[updated with *] P85D 691HP should have an asterisk * next to it.. "Up to 691HP"

[Realist]

We had this discussion before :-D

After driving various electric cars I can confirm that none of these vehicles is capable of delivering constant power. This should come not as a surprise for anyone knowing the basics about ohm’s law. Therefore W=V*A. So of course below a certain SoC, power output has to drop. Furthermore Tesla’s electric motos have very high peak power but again constant power is limited. So if you go to track BOTH battery and electric motor will limit their power outputs depending on SoC and/or heat. Adding more coolers has only very limited effect. You will not get that fluid where you want it to be because any kind of fluid is of course electroconductive.

Anyway, of all electric cars on the market today the P85D is by far the best performer overall. The fact alone that people are comparing it with power monsters like a Hellcat or RS7 says everything. I remember people making jokes about the BMW i8 as well for not being that sustainable on the track. This is a stupid argument comparing the efficiency numbers of this cars.
The idea of driving 250 km/h without using one litre of petrol is just entirely fascinating and futuristic. It’s a whole new world. Just don’t expect these new world to be perfect from the start.

 

[Mattias]

That means you would be averaging 130 km/h. Im not sure that is really possible to achieve (legally?). Maybe if you went through Germany, but that´s a huge detour.

 

[WarpedOne]

Let me give you an example. I would like to drive to Italy. 1300kms. I can do it in one day (10hrs total) in a ICE car. I can do it in two days (16 hrs total) in a Tesla.
That is a practical limitation. Most important one for me. Not related to this thread though.

Hmm, 10 hours against 16 hours. ..
1300 km in an ICE car doing 130 km/h average will drink well over 10l/100 km. That is 130l of petrol or 100l of diesel. At current prices that is 200 EUR for gas or 150 EUR for diesel.
If thase 6hours was that important that you are willing to spend 150 or 200 EUR, I'd say spend another 100 EUR and fly to italy and save another 5 hours.

Driving 1300 km with a car in a hurry is just plain stupid.

 

[loco]

Driving 1300 km with a car in a hurry is just plain stupid.

Yes, in a CAR it is stupid, in a Tesla it is NOT POSSIBLE.

 

[sandpiper]

Hmm, 10 hours against 16 hours. ..
1300 km in an ICE car doing 130 km/h average will drink well over 10l/100 km. That is 130l of petrol or 100l of diesel. At current prices that is 200 EUR for gas or 150 EUR for diesel.
If thase 6hours was that important that you are willing to spend 150 or 200 EUR, I'd say spend another 100 EUR and fly to italy and save another 5 hours.

Driving 1300 km with a car in a hurry is just plain stupid.

Why is it stupid? On the road by 7AM. Drive until lunch. Take nice break for lunch. Drive until dinner. If you've been slowed up a bit, do a couple of hours after dinner. I've done this a bunch of times. It's no big deal and even less of a deal if you have 2 drivers.

 

[WarpedOne]

I said in a hurry.
There are faster and safer ways to get 1300km away than driving like a madman at 130kmh (85mph) average speed for 10 hours straight.
A reasonable man does it with plenty of planning and safety margins. And stops and rest. And meals and toilets and etc.

Yes, in a CAR it is stupid, in a Tesla it is NOT POSSIBLE.

So much about being realistic. I'm done with you.

 

[supratachophobia]

This thread is great. Whoever brought up the point about researching first a 700hp auto purchase was right. But on the flip side, Tesla did nothing to tell people actively that the car would never ever see a combined motor output of 700hp. Sure it may be obscured in the fine print, but we in the corporate sense wanted to believe it and they in the corporate sense let us.

I'll repeat what I said and have heard others stating, there is no reasonable analog to daily driving, however enthusiastic, that simulates tracking the car. So why is it an issue? The focus should be on why the car is only "fast" at 50%+ charge and/or what can be done about extending performance on the road because power limiting is kicking in for daily driving (3 hard accelerations in a row).

And regarding long trips, is there an issue with driving 85mph for 650 miles? I have not seen this yet. Obviously you have to change though right?

