Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[mangrove79]

There are several threads that talk about how to recover some of that "lost" range - basically once in a while you want to charge to 100%, and drive it down to under 10% over the course of a few days, allowing the car to sleep for an extended period of time (nightly) so the range can be recalibrated. Mine dropped from 326 to 315 after 6 months (before I read about this technique). When I tried it the first time, it went back to 321. After the 2nd time (a month later) I got back to 326.

 

[Tam]

P.S.: I don't know if it has LFP batteries or not.

If your charging screen in your car (not in your phone app) shows "Daily" and "Trip", that is not LFP:

If your charging screen in your car (not in your phone app) is lacking "Daily" and "Trip", that is LFP:

 

[Tam]

Is this normal? Is it worth making a service request?

There's not much you can do until your car can only hold less than 70% of the EPA capacity. Tesla gives you a buffer of 30% loss so you don't have to be worried when you only lost 13 miles. There are still many more miles to lose before you reach a 30% loss.

The fluctuation is most likely from the BMS, battery system management: It tries to do its best to guess how much capacity your battery has.

You can aid the BMS accuracy by:

If it is the traditional Lithium pack, set your charge setting at 90%.

If it is the LFP pack, set your charge setting at 100%.

If you are still worried, have Service Center check it for you.

If I were you, I would just enjoy my Tesla as long as I have 70% capacity of the EPA number.

 

[gabrielschulho]

There are several threads that talk about how to recover some of that "lost" range - basically once in a while you want to charge to 100%, and drive it down to under 10% over the course of a few days, allowing the car to sleep for an extended period of time (nightly) so the range can be recalibrated. Mine dropped from 326 to 315 after 6 months (before I read about this technique). When I tried it the first time, it went back to 321. After the 2nd time (a month later) I got back to 326.

Thank you for your answer! So, is the loss of range just a calibration error? I guess that means the battery hasn't actually lost capacity, but the car is refusing to exploit that capacity, because it's (mistakenly?) calculated that the capacity is lower than it really is, right?

How do I allow the car to sleep? Do I simply not plug it in, or is there something special I need to do in addition to not plugging it in?

 

[mangrove79]

Thank you for your answer! So, is the loss of range just a calibration error? I guess that means the battery hasn't actually lost capacity, but the car is refusing to exploit that capacity, because it's (mistakenly?) calculated that the capacity is lower than it really is, right?

How do I allow the car to sleep? Do I simply not plug it in, or is there something special I need to do in addition to not plugging it in?

Yes, your range number is ALWAYS an estimate - of how much capacity you have in your battery at that moment. So, the accuracy of the calibration plays an important role. Occasional recalibration will help it get back "on track" so to speak. As for sleeping, I think it should be the default behavior as long as you don't have sentry mode turned on (at home at least), or anything that keeps the car awake all the time. If you want to be sure, you can always go Control > Safety > Power off when you're done driving for the day.

 

[hanswiththe3]

Did you get a new battery? Also, Supercharging wouldn't cause that problem. Its actually generally very safe for the battery with the end result being slightly higher degradation vs. at-home level 2 charging.

Yes, they replaced my HV Battery. The car could not charge before. Not sure why it happened then! I did supercharge like 5 times a week though for like 8 months.

 

[Apprunner]

Yes, they replaced my HV Battery. The car could not charge before. Not sure why it happened then! I did supercharge like 5 times a week though for like 8 months.

That still wouldn't kill the HV battery. Just a faulty battery. You probably did have slightly elevated degradation though.

 

[conv90]

Did you let the car sleep at that low SOC?
I think the key point is to let it sleep, to show the OCV to the BMS.
If the OCV is higher than expected, the BMS ”finds” the lost energy.

If the OCV is below 3.2V, the span of uncertiness of the SOC is reduced quite much. ( The voltage climbs when the battery is at rest so its needed to aim below when the car is awake, 3.0 to 3.1V or so.)

By the way, what cell voltage did you have at -1.56% ?

I made this try not for a particular purpose of Range recovery . so I have saved very little SMT screen.
When It was still fresh in my mind I've posted here in this Thread or somewhere in the TMC.
I remember of som 3.050 mv somewhere but I don't remember if in motion or in P . I have started the charge right after I reached the -2,32% SoC.

 

[conv90]

Probably the battery would have shut itself down, though it may have been premature. Hard to know.

Anyway, if you get another opportunity, monitor both the start and end on SMT and ALSO monitor trip consumption (also zero the trip meter just in case you do have to stop (briefly!), which messes up the experiment, but if it is real quick with minimal time spent in park it might not be too large an error).

I don't know if I have the time to do a similar test. I could try if i find a day when I'm at 30-35% Soc and only 150-170 km left. Driving only to consume battery is not fun if you know that you have to end near a charger.
the battery continue to recover:
Yellow is when I performed the sub 0% test and Green is today

 

[Steve446]

I don't know if I have the time to do a similar test. I could try if i find a day when I'm at 30-35% Soc and only 150-170 km left. Driving only to consume battery is not fun if you know that you have to end near a charger.
the battery continue to recover:
Yellow is when I performed the sub 0% test and Green is today
View attachment 803010

Wow ~+6.3% is very large !

 

[AlanSubie4Life]

I don't know if I have the time to do a similar test

Yeah, really only makes sense if you're already doing some sort of road trip. And to be clear I'm not suggesting driving all the way into the buffer - even though that would mean that the results would not be definitive, at least it would give you an idea of whether the energy was even possibly "really there." If it wasn't, it would be pretty clear before you get to 0%, since you're talking about a 5% difference here.

