I wanted to make sure of the battery usage. We actually took a picture of the screen when we broke down because we knew people wouldn't believe us. The WH/m was 360 Wh/m which was higher than normal but still doesn't justify us breaking down with the car saying we had 16 miles left on the range. I hope the same doesn't happen to you someday.
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Infinite Mile Battery Warranty [Now] Being Honored By Tesla [Issue Resolved]
- Thread starter HMARTINPT
- Start date
I think Tesla is unreasonable in citing "battery degradation."
I've heard quite a few cases like yours and they all got their battery replaced under 8 year battery warranty.
The latest one is documented in:
Battery runs out with 16% indicated range remaining
If you have TM-Spy your report might show uneven voltages and not nicely even as below:
Each bar represents a brick. There are 96 bricks and each brick has 74 cells for a total of 7,104 cells. These bricks are in parallel so there's no sweat if one single cell fails.
However, If there are enough cells fail, it can create unbalanced charging and eventually would pull the whole pack down.
That is a pack failure and not degradation.
Failure to hold a charge is not the same as degradation.
I don't think a case where a battery shuts down at 16 percent is really like a case where the battery shuts down at 16 miles. Big difference.
A single cell failing brings down the entire pack by more than 1%! Why? Because now the entire battery capacity is limited by the one brick that has lost the cell. When discharging, you have to stop when the brick with the lost cell is empty. It doesn't help that the remaining 95 bricks have more charge. Since they are in series, the weakest cell (or in this case brick) is the hard limit. That makes a single cell lost in one brick is the same as 96 cells failing, one in each brick.
Think about a simple two cells in series battery pack. One cell has 2000 mAh, the other 3000 mAh. Once the first cell is empty, it doesn't help that the second still has 1000 mAh left. Once the weakest cell is series is empty, the entire pack has to stop discharging.
That's what I suspect is happening with the packs that cause the car to shut down way before 0 miles on the display. The BMS doesn't know about the failed cell in one brick until this one brick reaches it's lowest voltage and then the car needs to protect it from a deep discharge and shuts the car down. I would think/hope that after a full cycle the BMS registers the lower capacity in the brick with the failed cell and adjust the total capacity accordingly. That would explain the unusually high 'degradation' on the pack.
Let's do the math on that. The car was reporting 209 miles of range and that is calculated at 295 Wh/mile. You were running at 360wH/mile which is ~22% more energy expended per mile. That would mean that you should have been able to drive approximately 163 miles. You only managed to drive 139 of those miles so you should have had about 24 left. (Which lines up with the 16 miles of range reported at the time of the shutdown.)
Could there have been anything else that triggered the shutdown? Like trying to accelerate or going up a hill? (Since those can cause a voltage drop that will cause a premature shutdown.)
With that kind of driving, I am not surprised that you only get 160 miles of range, starting at 209 miles t a full charge. Essentially his car is now an S60 after 300k miles and 7 years, which seems on par.
Now the fact that it stopped at 16 miles remaining, can be attributed to not reducing the speed and high acceleration at that point.
I think there is more to this story that we are not hearing... the Tesla side of the story. If they are refusing to fix the battery under warranty, then there has to be a good reason. So it is only wise not to jump to conclusions
gilscales
Banned
WHHHHAAAT?................WHHHHAAAT?.................WHHHHAAAT?..........OKAY!
Tam
Well-Known Member
Tesloop's battery degraded 6% but had an inaccurate gauge. The car died when the battery gauge indicated 10 miles. Tesla replaced the battery:
"Then, just as the car hit 200,000 miles, the range estimator became inaccurate. Though the car didn’t actually lose any range, the estimator would say it could go another ten miles—and then power down. Tesla looked into the issue, and told Tesloop that there’s a battery chemistry state that high-mileage cars go into, and the software isn’t properly compensating for that change. There will be a firmware update in three months that will take care of the discrepancy, but Tesla just replaced the battery to solve the problem. “We got our 6% range back with the new battery,” Sonnad said with a laugh. “But had the firmware been updated, we’d be fine and plugging along.”"
Tesla seems to take seriously about what the battery gauge says: Your car should not die when it the gauge shows above 0 miles.
That means, if your car dies when the battery gauge shows above 0 miles, Tesla would investigate the incident and make you whole.
@HMARTINPT, you could try talking to a different service center and see if they are more helpful. I recommend describing the issue in a simpler way. You have 209 miles rated range at 100% instead of 267 miles when new. That means you have 209/267= 78% capacity left. Your mileage is 239,000. The average S/X battery capacity at this mileage is 90%. Your degradation is more than twice the average.
