Battery drain while parked or car in storage

[geometro]

If you've used Stats in the past, and your password you used has not changed, you don't have to be logged into the app, or even have the app installed, for it to ping the car. Another possibility is something like ABRP from a prior trip.

If you're still confused, or you don't believe Tesla, as I said earlier, get a 12V battery monitor, which relatively easily allows you to see whether your car is sleeping properly. It's super easy to set up.

I believe you, but I’ve never used stats or teslafi (or any 3rd party app, ever).

 

[AlanSubie4Life]

I believe you, but I’ve never used stats or teslafi (or any 3rd party app, ever).

Yes, I believe you, too! Hence, my comment about dumping $30 or whatever on a 12V monitor so that you can easily double check Tesla's claims about the frequent wake ups, if changing your password did not work. Definitely the password change is a nice easy way to cut off everything except the Tesla app - it's a good recommendation from Tesla if that's what they are seeing.

If you don't have frequent wake ups (you should hear frequent clunking (meaning once every hour or two) from the car if this is happening), then not sure how to explain the behavior.

Generally I see about 1-2 rated miles of loss per day (about 240-480Wh), with one or two wake ups per day - the car is idle for 1-2 hours each day, and the rest of the time it is sleeping.

 

[AlanSubie4Life]

Interesting reading.
2021 LR.
I’m in the UK and daytime temperatures are typically 0 - 5°C at the moment (approx 35-40 F) and my car is consistently losing about 5% of its charge while I’m at work. Perhaps 8-9 hrs today dropped it from 63->58%.

I have sentry mode off, I’ve change the master account password within the week and have no 3rd party apps.

Seems a lot of people are in the same boat

That would be unusual. The key thing here is to check whether the car is sleeping. In the Apple iPhone widget (if you have an iPhone) it's pretty easy to tell if it's sleeping. (It will say it is Asleep, and unlike opening the app, it won't wake the car if it is.)

Note that (last I checked) the widget doesn't automatically update every time the car does wake up. So it doesn't accurately tell you the last time the car woke up. It just tells you the last time it got updated. But it reliably will indicate whether the car is sleeping, and will not force it to wake up.

If you check 3-4 times through the day and the car is asleep every time, the behavior you observed can't be easily explained.

If the car is always awake (will say "Parked"), then you have to fix that problem. The car should be asleep nearly all the time. There are a variety of features that keep it awake (cabin overheat protection (should not be an issue at this time), waiting for a software update, running Sentry, etc. - but you say you're not doing any of those).

But first check to make sure it's sleeping. (It's almost certainly not.) If it IS sleeping, this could be a rebalancing phenomenon, etc. (it's not easy to explain why, but some people do observe this sort of behavior and there's no easy fix - and perhaps it is nothing to worry about, as sometimes, at other SoCs, you will maybe gain a few % instead, so it all balances out).

A battery that cools will lose available energy too, which is also not a source of concern since it will come back. That's possible too. But 5% at these SoCs and temperatures seems a bit high for that (large losses would show as a blue snowflake). And I'm not even clear on how that energy loss will be represented as a % - it will change the rated miles, but in theory it changes the nominal full pack too so maybe % doesn't change as much? I don't use % nor do I live in a cold climate so I'm out of my depth on this front. Really have no idea what happens at these temperatures, for the most part. Just occasional experience. Anyway, for above freezing, 5% due to temperature alone just seems a bit high.

 

[Chrisgillett]

That would be unusual. The key thing here is to check whether the car is sleeping. In the Apple iPhone widget (if you have an iPhone) it's pretty easy to tell if it's sleeping. (It will say it is Asleep, and unlike opening the app, it won't wake the car if it is.)

Note that (last I checked) the widget doesn't automatically update every time the car does wake up. So it doesn't accurately tell you the last time the car woke up. It just tells you the last time it got updated. But it reliably will indicate whether the car is sleeping, and will not force it to wake up.

If you check 3-4 times through the day and the car is asleep every time, the behavior you observed can't be easily explained.

If the car is always awake (will say "Parked"), then you have to fix that problem. The car should be asleep nearly all the time. There are a variety of features that keep it awake (cabin overheat protection (should not be an issue at this time), waiting for a software update, running Sentry, etc. - but you say you're not doing any of those).

But first check to make sure it's sleeping. (It's almost certainly not.) If it IS sleeping, this could be a rebalancing phenomenon, etc. (it's not easy to explain why, but some people do observe this sort of behavior and there's no easy fix - and perhaps it is nothing to worry about, as sometimes, at other SoCs, you will maybe gain a few % instead, so it all balances out).

