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Tesla Roadster Update Extends Range
mrflash818 sends word that Tesla Motors has announced an upgrade for their Roadster vehicles that boosts the range from about 240 miles to almost 400. In addition to the battery improvements made since the Roadster launched in 2008, Tesla has a kit to retrofit the body to reduce its drag coefficient from 0.36 to 0.31. They also have new tires, which improve the rolling resistance coefficient by about 20%. They say, "Combining all of these improvements we can achieve a predicted 40-50% improvement on range between the original Roadster and Roadster 3.0. There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles. We will be demonstrating this in the real world during a non-stop drive from San Francisco to Los Angeles in the early weeks of 2015." Tesla stopped producing the Roadster in 2012.
The one update they really should do along with the battery upgrade is add Supercharger support.
But if we conserve energy, the environmentralists win!
Summary: Lots of improvements in a number of areas can make a big, big difference.
Since ~2008 I know they've increased the energy density of their 18650 cells by 20-30%, which would correspond to a 20-30% increase in range no matter what. After that it starts adding up quick.
I wonder if they might end up restarting roadster production. For a small car manufacturer that could even be fairly logical - produce as many as you can for a relatively short period of time(few years), then shut down production for a few years to let the demand recover and grow.
Perhaps more importantly, increasing the range of a car from 250 miles to ~400 also means that you could put a smaller battery pack in that costs nearly half as much, making it more affordable.
It also helps show the longevity of Battery Electronic Vehicles. Though it's only been two years since they stopped producing it, they're still producing not just maintenance parts, but serious upgrades.
I don't read AC A human right
I'm pleased to see them backporting new tech to the older vehicles, and by doing this they also get replacement batteries into vehicles sold as much as 6 years ago (first introduced in 2008), though presumably they've had replacement battery packs available all along.
I'm sure they're also going to be making at least some profit on these upgrade kits, and by not abandoning the older vehicles they probably do a lot to cement loyalty from those same customers who were willing & able to drop more than $100k when they first came out.
fencepost
just a little off
Feels like getting upgrades in a RPG. Pretty awesome.
It's also nice to see actual real world battery density improvements, rather than just hear about it. Of course 31% over 7 years is a lot less than the 7%/year improvement people like to say lithium ion experiences.
While it is obvious that the new batteries will nearly double the range (li batteries double about every 7-8 years), what about the super charger? No doubt the roadster owner should pay for it (which would also include the electricity), but these the guys that helped make Tesla. Without them, tesla NEVER would have gotten off the ground.
Come on, elon. You can do the super charger.
I prefer the "u" in honour as it seems to be missing these days.
I confess, I was not impressed with the practicality of the all-electric concept, and felt it would always be pretty much a rich person's toy. Common in Hollywood and maybe the Silicon Valley and around Wall Street, and maybe Redmond, for bragging rights, but you'd never see one in Omaha.
The two issues as I saw it were range and charge time. (Cost is also a factor, but cost usually goes down over time.) It looks like Tesla is making a good faith effort to tackle the range issue, and there is some effort being made to reduce the charge time. Good for them.
It also occurs to me that for self-sufficiency, all-electric vehicles may be an advantage, as electricity could be easier to make and store than methane, for instance.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
4 years after you bought it, it was up to 500 mile range and getting 50 mpg.
The range increases must partially also translate to the "refill cost" so it's gotten less expensive to drive over time.
Impressed-- range of electric cars was the main challenge factor (until the recent gasoline price drop).
Electric at 12c/kwh runs about 1/4 the cost of gasoline at $3.50 ($3.50/100 miles vs $14/100 miles). My electricity runs 10.3/kwh and houston gasoline is down to $1.99 here (Waxahachi has $1.91 gasoline as of 12/21).
So about $3/100 miles electric and $8/100 miles gasoline right now.
Apparently you do NOT want electric cars in Hawaii (something like 27c/wkh).
It doesn't take many electric cars to kill 1% of oil demand and cut $40 to $50 per barrel off the top price for a barrel of oil.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
"There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles"
42 mph , downhill with a tail wind...
To be fair to Tesla, the driving conditions for their range estimates are actually usually very realistic. I have a 60 kWh Model S, and I match rated range while driving 65 mph in the summer with air conditioning on. It gets significantly worse in winter, and it gets much better in nice 65-70 degree weather days.
Warning: Opinions known to be heavily biased.
>Low rolling resistance tires number one problem has been bad road comfort.
Which surprises me. I fitted low rolling resistance tyres to my bike and experienced improvements in ride comfort, traction, and significantly reduced rolling resistance (tire wear was increased though as these are technically "racing" tyres). When it is your legs powering the vehicle you can really feel all this. On bikes they achieve the improvements with suppler casing (which increases ride comfort) and softer/suppler rubber (which increases traction and ride comfort but decreases tire life).
(And why is it that people assume that low rolling resistance has anything to do with the coefficient of friction and traction?)
Currently Tesla charges at over 250 amps with their superchargers and I charge mine at home at 80 amps. As you say, though, the biggest limitations will be cooling and just getting that much current into the car. I think it's amazing that Tesla is able to handle 120KW through their current connector (and I hear they're experimenting with 150KW). None of the other charging connectors come close to this. They might also need to increase their active cooling of the batteries.
Right now my P85 will draw upwards of 310KW from the battery pack, but only for short bursts when accelerating hard.
Charging this fast might require something similar to their battery swapping, with a large connector built directly in to the battery along with support for the coolant loop where something comes up under the car to charge and actively cool the battery when handling so much current.
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The difference is that I can charge at home overnight to a full battery in my garage and I spend 5 seconds plugging in at night and 5 seconds unplugging in the morning. The beauty of it is that I don't need to go to a filling station except on long trips.
As more and more charging stations go in, most charging will happen at home and/or work where charging time doesn't matter.
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I was surprised by the .36. When Lexus first came out c. 1990 they advertised the LS400 heavily as having a .28 and later models got down to .24. .36 is 50% worse than a 1990's sedan and surprising since range has always been an issue.
I guess it looks cool, though (hard to argue with the company's success).
You're missing the part about where this is a roadster. Convertibles have considerably more drag than cars with roofs. Also, you're only looking at Cd. Cd is used in the drag equation to calculate total drag, and the part that isn't part of Cd is surface area. The lexus vehicles have much higher total drag because they're all much bigger cross-sectionally. The Tesla Roadster is tiny.
"No, no, no. Don't tug on that. You never know what it might be attached to."
It's not just the cabin that needs to be heated. The battery heating system consumes a fair bit of power on very cold days. You'd think they would heat up enough from just being used to power the car, but apparently heating is still necessary and affects range quite a bit.