The number of charge cycles causes a certain amount of degradation that can't be avoided. The more cycles the more degradation. That's normal. However, some batteries degrade more on top of that. The most important factor that would cause additional degradation is the amount of time the battery spends close to 0% and 100%. Let's say overnight you have set it to 100% because you have a trip tomorrow. The battery reached 100% at 3 am and you drove off at 9 am. That means the battery was subject to parasitic chemical reactions for 6 hours. Doing this regularly is a guaranteed way to ruin the battery. In comparison, Supercharging to 100% regularly is not an issue because you drive off after Supercharging.
Similarly, arriving at your destination with close to 0% and plugging-in to a 110V outlet would be bad because the battery would spend more time close to 0%. If you do this regularly, those hours would add up over time and it would ruin the battery. However, if you arrive with 0% and you plug-in to a NEMA 14-50 outlet, that's not an issue. The total number of hours the battery spends close to 100% or 0% in its lifetime is what determines the additional degradation.
If Tesla replaces this battery, you might want to consider selling this car and switching to another Tesla with more range so you can avoid getting close to 100% and 0% regularly if that's an issue. Check out the range table here.
The number of charge cycles causes a certain amount of degradation that can't be avoided. The more cycles the more degradation. That's normal. However, some batteries degrade more on top of that. The most important factor that would cause additional degradation is the amount of time the battery spends close to 0% and 100%. Let's say overnight you have set it to 100% because you have a trip tomorrow. The battery reached 100% at 3 am and you drove off at 9 am. That means the battery was subject to parasitic chemical reactions for 6 hours. Doing this regularly is a guaranteed way to ruin the battery. In comparison, Supercharging to 100% regularly is not an issue because you drive off after Supercharging.
Similarly, arriving at your destination with close to 0% and plugging-in to a 110V outlet would be bad because the battery would spend more time close to 0%. If you do this regularly, those hours would add up over time and it would ruin the battery. However, if you arrive with 0% and you plug-in to a NEMA 14-50 outlet, that's not an issue. The total number of hours the battery spends close to 100% or 0% in its lifetime is what determines the additional degradation.
If Tesla replaces this battery, you might want to consider selling this car and switching to another Tesla with more range so you can avoid getting close to 100% and 0% regularly if that's an issue. Check out the range table here.
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Yes we were driving on a highway that wasn’t complete flat the entire time. We never had the issue before with the car only getting 139 on this exact same trip nor having the car die with 16 miles left on the range indicator. I agree with the other post that Tesla wants the range indicator to be more accurate than that or there will be a lot more drivers dissatisfied.
I wish there was more to the story but there isn’t. Tesla has always been good to us in the past. We have had 3 power trains break and had to be towed each time. They replaced and did there best to make it right. The only explanation they can give is that they will not cover degradation. I am just trying to make sure people are aware of the situation and will keep everyone posted of any new information from Tesla.
OP, will you please clarify something for me. You indicated that the car charged to 309 miles. You also indicated that you charge to 85% to 90%. Was the 309 mile range shown on the car at an 85-90% charge, or did you charge to 100% to get a 209 mile range indication on the car.
I ask because I charge to 89% on my 2013 P85, which gives me a range of 227-229 miles indication on my car.
Also, the range indication is based upon an assumed speed of 55mph on 2012 and 2013 model S cars. The faster you drive the more energy you use and hence the shorter your range. Headwinds, rain, snow, cold temperatures also reduce the range of the battery. Your energy usage of 360 Wh/mi is very high.
I ask because I charge to 89% on my 2013 P85, which gives me a range of 227-229 miles indication on my car.
Also, the range indication is based upon an assumed speed of 55mph on 2012 and 2013 model S cars. The faster you drive the more energy you use and hence the shorter your range. Headwinds, rain, snow, cold temperatures also reduce the range of the battery. Your energy usage of 360 Wh/mi is very high.
That was my point. If you drive at 360 Wh/mile then a 209 initial range will give you around 164 miles. The rated range is at 295 wh/mile and so at 360 wh/mile that is 22% increase in consumption, which comes to a loss of 46 miles - all due to driving patterns and weather.
So the only question is why did the car stop with 16 miles remaining?
This is my theory: When you get below 10%, it is not uncommon for the car to shutdown if you continue to drive aggressively. The car in fact warns you to drive slow.
Is that your way of saying "Yes, we were still driving uphill at 75MPH when the remaining range was only 16 miles."? If so, that is the reason the car shutdown early.
This is a difference between ICE and BEV vehicles. For the most part an ICE maintains full performance "until the last, available, drop" while a BEV loses power output capability when it is at a low state of charge. And when low it is very vulnerable to a high demand/load causing the voltage to sag which will trigger a shutdown to protect the battery.
