## SLS AMG E-CELL electric super sportscar slated for production in 2013

##### 10 January 2011
 SLS AMG E-CELL Click to enlarge.

Mercedes-AMG plans to begin production of the SLS AMG E-CELL electric super sportscar (earlier post) in 2013, said Dr. Dieter Zetsche, Chairman of the Board of Management of Daimler AG during the company’s press conference at the North American International Auto Show. Mercedes first announced development of the electric gull-wing sportscar in July 2009.

The four synchronous electric motors in the SLS AMG E-CELL deliver a combined 525 hp (392 kW) of power and 649 lb-ft (880 N·m) of torque. The four compact electric motors each achieve a maximum rpm of 12,000/rpm and are positioned close to the wheels, substantially reducing unsprung masses compared with wheel-hub motors. One transmission per axle transmits the power.

The race for the best super sportscar with electric drive is on.

—Dieter Zetsche

The SLS AMG E-CELL drive features a liquid-cooled, high-voltage lithium-ion modular battery pack with an energy content of 48 kWh and a capacity of 40 Ah. The maximum electric load potential of the battery, which consists of 324 lithium-ion polymer cells, is 480 kW. One of the technical bases of this performance is the intelligent parallel switching of the individual battery modules, which also helps to maximize the safety, reliability and service life of the battery, according to the company. The 400-volt battery is charged using targeted recuperation during braking.

 The incorporation of the electric drive components required no changes whatsoever to car’s weight-optimized aluminum spaceframe. Click to enlarge.

The electric-only drive system was factored into the SLS development process at the concept phase. Its packaging is designed for the integration of the high-performance, zero-emissions technology, enabling the four electric motors and two transmission units to be positioned as close to the four wheels as possible and very low down in the vehicle.

The same applies to the modular high-voltage battery—its component parts are located in front of the firewall, in the center tunnel and behind the seats. Benefits of this solution include the vehicle's low center of gravity and balanced weight distribution—ideal conditions for optimum handling, and something the electric-drive SLS AMG shares with its gasoline sibling.

The additional drive to the front wheels necessitated a new front axle design. Unlike the series production vehicle with the AMG V8 engine, which has double wishbone suspension, the SLS AMG E-CELL features an independent multi-link suspension with pushrod damper struts. This is because the vertically-mounted damper struts in the series-production SLS had to make way for the additional drive shafts. Frequently found in racing cars, the new horizontal damper units are actuated via separate pushrods and transfer levers.

Another distinguishing feature is the speed-sensitive, rack-and-pinion power steering, with the power assistance operated by electro-hydraulics rather than conventional hydraulics.

The braking system on the prototype features AMG ceramic two-piece brakes, available as an optional extra on the series production model. It delivers extremely short stopping distances, a precise actuation point and outstanding fade resistance, even under extreme operating conditions. The generously dimensioned, radially floating rotors measure 15.83 x 1.54 inches at the front and 14.17 x 1.26 inches at the rear and are made of carbon fiber reinforced ceramic composite material connected to aluminum hubs.

The ceramic brake discs are 40% lighter than the conventional, gray cast iron brake discs. This reduction in unsprung mass improves not only handling dynamics and agility, but also ride comfort and grip. The lower rotating masses on the front axle also ensure a more direct steering response—which is especially effective in high-speed cornering. The ABS and ESP systems have been adapted to match the particular operating spectrum of the permanent all-wheel drive.

It looks like Tesla may have serious competition. Four e-motors with four mechanical transmissions, that's a lot of mechanical parts. Four light weight in wheel e-motors could have been another solution? The use of very light weight materials for the wheels, b rakes, tires etc could have reduced the added unsprung mass.

A Mercedes-AMG EV w/2X Tesla hp. may be 4 times the price.

If you have looked at SL specifications in the past, it is a short wheel base car that weighs TWO tons. The SL has weighed over 4000 pounds for decades. You can offer ceramic disk brakes, but small weight reductions are a drop in the bucket when your overall car is just too heavy.

