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Driving range drops from 250 miles to 200+ miles

Tesla Motors has been touting its impressive Roadster for quite some time now. The $100,000 sports car boasts impressive specs including a top speed of 130MPH and the ability to accelerate from 0 to 60MPH in just 4 seconds. At the time the Tesla Roadster was first announced, the vehicle was projected to have a range of 250 miles thanks to its 6,381 cell lithium-ion battery pack.

Tesla Motors, however, has just informed its customers who have already put a down deposit on the vehicle that the driving range will come up short. The company can no longer guarantee the 250 mile range after extensive on-road testing. Instead, the EPA certified range of the vehicle is expected to be "greater than 200 miles."

Darryl Siry, VP of Marketing for Tesla Motors, cites a number of reasons for the decrease in driving range. Changes have been made to improve the safety of the battery pack, lower capacity lithium-ion cell had to be used to increase durability and added weight to the chassis to the tune of several hundred pounds have also hindered performance.

"The original premise of this groundbreaking car was that its range would be high enough that you would not have to worry about charging during a typical day, even if you have a long commute, take the car out for dinner and chores, or even take the scenic route home," said Siry. "Once home, you plug it in - just like you would your cell phone - and by the time you're ready for another day, your Tesla Roadster is fully charged and ready to go. We believe that this premise is still intact with a range above 200 miles."

For more information on the development of the Tesla Roadster, you can check out a recent interview with Tesla Motors CEO Martin Eberhard at AutoblogGreen.

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surpiise
By slawless on 4/18/2007 12:01:20 PM , Rating: 4
I still wonder what the true range will be when it is 20 degrees out at night with snow on the ground.

Under a similar seneiro GMs EV1 droped fron 120 to 12 miles.

Also when the batteries are three years old what will be the range.




RE: surpiise
By Falloutboy on 4/18/2007 12:06:04 PM , Rating: 3
EV1 I'm pretty sure used NIMH batteries the tesla uses Li-on which I don't beleave have as much issue with cold. I also remember reading on there site something about temp control in the battery compartment


RE: surpiise
By stromgald on 4/18/2007 12:12:31 PM , Rating: 3
You beat me to it. You're right about the EV1's battery being either lead-acid or NiMH depending on the version. NiMH is one of the most suceptible batteries to low temperatures. LiIon is better, but isn't great either. I think lead-acid and Nickel Cadmium batteries (which are used on many satellites) are the best, but they're also much heavier than LiIon.

Here's some info on battery discharge at various temps: http://www.batteryuniversity.com/partone-15.htm .


RE: surpiise
By RamarC on 4/18/2007 12:08:14 PM , Rating: 5
quote:
I still wonder what the true range will be when it is 20 degrees out at night with snow on the ground.

I've never seen a Ferrari out in that kind of weather. So I doubt if too many Teslas will be out then either. If you can afford a $100K car, you know when to leave it in garage and drive the Range Rover instead.


RE: surpiise
By therealnickdanger on 4/18/2007 12:33:30 PM , Rating: 1
Haven't you ever seen Viva Bam! He drives his Lambo in the snow, through dirt, whereever. There are people that have money and then there are people that have money .


RE: surpiise
By ChuckDriver on 4/18/2007 2:55:45 PM , Rating: 5
... then there are people who have money but no brains.


RE: surpiise
By othercents on 4/18/2007 4:58:24 PM , Rating: 2
Who needs brains when you have money?? LOL..


RE: surpiise
By Eris23007 on 4/18/2007 6:25:07 PM , Rating: 3
Only the people who want to keep having money for a long time!


RE: surpiise
By jconan on 4/19/2007 1:17:54 AM , Rating: 2
Kirk Kerkorian and Warren Buffet come to mind as people who have tons and tons of greenbacks. They drive common cars not extravagant cars to live comfortably. They're contrary to the statement of people with money and no brains.


RE: surpiise
By mrteddyears on 4/19/2007 5:12:32 AM , Rating: 2
Then why have all that cash to give to the tax man when you die, take the ENZO and go off roading across sand dunes.

WHO CARES THEY ARE RICH !!!!


RE: surpiise
By Hoser McMoose on 4/18/2007 3:34:10 PM , Rating: 2
As you say, it's probably not such an issue with this model. Let's not forget that this is a convertible as well! As someone who lives in a climate that occasionally sees temperatures bellow -30C, let me tell you, you don't see too many soft-tops around on those days! Even with the top up it's just not a very viable option!