 

[AAKEE]

I made this try not for a particular purpose of Range recovery . so I have saved very little SMT screen.
When It was still fresh in my mind I've posted here in this Thread or somewhere in the TMC.
I remember of som 3.050 mv somewhere but I don't remember if in motion or in P . I have started the charge right after I reached the -2,32% SoC.

I have a slight memory of seeing that picture.

I had 2.980 to 3.006 V, average 2.993V when the car had been sleeping for a couple of hours at 0.13% SOC, battery temp 16C,and battery power 0.40kW.
( stopped driving at average 2.843V)

Seeing higher voltage at lower SOC implies the BMS is off compared to mine. No guarantee mine is correct.

 

[scampy74]

Hi all,

New Tesla owner here; just bought my 2020 M3 SR+ with 9500 miles on it. I'm noticing that even at 100% charge the maximum range showing on my SR+ is 223. If I charge to 85% I only get 185 miles. Currently the car shows 73% battery, with 165 miles in range.

Is this a normal amount of battery loss? Online I'm seeing that the 2020 SR+ should have 263 miles of range, and everything I'm seeing says to expect 3% loss per 10k miles. So I'd expect it to be around 255 miles in range currently at full charge (give or take a bit), based on the miles on the car.

Just wanting to confirm if my thought process is correct before I schedule to take the car to service center to have the battery packs looked at.


Thanks!

 

[Sophias_dad]

Have you been regularly charging to 100%? Leaving it charged at 100%? That is a bad idea with a 2020 and before, and some 2021's.

You've lost 15% of the battery's capacity, and that's only a reported/estimated number. The service center probably won't even make an appointment for you.

 

[MP3Mike]

I'm seeing that the 2020 SR+ should have 263 miles of range,

I'm showing it started at 250:

 

[scampy74]

Thanks for the replies. I had just ran a search on Google to see the 263 miles. Even at 250 miles, 223 would indicate a ~11% decrease over 9500 miles.

As for the charging, I just bought the car last week. I've only been charging it to 85% personally, letting it get down to 30-40% before recharging. I can't speak to how the previous owner charged it, so I'm unsure if they routinely kept it at 100%. Is there a way for me to tell that in the diagnostics within the car itself? Still getting used to where to find everything related to the car.

 

[mangrove79]

Thanks for the replies. I had just ran a search on Google to see the 263 miles. Even at 250 miles, 223 would indicate a ~11% decrease over 9500 miles.

As for the charging, I just bought the car last week. I've only been charging it to 85% personally, letting it get down to 30-40% before recharging. I can't speak to how the previous owner charged it, so I'm unsure if they routinely kept it at 100%. Is there a way for me to tell that in the diagnostics within the car itself? Still getting used to where to find everything related to the car.


View attachment 803330

I think the "official" range for a 2020 SR+ is 263, but some sites report that EPA real-world testing (whatever that is) yielded 250 miles at the most. Either way, 223 mi after less than 10K is way too much loss.

Nothing wrong with your charging habits. That's similar to what I do. I posted a way to recover some of those lost ranges above, post #4,761. That's if the previous owner never did that. If so, you might be able to recover some of that lost range. If the previous owner had done this regularly in the past, then it won't work as well.

 

[conv90]

Thanks for the replies. I had just ran a search on Google to see the 263 miles. Even at 250 miles, 223 would indicate a ~11% decrease over 9500 miles.

As for the charging, I just bought the car last week. I've only been charging it to 85% personally, letting it get down to 30-40% before recharging. I can't speak to how the previous owner charged it, so I'm unsure if they routinely kept it at 100%. Is there a way for me to tell that in the diagnostics within the car itself? Still getting used to where to find everything related to the car.


View attachment 803330

You can install Scan My Tesla and you can (at least) see how many kWh have been charged with DC (Supercharger or Fast chargers) and with AC in the history of the car.

 

[MRLR]

I went through like 100 pages of this thread but I’m still confused as to exactly how to charge my Tesla to keep the lowest battery degradation.

I just purchased a M3LR - 358 miles. I got it last Friday. And so far I’ve charged it 4x. First initial charge was to 90% ever since kept at at 80%. Thinking to lowering to 75%.

What is the best way to charge this?

Every other day?
Everyday 10-20% charge couple hours?
Let it die to 20% or 30% and then charge it?

i try to stay away from superchargers and mostly just use Level 2 or anything less than 50kwh. my work is 7kwh and it’s free so a huge win there.

 

[Bouba]

I went through like 100 pages of this thread but I’m still confused as to exactly how to charge my Tesla to keep the lowest battery degradation.

I just purchased a M3LR - 358 miles. I got it last Friday. And so far I’ve charged it 4x. First initial charge was to 90% ever since kept at at 80%. Thinking to lowering to 75%.

What is the best way to charge this?

Every other day?
Everyday 10-20% charge couple hours?
Let it die to 20% or 30% and then charge it?

i try to stay away from superchargers and mostly just use Level 2 or anything less than 50kwh. my work is 7kwh and it’s free so a huge win there.

We are all in the same boat! The general opinion of the forum battery gurus (and I am most grateful to them) is keep it plugged in all the time...but only put the minimum amount of charge that you need...and time it so that it charges just before you drive it. For me I’ve interpreted that to mean 55% (just below the level that causes real damage) but still gives me 300 kilometers in the tank