Warming up Car Battery?

[cirrussk]

I have a 2016 S75

My car parks outside and I live in Phoenix AZ. It’s plugged in at night to a Tesla home wall charger.

Past week or so it’s been winter weather here, with the lows around 45 degrees. I’ve been waking up and trying to pre-heat my car, so I can drive without the regen limit.

I thought to preheat the car, that meant turning on the climate control. So I’ve been doing that for 5-15 min prior to departing, though that hasn’t preheated the car to around the regen limit

In addition, I’ve tried charging the car a little bit more in the morning, again 5-15 min, that too hasn’t preheated enough to remove the limitation.

What’s the most effective way to preheat the car battery to avoid this? I live by the Scottadale supercharger, so yesterday the charging took forever because the battery was still cold when I got there.

Thanks

Sam

 

[NickFie]

Still working it out in Philadelphia.

1. Try starting your home charging later so your battery is still charging when you're ready to leave. You can also tell the car to limit home charging to 30 or 40 Amps so it takes longer.

2. Try turning on the heat at least 30 minutes before you want to leave. This activates battery heating, warms your interior without tapping the battery.

3. Disable Range mode. Apparently Range mode limits the amount of battery heating.

4. Recently saw a video of Yo-Yo driving to heat the battery. Do this on lightly traveled road. Accelerate hard, then regenerate hard. Repeat the cycle until battery is warm enough. This leverages the battery's energy to heat it. Your car should be able to ramp up charging more quickly. It will need a bit more time at the SuperCharger to replace the energy used.

 

[DJP31]

I’m confused by why you need to go to the Supercharger that you live close to when you have a home wall charger?

 

[nwdiver]

1. Try starting your home charging later so your battery is still charging when you're ready to leave. You can also tell the car to limit home charging to 30 or 40 Amps so it takes longer.

That's what I do. Don't get FULL regen on really cold mornings but at least I have some...

 

[OlderThanDirt]

Because we can charge at high rates we somehow think we have to...... Thats just not true especially in winter. Its easier to let the car do the work and start charging later rather than manually increasing the charge level before you leave. I charge off peak anyway so the only change was reducing the charge rate.

In reality I really don't concern myself with the reduced regen phenomenon other than being aware of it. It is what is.... This is our sixth winter driving electric, we just charge it and drive it.

 

[jlund]

Turns out the most effective way to pre heat the battery is to get the latest firmware update and somehow get access to upcoming mobile app update

This just in: Tesla is working on a battery pre-heating feature to maximize efficiency in cold climates

 

[OlderThanDirt]

It would be sweet if Tesla would add control of the heated wipers and full defrost control to the mobile app!!

 

[Darmie]

Oh WoW. Something to look forward to with the .50 firmware update. Not that there's much of a problem here in the South. We are doing a trip up to Rhode Island this coming weekend and it would be nice to have this option on those cool mornings.

 

[DriveMe]

I am on 2017.50, but the new App is not out yet. Currently my app is 3.2.2 (iOS).

I wold love to have the battery preheat feature! My daily commute is relatively short, so I almost never get the full regen unless I go out of town.

 

[BerTX]

Oh WoW. Something to look forward to with the .50 firmware update. Not that there's much of a problem here in the South. We are doing a trip up to Rhode Island this coming weekend and it would be nice to have this option on those cool mornings.

Note that the car must be plugged in for the battery heating to work.

 

[Krazaak]

Something I've been fiddling around with lately is using the max battery performance option to heat the battery while it's still plugged into the HWPC in the garage. I leave one of the doors cracked slightly so the car doesn't shut back down when I close the door. It definitely seems to improve efficiency, but I've been concerned about possible negative effects so I've only done it when preparing for a longer trip where I might need the extra range. I'm assuming that max battery power option is only available on the performance model cars?

It sounds like this pre-heat from the app will just be doing the same thing I've been doing, but without the need to trick the car into staying on.

 

[mspohr]

Tesla is working on a battery pre-heating feature to maximize efficiency in cold climates

 

[Darmie]

Note that the car must be plugged in for the battery heating to work.

Yes, good point, thanks.

What I'm always amazed at is even when charging on 110v, how warm it gets in the cabin compared to the outside of the car. I see this often.

 

[BerTX]

Yes, good point, thanks.

What I'm always amazed at is even when charging on 110v, how warm it gets in the cabin compared to the outside of the car. I see this often. View attachment 267623

I never realized that. Heat rises, I guess. Thanks.

 

[animorph]

Yes, good point, thanks.

What I'm always amazed at is even when charging on 110v, how warm it gets in the cabin compared to the outside of the car. I see this often. View attachment 267623

I don't see my cabin temperature changing more than a degree on TeslaFi during 2 hours of 68A 250V charging. Outside temperature also constant, though cabin is 6-7 degrees F hotter before, during, and after.

 

[Krazaak]

Yes, good point, thanks.

What I'm always amazed at is even when charging on 110v, how warm it gets in the cabin compared to the outside of the car. I see this often. View attachment 267623

Inside a garage or outside?

 

[Darmie]

Inside a garage or outside?

We're staying at an apartment and these are short rows of buildings, not attached to any home. It could be just the location of the temp sensors. Even when it's down in the 50 to 60's the car when charging is always much warmer inside.

 

[Krazaak]

We're staying at an apartment and these are short rows of buildings, not attached to any home. It could be just the location of the temp sensors. Even when it's down in the 50 to 60's the car when charging is always much warmer inside.
View attachment 267726

Just took a look at some of my longer charges on cold nights and I'm seeing a similar difference. 34 exterior and 67-65 interior over a 4 hour charge. So it cooled down by a couple degrees during the charge, but not a ton. Interestingly enough, 9 hours after charging completed, the car woke up for a morning drive with 75 interior temp, so it must be pre-conditioning.

 

[phaduman]

If you charge your battery to 90% for the overnight charges, I think the battery gets warm enough on its own to give you what you want. Don't have the stats to prove it, but in our milder California weather (low 40s outside in the morning, low 50s in the garage), if I charge to 70 or 80% overnight, I do get the reduced regen notice, but if I charge to 90%, I haven't got a single such warning (this is over 1 winter only though)...

 

[Krazaak]

If you charge your battery to 90% for the overnight charges, I think the battery gets warm enough on its own to give you what you want. Don't have the stats to prove it, but in our milder California weather (low 40s outside in the morning, low 50s in the garage), if I charge to 70 or 80% overnight, I do get the reduced regen notice, but if I charge to 90%, I haven't got a single such warning (this is over 1 winter only though)...

I charge to 90% nightly on a 48A 240V circuit, so my charge is usually complete by 9-10pm. I see reduced regen every morning, but it's a little colder here in NC.

Even if I pre-heat the cabin, I'm still experiencing reduced range and regen from a battery with 10-12 hours of moderate cold soaking. Nothing as bad as sub freezing temps, but low 30s and 40s.

Definitely looking forward to being able to pre-heat the battery on wall power. I won't use it every day, but I will definitely use it for trips where I can skip a supercharger stop that might be 15-20 minutes off my travel route.