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

[voip-ninja]

The energy graph is only based on your last 5, 10, 30 miles. With a possible 10% loss you are going to have to do one long continuous drive of at least 90% to even have a chance of nailing the loss down as actual loss.

Edit, and if you think the range loss coincides with a FW update, then it is even more unlikely that it is REAL loss, unless you are suggesting that the FW bricked part of your pack.

I'm wondering if the FW changed the way the BMS estimates the range. Who knows.

I can't do a 2-3 hour drive to run the battery down and get the "real" range (a.k.a, Bjorn's method) because I have young children, there is no time for dad to run out and do a multi-hour road trip as an experiment.

I see a lot of people report that after newer FW updates their range dropped by maybe 10 miles. Mine has dropped by about 26 miles.

 

[Krazaak]

Since the energy graph consistently shows my estimated range at even less than the display range I am left to conclude that the range loss in my car is real. Perhaps I have a pack that is affected with premature loss of some of the cells or something similar. Only Tesla knows and they aren't telling me anything.

I'm not sure what you mean by that. The projected range and rated range both use the same base information (kWh available) and then provide either rated range (based on the rated Wh/mi) or projected range (based on actual Wh/mi over last 5, 15, 30mi). Projected range is obviously going to fluctuate as your actual efficiency varies, but they're both going to decrease at the same base ratio.

I think you're going to be hard pressed to get Tesla to investigate because even if you do demonstrate an actual 10% battery loss in year 1, it isn't going to trigger a warranty claim. If long term residual value is your concern, then worry about long term battery degradation. If your degradation flattens out then you'll end up the same place as everyone else in a few years, if it continues as steeply, you'll trigger replacement under warranty.

 

[derotam]

I'm wondering if the FW changed the way the BMS estimates the range. Who knows.

I can't do a 2-3 hour drive to run the battery down and get the "real" range (a.k.a, Bjorn's method) because I have young children, there is no time for dad to run out and do a multi-hour road trip as an experiment.

I see a lot of people report that after newer FW updates their range dropped by maybe 10 miles. Mine has dropped by about 26 miles.

Put em in the car! Haha. I understand, I have a 5 and 2yr old....there is always a way though!

 

[Atari2600]

Does anyone know if you can graph the battery report based on date instead of odometer? If I could do that I could show my firmware update report and compare it directly to the battery report. You can see I charge at either 80 or 90 percent. I've read that charging to 90 in the hot summer might be a bad idea but in the winter it is fine so I am switching to that plan.. not to mention I can use more battery in the winter. You can see on my battery report I had 308 miles at 12,590 on my odometer so I think it probably is firmware. I guess I could download raw data and make my own battery report graph.

 

[voip-ninja]

I think you're going to be hard pressed to get Tesla to investigate because even if you do demonstrate an actual 10% battery loss in year 1, it isn't going to trigger a warranty claim. If long term residual value is your concern, then worry about long term battery degradation. If your degradation flattens out then you'll end up the same place as everyone else in a few years, if it continues as steeply, you'll trigger replacement under warranty.

You are right, I'm not a YouTube celebrity (Like Tesla had a similar problem and got Tesla engineers to powder puff her car and figure out what was going on, blamed it on charge pattern, reset the BMS and probably worked other magic) so Tesla is just going to blow me off.

There are others with similar range dips and Tesla has pretty much told them "normal" so I guess I'm likely stuck.

If the pack continues to degrade it's not a whole lot of consolation knowing that somewhere down the road Tesla may or may not replace the battery. If I decided to sell the car in a couple of years time the accelerated degradation of my car would cost me thousands of dollars. Obviously if there is a real loss in range it causes the additional problem of not getting full usage out of the battery for road trips or longer days of driving, more charging stops, etc.

 

[scubastevo80]

I'm wondering if the FW changed the way the BMS estimates the range. Who knows.

I can't do a 2-3 hour drive to run the battery down and get the "real" range (a.k.a, Bjorn's method) because I have young children, there is no time for dad to run out and do a multi-hour road trip as an experiment.

