HV Battery Died with 7 miles range left showing on Range display

[Evolutis]

I've had 2 instances recently where the car died (forced to a stop) even though the battery showed a few miles of range left (7 miles and 4 miles). 2022 Model Y Performance, 38,000 miles. Current max range: 279mi, 6.4% degradation. Purchased new March 2022. Battery is usually set to charge to 80% but given I drive a lot for work I sometimes set it to 100%. 19% of my charging was done at Superchargers.

12/20: 7 miles left, 50°F, was en route to a supercharger that was about 1/4 mile away.
12/07: 4 miles left, 47°F, was 0.9 miles away from home on my freeway off-ramp exit. Had to get towed.

In both cases I had the car set to navigate to the supercharger or home and the car stated I could make it to my destination. In the first few months of ownership there were a handful of occasions where I arrived home with 1 mile or 0 miles left. The vehicle did not slow down dramatically or display messages that it was going to run out of range.

Has anyone else had this experience where the car is dying with 4+ to 7+ miles range left? Is there anything that can be done in a service appointment? For example, can a technician do a recalibration such that the estimated range shown is more accurate? I understand that taking the battery to a low SOC is not good for it's health however that's not my question. Since both instances, I've taken steps to ensure I arrive at my destination with more range but I'm losing a bit of trust / confidence in the stated range. Will it get worse over time? For example in the future is the car at risk of dying with 10 miles left, 15 miles left?

 

[fiehlsport]

I think most Tesla owners will report that they can go this low, or lower, without issue. Even 0mi indicated should still be drivable, using the hidden buffer at the bottom. Something is off with this one. I've reliably gone down to 2mi a few times without worry.

This might be one of those times where an overnight battery calibration at various SoCs would be useful - i.e. Keep the car at 20% for 24 hours, then 50%, then 80%, rather than charging it to 80% every single day. (Maybe on a weekend if possible, since it looks like that wouldn't be feasible during the week for you)

It's not a degradation issue, it's likely to be that the battery doesn't know how much energy it *actually* has at SoCs other than 80 or 100%. And I wouldn't worry about harming the battery by going this low, it's not like you're storing it at 3% for a week.

Is your 2022 an Intel or Ryzen car? (12v or 15v Li-Ion LV battery)

Try this:

"Do not charge the car every night. Leaving the car at different states of charge, across a broad range, helps provide a spread of readings. Even once a month, at a SoC below 50% can help."

Tesla battery management system (BMS) calibration

Tesla battery management system (BMS) calibration instructions

tesla-info.com

 

[exxxviii]

I've had 2 instances recently where the car died (forced to a stop) even though the battery showed a few miles of range left (7 miles and 4 miles). 2022 Model Y Performance, 38,000 miles. Current max range: 279mi, 6.4% degradation. Purchased new March 2022. Battery is usually set to charge to 80% but given I drive a lot for work I sometimes set it to 100%. 19% of my charging was done at Superchargers.

12/20: 7 miles left, 50°F, was en route to a supercharger that was about 1/4 mile away.
12/07: 4 miles left, 47°F, was 0.9 miles away from home on my freeway off-ramp exit. Had to get towed.

In both cases I had the car set to navigate to the supercharger or home and the car stated I could make it to my destination. In the first few months of ownership there were a handful of occasions where I arrived home with 1 mile or 0 miles left. The vehicle did not slow down dramatically or display messages that it was going to run out of range.

Has anyone else had this experience where the car is dying with 4+ to 7+ miles range left? Is there anything that can be done in a service appointment? For example, can a technician do a recalibration such that the estimated range shown is more accurate? I understand that taking the battery to a low SOC is not good for it's health however that's not my question. Since both instances, I've taken steps to ensure I arrive at my destination with more range but I'm losing a bit of trust / confidence in the stated range. Will it get worse over time? For example in the future is the car at risk of dying with 10 miles left, 15 miles left?

