Battery degradation in cold

[Stdderm]

I have a model S 2017. I need to leave it at the airport for 3 days in Indianapolis in the cold weather. Is there a way to figure out how much battery loss will occur to make sure I can drive home when I get back?

 

[Proppilot]

For my 2021 S refresh I find about 30-35 miles/day loss if SENTRY mode is ON and only a couple miles a day if off.

 

[Stdderm]

Thanks for your reply. It’s likely to be about 15 to 20 degrees. How much you think that should change the loss of miles. I will keep sentry off.

 

[Proppilot]

Sorry not sure what degradation would be for the low temp and hopefully someone else can offer some experience.

 

[ucmndd]

Keep sentry mode off, leave the car alone and let it go to sleep, and you should lose very little energy, not substantially more than you would if it was warmer.

 

[Stdderm]

Ok. Thanks

 

[Suzach]

For my 2021 S refresh I find about 30-35 miles/day loss if SENTRY mode is ON and only a couple miles a day if off.

@Proppilot I came to the forum to ask a slightly different question but I think perhaps your comment gave me the answer. I dropped off our brand new model Y at the shop to get paint protective film put on and when I dropped it off on Friday it had 120 mi range. Now it has 60 mi and yes they have had the doors open and yes sentry mode was on but it just seems like an extreme amount of battery degradation without having the car ever moved. From what I understand from your comment though this is typical with Sentry mode on? The car eventually got down to 21% and turned sentry mode off automatically but I won't have enough change to get home now without stopping for a charge..

 

[Proppilot]

100%. Sentry takes a shocking amount of energy and if the car is awake due to work being done and doors open it is even worse ! I was shocked when I left the car at the airport for a flight to Europe and watched it drop about 20-25 miles a day. I exaggerated the situation by checking the car a few times a day as I had just taken delivery a few days prior.

This is why your car lost so much mileage. Sentry mode was on and car was awake a lot

 

[TesMY]

My Model Y has taken 7% charge in about 5 weeks now (Sentry OFF, parked in Car port, not plugged in)

 

[Proppilot]

My Model Y has taken 7% charge in about 5 weeks now (Sentry OFF, parked in Car port, not plugged in)

Exactly. With Sentry off and the car sleeping it draws very little power

 

[Suzach]

100%. Sentry takes a shocking amount of energy and if the car is awake due to work being done and doors open it is even worse ! I was shocked when I left the car at the airport for a flight to Europe and watched it drop about 20-25 miles a day. I exaggerated the situation by checking the car a few times a day as I had just taken delivery a few days prior.

This is why your car lost so much mileage. Sentry mode was on and car was awake a lot

Wow! Definitely not arguing or claiming that I don't believe you it just seems so crazy that the power it takes to drive the vehicle 25 miles is somewhat comparable to having sensors and cameras active and the car not going into deep sleep for 24hrs! Obviously if it's plugged in at your house for example it's a different story but to me this sort of makes sentry mode obsolete

 

[ucmndd]

Wow! Definitely not arguing or claiming that I don't believe you it just seems so crazy that the power it takes to drive the vehicle 25 miles is somewhat comparable to having sensors and cameras active and the car not going into deep sleep for 24hrs! Obviously if it's plugged in at your house for example it's a different story but to me this sort of makes sentry mode obsolete

Sentry draws 250-300 watts when active, so running it for an hour uses 250-300 watt hours. A Model S depending on year/trim is rated at about 250-300 watt hours per mile, so yeah. About a mile an hour.

The cameras and sensor suite were never designed to be a security system, it was an afterthought by Tesla. I suppose it's useful in rare situations, but I could never recommend using it all the time as it's a fantastic waste of energy.

 

[roblab]

@Proppilot I came to the forum to ask a slightly different question but I think perhaps your comment gave me the answer. I dropped off our brand new model Y at the shop to get paint protective film put on and when I dropped it off on Friday it had 120 mi range. Now it has 60 mi and yes they have had the doors open and yes sentry mode was on but it just seems like an extreme amount of battery degradation without having the car ever moved. From what I understand from your comment though this is typical with Sentry mode on? The car eventually got down to 21% and turned sentry mode off automatically but I won't have enough change to get home now without stopping for a charge..

My local body shop leaves all Teslas and other EVs plugged in while they have the cars. Some body shops make sure the high-end cars are brought inside, so sentry mode isn't needed, but with the car plugged in to a 220 outlet, they always are delivered with charge enough to "get home". 220-volt extensions cords are readily available, and I keep one in my frunk for just such occasions. Talk to your repair/body shop.

 

[Proppilot]

My local body shop leaves all Teslas and other EVs plugged in while they have the cars. Some body shops make sure the high-end cars are brought inside, so sentry mode isn't needed, but with the car plugged in to a 220 outlet, they always are delivered with charge enough to "get home". 220-volt extensions cords are readily available, and I keep one in my frunk for just such occasions. Talk to your repair/body shop.

Agreed. Even plugged into a 120v power outlet with the mobile adapter that came with the car will keep you net energy positive with sentry on and the vehicle awake.

 

[Rocky_H]

when I dropped it off on Friday it had 120 mi range. Now it has 60 mi and yes they have had the doors open and yes sentry mode was on but it just seems like an extreme amount of battery degradation without having the car ever moved.

And let's not confuse this with bad terminology.

"degradation" is damage that is PERMANENT lost capacity. This is just energy USAGE.

 

[Suzach]

And let's not confuse this with bad terminology.

"degradation" is damage that is PERMANENT lost capacity. This is just energy USAGE.

Fair / correct sorry for the bad choice of words!

 

[GlenF]

I had the opposite type of temperature battery drain at the airport. Summertime, and I mistakenly had left cabin overheat protection enabled (plus Sentry). I now know where this lot has the EV parking spots with 120V outlets for all my future trips.

So, my wintertime tip would be: find and use a parking lot that has outlets for EVs. And tell them how much you appreciate that they offer this, which is why you chose them over any other parking lot.

 

[Suzach]

@GlenF don't they charge fees for being connected for extended periods of time? What sort of charging bill do you rack up in this scenario?

 

[tga]

@Proppilot I came to the forum to ask a slightly different question but I think perhaps your comment gave me the answer. I dropped off our brand new model Y at the shop to get paint protective film put on and when I dropped it off on Friday it had 120 mi range. Now it has 60 mi and yes they have had the doors open and yes sentry mode was on but it just seems like an extreme amount of battery degradation without having the car ever moved. From what I understand from your comment though this is typical with Sentry mode on? The car eventually got down to 21% and turned sentry mode off automatically but I won't have enough change to get home now without stopping for a charge..

The HVAC will also run while the doors are open, further drawing down the battery.

 

[GlenF]

@GlenF don't they charge fees for being connected for extended periods of time? What sort of charging bill do you rack up in this scenario?

No, the 2 lots I've used (BWI The Parking Spot and the now-defunct Pre-Flight Parking) have 120V outlets and don't charge a fee to use them. I guess they figure the cost of keeping your battery topped up is minimal and is a good way to attract EV customers. I was surprised at how many spaces with power The Parking Spot had. Pre-Flight only had 2.