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Tesla’s promises don’t compute with current physics and economics of batteries

bloomberg.com

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Re: Tesla’s promises don’t compute with current physics and economics of batteries

#11

Post by itchyjunk »

shobith wrote: post #7
itchyjunk wrote: post #5

Although it is very good to be skeptical, it makes the article less valuable than it could have been. 'Musk claimed X and people we talked to said they don't know how it's possible.' I am not saying that the people they consulted didn't know how, but using just that for the entire article was unnecessary. They also claim battery density is increasing by Y% and maybe Tesla is banking on that. Well those density increa…

They could have easily added a few more people speaking while they were at it: https://asia.nikkei.com/Tech-Science/Tech/New-battery-techno...

Very good supplement information. I didn't realize Li ion batteries were so close to their theoretical limit.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#12

Post by mtgx »

mirimir wrote: post #3

It's an informative article, but the title is inaccurate. Tesla seems to be relying on plausible extrapolations for batteries in ~2020.

Bingo. Not only that, but they may even rely on battery extrapolations for 2022, despite the truck and car being launched in 2019-2020. All they need is to break-even in the first year or two, and then they can make-up the profits from the improvement in battery prices. That said, the roadster itself will likely be profitable from day one. It's the truck that may not be.

This is why Musk keeps getting ahead of everyone else and leaves carmakers and media writers in "shock and awe" - because he keeps thinking outside of the box, while they keep thinking within the existing or past constraints.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#13

Post by _ea1k »

Hypx wrote: post #10
melling wrote: post #6

Earlier quoted context omitted.

“Every time the global supply of batteries doubled, prices drop 19%” “Every year the energy density of batteries increases by about 7.5%” So, in 10 years electric cars will double their range, which should be more than enough for most people.

We should be careful with apply Moore's Law style of thinking when it comes to battery innovation. These things can and will hit hard limits at some point. Real progress can be much slower and much less predictable than in the semiconductor industry.

The funny thing is that it really hasn't been that much less predictable. Progress has been slow but steady and Tesla's business model has been built around largely predictable technological progress.

7.5%/year is probably an overestimate, though, and you are right that at some point it will hit diminishing returns. Moore's law has too, though, eh?

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#14

Post by _ea1k »

ams6110 wrote: post #9

If this were any other company making such unsubstantiated claims that didn't have any basis in the reality of the underlying technology, they'd be getting roasted here.

I don't really agree. If another company rolled a 200kwh car out of the back of a truck, did a few passes of the stage, gave passengers rides (high speed launches) for a while, and then reported ~60% battery remaining, I think most would believe them.

We would also wonder about making it to production, but Tesla actually has a halfway decent track record at that.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#15

Post by _ea1k »

mcguire wrote: post #8

" Tesla offers free electricity to most of its Model S and Model X customers while paying almost $1 per kilowatt hour to produce it, Morsy said. That amounts to a subsidy of as much as $1,000 per car in 2017. " I realize that most people believe that Tesla and Uber will be able to continue subsidising their operations indefinitely, but it makes me very nervous.

I can't take this author seriously. There is no way that Tesla is paying $1/kw. That is way past the retail rate, and I bet that they are paying much less than the retail rate in many of their markets.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#16

Post by JaggedJax »

mcguire wrote: post #8

" Tesla offers free electricity to most of its Model S and Model X customers while paying almost $1 per kilowatt hour to produce it, Morsy said. That amounts to a subsidy of as much as $1,000 per car in 2017. " I realize that most people believe that Tesla and Uber will be able to continue subsidising their operations indefinitely, but it makes me very nervous.

I am shocked to see this number. It seems insanely high. Is it really possible they pay anywhere near that for electricity?

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#17

Post by flor1s »

mtgx wrote: post #12
mirimir wrote: post #3

It's an informative article, but the title is inaccurate. Tesla seems to be relying on plausible extrapolations for batteries in ~2020.

Bingo. Not only that, but they may even rely on battery extrapolations for 2022, despite the truck and car being launched in 2019-2020. All they need is to break-even in the first year or two, and then they can make-up the profits from the improvement in battery prices. That said, the roadster itself will likely be profitable from day one. It's the truck that may not be. This is why Musk keeps getting ahead of everyo…

Meh, I think other companies just don't have the bravoure a man like Musk has. Also it helps if your company is a start-up and no heads will roll if you don't make a profit. Established companies don't have that luxury.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#18

Post by _ea1k »

itchyjunk wrote: post #5

Although it is very good to be skeptical, it makes the article less valuable than it could have been. 'Musk claimed X and people we talked to said they don't know how it's possible.' I am not saying that the people they consulted didn't know how, but using just that for the entire article was unnecessary. They also claim battery density is increasing by Y% and maybe Tesla is banking on that. Well those density increa…

While I see some crazy talk in that article, I'm actually pleased with the idea of getting the point across that this requires technical advances.

So many people just nonchalantaly act like they just tossed a few more 18650s in there that it is nice to see someone point out how improbable that is. I'm really looking forward to hearing how this is actually happening.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#19

Post by watchdogtimer »

> To meet Tesla’s claim of 400 miles in 30 minutes for a semi carrying 80,000 pounds would require its new Megachargers to achieve output of more than 1200 kW

1200 kw is a lot of power. That's the average amount of power used by 600 homes, or half of the output of a large wind turbine here in the Midwest, to charge a single truck.

If they use a 440 V supply to charge it, that'd be over 2700 amps.

Re: Tesla’s promises don’t compute with current physics and economics of batteries

#20

Post by vvanders »

watchdogtimer wrote: post #19

> To meet Tesla’s claim of 400 miles in 30 minutes for a semi carrying 80,000 pounds would require its new Megachargers to achieve output of more than 1200 kW 1200 kw is a lot of power. That's the average amount of power used by 600 homes, or half of the output of a large wind turbine here in the Midwest, to charge a single truck. If they use a 440 V supply to charge it, that'd be over 2700 amps.

Eh, there's 20 120kW stalls in the Centralia Supercharger so while it's a lot I don't think it's crazy-talk.
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