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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."
With a title like that, you know the article is going to be good for a laugh. Sort of like people who say "physics says..." who wouldn't even recognize the formulae that apply to the problem in question if you wrote them out in front of them.
1) Passengers in the Roadster noted how high its floor is. Aka: it's a double-high pack. Tesla already makes 100kWh packs for the S and X that are single-high. They may need to extend a bit further forward and back because the Roadster is a bit smaller of a footprint (on S and X they only slightly overlap the wheelbase, and on Model 3 they're inside the wheelbase entirely), but there's nothing at all implausible about 200kWh in such a form factor.
2) The megacharger charge port has been filmed by KMan. It has 8 giant pins in what appear to be a 2x4 arrangement, with ground and control pins likely clustered in a side slot on the right. These pins are much larger than those on the supercharger port, and there's a lot more of them. Also note the 2x4 arrangement: there appear to be four separate battery packs, and there 4 separate drive units. It appears that bloody everything on this vehicle is redundant (one assumes that there's at least a charge balancing system between the packs).
3) The means to provide the power to the megachargers is very, very simple: they're battery buffered. Tesla has always been clear on this; they're not drawing that power straight from the grid. More to the point, Semi uses the same battery chemistry as Tesla's grid-battery buffers (NMC). It's an extremely durable chemistry.
4) The article is very reasonable in its assessment of the battery capacity on the 500mi semi - they say 600-1000kWh (I've been working on the assumption of 900kWh, but it could be a bit less). Their estimate on the price, however, assumes that batteries cost $100-$170/kWh retail. Yet the raw material costs for said cells is only about $50/kWh - and that's currently at "spiked" prices which can be expected to drop as the mining industry readjusts to the new demand curve (historic prices would be more like $35/kWh). The whole point of the Gigafactory was to make li-ion batteries - finally - get closer to the cost of the raw materials that go into them. These numbers simply suggest that the Gigafactory has done exactly what it was designed to do.
5) Their estimate of the weight of the battery pack is probably correct (around 5 tonnes). However, in addition to the weight savings from using electric drive units vs. a big diesel / transmission / pollution controls / etc, Tesla always builds light. Don't expect the primary structure to be made of mild steel on this one; expect UHS steel, with 4-5 times the tensile strength, for example. Guillen stated in Europe that it has the same payload capacity as a diesel semi (aka, the tractor is no heavier), and that's probably correct.
Or, to put it another way: none of the "experts" expected the Model 3 SR to come in at almost exactly the same weight as the BMW 330i, with the same performance, more standard features, and a cheaper price. It did. And the LR isn't much heavier than a 330i, and well faster (can't wait to see the specs on the performance package!)
6) Charge rates of 7 cents per kWh: First off, their estimate that charging should cost 40 cents per kWh is just absurd. Pure nonsense. Even Tesla's current generation of superchargers is half that ($0,20/kWh), and they have to pay demand charges. That said, 7 cents per kWh comes across as extremely ambitious... until you start looking into it. And then you realize how much of a game changer it is that Tesla is doing here.
We gotta go to a crappy town where I'm a hero.
NMC li-ion, likely 2170 form factor, 4x packs. Hard to estimate the number of bricks (because we don't know the voltage) and thus the number of cells per brick.
The charge times are perfectly normal for Tesla cells. 30 minutes to 80% is the standard for supercharging as well. It's just more cells and more power.
We gotta go to a crappy town where I'm a hero.
Meanwhile, spyshots and the VIN count on Model 3 show production greatly accelerating.
As for "exaggerating everything" - you mean like promising a battery within 100 days of signing a contract, and delivering it in 55? Promising the Model 3 with 215 mile range, then delivering it with 220, with an option for 310 - a number that's in turn downrated from EPA testing of 334 miles? What exaggerations about vehicle stats and pricing are you thinking of exactly?
We gotta go to a crappy town where I'm a hero.
Yep, trolleybuses and electrified trains work fine in cold, snowy, rainy climates like Boston, Seattle, or parts of Eastern Europe and China.
No, idiot.
Wheel torque = engine torque multiplied by overall drive ratio (minus losses). Since the overall drive ratio is typically between 3 and 5 in top gear (and much higher in lower gears), wheel torques are going to be at least 3 times engine torque and possibly more than 20x engine torque (in low gear).
That makes it much more comparable, and not an exaggeration.
The real "Libtards" are the Libertarians!
I don't totally disagree with this, but in fairness you should know the Japanese government very heavily subsidized research at both Toyota and Honda into hybrid engines.
With that said, it was clearly n wise economic exercise.
They're going to be giant truck stops, covered, with solar panels and wind turbines. The same batteries buffer the power generation as buffer the high speed charging, so two for one.
They can just run all the charging, and lease out the retail part to the current truck stop service companies.
"The first Toyota Prius model starting being sold in 2003 - long before Musk had even heard of Tesla"
Fuck, how did you manage to stuff so much wrong info into so few words? The Prius first went on sale in Japan in 1997 and internationally in 2000; Eberhard & Tarpenning founded Tesla in July 2003 with Musk becoming Chairman in April 2004 & helping to securing financing while also investing millions of his own money.
"That Prius electric technology is so successful it is now integrated into many of Toyota's lines. More importantly, those lines are actually profitable, and aren't over priced, overly limited vehicles, that suck up govt tax payer money to manufacture"
Sure but that Prius tech did fuck all to get anyone excited about EVs or to goad the industry to get off their asses & build electric vehicles that people covet. Those lines are only profitable because Toyota already have profitable cars to offset the losses of the early years. It took them 5 years to get to ~120k sold in the USA which Tesla surpassed in roughly the same amount of time - for a car that cost THREE to FIVE times as much.
Hell, the electric underpinnings barely changed for 10 years, the battery remained the same size & power for about as long and it took a dozen years for them to figure out a larger battery and that it might be a good idea to attach a power cord.
Pain is merely failure leaving the body
EVs are cleaner than fossil fuel vehicles even in parts of the grid where coal dominates.
We gotta go to a crappy town where I'm a hero.
In the past 8 years Tesla gross revenue has increased by a factor of 400. This is not a software business they can just make new cars appear out of thin air with a license key. They have to add factory space, but tools, hire tons of people and of course, buy a lot more parts and raw materials to make more cars.
Expanding a business like Tesla is a HUGELY capital intensive prospect. It's going to be a money loser until they grow to a size where growth starts to flatten out and scale starts to dominate. Don't confuse losses due to capital investment in facilities with per-unit manufacturing losses. At some point, they will reach a tipping point and their capital requirements will flatten out and their profits will be so big they'll make a grown man cry.
The trick is to stay in business long enough to reach that tipping point. And for that aspect of the business, having a front man like musk who can dazzle the masses like PT Barnum is a very good thing indeed. I predict in 10 years time the idea that "Tesla will never turn a profit" will be laughable.
I've been waiting 5+ months for Tesla to fulfill an order for a Powerwall2. No ETA on the delivery. Plenty of excuses that don't really explain why. So there is a lot of Hype from Tesla/Musk but can they really deliver? Forget about battery technology of the future if they can't meet the demands of today.