I see a lot of people report that after newer FW updates their range dropped by maybe 10 miles. Mine has dropped by about 26 miles.

I bought my LR AWD is Oct of last year and we saw some decrease on the Stats app (305 miles) through the first 7k miles of use in Oct through March, the colder months. Then, in April from about 7k-9k miles I was back at 308-309 range. At the 9k mark in mid-June, after installing one of the 2019.20.x firmware updates, my range dropped to about 300 and has been trending downward since. I'd expect a lower range algo if my wh/mi figures were poor as they are in winter, but not in the summer where I'm averaging 225wh/mi or so.

I realize this is obviously not the end of the world, but I relate this to a suspected oil or headgasket leak on a gas car. Is there a real problem and is it going to get worse? Not having real information is frustrating. I can check for an oil leak, I can't check for real battery degredation. We have two Teslas and my wife drives much more than I do so she often charges in the garage on weekdays. Prior to the June update and now v10, I could charge to 80% on Sunday night and not have to charge my car again until the following weekend. Now, between real/imagined range loss and some of the phantom drain I've experienced with v10, I'm back to changing my charging habits so that I charge almost daily with a lot of car swapping at night and in the morning.

 

[voip-ninja]

I bought my LR AWD is Oct of last year and we saw some decrease on the Stats app (305 miles) through the first 7k miles of use in Oct through March, the colder months. Then, in April from about 7k-9k miles I was back at 308-309 range. At the 9k mark in mid-June, after installing one of the 2019.20.x firmware updates, my range dropped to about 300 and has been trending downward since. I'd expect a lower range algo if my wh/mi figures were poor as they are in winter, but not in the summer where I'm averaging 225wh/mi or so.

I realize this is obviously not the end of the world, but I relate this to a suspected oil or headgasket leak on a gas car. Is there a real problem and is it going to get worse? Not having real information is frustrating. I can check for an oil leak, I can't check for real battery degredation. We have two Teslas and my wife drives much more than I do so she often charges in the garage on weekdays. Prior to the June update and now v10, I could charge to 80% on Sunday night and not have to charge my car again until the following weekend. Now, between real/imagined range loss and some of the phantom drain I've experienced with v10, I'm back to changing my charging habits so that I charge almost daily with a lot of car swapping at night and in the morning.

I believe that diagnostically Tesla is able to look at the real pack voltage level at specific charge levels and make a determination of the real health of the pack. This is why I asked them (I was ignored) for a battery health report that might include some of this info.

You are right, it is not the end of the world and of course there is going to be some pack variation, but you would expect nearly all samples of the pack to conform pretty tightly to a norms graph on the degradation based on a variety of things.

It is indeed frustrating to be guessing about what is going on.

Luckily for me most of my use is for commuting. Even if the pack continues this accelerated decline it won't leave me stranded any time soon but it might change how I use the car for longer trips and might also determine if I trade/sell it for another Tesla product in the future.

 

[voip-ninja]

okay so my local SA came through for me, at least insofar as sending a ticket in to have the health on the pack pulled up to check it out. We'll see what they have to say about it.

 

[0mpg]

im interested to see what they say

 

[Cmunny]

I'm in this boat, too.

I woke up a few weeks ago preparing to evacuate for Hurricane Dorian. First thing I did was check my range, which I charged to 90% that night. At 7 am it read 212 miles at 90% (still SR+ capacity). I set it to charge to 100% while I made breakfast and packed.

45 minutes later I got in my car to find the charging was complete at 100% with only 208 miles. The software limit was installed while I packed to evacuate, despite Musks assurances that evacuees would have limits removed during evacuation. AND the total range was only 208 miles.

I called Tesla Service and they said nothing was wrong, try to recalibrate (drive below 20%, charge to 100%). So. I did that twice while on evacuation. The second time, my range dropped to 207.

Called Tesla Service again and was told to keep recalibrating and it will eventually return my lost range. So I did it two more times over the next two weeks. Both times I lost another mile of range.