However this is definitely something to consider if/when we start looking into other electric or plug-in hybrid vehicles. Eventually the idea is to make them true replacements for standard ICE based cars. If they aren't going to work properly at -40C then they just aren't going to sell in this neck of the woods at least. It might only get that cold one or two nights of the year, but those are the times you REALLY want your car to be working if you have to leave the house at all!


RE: surpiise
By Chernobyl68 on 4/18/2007 3:50:44 PM , Rating: 2
ever been to lake tahoe?


RE: surpiise
By othercents on 4/18/2007 5:02:34 PM , Rating: 3
I am very surprised at the number of electric vehicles that are at the auto shows that wouldn't ever be able to run in the snow. These three wheeled inventions that run on motorcycle tires just won't cut it no matter how good the MPG is.

The majority of people (myself included) have one vehicle to run both summer and winter. We need vehicles that will work in all types of weather. My Altima barely made it through the Colorado snow storms which makes me think I should have purchased another truck.

Other


RE: surpiise
By Hoser McMoose on 4/19/2007 12:02:00 PM , Rating: 2
By far the biggest factor in driving in snow is the tires. Everything else to do with the car is secondary. I drive an Altima as well, and with a good set of winter tires it'll handle driving in the snow better than most any truck with summer tires. Actually a rear-wheel drive truck without winter tires is about the worst possible vehicle you can get for driving on snow and ice (all the weight up front + all the power in the rear = no traction). A 4WD truck with winter tires will handle just about anything.

Of course, if the vehicle won't even start in the winter because the motor or batteries won't work in the cold weather, then that's another story altogether!


RE: surpiise
By othercents on 4/20/2007 6:11:25 PM , Rating: 2
BTW. Before my Altima I drove an RWD F150 and did great in the snow even without winter tires. However I did use all terrain tires and I had a manual transmission. My old T-bird was way worse than my Truck ever was.

The problem with the Altima is clearance. I couldn't get in or out of the back streets because the snow was too high. There is also problems on ice with the Altima that I never had with the truck. The truck I can spin the tires and still steer, but the Altima I basically had to keep the tires from spinning just to get it to steer right.

Other


RE: surpiise
By theapparition on 4/18/2007 12:11:54 PM , Rating: 2
My only comment to that, not making any judgement on the actual battery technology, is that no one if going to take out their 50K Lotus out in the snow, so its a safe assumption that this 100K Lotus "knock-off" will not see snow either.

If memory serves, the EV1 used conventional lead-acid batteries, quite a bit different than Lithium-ion.


RE: surpiise
By Polynikes on 4/18/2007 3:10:27 PM , Rating: 2
It may be a "knock-off," but it can get to 60 faster than the Elise. :) I'd wager the Elise handles better, though.


RE: surpiise
By Milliamp on 4/18/2007 3:19:56 PM , Rating: 2
And with a 200 mile range who is going to plan to charge it at 195 miles?

Just like how I usually fill up my car and motorcycle with 30 - 40 miles still left on the tank, I suspect the same will apply for the Tesla.

I am sure the power of the car is reduced as the battery starts to die also, unlike with gasoline.

This means that even new most people will have to charge these at 160 miles or so.

More frequent recharges = lower battery life.

I wonder if they are going to reduce the selling price 20% to match?


RE: surpiise
By Hoser McMoose on 4/18/2007 3:53:37 PM , Rating: 3
quote:
I am sure the power of the car is reduced as the battery starts to die also, unlike with gasoline.

The 'power', in terms of how fast it can go, shouldn't be affected much at all. However the amount of charge it holds (ie how far you can drive) will definitely drop in time.

Another problem with this is going to be leaving your car for long periods of time. Li-Ion batteries self-discharge at about 5-10% per month. So for people who want to store this car over the winter it'll probably be half dead in the spring, so some precautions are necessary here. Mind you, it's not a very smart idea to store a ICE car over the winter with a tank full of gas either.

I can't help but think that we need at least one more major advancement in battery technology before electric and even plug-in hybrid cars are going to be really viable solutions for the mainstream.


RE: surpiise
By othercents on 4/18/2007 5:11:16 PM , Rating: 2
Actually as the battery hits the end of it's charge state the voltage starts to drop. The reverse is true too where fully charged batteries have a voltage spike. However Telsa might have taken this into account and will shut the car down after the voltage goes under a certain number and a regulator that keeps the voltage from going above a certain number.

The regulator is important because sometimes a battery can loose all power under load, but still be charged enough to do some things. For example, if you hotrod the car you might loose power, but if you drive conservatively you might make it home.

Other


RE: surpiise