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Those can easily be attributed to the dual motors and the lower weight of a 60/70 pack versus a 85 pack, there is absolutely no need to introduce a better cell chemistry to get there. Unless proven otherwise, it's really a rumor that only has traction on the very special echo chamber that the TMC (investor) forum is.
The German specifications table is interesting:
View attachment 77348
Though there's none of that nonsense about anticipated gas savings, there are two different figures given for the power of each vehicle: their horsepower and their "nominal motor capacity." So the 70D is 334 horsepower (I think our units are different), but has a nominal capacity of 522 horsepower in the motors. Then you have 367 horsepower and 385 potential horsepower for the S85, 428 and 522 for the 85D — and then the P85D confuses the lot by only showing its "nominal motor capacity" and not its listed horsepower.
It's odd how all of that works. Either way, I'm very happy with the 428/522 PS I have coming to me next month.
Haven't we known for a while that some of the configurations were limited by the amount of power the battery could provide? I recall seeing a table (back in the 60/85/P85 days) that suggested the 60 was battery limited (same inverter/motor as the 85), the 85 was inverter limited (same motor as the P85, different inverter), and the P85 was battery limited.
There was an update to the stats last year that showed the S60 and the S85 making the same nominal HP (it went from 300 v. 362 to 370ish for both). Despite that, and despite the lower weight of the S60, the S60 was not listed as having a lower 60 time (and I don't think anyone has ever said that an S60 is faster than an S85).
That all suggests that Tesla went from reporting the "actual" expected HP based on the battery/motor combo to just reporting the theoretical max HP of the motor. Which, of course, is next to useless if the battery doesn't have enough juice to actually hit that theoretical max.
The numbers above support that theory, in my mind--that's why you see larger "nominal motor capacity" numbers, and lower hp numbers.
The thing that's irritating is that we've never seen a "real" number for the P85D. If the P85 really was battery limited, it's quite possible that the "real" number for the P85D is a LOT lower than "700" or "691" hp; it may, in fact, be closer to the 416 hp that Tesla originally quoted for the P85.
Olle
Active Member
If that were the case, the 0 to 60 times would be closer. The P85D clearly has more horses going to the ground.
I know that the electric motors have different characteristics than the ICE vehicles (favouring a lower 0-60 timein the EVs), but you should take a look at this website anyway. If you set a dual clutch configuration and enter in the data from the P85D & P85, the 0-60 numbers are not too far off.
0-60 mph Calculator for Cars
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Olle
Active Member
There is a real number for P85D: 413 hp. See dyno test here
http://www.dragtimes.com/blog/tesla-model-s-p85d-shocks-the-dyno-with-864-ft-lbs-of-torque
So you are probably right, it is battery limited. (depending on what you mean by battery limited, there is a lot more power available if you connected the battery to a lower resistance)
For P85 there are multiple dyno stats available, a quick google search gives something like 360 to 460 hp from different tests. Probably varying with SOC, dyno calibration and other factors
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Stop citing that dyno test. It came from a dyno not capable of handling an AWD car with independent motors. As such it only captured the rear wheels.
Olle
Active Member
I haven't cited it before, but what is the correct power then?
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I haven't cited it before, but what is the correct power then?
The 60 has 14 "modules" rather than 16. As each "full module" is 444 cells (6 groups in series of 74 parallel cells ), that's 888 less cells.
In addition the 14 remaining modules appear to have 10 less cells per parallel group. That's 60 less cells per module, for a total of 60x14=840 additional fewer cells.
This is a total of 1,728 fewer cells in a 60kwh pack than an 85. Thus, while an 85 has 7,104 cells, a 60 appears to have 5,376 cells. Doing the math that renders a ~64kwh pack... so there may be some variability in how they rate/operate the pack.
HankLloydRight
No Roads
Not necessarily; not if the big issue with the P85 is traction limits, particularly at launch. And that's where the P85D really distinguishes itself.
Not to be all tin-foil hattish about this, but why does the German site break out actual v. theoretical power for every configuration *other than* the P85D? I honestly don't know the answer to that question.
dhanson865
Well-Known Member
Elon has stated in conference calls and lectures (univeristy, TedX style stuff, you can find it on youtube).
He has been saying for years now that they would use a larger cell size as soon as they get the volume of cars up enough to have control over their own manufacturing or at least be a big enough customer to ask their supplier to use the new format.
TomServo
Active Member
I agree. Tesla does not need to resort to "fuzzy" math or "Voodoo" economics to sell cars. IMHO it insults potential buyers.
The situation is clearly not a simple one. But in fairness, companies play games with ICE HP ratings as well. Do they use HP at the flywheel? Do the consider other parasitic losses? There are more losses between the flywheel and the rubber in an ICE than there is between the motor output shaft and the rubber in a Tesla.
The P85D performs right up there with any 600-700 HP AWD car. I wouldn't mind knowing what the real output on a dyno is, but it's pretty much just academic. The numbers are high and the car performs appropriately for the numbers. Nobody who sits in it for a 3.2/3.1 second run is going to think that 691 is an inflated number.
HankLloydRight
No Roads
Olle
Active Member
the 0-60 calculator is based on evidence with gas cars. As we all know gas cars are outrageously inefficient compared to electrics.
Look at this : (2238kg*(60mph*0.447)sq)/2/3.1s=257kW So P85D uses an average of 257kW during its acelleration to 60mph. The peak power is of course higher at some point. Can some math savvy person tell us based on the acceleration curve what that power is? That would be the answer to the lingering question.
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Bighorn
Top Supercharger
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