A battery that cools will lose available energy too, which is also not a source of concern since it will come back. That's possible too. But 5% at these SoCs and temperatures seems a bit high for that (large losses would show as a blue snowflake). And I'm not even clear on how that energy loss will be represented as a % - it will change the rated miles, but in theory it changes the nominal full pack too so maybe % doesn't change as much? I don't use % nor do I live in a cold climate so I'm out of my depth on this front. Really have no idea what happens at these temperatures, for the most part. Just occasional experience. Anyway, for above freezing, 5% due to temperature alone just seems a bit high.

Thanks for you thoughts. I worked from home today and interestingly the car only lost 2% over 9 hours after I unplugged for this experiment.
I wonder if after driving the car for an hour, then as the battery cools it loses charge? i’m back at work tomorrow so I will try again.

 

[AlanSubie4Life]

Thanks for you thoughts. I worked from home today and interestingly the car only lost 2% over 9 hours after I unplugged for this experiment.
I wonder if after driving the car for an hour, then as the battery cools it loses charge? i’m back at work tomorrow so I will try again.

Just check to be sure it's sleeping nearly all the time at work. That's step 1. Just be sure to check it without waking it (via the widget, which AFAIK is only available with Apple).

2% is a lot for 9 hours, in general.

Keep in mind that true "loss per hour" measurements can only be conducted over the course of 5-6 days without any use of the vehicle or waking it up (no opening the doors, etc.). That way any initial transients (may be positive or negative, you can gain miles) can be neglected. You definitely will lose a LOT of energy by opening the door at this time of year unless you're deliberately trying to avoid it.

But in any case your numbers still seem high even for short measurements.

 

[MarsOrBust]

How do yo check it via the Apple widget?
Do you mean the Tesla App?
I thought if I open the Tesla app it wakes up the car for the data.

 

[AlanSubie4Life]

How do yo check it via the Apple widget?
Do you mean the Tesla App?
I thought if I open the Tesla app it wakes up the car for the data.

Yes, opening the app will tend to wake the car. The widget is available via the standard Apple widget interface. You may need to enable the widget. Use widgets on your iPhone and iPod touch

Notes on widget:
1) It will not wake the car unless you tell it to.
2) If it says parked, your car is in idle mode, and all data is current.
3) If it says Asleep, then your car is asleep, and data is out of date.
4) For the widget: the "last updated" time is NOT the time your car was last awake. It is the last time the widget updated, which is not the same thing. The widget is not necessarily updated when the car wakes up.

The exact behavior of the widget changes all the time so if some of this information is in error, I'm sorry. It's possible that it no longer works this exact way.

 

[MarsOrBust]

Thanks, added Tesla widget but it does not let me change the widget size nor location.
It no appears in the bottom at full screen width and says last updated a few days ago?

How do you get current state instead of a few days ago?

 

[AlanSubie4Life]

Thanks, added Tesla widget but it does not let me change the widget size nor location.
It no appears in the bottom at full screen width and says last updated a few days ago?

How do you get current state instead of a few days ago?

Size and location, you'll have to refer to Apple's webpage. (It's definitely a bit more complicated, with additional functionality, in the new OS.)

That is answered above, most likely. It will update when your car is awake, but only if the app is open.

Note well what I'm suggesting this be used for: I'm not suggesting this be used to determine the current state of your miles. I'm suggesting that you use it to determine whether your car is asleep.

I have yet to see a time where the widget says the car is asleep, when it is not. If the car is awake, and you look at the widget, the widget will reflect that ("Parked"). Similarly, if the car is asleep, the widget will reflect that.

The widget will not reflect the miles/% for the car correctly unless the car is awake.

Play around with it, see if it is useful for this purpose. As I said above, the behavior has changed over time, so that means that it's possible that it may not update reliably when the car is awake (which would make it useless for this purpose). It definitely used to work this way, but I haven't paid close attention to it for months.

 

[brulaz]

When I changed my 12V battery, I shut down from the screen and the car stayed shutdown until I got the new battery hooked up. It did automatically boot as soon as the new battery was in the circuit, but it stayed shut down until then, even with the old battery still connected.
...

Possible M3 owner here. For long term storage, 2-3 months say, can you do the shutdown and disconnect the 12V battery?
That's basically what I do with my ICE car when there's no plug available.

 

[JCtx]

That's a good question, but to shut-down/remove the 12V battery, you need to shut down the battery pack first, by removing the connector under the passenger seat, meaning you'd have ZERO contact with the car. You might be fine if you charge the battery to 90%, and leave it dormant for 3 months, but that's not the ideal way to deal with storage. The best way would be to leave car connected to a 115V outlet, with charge limit at 60%, which is reportedly the ideal charge level to avoid degradation (or to minimize it), and leave the car connected all the time. Curious what the experts say .

