Pack Performance and Launch Mode Limits

[stopcrazypp]

Just to clarify my friend I referred to previously is Tech_Guy and since he is now posting I can reveal his identity.
@Tech_Guy
Were your launches for demonstrating go pedal or Launch Mode?

Just took a look at this thread. The way the response was worded is that this applies only to Launch Mode. So wouldn't the "solution" be just to not use launch mode after you hit the limit? If I recall correctly, launch mode only resulted in a 0.1 second difference in 0-60, if that.

That's much better than taking a uniform hit in power beyond just launching. But I get the outrage over this, given this is a lifetime limit and not just temporary.

 

[stopcrazypp]

Did they offer to give any examples of this "common" strategy?

If I have to take a guess, they are referring to the GTR's update on launch control:
Nissan instructs dealers to reprogram GT-R launch control

They settled a class action lawsuit with the given update and a $75 service coupon.
http://jalopnik.com/5565919/this-is-nissans-gt-r-launch-control-warranty-settlement/

 

[MP3Mike]

Just took a look at this thread. The way the response was worded is that this applies only to Launch Mode. So wouldn't the "solution" be just to not use launch mode after you hit the limit? If I recall correctly, launch mode only resulted in a 0.1 second difference in 0-60, if that.

That's much better than taking a uniform hit in power beyond just launching. But I get the outrage over this, given this is a lifetime limit and not just temporary.

The way I read it is 25 "good" launch mode uses permanently reduces your available power for everything, even non-launch mode uses.

If the information is accurate the solution is to not ever use launch mode.

 

[apacheguy]

The data I've seen shows the advertised pack current dropping, not the max DI current.

Thanks. Do you have the message decode for max amps from the BMS?

 

[stopcrazypp]

The way I read it is 25 "good" launch mode uses permanently reduces your available power for everything, even non-launch mode uses.

If the information is accurate the solution is to not ever use launch mode.

I'm referring to the statement by the Tesla rep, which only ever talks about launch mode, and not just launches in general:
"Depending on how launch mode is used, the computer may eventually limit the available power during launch mode to protect the powertrain."

If it only applies when launch mode is active then the impact is far less. I get that it may still limit power throughout if launch mode was active, but I'm saying, say for example you launch without launch mode, then presumably you should be able to get full power (although I'm not sure how this gets reset if you used launch control in a previous run, perhaps you have to restart the car).

 

[apacheguy]

Thanks Ingineer, great informative posts.
Since we're talking about battery capacities and launch limitations, could you also comment about launch limitation in 60/70/75 cars?
I drove a S75 and noticed that how slow was 0-60. Especially 0-30. 0-30 felt much slower than my old Bmw 630. It was like the car didn't want to move first 1-2 seconds.
Then I've tried 10-60, which really felt fast, even comparing to my P90DL, it was good. It is obvious that Tesla is limiting the power of S75 if you are doing "launch" from 0. Rolling start from 10mph is definitely much faster.

Have you got any data on that? Since lots of people have 60/75s, that maybe more interesting than P90D limitation for some people.

(Btw, in my opinion one reason that P90D is much more expensive than 90D is to cover the extra risk of drive train failure. If they are limiting launches, this is bad.)

One reason that 0-30 feels slower is because of torque. The beefier drive units deliver much more torque. Even though the maximum power is similar (my S85 can produce 326 kW while a P85 does about 360 kW) the difference in performance at the low end is very obvious because of the greater torque.

 

[rowdy]

Pretty sure that's just the pre-programmed torque curve though. I'm certain that a base Tesla could perform better if Tesla wanted to (afterall it's just 350V vs 400V), but then it would make it hard to differentiate between the product levels. Would you pay extra for the P if the base wasn't that much slower.

Interesting that 10-60 is much more spirited. Will make for some interesting vbox comparisons

 

[AnxietyRanger]

I'm referring to the statement by the Tesla rep, which only ever talks about launch mode, and not just launches in general:
"Depending on how launch mode is used, the computer may eventually limit the available power during launch mode to protect the powertrain."

If it only applies when launch mode is active then the impact is far less. I get that it may still limit power throughout if launch mode was active, but I'm saying, say for example you launch without launch mode, then presumably you should be able to get full power (although I'm not sure how this gets reset if you used launch control in a previous run, perhaps you have to restart the car).

Earlier in this thread claim was made this happens without launch mode, so any full launch would - if accurate - cause the counter to rise.

 

[Old Man Mike]

Any thoughts on the launch reduction algorithm being based on all standstill launches or only those at Max battery and high battery SOC?

Also, what is the easiest method for individual owners to test for pertinent performance metrics and help shed some light on this issue?