When I used to visit my son at college in State College, PA, the trip was 208 miles one way uphill. I would do a 100% charge (265 miles indicated range when new). But due to the speed of travel and it being uphill, I would arrive with only 2 miles range left. So I effectively “lost” 55 miles of range due to travel conditions. If it rained or was cold, I would have to slow down to reach my destination. In fact the car would tell me to slow down to xx mph in order to reach my destination. I wonder if the OP ignored such a warning or never got a warning.
I am curious to know whether his 209 rated mile range st charging is when charging to 100% or the 85-90% range ge says he charges at. If it’s at a 85-90% charge, then he does not really have an issue with sever degradation of the battery.
I am curious to know whether his 209 rated mile range st charging is when charging to 100% or the 85-90% range ge says he charges at. If it’s at a 85-90% charge, then he does not really have an issue with sever degradation of the battery.
henderrj
Active Member
Not to be rude but this smells a bit to me. The only posts this user has ever made are in this thread. I realize it's early but where are the technical details? (Like CAN bus.) Where are some pictures? Why the pretty family picture? (Okay, maybe you are just proud.) Could we still have shorts trying to manipulate the stock? Guess the number of manipulative posts in this anonymous setting leaves one a bit jaded.
There are a few puzzling issues with this story so far. First, there's the shut down at 16 miles indicated range. There are a bunch of reasons why that is possible, even if that is rare. Mainly, some sort of voltage sag (high current draw) right at the bottom of the pack's state of charge can make the car shut down to protect the battery pack. That surge of power usage can be the heater combined with some acceleration can cause the car to shut down. It is rare at 16 miles of rated range, but possible. It is more possible if the car's BMS is out of calibration or the pack is very much out of balance.
Talking about replacing the drive units doesn't affect or help the situation with the battery pack. The OP keeps talking about the power train, which I assume means the drive units. There's guidance for when to replace those. There's also guidance on replacing the battery pack. And there is no cell degradation warranty on the S/X, but that doesn't mean Tesla shouldn't cover this case if the issue is actual cell problems. But it also doesn't mean that Tesla should cover the issue if it is just cell degradation.
If the reduction in pack capacity is because some cells have a defect and are no longer part of the pack, then replacement is part of the warranty. It is also possible if a group of cells is in particular in bad shape. But if all the cells come back as having the same capacity, then it isn't a warranty issue. It's overall cell degradation given the OP's driving habits. Using an app that pulls the cell voltages can also help determine if there is a problem. Note, Tesla doesn't usually replace a pack with a new pack... it should be a pack with roughly the same degradation level with all the cell groups intact. So if the cells are all reading the same, then Tesla's replacement would be a pack with the same range.
Usually, if Tesla doesn't believe this is a problematic pack, they usually do recommend some balancing. The car only top balances, when the state of charge is over 93%. So the question is, has the OP done any balancing? Did Tesla indicate how the cells were doing as as balance? Usually, they recommend charging to 100%, waiting, then driving down to < 20 miles, and repeat twice on these older packs.
If it turns out that there is a particular cell module at fault, at this point, I thought it was possible for Tesla to replace individual modules. Is this a Rev A pack?
Talking about replacing the drive units doesn't affect or help the situation with the battery pack. The OP keeps talking about the power train, which I assume means the drive units. There's guidance for when to replace those. There's also guidance on replacing the battery pack. And there is no cell degradation warranty on the S/X, but that doesn't mean Tesla shouldn't cover this case if the issue is actual cell problems. But it also doesn't mean that Tesla should cover the issue if it is just cell degradation.
If the reduction in pack capacity is because some cells have a defect and are no longer part of the pack, then replacement is part of the warranty. It is also possible if a group of cells is in particular in bad shape. But if all the cells come back as having the same capacity, then it isn't a warranty issue. It's overall cell degradation given the OP's driving habits. Using an app that pulls the cell voltages can also help determine if there is a problem. Note, Tesla doesn't usually replace a pack with a new pack... it should be a pack with roughly the same degradation level with all the cell groups intact. So if the cells are all reading the same, then Tesla's replacement would be a pack with the same range.
Usually, if Tesla doesn't believe this is a problematic pack, they usually do recommend some balancing. The car only top balances, when the state of charge is over 93%. So the question is, has the OP done any balancing? Did Tesla indicate how the cells were doing as as balance? Usually, they recommend charging to 100%, waiting, then driving down to < 20 miles, and repeat twice on these older packs.
If it turns out that there is a particular cell module at fault, at this point, I thought it was possible for Tesla to replace individual modules. Is this a Rev A pack?
For someone who has driven over 250k miles, I thought they would know by this time the effect of speeding on the efficiency and hence the range, and also how to drive when you just have a few miles left.
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