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Regen braking reduced to only -30 kWh. Why? Is there a way to "pre-heat" the battery while still plu

browng1_93439869browng1_93439869
edited November -1 in Model S
Hi there,
So I'm up in the midwest and it was about 50 degrees F when I got into my Model S 70D this morning. It really wasn't that cold. When I got in the car I got a warning symbol near the - 30 Kwh mark. It was a yellow "exclamation symbol" and then from -30 to -60 Kwh it was a dashed yellow line. The car basically said to me "You can only regen up to -30 Kwh, not the full -50 like normal"

Why do I get this warning? Was it too cold? 50 degrees F doesn't seem very cold to me. It finally went away, but it took 30 minutes of driving to go away.

I have another related question. Is there a way to "pre-heat" the battery before driving, while it's still plugged in? I would rather the car pull the electricity from my house to pre-heat the battery, instead of my pulling out of my driveway and the car using the battery to pre-heat itself. This isn't a big deal for around town driving, but pre-heating the battery before a road trip just before we leave (while still plugged in) would be REALLY helpful.

thanks!

Comments

  • BighornBighorn
    edited November -1
    I saw some limited regen at 58F the other day--didn't last long. In colder temps, we use the climate app to prewarm the car and precondition the battery.
  • alex_93452336alex_93452336
    edited November -1
    @browng1

    Your car was probably much colder over night, and since it does not use much energy when turned off, the battery was colder than 50 degrees even while the air temperature was 50.
  • WØQRWØQR
    edited November -1
    Absolutely normal. And you'll get that limitation too if you do a range charge. The battery has eaten all it can and can't take no more.
  • stevenmaifert_12203stevenmaifert_12203
    edited November -1
    The battery software will limit the rate of charge until it is heated or cooled to a preset temperature range. Using the Smart Pre-conditioning feature will heat or cool the cabin but I didn't see in the owner's manual where it does the same for the battery. If you depart daily at about the same time, you could set the charge timer to charge the car for a while prior to your departure. If the battery temp is outside the range on the cold side, the battery will be heated prior to charging. I don't know if this would entirely eliminate the limited regen when you depart, but it would stay on for a shorter period.
  • BighornBighorn
    edited November -1
    @steven
    One of the firmware updates stated that battery preconditioning happened along with climate preconditioning. I agree that charging the battery before departure is another strategy that can help.

    I'm rather surprised that it took 30 minutes for the regen limit to abate with a temp near 50F. That's how long it would take for sub zero temperatures. Older firmware didn't always continue to show the dotted yellow line even when regen was still clearly not able to max out. Maybe the yellow line is more accurate now?
  • TabarnoucheTabarnouche
    edited November -1
    Page 44 of the manual: "If Model S is plugged in, you can heat your Battery using wall power by turning on climate control using the mobile
    app."
  • jordanrichard_629778jordanrichard_629778
    edited November -1
    I got the regen limitation at just about 30 kwh. This was after the car had been sitting outside all day today, while I was at work. The ambient temperature was 53 degs F. The lines stayed there for the 4.5 mile drive home. Now, I am not a newbie as I have owned my car for just about 19 months. So I am familiar with the car's reactions to cold conditions, but I did find it odd to see these lines, when it was 53 degs out.
  • BighornBighorn
    edited November -1
    @jordan
    Last year my threshold was 50F. So far I've seen it as high as 58F since v7.
  • David TrushinDavid Trushin
    edited November -1
    @bighorn, sounds like you have range mode on. Battery conditioning is turned of when range mode is on and it will take 30 minutes for the battery to heat up on its own.
  • BighornBighorn
    edited November -1
    @David
    I don't have range mode off, but the OP may. Good point.
  • Dwdnjck_137170Dwdnjck_137170
    edited November -1
    So? Does this make any difference. Limited regen for a few minutes? How much range does one lose? Surely measured in feet rather than miles.
  • David TrushinDavid Trushin
    edited November -1
    For a few minutes, no. But when it gets really cold, or if you are using range mode it could make a big difference. Smart preconditioning is often a good alternative. I just use the phone app to preheat the car and that warms the battery.
  • browng1_93439869browng1_93439869
    edited November -1
    Thanks everyone for the helpful comments.

    Regarding pre-heating the battery: It sounds like this can only be done via the mobile app. So, if the car has stopped charging 8 hours ago, and I know I'm going to leave for a road trip in 30 minutes, I can simply turn on the climate control via the mobile app and that pre-warms the battery?

    I don't have Range Extended mode on (it's Off). I don't use "Smart Preconditioning."

    Anyway, it sounds like the best way to pre-heat the battery is to use the mobile app and turn on the climate control (while it's still plugged in).
  • jordanrichard_629778jordanrichard_629778
    edited November -1
    browng1, yes. You could also just schedule your car to start charging in time for it to be complete just before you are due to leave.
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