The easiest and most consistently accurate way is to use the Tesla Power Tools app available for iPhones. Lots of data from that app was posted in this thread: Max Power vs State of Charge and Temp

 

[rowdy]

If I have to take a guess, they are referring to the GTR's update on launch control:

For background with the GT-R it's true that the transmissions were a weak point at launch. In 2008/2009 failures started to show up. The cars do log everything though which allowed for analysis back in Japan.

In 2010 nissan pulled launch control completely (it's not in that years model).

In 2011 they brought it back, faster but now with restrictions. Ensure the car is up to operating temperature then you can do launches. If you need to do more than 4 in a row you need to drive it 2 miles to let the drivetrain cool down.

Since it's outlined in the manual there is no confusion. "If the R mode start function is used 4 times continuously, the function may be disabled and cannot be turned on for protection. While the function is disabled, the warning light illuminates. When the warning light goes off, the function can be used again."

It's a very different situation to have a temporary lockout versus a lifetime counter.

I should also mention that last year I had a friend with a 2009 GT-R suffer a transmission failure. Despite being 3 years out of warranty Nissan decided to provide him with a replacement transmission for free (they are worth $20,000). The early transmissions simply weren't up to the task and it was great to see Nissan make it right even after all this time.

 

[scaesare]

Pretty sure that's just the pre-programmed torque curve though. I'm certain that a base Tesla could perform better if Tesla wanted to (afterall it's just 350V vs 400V), but then it would make it hard to differentiate between the product levels. Would you pay extra for the P if the base wasn't that much slower.

Interesting that 10-60 is much more spirited. Will make for some interesting vbox comparisons

If you are responding to @apacheguy, I don't believe this is accurate.

The pack voltages for "Base" and P series cars are the same (~400V peak). The difference is the amount of current the P cars can pull from the pack.

The 60kWh packs are indeed lower voltage, but there is no P version available for them.

 

[Andyw2100]

Here is the deal..

This only impacts P90Ds. There is a lifetime counter on launches. However, to count as a launch a bunch of crieteria must be met:

1. Launch mode must be on
2. SOC must be >90%
3. Perfect traction must be maintained. Any amount of slip will cause power to be reduced and it won't count.

The limit is 25 for the rear drive unit. If this limit is hit, power is reduced slightly resulting is a difference of 0.05s 0-60.

Basically, unless you regularly take your car to the drag strip and can manage to maintain perfect traction while meeting all or the other conditions above, this is a non-issue.

I encourage everyone not to blow this out of proportion.

For me the issue is not the number of cars affected, but rather what this says, yet again, about Tesla's corporate attitude.

It appears to me that once again, Tesla is taking the stance that since not that many cars will be affected, and since not very many of those owners are likely to even notice, they'll try something that is somewhat shady, and would never fly if it affected many owners and was brought to light.

"Let's just limit the power, to save ourselves warranty replacement costs. Very few people will even know. It'll be fine."

"Let's call it 691 Motor Horsepower. No one is likely to realize it isn't 691 HP. At least not for a while. It'll be fine."

"Let's understate the power available in almost all our packs. Most people won't notice. It'll be fine."

"Let's suddenly start using 1 foot roll out in our 0-60 times, without telling anyone. They'll never know. It'll be fine."

I had hoped Tesla had learned from some of their past mistakes. This issue, no matter how few people it affects, shows me that they have not. This is where my concern lies.

 

[yak-55]

For me the issue is not the number of cars affected, but rather what this says, yet again, about Tesla's corporate attitude.

It appears to me that once again, Tesla is taking the stance that since not that many cars will be affected, and since not very many of those owners are likely to even notice, they'll try something that is somewhat shady, and would never fly if it affected many owners and was brought to light.

"Let's just limit the power, to save ourselves warranty replacement costs. Very few people will even know. It'll be fine."

"Let's call it 691 Motor Horsepower. No one is likely to realize it isn't 691 HP. At least not for a while. It'll be fine."

"Let's understate the power available in almost all our packs. Most people won't notice. It'll be fine."

"Let's suddenly start using 1 foot roll out in our 0-60 times, without telling anyone. They'll never know. It'll be fine."

I had hoped Tesla had learned from some of their past mistakes. This issue, no matter how few people it affects, shows me that they have not. This is where my concern lies.

Andy, the problem is much worse than this. The problem is not that they haven't learned, that is the symptom. The problem is that Tesla doesn't recognize these as mistakes. This harsh reality will come to them later (maybe much later) when competitors arrive with a better understanding that customer loyalty is hard won, and easily lost. Success breeds hubris, even in innovative companies.