If I were you, I would change the display to show battery % instead of miles of range. You took the battery to less than 2% and were surprised that it was off by a little. You were on the very fringe of battery and calculating with precision at that level is pretty risky business. Honestly, I would never plan to go below 5% and would be stressed below 10%. I think L-ion SOC accuracy is around 1%, so you were killing it within its acceptable range of accuracy.

 

[MP3Mike]

I'm curious what was going on as it shut down? Were you going uphill? Did you accelerate to pass someone? (Putting a "strain" on the battery when it is close to empty can cause the voltage to sag below the cut-off point and shutdown when there is otherwise usable energy left.)

 

[jcanoe]

When you park your Model Y at the Home location is Sentry mode set to be Off. When Sentry mode remains active, at the Home location the Telsa Model Y cannot enter sleep mode. The Tesla Model Y's battery management system can only measure the open cell voltage (OCV) of the cells in the high voltage battery when the high voltage battery is disconnected as during Sleep mode. The OCV measurement improves the BMS's ability to accurately determine the state of charge of the battery.

 

[GtiMart]

Yep, I think both significant points are covered already:
1- the BMS might have poor calibration if you always keep your battery in the same SOC range. Make it see low and make it see full some time to time. EDIT: And let the car sleep in those situations, for multiple hours.
2- Pushing the accelerator hard when you're empty is a sure way of forcing the car to shutdown. You need to drive carefully as to not go over whatever power limit the BMS thinks applies at that low a SOC. Some youtubers have brought that up a few times, like Kyle Conner (out of spec) from memory.

 

[qdeathstar]

I've had 2 instances recently where the car died (forced to a stop) even though the battery showed a few miles of range left (7 miles and 4 miles). 2022 Model Y Performance, 38,000 miles. Current max range: 279mi, 6.4% degradation. Purchased new March 2022. Battery is usually set to charge to 80% but given I drive a lot for work I sometimes set it to 100%. 19% of my charging was done at Superchargers.

12/20: 7 miles left, 50°F, was en route to a supercharger that was about 1/4 mile away.
12/07: 4 miles left, 47°F, was 0.9 miles away from home on my freeway off-ramp exit. Had to get towed.

In both cases I had the car set to navigate to the supercharger or home and the car stated I could make it to my destination. In the first few months of ownership there were a handful of occasions where I arrived home with 1 mile or 0 miles left. The vehicle did not slow down dramatically or display messages that it was going to run out of range.

Has anyone else had this experience where the car is dying with 4+ to 7+ miles range left? Is there anything that can be done in a service appointment? For example, can a technician do a recalibration such that the estimated range shown is more accurate? I understand that taking the battery to a low SOC is not good for it's health however that's not my question. Since both instances, I've taken steps to ensure I arrive at my destination with more range but I'm losing a bit of trust / confidence in the stated range. Will it get worse over time? For example in the future is the car at risk of dying with 10 miles left, 15 miles left?

Fool me once, shame on you. fool me twice….

 

[chobra]

Fool me once, shame on you. fool me twice….

I can't even handle my phone getting to 2-7% or even under 10%

 

[GtiMart]

Yeah, shouldn't be fooled twice, but we can attenuate that comment with:
- not everyone understands that the state of charge, whether expressed in percent or miles, is just an estimate. It's just not possible to get a precise read of how much energy can be pulled out of a battery.
- not everyone understands what can be done to save energy and arrive with more (slow down) but more importantly, not everyone knows what will provoke early failure.

It's easier to not get fooled twice when you understand everything in the problem space. I would argue that showing SOC as miles gives the wrong impression that it is precise up to the mile. Maybe they should do like ICE cars and show estimated range left "in the tank" rounded to the nearest 10 or so. OR show "--" under a certain treshold

Similar for the voltage sag... they restrict output power of the battery depending on SOC but also temperature. In this particular state maybe they are overly optimistic so people hit the "cutoff". If that value were reduced further, pressing the accelerator to the max would accelerate less but might not provoke shutdown.

 

[Evolutis]

I think most Tesla owners will report that they can go this low, or lower, without issue. Even 0mi indicated should still be drivable, using the hidden buffer at the bottom. Something is off with this one. I've reliably gone down to 2mi a few times without worry.

