vehicle came from Alois Ruf. The car maker from the Bavarian town of Pfaffenhausen had a vision of a simple energy transfer concept: his hydroelectric power plants, which feed 35 million kW hours of electricity annually into the German electrical network, could also more or less directly power modern autos. 35 million kWh is enough energy to power one of the prototypes eRUF as described below for 3500 journeys around the globe – or 3500 of the cars one time around the world each.


The idea seemed even more inspiring, as it would be possible for him to connect cars directly to the emission-free power plants for charging and drive away on the water-generated power.

The eRUF Model A concept car is the first prototype to lead the technical development away from the combustion engine. Actually, for the first time an electric motor is being used which comes to fitting into the Ruf model range.

The three-phase AC motor’s performance easily puts many conventional conbustion engines to shame. It produces its maximum 650 Nm torque output from 0 rpm onwards. This power rips into the drive shafts so impressively during acceleration, that one is immediately reminded of the extremely powerful Ruf Rt 12 It is actually enough simply to put the car in 6th gear and press down the accelerator pedal (an “amp pedal”, not a “gas pedal”in this car!), and drive off.


The eRUF Model A has such impressive acceleration that the project goal of 0-100 km/h in under 7 seconds was achieved.

The maximum power output is around 204 hp if you translate it into combustion engine terms. In direct connection to Volt and Ampere the maximum output level of 150 kW is a useful figure.

A short discourse regarding efficiency might be helpful at this point: a highly-developed, modern petrol engine uses around 75 percent of the energy in its tank to heat the engine coolant and exhaust gas and only 25 to 30 per cent for actual propulsion. A diesel manages to convert a respectable 35 to 40 percent of its fuel energy into motion. The permanent magnet electric motor, on the other hand, is a model of high efficiency: it offers over 80 percent efficiency over the majority of its power range, extending 90 per cent in the upper end of its power range.

Ruf engaged CALMOTORS in Camarillo, California, specialized in the implementation of hybrid electric and electric only power train designed to combine the latest generation of lithium-ion batteries with its motor. Since the 150 kW electric motor unit is very compact, there is a lot of room for batteries in the Ruf’s bodywork.

The Axeon iron-phosphate, lithium-ion batteries currently in use weight 5.6 kg and deliver 160 Ah each. This means each one could theoretically deliver 160 amperes of electricity for one hour under normal temperatures or 1 ampere for 160 hours. The generation of batteries available from Axeon represents by no means the end of the developmental curve. Current performance improvements in battery technology indicate that end of this improvement spiral is nowhere near.

The driving current in the eRUF is regulated by an electric “drive-by-wire” accelerator pedal. It is not the first electrical accelerator in a Ruf model. Other Ruf models also provided load control via potentiometer-pedals, nicely dosed for their powerful engines.

The power and torque produced by the 3-phase motor can be used to recover just as much power as it can put out. When coasting, the motor becomes a generator producing electricity to charge the batteries. The torque and electrical amperage ratings below are therefore to be understood as theoretical absolute maximums and minimums.

The 96-cell battery system is constantly monitored by an intelligent bus system from Axeon. Each individual cell is coupled with a sensor that sends critical information on cell temperature and voltage to the central control system. If irregularities appear during operation, the system can react within milliseconds to bring the values back in line, effectively preventing critical lithium-ion overheating behaviour during charging.

Specification status of September 2008
All data are preliminary data as specified for the eRUF Model A

Drive Performance
· Acceleration 0-60 mph under 7.0 sec (development target)
· Vmax 160 mph, 225 km/h
· Cw 0.28
· Roll resistance 0.014
· Driving range approximately 250 – 320 km, depending on performance level
· Specific power pick-up 21 kW / 125 km/h

Vehicle data
· Engine power 150 kW / 204 PS
· Max torque 650 Nm 7 0 rpm
· Weight 1910 kg (preliminary data)
· Battery weight 550 kg

Motor Data
· Max torque + 650 Nm to -650 Nm
· Power + 150 kW to -150 kW (peak level) + 204 hp to -204 hp 100 kW / 136 hp continuous
· Currency 300 – 420 Volt
· Current level max 550 A
· Rpm level max 5000 rpm
· Operating system brushless three phase alternating current with permanent magnets

Dimensions
· Diameter 405 mm
· Length 241 mm
· Weight 91 kg
· Specific weight 1,65 kW / kg, 2,25 hp / kg
· Coolant flow 8 L /min max

Battery System
· Type Lithium-Ion, iron-phosphate base
· Manufacturer Axeon plc, GB
· Stored Energy (96 units) 50,72 kWh
· Nominal Voltage 317 Volt
· Maximum discharge 480 A
· Max Power 152,16 kW = 210 PS
· Charging current, max. 16 A
· Charging time 10 hours

Single Battery Cell Data
· Capacity 160 Ah
· Operating voltage 4,25 V charging, 2,5 Volt discharging
· Nominal Voltage 3,3 Volt
· Max. Temperature Level 80 °C
· Life cycle 3000 charging cycles
· Self-discharge under 3 % per month
· Weight per Unit 5,6 kg

[Source : RUF]