 

[xborg]

For me the issue is not the number of cars affected, but rather what this says, yet again, about Tesla's corporate attitude.

It appears to me that once again, Tesla is taking the stance that since not that many cars will be affected, and since not very many of those owners are likely to even notice, they'll try something that is somewhat shady, and would never fly if it affected many owners and was brought to light.

"Let's just limit the power, to save ourselves warranty replacement costs. Very few people will even know. It'll be fine."

"Let's call it 691 Motor Horsepower. No one is likely to realize it isn't 691 HP. At least not for a while. It'll be fine."

"Let's understate the power available in almost all our packs. Most people won't notice. It'll be fine."

"Let's suddenly start using 1 foot roll out in our 0-60 times, without telling anyone. They'll never know. It'll be fine."

I had hoped Tesla had learned from some of their past mistakes. This issue, no matter how few people it affects, shows me that they have not. This is where my concern lies.

Andy, the problem is much worse than this. The problem is not that they haven't learned, that is the symptom. The problem is that Tesla doesn't recognize these as mistakes. This harsh reality will come to them later (maybe much later) when competitors arrive with a better understanding that customer loyalty is hard won, and easily lost. Success breeds hubris, even in innovative companies.

Well, they've lost me. I'll never get a P car again until they fix these things. (with a good trade in offer or whatever etc.).
I'm writing here, If I upgrade to AP2, it will be a 60.

 

[SDRick]

The easiest and most consistently accurate way is to use the Tesla Power Tools app available for iPhones. Lots of data from that app was posted in this thread: Max Power vs State of Charge and Temp

Now that's the answer I was looking for. Just downloaded the Tesla Power Tools app, wish I would've done it when my car was new.

Also, an interesting thread pointed out by old Man Mike. Certainly some germane information in that thread. One would think that with all the enthusiasts and lead foots, it should not take too long to shed more light on these concerns.

 

[sorka]

He was concerned that Tesla would take further action if he complained too much or make it public. I found out about this when I encouraged him to take the car to the drags and get the magic 10.9 since he had the version2 90 battery. It took him one month before Tesla finally admitted they cut the power down to a version 1 (450 to 400). Since Tesla never admitted that there was a version 2 and 3 90KW battery he could not prove that Tesla had misled him as the increased power was never stated.

400? My 85 Ludicrous upgraded pack hit 455 the other day starting max acceleration from about 40 MPH. I haven't logged from 0 mph in ages. 400 is even less than the old 85 insane mode (415 kw max).

 

[sorka]

This is basically the same behavior that has manifested in other changes/downgrades.

The 691 hp * issue was never a downgrade. It was missing 228 hp from the very beginning

 

[sorka]

UBefore this limitation my car would pull around 1600 amps from the battery and 512 KW of power when fully charged, now the car will only pull around 1500 amps and and 480KW of power, a loss of about 40 HP on a 4 month old car. I was giving lots of test rides to strangers showing off the car etc as I attend a few car shows a week and I'm was quite upset to have discovered this limitation the hard way rather then Tesla letting us know at purchase about these limitations. After a month of back and forth with Tesla on this I received this reply.

The P85DL is already limited to 1500 amps so I guess that explains why the P85DL isn't effected.

 

[MikeMayhem]

"They are also taking away output current after too many launches on some packs"

It is not an X in Y time, it is different in my car every time. It's more a temperature trigger that reduces power coming from the pack, it you find your self in a power reduced start, turn off max battery power and let the car cool down... 30 - 45 min seems to do the trick.

As I understand this, Launch mode is stressful on the pack and heats it up...
IE: select max battery power, do 3 launches and the time to heat up the battery is far reduced in my car. So if when you first turn it on, lets say its claiming 45 min to heat the pack, after 3 launches in my car in a matter of say 5 min, that initial 45 min decreases to about 15 min.

That is in my P85D. I can speak to that based on my experience with the car

So I believe it is Thermal protection as someone previously pointed out.

I agree that Tesla should be more open about some aspects of the car but at the same time, they can't be expected to release absolutely every detail. If they did, they could easily lose their competitive edge.

Also, on the track I have run a 0 - 60 time of 3.195 sec my average is 3.3. This is the thing I wish could be more consistent but at the end of the day, the glue you to the seat difference between 3.2 and 3.5 is really not all that much.

 

[Andyw2100]

So I believe it is Thermal protection as someone previously pointed out.

Have you read the whole thread? Thermal protection is a known issue, and not at all what it being discussed in this thread as a problem.

Several posters have confirmed that Tesla is limiting power based on a lifetime counter. You could do one launch a day, and eventually wind up limited if you are driving a P90DL, which for now appears to possibly be the only model being limited.