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Roadster 3.0

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No production Roadster is 2.4 Ah.

Has that been officially sourced anywhere?

We KNOW the Roadsters 56kW pack is comprised of 6,831 cells. That's 56,000W / 6831 = 8.2W per cell.

With a nominal voltage of 3.7v, that's 8.2W / 3.7v = 2.2Ah per cell. Even if they used a nominal voltage of 3.6v, that's still only 2.3Ah per cell.

In either case, specifying cells with 31% greater capacity gives you only 2.9 or 3.0 Ah per cell for the new roadster pack. Neither are of the capacity of the Model S cells.
 
So going back to the old efficiency and range graphs, allowing for better aero and rolling resistance we're still looking at speeds under 45 mph for this trip.

The source of 2.4Ah cells was Martin Eberhard. We've been around this many times in the last 6 years.

GSP said:
It looks like the Roadster is using 2400 mAh cells. From Martin Eberhard's blog, in respone to a 17Dec2008 comment by dpeilow:

Martin sez:

Yes, I don’t know where this 2200 mAh number came from. True, in the early days of Tesla, this was state of the art. But my car is built with 2400 mAh cells, and 2600 mAh cells are the jellybean cells today. As you say, higher-capacity cells are already on the market.

Tesla Founders Blog (http://www.teslafounders.com/)
 
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Over thinking it, but:

We have identified a new cell that has 31% more energy than the original Roadster cell.

The original cell was a 2.2 ah cell, maybe that's what they are comparing it to? And that wording is odd, We have identified a new cell, haven't they been using it all along in the Model S? Is the "new cell" just slightly lower yields of S cells?
 
Can't imagine the logic behind doing a run at significantly less than the speed limit and making it a public event. I would be shocked if that was their plan. If real range at normal speeds was only like 340 miles, they would demonstrate that somewhere else instead of limping a performance vehicle through a slightly longer route. My prediction is that the 3.0 will make the drive near the speed limits.
 
If it's the new BF cell with the silicon anode then it has higher power output and less weight than the B version. Maybe that is what they have "identified" and it is needed for the Roadster.

https://www.akkuteile.de/tpl/download/NCR-18650BF.pdf
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Can't imagine the logic behind doing a run at significantly less than the speed limit and making it a public event. I would be shocked if that was their plan. If real range at normal speeds was only like 340 miles, they would demonstrate that somewhere else instead of limping a performance vehicle through a slightly longer route. My prediction is that the 3.0 will make the drive near the speed limits.

Impossible if they need to hit ~180 Wh/mile. It will be limping. At least on Highway 1 it will be closer to normal speed.

Elon's backed himself into a corner with the SF to LA claim.
 
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Not sure why you think they'd us a Samsung cell when they can get better cells from Panasonic, plus the fact that the cell you specify doesn't meet the posted specs from Tesla.

Tesla also gets its cells from Samsung. The posted specs is 70kWh. 6831cells x 2.85ah x 3.6V = 70kWh. As for aggressiveness with thermal management, maybe that was the wrong word, a better word is responsiveness.
 
The source of 2.4Ah cells was Martin Eberhard. We've been around this many times in the last 6 years.

Well, forgive me for not having been around 6 years ago. And that blog page no longer exists.

So how is it the Roadster has a 56kW pack, yet at nominal 3.6v using 2.4Ah cells = 59kW, and 2.6Ah cells =64kW?

If the voltage is a nominal 3.7v you get either a 61kW or a 66kW pack.

How do the numbers jive for those cell capacities?
 
Disclaimer - I am not a Roadster owner. Having said that I don't understand the lure of more range with respect this specific car. Looking at the purpose and function of the Roadster, isn't performance the desired attribute? Can one (or would one want to) even sit in the roadster for 5-6 hours nonstop between LA-SF? To me it feels like Tesla is doing a magic trick - distracting with the 400mi talk - while behind the scenes/quietly working on the performance (i.e. acceleration) figures. Is it unreasonable to expect that 3.0 will have awesome/super car 0-60 #s with the new pack and that's the real news?
 
Well, forgive me for not having been around 6 years ago. And that blog page no longer exists.

So how is it the Roadster has a 56kW pack, yet at nominal 3.6v using 2.4Ah cells = 59kW, and 2.6Ah cells =64kW?

If the voltage is a nominal 3.7v you get either a 61kW or a 66kW pack.

How do the numbers jive for those cell capacities?

It's been repeated a few times since and I'm not having a go at you, but it is a pity the same things resurface.

There was much speculation back then that the capacity increased to 59 kWh but usable remained at 53.