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Battery weight

Just curious. A number of friends have played devils advocate concerning the added weight the battery must have. What's the weight of the engine for a 5 series or an A6?

Well, 2015-2020 is still a broad range, and there has been no shortage of future battery tech announcements in the last few years. Let's just watch and see what happens...

Weight has gone up, but Cd has gone down. A lot.

I think we need to wait for numbers appear here in website before we can get any clear answers to weight, Cd etc.

As much as I trust Elon, he is not the engineer behind stuff, he is enthusiastic leader, visionaire and investor with some clue about stuff that people in Tesla tell him. I would trust JB Straubel or Peter Rawlinson more than I trust Elon for accurate numbers.

There is no 80%, just that it can be charged in 45 minutes.

If Model S only gets 300 miles on a forced full charge that is not recommended, then it is half false advertising to say it has that range. (Nicu)

In a recent interview, Musk claims Tesla's technology can charge at "100 miles every 20 minutes". Note that he does not say 300 mph although that would be mathematically equivalent. One possible reason might be that he wants to avoid the impression that the 300 mile battery can be charged to the max in 60 minutes. 100 mi/20 min equals 225 mi/45 min, which is pretty close to 80% of 300 mi (240 mi). The last 20% may take considerably longer than another 15 minutes.
http://www.sfgate.com/cgi-bin/article.cgi?f=/g/a/2011/10/26/businessinsi...

Note that I am really just guessing here, trying to fit some puzzle pieces together, but I am still waiting for some official/public confirmation of my assumptions.

Regarding the 80%/45 min fast charge issue, here is another puzzle piece:

Tesla claims that the Supercharger would take any Model S from a 10 percent to a 90 percent charge in 45 minutes, but Mr. Straubel said in an e-mail that the company would prefer to focus on "recovering more than a 50 percent state of charge in 30 minutes of charging, or 150 miles of driving range in 30 minutes with the 300-mile-range vehicle."
http://wheels.blogs.nytimes.com/2011/10/26/bucking-trends-tesla-goes-it-...

Straubel's 150 mi per 30 min conspicuously matches the 100 mi per 20 min mentioned by Musk in the BI interview (link in previous post). And again, Straubel carefully avoids saying anything that would sound like 300 mi per 60 min.

And also avoids saying why he focuses on the 50% in 30 minutes deal. Of course it's probably to limit damage to the batteries.

Another interesting, subtle difference between Musk's and Straubel's comments: Musk describes the charge speed in miles-per-charging-hour, whereas Straubel talks about "percent state of charge." Does this imply that quick-charging a 160-mile battery for 30 minutes adds only 80 miles?

That's the implication. I'm sure the manual will go into a lot more detail. I'm also sure the computer will be programmed to charge while protecting the battery as much as possible and that you would need to put it in range mode to charge up to the full 100%. Yet another reason to buy more battery than you need.

If your commute is 80 miles or less with the occasional 20 mile side-trip, then the 160 mile range would be perfect. But if you would fairly regularly drive 120+ miles, then you'd likely want to spend the $10k on the larger battery.

Do some numbers people, do some numbers!
Even if the type of batteries described were available, you run into the inconvenient issue of a power source capable of charging the battery, Assuming 3 miles/kWh, 150 mile range requires 50 kWh of energy. To collect this in 30 minutes requires a charge rate of 100 kW. Where outside of an industrial location are you going to find that size of a power terminal? I think that the 3 or 4 neighbors that share your 50kW secondary transformer from the power utility will not be too pleased if you're trying to suck up 100 kW for half an hour.

Zelaza, we're not talking about home charging. :-p

My internet access used to be 56 *kilo* bits per second (and that was the faster of the available modems). What do I have at may home today? I do not even know, actually, b/c it's good enough that I don't care. Looked it up, it's 16 *mega* bits per second. Agreed, there is a qualitative difference between kilo bits and kilo watts, but the infrastructure will be growing with the job.

@Mycroft:
You're right. Moments after pressing the SEND button I realized that this charging was, probably, not intended for home use. My bad :-(

@Volker.Berlin:
There really is more than a qualitative difference between bits and watts. While we encourage the consumption (utilization) of bits, one of the premier reasons for converting to EVs is to reduce world energy consumption. Increasing the electrical energy available, and encouraging its consumption, is probably not the way to go.

@Zelaza, I beg to differ. An efficient and capable grid has nothing to do with increasing the electrical energy available. There is enough electrical energy available, anyway. An extension of the grid is desperately needed (just as well in the USA as in Europe, I guess) to use the available electrical energy efficiently, and make it available where it is needed. Particularly the desirable switch to renewable energy sources requires a capable grid as a prerequisite. Well, there are other threads already in this forum that discuss the different ways of producing electricity, and their very different characteristics. Suffice to say, improving on the grid can only do good and does not mean increased energy consumption. Quite to the contrary, actually.

