Getting a sneak peak at the Tesla Showroom was a great experience. I knew a little about the car from what I had read, but getting to speak to the director of parts and sales gave me much more insight as to how this mean little electric car works. Keep on reading if you want to learn a bit more about what’s under the Lotus Elise inspired carbon fiber bodywork (warning, this is gonna get a bit technical).
Well, let’s start with the bodywork. Yup, it’s carbon fiber. It’s carbon fiber because they needed to keep the weight of this vehicle as low as possible. Keeping with the lightweight theme, the Tesla uses bonded aluminum tubular frame manufactured by Lotus to hold everything together. Contrary to what some of the literature on the net might have you believe, using aluminum for this car’s chassis is not really *breakthrough* or *revolutionary*. While Lotus’ bonding techniques may be a relatively new technology, the idea of using aluminum in cars has been in racing since at least the 60′s (the Ford GT40 used an aluminum monocoque). If you look to production cars, the Corvette Z06 has been using aluminum frames for a couple years (albeit with a totally different construction technique), and the Lotus Elise which this car shares many design features with has been using a similar bonded aluminum frame since it’s release in 1996. It may not be new, but it certainly is an excellent, lightweight (and expensive) way of making frames.
So what’s with the huge lightweight push? Well, mass is a car’s #1 enemy. It hurts every single aspect of performance. And there’s still a huge problem with all electric cars which not even Tesla Motors has found a solution to: batteries. Current battery technology just plain out sucks. The batteries are big, heavy and expensive. The heavy part is probably the biggest challenge in making a performance electric vehicle. Tesla’s battery pack weighs about 900 lbs, and that’s using some of the best lithium-ion battery technology out there. They NEED to make everything else in the car absurdly light just to make the car a viable performance roadster. Although to be honest it doesn’t seem like they’ve gone that far above and beyond to get the car super light. I mean, the Tesla’s curb weight of ~2700 lbs is about 700 lbs heavier than the Lotus Elise. I may be wrong here, but swapping out the old combustion engine and transmission for an electric motor and 1 speed transmission has got to save some weight.
The suspension is a proper double A-arm setup on all four corners. It’s nice to see that it doesn’t look as though they compromised the suspension geometry in order to package the battery load. The A-arms themselves appear to be made out of aluminum, and I believe they are also manufactured by Lotus for Telsa.
Wheels are aluminum, with a 16″ diameter in the front, and 17″ diameter in the rear wrapped in Yokohama AD07 Advan LTS Tires (same setup as the Lotus Elise). Brakes are Brembo calipers and rotors. Nothing too special here, just simple, quality parts.
Now we get to the fun part. Finally, the part that sets this car apart from most everything else out there: it’s electric drive-train. The heart of the drivetrain is the in-house designed 3-phase, 4-pole electric motor that has a max output of 185kW (that’s 248 hp). But what’s really cool about electric motors, are their torque curves:
Peak torque right off the bat. That means fun fun fun!
Tesla not only developed the motor, but also the motor controller that feeds the motor current when you smash that “gas” pedal (are we going to have to start calling them accelerator pedals?). The motor controller is packaged under the hood of the car, along with the radiator for the batteries.. Wait a second, did I just say radiator? Yup, i did. This brings us to the final component of the electric drivetrain, the battery pack. And it’s one sweet battery pack.
The battery pack is comprised of 6831 lithium-ion cells that are slightly larger than a standard AA battery. You might recall that Lithium-Ion batteries can sort of have a heat problem. To combat this, they use an active liquid-to-air cooling system, in which much like an internal-combustion car, the radiator is placed up front under the hood. The battery weighs about 900 lbs, and Tesla claims it has a life of about 100,000 miles.
Well, that about sums up what i learned at my visit to the dealership. If i came across overly harsh on Tesla, let me tell you that wasn’t intentional. I think it’s a great car, but I also think the Lotus Elise is a fantastic car, and from what I see, the Tesla is basically just a electric motor version of the elise. It’s unfortunate that the luxury of having an electric drivetrain will cost you about $60,000 more than the base Lotus Elise, because I’d love to have one of these cars.