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Is Elon Musk Greatly Exaggerating Tesla's Battery Technology? (bloomberg.com)
"Tesla's newest promises break the laws of batteries," writes Bloomberg. Long-time Slashdot reader rudy_wayne summarizes their report.
"Elon Musk knows how to make promises. Even by his own standards, the promises made last week while introducing two new Tesla vehicles...are monuments of envelope pushing. To deliver, according to close observers of battery technology, Tesla would have to far exceed what is currently thought possible." The Tesla Semi, which Musk claims can haul 80,000 pounds at highway speeds for 500 miles, then recharge 400 miles of range in 30 minutes, would require "a charging system that's 10 times more powerful than one of the fastest battery-charging networks on the road today -- Tesla's own Superchargers."
The Tesla Roadster is promised to be the quickest production car ever built. But that achievement would mean squeezing into its tiny frame a battery twice as powerful as the largest battery currently available in any electric car. These claims are so far beyond current industry standards for electric vehicles that they would require either advances in battery technology or a new understanding of how batteries are put to use, said Sam Jaffe, battery analyst for Cairn Energy Research in Boulder, Colorado.
But Jaffe reaches an interesting conclusion. "I don't think they're lying. I just think they left something out of the public reveal that would have explained how these numbers work."
The Tesla Roadster is promised to be the quickest production car ever built. But that achievement would mean squeezing into its tiny frame a battery twice as powerful as the largest battery currently available in any electric car. These claims are so far beyond current industry standards for electric vehicles that they would require either advances in battery technology or a new understanding of how batteries are put to use, said Sam Jaffe, battery analyst for Cairn Energy Research in Boulder, Colorado.
But Jaffe reaches an interesting conclusion. "I don't think they're lying. I just think they left something out of the public reveal that would have explained how these numbers work."
He has to do something to keep people investing in his company, and keep the stock price high. Looking at the fundamentals, it's a crazyy buy for the stock. Never turned a profit, losing billions per year, cash-on-hand to keep running until summer next year - and massive commitments for new products and deliveries they have to meet. Add in the track record of never coming close to those delivery numbers - and it's crazy anyone buys the stock. So Musk has to put on the PT Barnum act and drum up more support so they can turn to the last option they have to raise more capital - sell more stock.
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
Oh, one more thing: expect to see things get more impressive with time. For example: a lot of people are expecting the handling to be poor on the Roadster because the battery pack will weigh slightly over a tonne (at current cell energy densities). Sure, Tesla will be going all out to make the rest of the car light, but still, that's a lot of weight underneath you, right?
But there's one thing people are forgetting: torque steering. The rear wheels are each driven by separate motors, each hooked up to wheels with very sticky tires. You can have one side going full thrust forward and the other side going full thrust in reverse if you wanted. You could make the car pirouette in place if you wanted. Computer controlled J turns, precise drift control, etc? They're only limited by their programming; there's a lot more potential here than you can achieve with just differential braking.
And we already know that Tesla is working heavily on torque steering; this isn't something that's going to come as a surprise to them. Torque steering is the principle behind the anti-jackknifing approach on Semi.
We gotta go to a crappy town where I'm a hero.
I'm betting the eight "pins" on the port aren't pins. They are sockets with two contact surfaces.
Eight 120 kWH batteries (five in the 300-mile version) made using the newer 2170 cells wouldn't be much of a stretch of the current technology. This would provide 960 kWH total which is within the range of estimated needs.
Tesla reuses the same AC/DC converter in their superchargers that they use in their vehicles. Current superchargers use 12 of these 11kW AC/DC modules to provide about 130kW (after losses).
If you go with the same theme but update it to use 12 of the 20kW AC/DC modules now used in the model S, the existing supercharger design could be trivially increased to about 216kW after losses.
Eight 216kW superchargers operating simultaneously could deliver 1,728kW - more than enough to provide a 400-mile charge in 30 minutes.
In fact there are several trolleybus lines in Murmansk. That is more to the north than Fairbanks.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
Had both a power cord *AND* an electric only operation mode.
Both those features were removed for USDM models because the Japanese (rightly!) thought Americans were idiots and did their part to idiotproof the vehicles in order to ensure people didn't constantly run the batteries down too low, and because the charger required a dedicated breaker to avoid tripping. I forget it if was 110 or 220 and what current, but it WAS an available option/standard for JDM vehicles.