 

[ScepticMatt]

We have nearly identical username :wink:

So we have a Matias, Mattias and Matthias (me) :smile:

 

[krisg81]

Exactly. Some people have skimmed this post and are rambling about things that aren't even related to the topic of the post I created, like WarpedOne- not sure what he's talking about in regards to it not being a track car or whatever. NO ONE expects this car to be a track car, including myself- what's so hard to understand?

let me break this down simply:

1) I did not know that the P85D performs much slower at 50% and lower battery charge than full- a HUGE difference in comparison to low SOC to my P85

2) I don't care if it goes slower on a track. I had a friend come over last night and want a test ride. My car had 31% charge. I told him to come back tomorrow when the battery is full because it won't impress you nearly as much. He laughed about it because that's pretty crappy.

I Just want the advertised power a lot more than only 100 miles of driving! The Insane button actually only works for a little bit of time as it definitely performs at Sport mode or worse under 50% battery charge.

this has NOTHING to do with repeated abuse on a track, it's simply getting the power that is advertised for a lot longer than 50% battery, period.

This thread is great. Whoever brought up the point about researching first a 700hp auto purchase was right. But on the flip side, Tesla did nothing to tell people actively that the car would never ever see a combined motor output of 700hp. Sure it may be obscured in the fine print, but we in the corporate sense wanted to believe it and they in the corporate sense let us.

I'll repeat what I said and have heard others stating, there is no reasonable analog to daily driving, however enthusiastic, that simulates tracking the car. So why is it an issue? The focus should be on why the car is only "fast" at 50%+ charge and/or what can be done about extending performance on the road because power limiting is kicking in for daily driving (3 hard accelerations in a row).

And regarding long trips, is there an issue with driving 85mph for 650 miles? I have not seen this yet. Obviously you have to change though right?

 

[loco]

I said in a hurry.
There are faster and safer ways to get 1300km away than driving like a madman at 130kmh (85mph) average speed for 10 hours straight.
A reasonable man does it with plenty of planning and safety margins. And stops and rest. And meals and toilets and etc.


So much about being realistic. I'm done with you.

Point is: long distance travel is max 70-80 km/h in a Tesla including charging. Can be 100-130 if you want it in an ICE.

I sometimes prefer the latter. Don't enjoy "zen-master" 90km/h with heater off, staring at energy graph. We all know it too well.

 

[EarlyAdopter]

Exactly. Some people have skimmed this post and are rambling about things that aren't even related to the topic of the post I created, like WarpedOne- not sure what he's talking about in regards to it not being a track car or whatever. NO ONE expects this car to be a track car, including myself- what's so hard to understand?

I had held out hopes it would be a decent track car, and after last Sunday on the track with it for the first time my expectations were far and away exceeded. The only person claiming to have had a different experience with the P85D on the track so far is loco. I'd say that at the point the jury is still out.

But yes, fair point - this thread should focus solely on how much the P85D acceleration is influenced by SOC. Range and track discussions should go elsewhere.

1) I did not know that the P85D performs much slower at 50% and lower battery charge than full- a HUGE difference in comparison to low SOC to my P85

You say "much slower" and "HUGE difference" without quantifying how much. Wouldn't it help to know exactly how much? I'm not saying it's in your head, but what if it was? Butt dynos are notoriously influenced by psychological factors.

2) I don't care if it goes slower on a track. I had a friend come over last night and want a test ride. My car had 31% charge. I told him to come back tomorrow when the battery is full because it won't impress you nearly as much. He laughed about it because that's pretty crappy.

I'm sure he would have still been very impressed, even if the low SOC P85D only accelerates like a fully charged P85, because nearly everyone was impressed with the P85.

 

[skilly]

This is getting a little too spirited for my taste. Love to see the perspectives but the rude banter just detracts from the value...

 

[doug]

A couple posts got zapped away snippiness - Page 136 .

Please be polite and stay on topic.

 

[Stoneymonster]

Honestly I don't see how we can keep discussing this without data.

It's like a pre-Internet lunchtime argument about who is the taller actor.

