Uhh, yeah. You know what 480kW at 0 RPM looks like? Infinite torque. When you understand what power and torque means, you understand the taper.
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Uhh, yeah. You know what 480kW at 0 RPM looks like? Infinite torque. When you understand what power and torque means, you understand the taper.
For some reason I was thinking that the heat of driving would hurt performance more, not the battery part, but maybe motors... I don't know. I should record 0-60 when it is hotter out.
I just compared the video I did the other day, to the one I did last night. Right now I don't have a good way to do it frame by frame, but trimming them down to where the bar moves and the first frame I see "60", the video from the other night at 236 rated range is 0.1s faster than last night at 267 rated. The car was warmer the other night because I had been driving around, but when I did the test last night it had sat for about 1.5hrs.
So I'll try to do it during the day, after driving for a bit, with 100% SOC.
The other night was also a worse place to test because the road wasn't entirely straight or flat, which is why I consider it flawed.
I have used a different method: I counted the frames of the video by going frame by frame in VLC video player.
The length of each frame is 33,20ms (VLC shows 30,125 Hz video codec) - so basicly three frames are a tenth of a second. I assumed that rollout would get the car to 5 mph before the time measuring starts (even though I am not sure if this is correct, because it makes an awful lot of a difference).
This is what I ended up with:
0-60 mph: 3.29s (99 frames, error margin +/- 0.03s)
5-60 mph: 2.82s (85 frames, error margin +/- 0.03s, with rollout)
0-100 kph: 3.50s (105 frames, error margin +/- 0.03s)
8-100 kph: 3.02s (91 frames, error margin +/- 0.03s, with rollout)
Also, don't forget power/weight and acceleration. Best times are likely to be had with a very lightweight lone driver. These joy rides with heavy passengers are likely to slow the car down somewhat.
( At some point real drivers are going to feel disadvantaged when they drag-race against an empty car running on autopilot. :redface: )
( At some point real drivers are going to feel disadvantaged when they drag-race against an empty car running on autopilot. :redface: )
LargeHamCollider
Battery cells != scalable
I suspect this is the case, tapers look identical, huge thanks for all the data Pete!
I'm about 215. Maybe Tesla does the test drives with 100lb drivers.
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I suspect this is the case, tapers look identical, huge thanks for all the data Pete!
You're very welcome. I'm glad it has been helpful.
well.... You could theoretically dump 480kW into the motor at 0 rpm, and it will produce a-lot of torque, but not infinite. The losses will be in I^2*R heating losses of the coils.
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While heat is not good for the motor and inverter due to higher I^2*R losses (because R goes up a little), the battery is by far the limiting factor.
My testing showed a 50% or more drop in cell impedance at higher temperature. At 20 amps per cell, the batteries are by far the biggest loss of power/energy due to their impedance.
Furthermore, a hotter motor won't have such a significant increase in impedance.
We're talking ~45°C - 50°C which would be the max Tesla would heat the cells too. On the other hand, 50°C would barely be operating temperature for the motor windings. Same with the inverter. The inverter igbts are probably spec'd to 150°C, while 150°C would destroy the cells immediately.
What is your recommendation for getting the car to the right temp and having a full charge? Drive hard for a while in warm weather, SC, drive hard for a bit, but try to keep >95% SOC?
Clearly the comment of facetious since infinite torque is impossible, there will always be other limitations. The point was expecting full power earlier is just a misunderstanding of the difference between power and force. The ramp cannot be avoided.
This is probably right. For any given SOC, the 90 seems to be charging quite a bit slower than the 85.
CleanPower
Member
What the data shows is that the 90D is charging at between 3 and 11 kW lower power for the first 30 to 40 minutes on the Supercharger.
(Other than the 5 minute glitch where KMan's charger lowered its power output.)
This is a concern because the optimum Supercharging sessions for long road trips are about 30 to 40 minutes or less.
So it looks like the 90D is going to take longer to charge on road trips than the 85D - unless the Superchargers haven't been programmed for the 90D yet...
The 90D charges at lower power than the 85D for the first 60 minutes on the Supercharger, but at a slightly higher power setting (about 2 to 5 kW higher) than the 85D after that.
Panoz
Member
@Cleanpower: great graph, but can it be modified to show time? How much longer does a 90kw battery take to charge than an 85kw? Does a typical 30 minute charge go to 50 minutes?
ArtInCT
Always Learning
Pete:
I do have yet another question for you... this question is regarding the MAX BATTERY POWER setting...
Let us say you have the MAP high and the ENERGY GRAPH low on the 17" display... as a "normal" display setup.
How many 17" display touches or interactions does it take you to get to the screen with the MAX BATTERY POWER and then invoke that function?
Also, can that function be promoted to either of the two steering wheel thumbwheels??
Again, thanks for being SO NICE with your quick replies and help. I feel you have really been very supportive to TMC'ers who are P90D focused.
Art
I do have yet another question for you... this question is regarding the MAX BATTERY POWER setting...
Let us say you have the MAP high and the ENERGY GRAPH low on the 17" display... as a "normal" display setup.
How many 17" display touches or interactions does it take you to get to the screen with the MAX BATTERY POWER and then invoke that function?
Also, can that function be promoted to either of the two steering wheel thumbwheels??
Again, thanks for being SO NICE with your quick replies and help. I feel you have really been very supportive to TMC'ers who are P90D focused.
Art
Controls -> Driving -> Max Power text -> turn on -> close button -> wait...
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Can you post a image of the P90D battery sticker or just the part number?
If you can tell me where the sticker is I can
ArtInCT
Always Learning
The battery part number is just behind the passenger front wheel under the car and on the side of the main traction battery pack (outward facing).
There are two stickers there... from what I have seen on a 90D.
Thanks Pete90D.
There are two stickers there... from what I have seen on a 90D.
Thanks Pete90D.
I also wanted to follow up about the blurry vision people reported. Everyone is different so I won't say it isn't going to happen to people, but I haven't had any blurry vision or headaches. I think the first couple times I drove a P85D it was a bit of a shock and I felt different, but nothing like that in the P90D.
I will say though that the 2nd day of owning it, my neck was a little sore from random hard acceleration. I experienced this after a number of launches in a P85D and just got used to launching without my head against the seat and was fine. I think I wasn't prepared for having the extra intensity in the 30-60 range where it is less likely I'd be "prepared" with my head back or tensing up to prep for a launch.
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I'm also trying to arrange for various high speed tests in a place where lots of video can be taken and I can push limits more. A few tests I want to try
0-155
0-120
30-90
30-120
60-90
60-120
90-120
I will say though that the 2nd day of owning it, my neck was a little sore from random hard acceleration. I experienced this after a number of launches in a P85D and just got used to launching without my head against the seat and was fine. I think I wasn't prepared for having the extra intensity in the 30-60 range where it is less likely I'd be "prepared" with my head back or tensing up to prep for a launch.
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I'm also trying to arrange for various high speed tests in a place where lots of video can be taken and I can push limits more. A few tests I want to try
0-155
0-120
30-90
30-120
60-90
60-120
90-120
Superchargers are essentially dumb devices. The car controls how much power it draws, so any change to the programming will be on the car side of the equation.