About miles vs. %, I suspect Straubel is being more technical, since miles/kwh depends on driving conditions and habits. 150 mi. at 100 mph. on the Autobahn is different from 150 mi. at 70 mph. on a US freeway.
@Timo;
As much as I trust Elon, he is not the engineer behind stuff, he is enthusiastic leader, visionaire and investor with some clue about stuff that people in Tesla tell him. I would trust JB Straubel or Peter Rawlinson more than I trust Elon for accurate numbers.
I wouldn't bet 5¢ on that, if I were you. Elon is stuck in up to his eyeballs on the tech, and probably makes all the go/no go decisions on such things--not to mention pushing the envelope everywhere. He IS an engineer, and a brilliant one.

Just to continue the above, his mother mentioned that from a young age he had eidetic memory, and could recall exactly whatever he'd read. Whenever anyone wanted to know anything, his sisters used to say, "Ask Genius-Boy." If he'd read it, he knew it.

When asked how he learned "rocket science" to start SpaceX, he said, "I read a lot." It took him a couple of months to get to the boundaries of what's known.

Still, he is not the engineer behind the stuff. Elon just can't know everything, just what those engineers tell him, so anything coming from Elon is second hand knowledge unless it is some decided number which is a goal he had set that can't fail.

You're wrong Timo. As an example, he figured why one of the most important rocket launch failed at SpaceX. Without that, the company would have probably failed. Only someone who knows very close to everything about the rocket could do that.

" When asked how he learned "rocket science" to start SpaceX, he said, "I read a lot." It took him a couple of months to get to the boundaries of what's known. "

The boundary of anything substantial is only skin deep. You can't possibly be serious with this comment. Perhaps that explains why Musk left graduate school at Stanford after only a couple of days; that's all the time it took for him to learn everything they could teach.

" Without that, the company would have probably failed. Only someone who knows very close to everything about the rocket could do that. "

Oh! Pulleeezzze.

You clearly did not have any deep problem to solve ever, nor any Eureka! moment.

I am beginning to think he has a very deep problem...but i don't know that there is a solution.

Zesleza Elon Musk was just awarded for Innovator of the Year, honoured for being the most creative, disruptive, and influential individuals in the world. "Musk was recognized for revolutionizing three of the biggest industries in the world--automobiles. energy and space exploration--simultaneously." To bad Musk "left graduate at Stanford...." Just curious, What grade did you get too?

Nicu The shorts must be gettting nnnervous!

Yes, I watched carefully the situation yesterday. During the first two weeks of October, 13.9% of all traded shares where shorted. During this time, the share price went up 18%. Now it's even higher. Of course I cannot predict if nor when, but I'm pretty sure that if they panic a bit, there will be fireworks !

I agree with Zelaza about Musk. Even if he would be smartest person in the world he still could not know everything about SpaceX rockets. A lot but not everything. He is a head of the staff, not the staff. Just to read through all that is done in a month would require a month without any other activities, at which point he would have another month worth reading from what staff had done during that month. It's just not possible. Not in anything as complex as orbital vehicles or even a BEV. Just plain material testing of nuts and bolts would take days to read thru. Someone has done those tests, but it has not been Musk.

SpaceX and Tesla motors are not some garage projects where one man can know everything that is happening and how things have been done. Musk might have very good knowledge of grand picture and what can be done and what has been done, but he can't know how all of that has been done or how it will be done.

Because of that anything he says is second hand information. Pretty reliable information, because the person that knows the real facts has probably told him those directly, but it still is second hand knowledge.

Knowing "everything" does not mean to know all numbers by heart. But knowing all intermediary problems and decisions that were made as a consequence of that. There are CEOs of much larger companies (think like 100x) that spend 30 min. to choose the shade of gray for the restroom indicator of their stores (not to talk about all other materials).

You forget that science and discovery is still made by the most complex machine ever, the human brain. Software and other tools are just that, another way to get in touch with reality (or to alter it). And while progress in achieved in (small) teams, every atomic idea comes in just one person's mind. I do not think he would lie about that (I have seen the interview, it was in the Bloomberg documentary, I think). He just doesn't need to.

I break my promise by answering to Nicu.

@Nicu, you have lost your touch to reality or you have never worked in a largish company in any kind of leading position. It is impossible to company heads to know what all of their their staff is doing. It is just plain impossible. If you think otherwise you are even more stupid than I thought of, and to my opinion you are already proven to be rather stupid. So try not to be any more idiotic, please.

Now back to ignoring Nicu...

Timo, you obviously haven't met someone who is scary smart.

Denis Vincent wrote:
"Just curious, What grade did you get too?"

Response: All of them. And I mean ALL OF THEM.

Buy the weigh, that should be "Too bad Musk ...."

I am scary smart. Knowledge doesn't indicate smartness and wise versa. There is only 24 hours in a day, you can't use it all just to read reports from your staff. There are smarter things to do with that brain power (no pun intended).

I generally pity people that need to proclaim themselves smart. But, you, Timo, are scarily pathetic and just make me laugh. I bet you work in 20th or even 19th century company and confound intelligence and knowledge with some algorithms for the lemmings employees plus memorizing some Excel tables. You have no idea what a Silicon Valley company is, what it means to think differently or how exceptional some people can be.


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