 

[Zoomit]

That's a good question, but to shut-down/remove the 12V battery, you need to shut down the battery pack first, by removing the connector under the passenger seat, meaning you'd have ZERO contact with the car. You might be fine if you charge the battery to 90%, and leave it dormant for 3 months, but that's not the ideal way to deal with storage. The best way would be to leave car connected to a 115V outlet, with charge limit at 60%, which is reportedly the ideal charge level to avoid degradation (or to minimize it), and leave the car connected all the time. Curious what the experts say .

I'm no expert, but need to jump in and say that the documentation that Tesla provides to the EPA (example here) says:

08.03.02 Self‐discharge information
The self‐discharge rate of the High Voltage battery is likely to be less than 0.5% per month.

17.05.02 Information on safe handling of battery system
STORAGE
To maintain service life, the battery pack should be stored at a state of charge (SOC) of 15 to 50%.
​

The easy thing to do is to set it to 50% and plug it in.

 

[JCtx]

Interesting. I read that the current Tesla batteries' ideal charge level was 60%. I can believe 50%, but 15%? That makes no sense, but who knows. I'd NOT do that. Ha ha. I'm charging to 70%, and letting it discharge around 50%, before repeating the cycle... but we're using the car. I'd leave it connected between 50 and 60%. There's NEVER going to be a consensus on any of that, so new owners like myself need to read a lot, and kind of get the average of all suggestions. That's what I did .

 

[brulaz]

Unfortunately our condo parking has no plugin. Despite our repeated requests.
So that leaves the unplugged storage issue when we fly off. Zero contact is not an issue as there's no cell service 3 floors underground anyway. And 0.5% loss per month certainly would work.

So maybe charging to ... 70%? at our local supercharger, parking and pulling the connector, and removing the neg lead on the 12v would work for 2-3 months storage?

 

[Zoomit]

Unfortunately our condo parking has no plugin. Despite our repeated requests.
So that leaves the unplugged storage issue when we fly off. Zero contact is not an issue as there's no cell service 3 floors underground anyway. And 0.5% loss per month certainly would work.

So maybe charging to ... 70%? at our local supercharger, parking and pulling the connector, and removing the neg lead on the 12v would work for 2-3 months storage?

If it was me, I'd charge it to 50%, pull the HV battery connector (not sure exactly what that entails), remove the 12v battery and put that on a trickle charger for the duration. I'd also over-inflate the tires to reduce the possibility of flat-spotting them.

I don't think you can open the frunk without a 12v battery installed, so you'd need to figure out a way to keep the frunk from being closed. You need that open so you can put the battery back in, so you can open the car doors. This strategy requires more research to ensure you do the right thing and not just lock yourself out of the car. I'm positive it's been covered elsewhere on the forum though.

 

[Iain]

Sorry if this has been explained in other posts. I park at O'Hare Airport while traveling and over the past month for each trip, when I come back my car has lost 15-25 miles charge for each day I'm gone. I'm getting concerned that for a long trip, I'll come back to a car that has not enough range to drive home. Any thoughts are greatly appreciated!

I left my car at DFW for three weeks. I left it at 70% but I turned off Sentry mode and overheat protection. I also didn't check in on my car very often, perhaps once a week. It was the first time ever leaving and I was concerned, but in the end I lost 1% of charge.

I wanted to leave Sentry on but decide I lived for decades without it. I also took my time and found a fairly safe spot to park where the lanes were wide and the change of door dings was not a concern.

 

[brulaz]

Yes, with only 0.5% loss per month, a 50% charge should be fine.
Apparently you can open the frunk with a 9-12v battery via a small port in the front of the car. It's described in the manual I downloaded.
Beginning to think an M3 LR would work for us. There may be a few complications in the extreme cold, but as long as we're prepared, I think we can work around them.

 

[JCtx]

Unfortunately our condo parking has no plugin.

Based on the latest info I've read (quite a bit), what I'd LIKE to solve your 'problem' this way: Leave battery charged at 60%, disconnect rear seat connector (contactor), close all windows and doors, lock car with frunk open, remove the 12V battery, close frunk, and keep 12V battery charged at home (as suggested by another member). Having said that, I don't know if you can do that, since the procedure to change the 12V battery asks you to leave 2 windows and 2 doors open. But on the other hand, if your car loses the 12V battery while locked, you can open the frunk thru the tow-hook cover (there are 2 wires in there), then jump the battery (or install one), and then you can open doors, to reconnect seat connector. So not sure which is true. Ha ha. You could give it a test try, to find out: Disconnect the seat connector, and check if you can open windows and doors with the battery still connected (you should IMO). If you do, then you'd be in business to do what I suggested . Good luck, and keep us posted on what you did.

 

[brulaz]

Thanks to Zoomit and elptxjc for all the help.

 

[Two-rocks]

OT a bit, but there is no widget option for the iPhone 12 Pro, all updates done, in the US.