Tesla Roadster
The Tesla Roadster is a fully electric -powered, two-seat sports car. He is the first production car from Tesla Motors.
July 24, 2006 Tesla Motors introduced the Roadster before in a closed event at the Santa Monica Airport in California. The small series production began after several delays on March 17, 2008.
Drive
The two-seater sports car is powered by a 215 kW ( 292 hp) electric motor in the rear. The maximum torque of 370 Nm (400 Nm at sports version ) is up to at speeds of 0-5400/min. The originally planned rear axle two-speed gearbox has been discarded since the prototypes did not meet the requirements for the longevity of the vehicle. Instead, the final production form has a transmission with only one gear. All made to the date of transition Tesla Roadster initially received the two-stage Vorseriengetriebe, however, this is locked in second gear to limit the applied mechanical load forces. This solution was replaced under warranty with all vehicles sold so later against the input gear.
With the final gear the vehicle reaches approximately 3.7 seconds 100 km / h, previously delivered models need for or 5.7 seconds. To protect the gear mechanism and reduce the demand on battery power, the Roadster is in favor of the range at 201 km electronically limited / h (125 mph).
Chassis and Body
The Roadster was developed in collaboration with AC Propulsion and Lotus. Unmistakably bears the body, the design signature of the British sports car manufacturer Lotus, whose work has also taken over the series production in Hethel. Landmark was the Lotus Elise, of the many components were taken. Both cars use the same aluminum frame, the Danish Lotus supplier Hydro Aluminium developed. The frame weighs only 65 lbs and is not welded, but glued and screwed. This framework was also the Opel Speedster used. The body is made of carbon fiber reinforced plastic.
The fully assembled car weighs about 1240 kg, is 3.94 m long and 1.87 m wide.
In addition to the soft top mounting a hardtop is provided.
Energy storage
The energy storage system consists of 6831 cells commercially available lithium -ion batteries for laptops. The battery stores 56 kWh ( approximately 20% is lost during charging, so about 70 kWh are needed for a charge ), which are delivered with a voltage of 375 volts to the motor. In the lithium ion battery cells is the type 18650, which is produced annually in several million copies. The entire battery is composed of eleven sheets connected in series, each containing nine also connected in series block; in each block each 69 cells are connected in parallel ( 11S 9S 69P ). Each battery cell is 65 mm long and has a diameter of 18 mm. The whole package weighs about 408 kg 6831 cells. Each cell has two fuses, as well as one at the anode to the cathode. The entire battery pack is cooled by a mixture of water and glycol.
Based on the U.S. official driving cycle, the manufacturer promises a range of 350 km. In practice, observed ranges were between 200 km ' at brisk ride " and 501 km.
The high range in spite of only 56 kilowatt hours of energy content - which is the calorific value of just over 6 liters of gasoline - is possible because electric motors in terms of mechanical efficiency are more efficient than internal combustion engines, which instead of the chemical energy of the fuel in large part to heat to the desired movement converting ( 25 % efficiency in internal combustion engines, > 94% at the electric motors ). In addition, the electric motor acts as a generator during braking, and so can convert a portion of the applied kinetic energy again into electrical energy. This saves especially in city driving energy.
The charging time is with AC connector with optimal conditions 1.5 to 2 hours (400 V three-phase 63 A). With a 32 A three-phase connection, the charging time is about three hours, at 16 -A terminal six hours. If only a 230 V/16 A AC outlet is available, a complete charging cycle can take up to 20 hours.
Life and cycle stability
Plug in America has among drivers of the Tesla Roadster, a survey carried out on the lifetime of the installed batteries. It was found that after 100,000 miles = 160,000 km, the batteries still had a remaining capacity of 80 to 85 percent. This was regardless of climate zone in which the vehicle was moved.
Energy sales
The energy demand is on average 12.7 kWh per 100 km, based on the energy content of gasoline, this corresponds to 1.49 liters per 100 km. The vehicle itself is emission-free, but CO2 and other pollutants can be released in case of electricity generation, depending on the type of power generation. While renewable energy can be found almost lossless available ( for example, via decentralized photovoltaics), would be a primary energy factor of 2.6 (as of 2009 ) requires about 33 kWh of primary energy in generating the current electricity mix in Germany, which is about 3.3 liters of fuel oil ( HEL) or diesel equivalent.
The manufacturer's website indicates an energy efficiency including energy supply and generation (Well- to-wheel = source to wheel) of 1.14 km / MJ (equivalent to 24.4 kWh per 100 km). This corresponds to vehicles with a fuel consumption of about 2.2 liters of petrol or diesel or 1.5 kg of natural gas (H- gas ) per 100 km of track. The electric energy supply and generation from natural gas is assumed to have an efficiency ( well-to - station = source to petrol station ) of 52.5 %, the well-to- station efficiency of diesel with 90.1 %, gasoline 81, 7% and natural gas at 86%.
Criticism
Often skeptical, especially of representatives of major car manufacturers, the promised durability of the battery pack in the rear between the driver seat and engine is seen because lithium -ion batteries in their opinion had sufficient endurance for use in a motor vehicle. Tesla Motors but considers that there are extreme temperatures, the batteries could be aging rapidly, namely cold in mobile phones and laptops heat. Therefore, the battery pack of the Tesla Roadster will permanently washed by tempered liquid to ensure optimum temperatures of 18 to 25 ° C. In May 2011, a rider reached with his Tesla Roadster 100 thousand kilometers and a year later even a further 200,000 km mileage, which is regarded as an indication of sufficient battery life.
See life cycles and strength.
Cost and production
The price for the basic equipment of the car is 109,000 dollars. A full charge of the battery pack ( for 350 km range ) cost about two to three dollars, according to U.S. prices in 2008.
2000 copies per year should be made at the beginning in the Lotus Hethel factory in the UK. The production began on March 17, 2008. Prospects could be put on Tesla's website against a deposit of U.S. $ 60,000 ( 50,000 EUR in Europe) on a waiting list.
After the Roadster was first offered only in North America, he is since May 2009, also available in Europe. But first, a limited edition of 250 units of special edition Signature Edition at a price of at least EUR 117 810 was created. The European model should have a more powerful engine, a modified gearbox, special dampers and special wheels. The last model available 2.5 points compared with the first models to minor adjustments.
The end of 2012 the production of the Roadster was set and started the production of the Tesla Model S.