Its a stupid design as it only has 48 kwh its like a v12 supercar with a 6 gallon gas tank.

They would likely need at least 160 kwh to give it enough range at speed to function as a barely passable sports car let alone a super sports car.

Instead of, "the race is on for the best super sportscar" EV, I wish is were a race for the best affordable family sedan EV.
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On the bright side, this high-end development will spill into the more mundate stuff.

"They would likely need at least 160 kwh to give it enough range at speed to function as a barely passable sports car let alone a super sports car."

Perhaps they can improve it as battery performance advances.. in any case the Tesla Roadster gets 244 miles of range with a 50kwh pack, why would this car be much worse?

@Herm - The battery pack is only 48 kWh in capacity, but the motors are capable of drawing nearly 392 kW.

That means that it's possible to drain the battery pack in 7 minutes at full throttle.

Now the top speed will likely be electronically limited and thermal limits will also likely limit the amount of sustained power draw, but a handful of laps around a racetrack (where this car should spend some time) should rain the pack in well under 30 minutes. Even in spirited driving it shouldn't be hard to drain the pack in well under an hours.

Driven sensibly you could get 150mi+ out of it (it won't be as efficient as a Tesla Roadster due to the weight and wider tires).

Very likely the acceleration will be second to none - so the car will still sell in limited numbers depending on price.

Okay, someone has to say it... An even more stupidly expensive "super" sportscar toy for the super rich??? A heresy to the collective!!!

Oh, and it's still just vaporware. But we welcome all EV contributions to the party.

I don't get it.
These are for blasting along Autobahns at 120+ mph for hundreds of miles.
They won't have the energy storage for that.
Plenty of acceleration, but no range - not at the speeds this is intended for.

(I think it needs a diesel range extender.)

If they put in that tiny rotary-engine range extender from Audi it would be much more practical for only an extra 100 kg, inlcuding fuel tank etc.

Eventually more of the readers of this news will realize that when it comes to automobiles, horsepower and or kW, are not well understood and almost always misstated for sales purposes. At Zero vehicle speed, even the largest motors or engines produce no horsepower, but they can produce a lot of torque. Ten kW is good enough for most level freeway travel.

Assuming 250 watt-hours per mile at a relatively efficient travel speed, 40 kWh will allow 160 miles of travel at about 54 mph in three hours. This gives an average horsepower of about 13 kW or about 17 PS. This is far less than the nearly 500 kW available from the batteries.

Because of wind resistance, high speed is much less efficient, but the US government will not impose the 55 limit even though is would make the need for ethanol and bio-diesel vanish. ..HG..

Henry... Henry... EVEN If I drive my Prius at 55MPH all day, I am STILL going to have to refill the gas tank with oil cartel-produced fossil fuel.

The REASON for transitional biofuel in light transportation is to help END OUR DESTRUCTIVE ADDICTION TO UNSUSTAINABLE FOSSIL FUEL!!!

This is a cool technological tour-de-force, but it's a silly car. I suppose you could arrive guilt free at the red carpet in Hollywood to attend the Oscars in this, so there may be a sliver of a niche market. The Jaguar concept with the twin turbine range extenders was much more coherent as something usable for its intended purpose.

I am more interested in the car that gets twice the mileage, that will sell by the millions of units because it represents a good value. If we are going to have a significant effect on imported oil we need to have wide spread adoption of whatever we do.

My feeling about in-wheel electric motors not being such a good idea wasn't that silly afterall. I didn't make the argument about un-sprung weight, whatever that is.

Sprung weight is the frame and body, the wheel is on the other side of the suspension spring and is thus unsprung.

I knew that.

Good, your comment "whatever that is" led me to believe that you did not.

aparrently the "light" motors are mounted "close to the wheels".