 

[Ldub22]

Let me give you an example. I would like to drive to Italy. 1300kms. I can do it in one day (10hrs total) in a ICE car. I can do it in two days (16 hrs total) in a Tesla.
That is a practical limitation. Most important one for me. Not related to this thread though.

I believe, sir, if this is a practical limitation most important for you, you bought the wrong car. If I wanted to haul 10 foot (3 meter) pieces of wood, the Tesla would also be the wrong choice. I think the read before you buy argument is based on the fact that people buy the wrong car for them often. They just don't often complain about it on message boards . . .

For my needs, the Tesla will hopefully be great. I get mine in a week. I have been reading this board for awhile and knew this limitation from other threads (like excellent posts from WarpedOne), so I am prepared. But who knows?

 

[Cottonwood]

Honestly I don't see how we can keep discussing this without data.

It's like a pre-Internet lunchtime argument about who is the taller actor.

This!

MotionLogger and other apps on the iPhone, and I am sure apps on an Android phone will let you log the raw, 3-axis, accelerometer data. Put the phone in a stable position for the experiment (I like flat over the cup holders), record a second or two of pre-launch data so that you have a stable gravity vector, then record the data, subtract out the gravity vector, and compare various charge levels. There are also apps that will just record 0-60 times, etc.

Have fun!


BTW, my twin-ICE, Cessna 421 has two engines rated for continuous take-off power at 375 HP each, or 750 HP total. The most that I have done is 20 minutes to climb out of weather to the flight levels. At over 60 gallons of gas per minute at those powers, it cost me over 20 gallons, but I got out of the ice (frozen water) quickly.

 

[skilly]

A couple posts got zapped away snippiness - Page 136 .

Please be polite and stay on topic.

thank you.

 

[Danal]

5-6C are actually very high C numbers for the NCA chemistry Tesla is using. The high capacity 3400mAh Panasonic NCR18650B has a 5 second burst current of 12A (3.5C). The higher power, lower capacity 2900mAh Pansonic NCR18650PF (actually a NCA, manganese spinel hybrid) 5 second bursts at 18A (6.2C). Tesla is absolutely pushing these cells to their limit at a 5-6C discharge.

I'm using third party links below since Panasonic doesn't officially rate burst current, only continuous.
http://www.orbtronic.com/batteries-chargers/panasonic-3400mah-18650-li-ion-battery-cell-ncr18650b
http://www.orbtronic.com/batteries-...i-ion-rechargeable-battery-panasonic-flat-top

You aren't talking about a high draw, low density chemistry like lithium titanate or lithium manganese (certain types) that can easily do 10-20C.

Excellent point about the chemistry. Perhaps they are drawing the line at 5.5 C. Or somewhere right around there. And the table below could easily be slightly off. Take it as "directional", not "precise or accurate".

SOC as a %:	100%	90%	80%	70%	60%	50%
Individual Cell Voltage (approx*):	4.1	4.05	4	3.9	3.8	3.75
Tesla Motors spec P85D: 671 HP/500KW:	500	500	500	500	500	500
Pack Voltage:	393.6	388.8	384	374.4	364.8	360
Amps at 500kW:	1270	1286	1302	1336	1371	1389
Parallel String Capacity, AH:	240.5	240.5	240.5	240.5	240.5	240.5
Discharge expressed as "C":	5.3	5.3	5.4	5.6	5.7	5.8
*No specs published on Tesla/Panasonic cells. These numbers are from other 'good' 18650s. They were also distorted downard to make "C" look worse, if anything. That's why 100% is not 4.2 (OK, 4.235 at 20C, don't nitpick).

 

[WarpedOne]

Motion loggers and everything, yes, off course, but modest mobile phone with a simple camera will do just fine.

Just film a 10%SOC 0-60 run and post it to YT for all to see.
It will show the power, it will show the time, it will show who is spreading FUD.

 

[sorka]

This thread pointless until we have more facts. For those claiming there isn't a huge difference in power output at various SOC levels in their P85D, lets see some videos showing KW draw on 0-60 runs. For those claiming there is a big difference, same thing.

Lots of discussion and no real data except the battery data that says there shouldn't be a big difference unless Tesla is doing something in software to limit draw at lower SOCs.