So now I'm at 205 miles at 100%.

Called Service again to set up an appointment and they informed me that there is nothing wrong according to their OTA diagnostics, and that it is normal battery degradation.

But to lose almost 6% capacity at the very moment the software limit was imposed doesn't suggest normal degradation, does it? Then to have it continue to lose another 1% while following Teslas recommendation.

They cancelled the service appointment, saying bringing it in would not be helpful.

I insisted they escalate my issue to Engineering for further attention.

I love this car so much, but this is breaking my heart. If I lose much more range I will not be able to take my car on road trips.

 

[Cmunny]

I should note:

Took delivery on April, 2019. 8172 miles.
Lifetime average 336whpm
Daily commute of 30 miles, average 202whpm
Supercharged 6 times
Charge daily from 75% to 90%.

 

[Cmunny]

Correction: average lifetime 236whpm

 

[MarcG]

I’ve experienced a similar drop in range, but mine started with 2019.28.3.1 and has continued to nosedive with 2019.32.11.1
Haven’t paid much attention to the Wh/mile consumption as I don’t have a regular commute (I bike to work) but will check on my next raid trip

 

[UltralightBeam]

I've submitted one range issue as a bug report but not sure if I'd get a response...

 

[hlin07]

I should note:

Took delivery on April, 2019. 8172 miles.
Lifetime average 336whpm
Daily commute of 30 miles, average 202whpm
Supercharged 6 times
Charge daily from 75% to 90%.

First thing I'd do is change your daily charge to 80%, only charge higher when you need the range say going on a trip. While Elon stated it's probably fine to go to 90%, battery science tells us 80% is better than 90% long term.
205 miles at 100% is concerning. Do you see the same 15 miles less at 90%? 80%? Meaning 220*0.9-15=183, etc.

 

[Cmunny]

Yes, I do. Charging to 90% (which is 80% of the software limited SR+ battery capacity) leaves me with 182 to 184. Once I only had 178 at 90%, but that seems to be a fluke.

 

[kel8kel]

Yes, I do. Charging to 90% (which is 80% of the software limited SR+ battery capacity) leaves me with 182 to 184. Once I only had 178 at 90%, but that seems to be a fluke.

i have the same problem as you. SR+ and my 100% range is at 209, sometimes down all the way to 202. Also scheduled an appointment and Tesla says that everything seemed nominal and it was normal battery degradation. I live in Southern California.

Losing ~15% range within the first 6 months is extremely worrying...

 

[Cmunny]

I would worry less if I could get Tesla to even aknowlege that there is a problem. But until it loses 30% capacity, they say they can't do anything.

I have had several technicians, some over chat and some on the phone, claim it was my car adjusting to my driving habits. Problem is, Teslas don't do that. They show rated range, not habitual range. They seem to be gaslighting to get me to stop looking into it.

 

[voip-ninja]

I got a reply from my local SC adviser and am probably more confused now than before. He reports my battery is fine but that my battery is showing low because I don't discharge the battery to 20% before plugging it back in.

Huh?

I thought "a plugged in Tesla is a happy Tesla".

Yes I had the vehicle reviewed and the the reason you are seeing this is algorithm related. No trouble with the battery. We can see that the battery on your vehicle doesn't drain very far before being plugged to charge up. To get a more accurate reading you can deplete the charge of your battery further before plugging in to charge. Usually plugging in at about the 20% mark should help the system get a better estimate, but it is just that, an estimate. There are simply too many variables involved to accurately predict the range in miles which is usually why my techs and I advise to not use it but rather switch that display to battery percentage instead.

 

[Atari2600]

I got a reply from my local SC adviser and am probably more confused now than before. He reports my battery is fine but that my battery is showing low because I don't discharge the battery to 20% before plugging it back in.

Huh?

I thought "a plugged in Tesla is a happy Tesla".

Do you want a happy Tesla or happy battery guage? They are not necessarily the same.