OK so the motors are light,if high power presumably will be be high efficiency but one does not need to drive full throttle nso no issue there. They arer probably robust in construction and could com e in handy four pulling the occasional road train out of a bog - as you do.
"Close to the wheels"(Bad wording) looks awfully like dead center of the axle "to reduce unsprung weight." I've been advocatingng this duaul E motor centre mount forever and I am pleaded to note that intelligent designers at Mercades agree with me.- points to both of us.

The weight?not mentioned however the 'flash' shockover push rod and horizontal "modular" (aluminum?) suspesension and the other overlay desighn drawings provde hints to lightweight aluminum chassis construction and modular mounting componentry.
"generously dimensioned, radially floating rotors measure 15.83 x 1.54 inches at the front and 14.17 x 1.26 inches at the rear and are made of carbon fiber reinforced ceramic composite material connected to aluminum hubs.

The ceramic brake discs are 40% lighter than the conventional, gray cast iron brake discs. This reduction in unsprung mass improves not only handling dynamics and agility, but also ride comfort and grip. The lower rotating masses on the front axle also ensure a more direct steering response—which is especially effective in high-speed cornering. The ABS and ESP systems have been adapted to match the particular operating spectrum of the permanent all-wheel drive."
That doesnt sound like a two ton tessie to me.

It also comes with ESP or in my feeble little mind this car plainly has extra sensory perception.

I think you previous posters are just JEALOUS.

Apologies for the typo's, Just getting a bit excited and planning to buy or make one of these for the slot car track!

...Reel$$...Reel$$ Thanks for pointing out the critical issue of automobiles and Semi-trucks and planes and trains in constant motion throughout the day and night. Most automobile use is not of that type, but the related issue of existing automobiles that use liquid fuels and are not soon to be replaced is critical.

Coal and natural gas can be used to produce liquid fuels far below the present cost of production of ethanol or fuels from crude oil, and in the near term, coal and gas can be released for such use by nuclear power generation.

There is no such thing as renewable energy. Atoms are being destroyed in the sun to produce sunlight, and its use on the earth is very inefficient, and more than ten zeros after the decimal point(<0.00000000001) is needed to show this efficiency. Enough uranium and thorium exist upon the earth to supply industrial and home energy at the current rate for billions of years until the earth is swallowed by the expanding sun, but they remain fossil fuels.

Uranium and thorium cannot be exhausted in the next thousands of years, but it is very likely that useful hydrogen fusion will be developed within the next thousand years or so and this will enable not only the production of electricity but also the production of a great deal more plutonium 239 than can be produced from the excess neutrons of a fission chain. This material can be used in bombs but also in very small fission reactors. Plutonium 238 can also be produced from nuclear "waste" materials with these excess neutrons.

Used fuel rods contain about 95 percent remaining useful fuel, but from one of the remaining other elements, Plutonium 238 can be made in fission or fusion reactors. Plutonium 238 will not fission in the way needed for nuclear bombs, but produces a lot of heat. Plutonium 238 was used for very long life electric supply in early cardiac pacemakers. It is also used for heat and power for space exploration beyond the earths orbit where the sun looks more and more like any other star.

Plutonium 238 could be used without any significant danger to power an automobile. It is far less dangerous than 10 gallons of gasoline. Bill Gates or his friend Warren Buffet could afford to buy a Plutonium powered automobile that would drive continuously for fifty to hundred years without refueling.

A small aircraft could also be built which because of a lack of inflammable fuel would be safer for those in the plane and on the ground in the event of a crash. Most of the radiation of the element is contained in itself and almost all of the rest is contained by a few millimeters of steel. The metal is always very hot, and the heat can be used to drive a Stirling engine or steam engine to produce mechanical or electrical energy. A partially molten mix of fluoride salts can be used to store a great deal of this heat for high bursts of power from the engine.

France and Russia are in a good position to produce Plutonium 238 in large amounts, and the president of France and Putin should be driving plutonium 238 powered cars as an example to the world of ultra low carbon travel. ..HG..

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