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Performance Mode Questions

Discussion in 'Roadster' started by Pantera Dude, Dec 4, 2012.

  1. Pantera Dude

    Pantera Dude Member

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    I like all the acceleration I can get. How much battery life is this going to cost me if I always drive in performance mode? I don't understand how it works. Why is there a performance charge mode? If you put the car in performance drive mode, why does it make any difference what mode you charged in? Does the charge mode somehow make the car faster. What is the difference between performance and range charge modes? I know, I ask a lot of questions. :biggrin:
     
  2. wiztecy

    wiztecy Active Member

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    #2 wiztecy, Dec 4, 2012
    Last edited: Dec 4, 2012
    I used performance mode about three times, seeing what the difference was on a straight away, another racing another Roadster in a quick sprint and pitching the back end out to do a comparison between how fast the back end will snap loose with traction control off. I'm not going to use it any more and don't see a huge difference between driving in std. mode and performance. Where you get the most performance is when you charge in performance, then switch to performance and immediately use performance mode. I believe the top 5% is its peak performance if I recall from a Telsa technician, that's where they get their 3.7 and 3.9 zero to sixty numbers. Charging in performance mode charges the pack up to its full 100% capacity so you can pull the most amps from it. Std. mode charges up to 80-87% of the pack's capacity. 100% charges stress the battery pack's cells hence why I charge in Std. Mode and use Range mode (on 220v) every now to balance the pack faster, if it needs it, and also to keep an eye on and see what my true range / health of the pack is. That's why if you let your pack sit in 100% a range mode charge it bleeds the battery down to 85% rapidly, also that top drop of the battery curve is very fast from 85-100% so you don't get that much bang for your buck there in terms of range and health.

    The downside of the performance mode is that it adds extra stress to the battery pack for that it allows the highest amperage draw from the pack. I really wouldn't use performance mode below 60-70% due to the higher stresses of the cells. Both std. mode and range mode regulate it to a conservative level/draw.

    I also would strongly keep away of driving in performance mode, you're looking at prematurely degrading your battery pack and range over time. There's a Roadster out there that does this, its always in performance mode and every stop/go the accelerator is pegged. I believe it has somewhere around 10k-20k on the odometer and is only getting around 100-110 ideal miles when charging. Unless you have tons of $$ to constantly replace the battery pack I don't recommend it.
     
  3. vfx

    vfx Well-Known Member

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    What he said^^^^

    and it allows the battery to overheat. That is, it will not give you an "overheating" message and then reduce the cars speed till it cools off. So it is hard to say how much damage you are doing because you don't know when it would have slowed you down (The car does not tell you that you would have been slowed down)
    I think you can look at your temp gauges but not sure if they are recalibrated when in Performance mode. Prob not.

    I never use it unless it's an official engine-rev drag race. Not only is it an infantesimal gain as Wiztecy says, you always have to put it in that mode manually.
     
  4. Pantera Dude

    Pantera Dude Member

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    I can see how there is extra energy available to make the car go faster on a performance charge. But what if you do a standard charge, is there any difference in performance between standard and performance driving mode? Is it just that the car is allowed to do more acceleration runs or is the car actually any quicker?
     
  5. djp

    djp Roadster 2.0 VIN939

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    Charging in Performance Mode and charging in Range Mode will both reach the same State Of Charge, but the Performance charge gets there faster. The Performance Mode charge also allows the battery to get hotter while charging to more efficiently deliver power if it's immediately driven.

    The faster charge and higher temperature both stress the battery and reduce it's life, so Performance Mode charging should be used sparingly, but you'll get the best acceleration if you drive in Performance Mode directly after a full Performance charge.

    You can drive in Performance Mode after a Standard charge, but won't get the same amount of juice out of the battery.

    I notice Performance Mode driving makes the biggest difference in the 60km/h to 90km/h range. Of course now that I have snow tires on it's pointless. :(
     
  6. wiztecy

    wiztecy Active Member

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    #6 wiztecy, Dec 4, 2012
    Last edited: Dec 4, 2012
    "Charging in Performance Mode and charging in Range Mode will both reach the same State Of Charge, but the Performance charge gets there faster."

    I don't think that's true, that would mean performance mode is pulling more Amps out of your charger/and from the source from your house. When I charge in std mode, range mode I don't see any difference in the Amps the car's taking in, it's taking as much as you supply it (up to 70 Amps from the source (minus the overhead). If your heating the pack up more while charging, you're not efficiently charging since the energy going in is going out in heat. The only time I see my amps start to drop while charging the Roadster is at the top 97% of the charge, and that's to top it off without overflowing the battery like a garden hose turned wide open. You can monitor this though OVMS easily to see it.

    djp, did you time the two charges starting from the same ideal miles? If so I'm curious what your times were. I could be wrong but I just don't see this happening, the only thing I could see is ignoring the fans and condenser to cool the pack down while charging but that doesn't buy you much and personally I wouldn't like that implemented on my car unless I had a sponsor paying for all my battery packs.
     
  7. Doug_G

    Doug_G Lead Moderator

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    It probably is somewhat true, in that Performance mode minimizes HVAC usage and lets the battery go up towards its max limits (40C), whereas Range mode tries to chill out the battery as much as possible. Therefore in Performance mode there's less energy spent on HVAC and more on charging.
     
  8. strider

    strider Active Member

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    Perf driving mode also seems to make the accelerator "snappier" - ie less travel is required to accelerate quickly. It will allow the batteries to heat up more than standard mode but Scott has said that he's planning on driving his 2.5 in Performance mode all the time. I asked him about battery health and he wasn't concerned so YMMV. If I ever go to the track I'll charge in Perf (as others said it diverts less power to cooling so it can charge faster) but otherwise I charge in range and then sometimes drive in Perf if I'm expecting a highway merge, motorcycle pulls up next to me at a stoplight, etc. No harm in switching between standard and perf while driving.

    I'm glad they got rid of Perf in the Model S - my wife would never have put up w/ all the extra fiddling.

    - - - Updated - - -

    I agree.
     
  9. Pantera Dude

    Pantera Dude Member

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    Ok, I think I'm starting to get some of this. :tongue: It seems that performance "drive" mode will allow the battery to release more energy than standard drive mode. It makes sense to me that the motor would have more energy available with the A/C off, just like in an ICE car. There have been some ICE cars that would shut of the A/C pump during hard acceleration, I assume our cars don't do that? I can also understand how the battery could charge more quickly if the energy that normally goes to cooling is diverted to charging.
    Have I got all of this right?
     
  10. vfx

    vfx Well-Known Member

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    My most favorite part of driving ownership. Bar none.
     
  11. hcsharp

    hcsharp Active Member

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    It's not just the HVAC. A warmer battery has less internal resistance so it can let more amps pass through it. That's part of the reason it charges faster than range or std mode. Also while driving, I believe in Perf mode the PEM puts a few more amps to the motor regardless of temperature.
     
  12. djp

    djp Roadster 2.0 VIN939

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    I haven't actually timed it myself, but a Ranger told me the Performance charge is faster than a Range charge. Less energy is diverted to HVAC and the charging efficiency is better at a higher temperature with lower internal resistance.

    Pantera Dude, I think you've got it now. The most confusing part is that charging in Storage / Standard / Range / Performance mode has nothing to do with driving in Storage / Standard / Range / Performance mode.
     
  13. Doug_G

    Doug_G Lead Moderator

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    Yeah, but the A/C takes at most 3 kW as I recall. Compared with > 200 kW full throttle. It's pretty small.
     
  14. Pantera Dude

    Pantera Dude Member

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    Thank you all for your help!
     

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