This might be one of those times where an overnight battery calibration at various SoCs would be useful - i.e. Keep the car at 20% for 24 hours, then 50%, then 80%, rather than charging it to 80% every single day. (Maybe on a weekend if possible, since it looks like that wouldn't be feasible during the week for you)

It's not a degradation issue, it's likely to be that the battery doesn't know how much energy it *actually* has at SoCs other than 80 or 100%. And I wouldn't worry about harming the battery by going this low, it's not like you're storing it at 3% for a week.

Is your 2022 an Intel or Ryzen car? (12v or 15v Li-Ion LV battery)

Try this:

"Do not charge the car every night. Leaving the car at different states of charge, across a broad range, helps provide a spread of readings. Even once a month, at a SoC below 50% can help."

Tesla battery management system (BMS) calibration

Tesla battery management system (BMS) calibration instructions

tesla-info.com

Ryzen with Li-on LV Battery. When the car died with 4 miles left, the LV battery completely died after 50 minutes leaving my car blacked out on the side of the road.

Thank you very much for the troubleshooting tip, this is the most helpful response in this thread. I will do that.

 

[Evolutis]

If I were you, I would change the display to show battery % instead of miles of range. You took the battery to less than 2% and were surprised that it was off by a little. You were on the very fringe of battery and calculating with precision at that level is pretty risky business. Honestly, I would never plan to go below 5% and would be stressed below 10%. I think L-ion SOC accuracy is around 1%, so you were killing it within its acceptable range of accuracy.

On the most recent time it died with 7 miles left the battery showed 2% left. So if the 1% margin of error you stated is true, I'm still within that.

 

[Evolutis]

I'm curious what was going on as it shut down? Were you going uphill? Did you accelerate to pass someone? (Putting a "strain" on the battery when it is close to empty can cause the voltage to sag below the cut-off point and shutdown when there is otherwise usable energy left.)

No strain, in the first instance I was on the freeway which was flat, going about 65 to 70 mph in autopilot. A couple minutes before the car died, the max speed I could go was around 33 mph. At the very end I went on the inclined off ramp for maybe 50 feet and the car died. Even if it was flat the car would have died within a minute or 2.

In the recent instance I was in a shopping mall going 10 to 20 mph, driving conservatively during and before. Car was also hard limiting my speed at the very end. I never mashed the accelerator.

 

[E90alex]

1. Sounds like your BMS calibration is probably off

2. Seems like you need to adjust your charging habits and fit in a mid day charge instead of charging to 100% at home and running it to dead all the time.

 

[Evolutis]

When you park your Model Y at the Home location is Sentry mode set to be Off. When Sentry mode remains active, at the Home location the Telsa Model Y cannot enter sleep mode. The Tesla Model Y's battery management system can only measure the open cell voltage (OCV) of the cells in the high voltage battery when the high voltage battery is disconnected as during Sleep mode. The OCV measurement improves the BMS's ability to accurately determine the state of charge of the battery.

At home Sentry mode is always off. Thank you for the troubleshooting though.

 

[Evolutis]

Yeah, shouldn't be fooled twice, but we can attenuate that comment with:
- not everyone understands that the state of charge, whether expressed in percent or miles, is just an estimate. It's just not possible to get a precise read of how much energy can be pulled out of a battery.
- not everyone understands what can be done to save energy and arrive with more (slow down) but more importantly, not everyone knows what will provoke early failure.

It's easier to not get fooled twice when you understand everything in the problem space. I would argue that showing SOC as miles gives the wrong impression that it is precise up to the mile. Maybe they should do like ICE cars and show estimated range left "in the tank" rounded to the nearest 10 or so. OR show "--" under a certain treshold

Similar for the voltage sag... they restrict output power of the battery depending on SOC but also temperature. In this particular state maybe they are overly optimistic so people hit the "cutoff". If that value were reduced further, pressing the accelerator to the max would accelerate less but might not provoke shutdown.

