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Winter preconditioning and max regenerative braking

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I live in Boston and lately I've been using Preconditioning and Scheduled Departure. However, I've noticed that my regen braking is still not 100% ready once I get in the car. I mean, I believe preconditioning helps a little bit--so instead of 8 dots, I will see 5 dots or something.

Is this normal? My max charge is set to 85%, so I know it is possible to achieve full regen braking. I just want to be able to wake up in the morning and have everything ready to go, without seeing the regen dots.

Do I need to manually precondition multiple times? Or maybe something's wrong with my system and I need to have it serviced?
 
I believe it is normal. cabin conditioning also does some battery conditioning but it stops at a colder temperature than say 2 years ago. I believe target heating is around 7C, and the battery will continue to warm up with remaining heat from the stators, maybe up to 10-11C. You might not have full (85kW max) regen at that point but you have good (50-60kW max) regen. It is much less wasteful in energy than before. Drive just a little bit and the rest will come. You can also use the option to apply friction brakes automatically so it always feels like full regen if you prefer.
 
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I am similar issue as well. Where the car is plugged in and set departure time is set and still seeing partial regen.

The other issue I have seen is where the car is ready with pre-condition and full regen and while driving 10-15 minutes into the morning commute the regen partially available will show up even after the car was pre-conditioned.
 
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Just in the last couple of weeks I've been driving mostly our model 3 and sometimes our model Y with Scan My Tesla running. Of the well over a hundred parameters available, I've found the Max Regen value (kW) to be the most surprisingly informative.

I'm bringing it into this discussion because it has highlighted my understanding of the importance of hills and of recent propulsive vs. regen power in the question of how much regen is available at any given moment.

Here in Albuquerque I live at 6220 feet, and any trip is certain to have me going downhill a bit in the first few miles. Up to 1000 feet downhill, and at a quite moderate slope which is nevertheless enough to put my trip net power consumption at near zero after the first few elapsed minutes.

This matters to available max regen, which turns out to be highly sensitive to recent power flow. Just going down the four mile hill from here to church lowers the max regen on my model 3 RWD from 28 to 38 at departure down to 12 to 15 at the bottom of the hill. For the model Y LR it drops from about 48 to 15 to 20.

On the other hand, a single acceleration from stop to 55 mph can raise max regen immediately by over double.

This "recent history" effect seems to me quite important, but I have not seen it discussed here as much as the better-known state of charge and battery temperature effects.

Oh, and, by the way, the battery median cell temperature at the start of my trip this morning was about 53F, and had not changed by even 1F by the bottom of the descent (and it had not dropped) so battery cooling seems not to be the mechanism for the recent history effect.
 
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I have observed these variations in max regen based on recent driving as well, and commented them on a couple of posts. I've noticed this only when the battery is still cold-ish and I have not reached max regen. I don't live in a very hilly area so cannot comment whether regen would eventually drop after a very long descent.
 
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Tesla changed the regen profile this summer, more often limited regen.

My own guess/conclusion is that thay did find the degradation coupled to high power regen with a cold battery did too much harm so they inreased the limitation for regen power at low cell temp.

I use a lower SOC profile then most people do, I charge to 55% as the normal SOC target and I often charge shortly before the drive = warm battery and do not se any regen limit.

Regen is more limited at high SOC than it is at low SOC, for the same cell temp.
 
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Tesla changed the regen profile this summer, more often limited regen.

My own guess/conclusion is that thay did find the degradation coupled to high power regen with a cold battery did too much harm so they inreased the limitation for regen power at low cell temp.

I use a lower SOC profile then most people do, I charge to 55% as the normal SOC target and I often charge shortly before the drive = warm battery and do not se any regen limit.

Regen is more limited at high SOC than it is at low SOC, for the same cell temp.
That makes sense for everyday driving. But what do you recommend for a long trip where SOC has to be closer to 100% at departure?
 
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That makes sense for everyday driving. But what do you recommend for a long trip where SOC has to be closer to 100% at departure?
Charge to high SOC whenever you need to. Don’t worry about preconditioning unless you need the extra range/efficiency to complete your trip. Schedule charging to complete shortly before your departure.
 
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That makes sense for everyday driving. But what do you recommend for a long trip where SOC has to be closer to 100% at departure?
I need full charge frome time to time.

A full charge at max 11kW AC set my battery temp at about 28C when parked in my 10C garage which is much warmer than preconditioning get the battery.

So charge shortly before the drive is good in cold weather as the consumption is lower when there is heat in the battery to use by the heatpump.

If it is not cold ouside there is no need for the battery heat, but charging just before the drive still is a good idea as it reduces the calendar aging.
 
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I need full charge frome time to time.

A full charge at max 11kW AC set my battery temp at about 28C when parked in my 10C garage which is much warmer than preconditioning get the battery.

So charge shortly before the drive is good in cold weather as the consumption is lower when there is heat in the battery to use by the heatpump.

If it is not cold ouside there is no need for the battery heat, but charging just before the drive still is a good idea as it reduces the calendar aging.
Is there a reason you charge at 11KW? My wall connector goes to 48KW, which is overkill for nightly charging. Should I maybe turn that down.
 
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Is there a reason you charge at 11KW? My wall connector goes to 48KW, which is overkill for nightly charging. Should I maybe turn that down.
Misunderstanding. You are probably misreading kW as Amperes. There is no Wall connector which can get up to anywhere near 48 kW. But 48 Amperes at whatever voltage your 240 connection delivers is probably your maximum power.
 
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Is there a reason you charge at 11KW? My wall connector goes to 48KW, which is overkill for nightly charging. Should I maybe turn that down.
11kW is the max charging power model 3 and Y can take on AC charging.
Thats the reason.

I do not need to use lower power to reduce the load for the house incomling power and I like to charge as late as possible to reduce the calendar aging.

In wintertime, in my very cold climate, I like it hot. (The battery ;) ).
So charging late with maximum power heats the battery most before the drive.

Also, but not any reason that I do it:
11 kW will give you the lowest charging losses. The car is awake at charging, drawing some 200W only to be awake.
The fastercthe charge, the shorter time the car is awake.
Also, the slower the charge the more losses in the on board charger.
 
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