I'm very aware that the displayed range is an estimate however I feel that reasoning is most applicable when the battery is at a say high or medium SOC and one is trying to forecast how far they can go. For example When I 100% charge the displayed range shows 279 miles left. I'm keenly aware that I won't get that, I may get 75% of that. In this case when the battery says I have 7 miles left when in fact I have 0 miles left, I don't think that's normal. However, that's why I'm here to ask if this is normal for other Tesla owners? Based on my experience as stated I could take the car to 1 mile left or so no problem. Not anymore.

For some added context when Edmunds did a range test on Teslas and various EVs, the teslas came up short (as measured to 0 miles displayed), Edmunds published then Tesla contacted them and said to get the true range you need to run the car past 0 until it dies. Edmunds found the Model Y went around 12 miles past 0. I'm not advocating this but it's just one more data point to have me think my Model Y dying at 7 miles, something might be off. Source: Tesla Disputed Edmunds Tests, Edmunds Did Them Again: See The Results

Also aware that driving aggressively, fast, etc hurts range, the same is true for ice vehicles. In both cases where the car died I made an effort o drive very conservatively, slowly and watch the range closely.

 

[jcanoe]

In colder temperatures the Tesla Model Y will automatically lower the estimated state of charge (SOC) by 3% after the Model Y has been parked overnight. Perhaps 50F is not cold enough to trigger the Tesla Model Y to restate the SOC as 3% lower when it probably should. It would be interesting to run the same range test when the ambient temperature was 75F to 80F.

You might want to carry a Honda portable generator for those times when you are testing the limit of the range of your Tesla Model Y. Beats waiting for a tow vehicle.

 

[Evolutis]

In colder temperatures the Tesla Model Y will automatically lower the estimated state of charge (SOC) by 3% after the Model Y has been parked overnight. Perhaps 50F is not cold enough to trigger the Tesla Model Y to restate the SOC as 3% lower when it probably should. It would be interesting to run the same range test when the ambient temperature was 75F to 80F.

You might want to carry a Honda portable generator for those times when you are testing the limit of the range of your Tesla Model Y. Beats waiting for a tow vehicle.

I do think the colder temps played a roll, that has been a common denominator in both cases where the car died.

My current solution is to charge longer at superchargers when trying to make it home after a long drive and assume 10 miles left is effectively 0 miles left.

 

[Evolutis]

Correction: The most recent time the car died was on 2/20 not 12/20, I can't edit my post.

Also I was able to find a 110V outlet and charger from 7 miles to 9 miles then drive to the Supercharger on the recent instance.

If anyone is curious I went into the service menu and snapped this pic after going from 7mi to 9mi. SOC showed 9.5%, I know this is different than the displayed range / percentage.

 

[SageBrush]

I'm curious what was going on as it shut down? Were you going uphill? Did you accelerate to pass someone? (Putting a "strain" on the battery when it is close to empty can cause the voltage to sag below the cut-off point and shutdown when there is otherwise usable energy left.)

This is my answer too. OP needs to drive manually, about 5 - 10 mph below the speed limit when the SoC is < 5% to eeek out the last bit of battery charge.

 

[ewoodrick]

If you are under 10% and too far away from the charge, I don't think that I'd route to the Supercharger, I don't want the car to even think about using energy to condition the battery (I hope that it doesn't do it anyway)

But at 10%, especially if I know that I'm barely going to reach the charger, I wouldn't be driving 65-70. That's time to get off the Interstate and start doing 40mph or less.

Your location indicates California, I'll guess that even may be in one of those areas that Superchargers all over the place. Take advantage of it. Stop and add just 10 minutes in the middle of the day.

Running your battery down to less than 10% multiple times isn't great on the battery.
It's the same with ICE vehicles, there too much possiblity you going to suck up water in the tank.
Don't run the car that close to 0.

Will the car get worse? I doubt if anyone really knows, And probably won't unless some YouTuber wants to go out and do something stupid, (as they commonly do).

Stop beating your head against the wall, it will hurt less.