Battery died with 10 km Typical Range left?

[AnxietyRanger]

Seems you did not read the comment you were responding to. 180kmh it's no problem for the Tesla.
The issue here is that on very low SOC, the voltage is lower so for a given power, you need more current. At 6%, the amount of power is limited. So if you go very fast, and uphill, it can be too much power draw.
I am sure you haha experience an ICE car starting to rattle or shutdown when there was one 0.5l remaining in the tank and going uphill because the fuel is pumped on a location of the tank where there was no enough fuel? But it would not mean that the car could not run in normal conditions with more fuel, right?

I read the comment and stand by my opinion.

Many ICEs refuse to give low-end estimates at all, because they are not reliable - or inflate the low-end estimates to a safe degree. Tesla could do the same.

Showing 6% of range and then shutting down is not a very preferable scenario by any means. But then, as said, Teslas are not very good autobahn cars, so I am not really surprised it did this.

But also: I don't think this problem necessarily is a problem with Tesla's estimate algorithm, but an unrelated issue that causes a similar outcome, that could use better warnings. E.g. 12V battery issues.

 

[SuisseDriver]

Showing 6% of range and then shutting down is not a very preferable scenario by any means. But then, as said, Teslas are not very good autobahn cars, so I am not really surprised it did this.

And I stand by the fact that driving at 180km/h uphill is probably a little bit extreme when you haha 6% or 0.5 liter diesel in your tank.
But yeah, Tesla area bad cars for motorways, sure.

 

[AnxietyRanger]

And I stand by the fact that driving at 180km/h uphill is probably a little bit extreme when you haha 6% or 0.5 liter diesel in your tank.
But yeah, Tesla area bad cars for motorways, sure.

Where do you get the idea that 6% battery and 0.5 liter of diesel would somehow be comparable? A usual diesel tank is somewhere around 60-80 liters. We are talking 3-5 liters of diesel in the tank at 6%. 10 times more than your example!

Tesla failing at 6% range, due to lack of battery power, would be the same as an ICE stopping with several liters of gasoline in the tank, due to lack of gasoline - assuming that 6% is an accurate representation of course...

 

[ohmman]

Where do you get the idea that 6% battery and 0.5 liter of diesel would somehow be comparable? A usual diesel tank is somewhere around 60-80 liters. We are talking 3-5 liters of diesel in the tank at 6%. 10 times more than your example!

Tesla failing at 6% range, due to lack of battery power, would be the same as an ICE stopping with several liters of gasoline in the tank, due to lack of gasoline - assuming that 6% is an accurate representation of course...

It’s more like an ICE failing when the fuel gauge represented something like 6% remaining.

 

[AnxietyRanger]

It’s more like an ICE failing when the fuel gauge represented something like 6% remaining.

That's the whole point, though, isn't it?

If Tesla's "fuel gauge" says 6%, that is not an insignificant amount of power indicated. Equal to several liters of gasoline. On a P100D, that's "6" kWh...

If you can make that run out simply by pressing the accelerator to 180 kWh in one short period of acceleration, then the estimate isn't very good, is it?

 

[ohmman]

That's the whole point, though, isn't it?

If Tesla's "fuel gauge" says 6%, that is not an insignificant amount of power indicated. Equal to several liters of gasoline. On a P100D, that's "6" kWh...

If you can make that run out simply by pressing the accelerator to 180 kWh in one short period of acceleration, then the estimate isn't very good, is it?

That’s not what you said. I was aiding you in the analogy. You’re welcome.

 

[AnxietyRanger]

That’s not what you said. I was aiding you in the analogy. You’re welcome.

I wasn't trying to defend any inaccuracy on my part either, just move the point along?

Or is your aim to point out a mistake on my part?

 

[ohmman]

I wasn't trying to defend any inaccuracy on my part either, just move the point along?

Or is your aim to point out a mistake on my part?

I was trying to help with accuracy.

 

[AnxietyRanger]

I was trying to help with accuracy.

Quite fair, however I don't see how your second post helped with that. The first one, sure. The second, that seems to be something else.

 

[ohmman]

Quite fair, however I don't see how your second post helped with that. The first one, sure. The second, that seems to be something else.

Sorry if it was unclear. You seemed to dislike my clarification. I was (am) also on mobile on a ladder pruning a lemon tree. A reasonable time to be on TMC? Surely not. Do I have a problem? Maybe.

 

[AnxietyRanger]

Sorry if it was unclear. You seemed to dislike my clarification. I was (am) also on mobile on a ladder pruning a lemon tree. A reasonable time to be on TMC? Surely not. Do I have a problem? Maybe.

I didn't dislike your clarification in #64, it was fine. I get it that @SuisseDriver's comparison was apples and oranges to begin with - 6% on the screen vs. 0.5 liters in the tank. So, my comment certainly reflected that. Mostly I just wanted to keep on the point, though. I'm trying to prune unnecessary theoretical or "meta" debate branches... less arguing about arguing, so to speak... One lives in hope.

If your car shows 6% of "fuel", that's still quite a lot, and it shouldn't just run out at that level. What it most definitely isn't comparable to is 0.5 liters of diesel (as mentioned by @SuisseDriver), which is a very small amount, more like 0.6% than 6%.

If my Tesla shows 6% of range, I definitely don't expect it to shut down after one spirited acceleration.

 

[SuisseDriver]

If your car shows 6% of "fuel", that's still quite a lot, and it shouldn't just run out at that level. What it most definitely isn't comparable to is 0.5 liters of diesel (as mentioned by @SuisseDriver), which is a very small amount, more like 0.6% than 6%.

If my Tesla shows 6% of range, I definitely don't expect it to shut down after one spirited acceleration.

A"lot" is quite a stretch. I don't think you would consider that you have a "lot" of battery left if your handy would only have 6% remaining, do you?
Also, 6% of a 85D is around 4.7kW. That is less then the energy that you have in 0.5 liter of diesel (11*0.5=5.5kW). I was being generous.

Should it stop at 6%, probably not, for sure. But driving at 180 km/h uphill, when you know that the issue at low SOC is low voltage-higher current with so little energy left is also probably unwise.

 

[AnxietyRanger]

A"lot" is quite a stretch. I don't think you would consider that you have a "lot" of battery left if your handy would only have 6% remaining, do you?

I wouldn't expect a phone to suddenly shut down at 6%, absolutely not, no matter what I did with it. But arguably with a car this is even more crucial. The "6%" is the range indicator in a Tesla and if at that stage the battery can no longer offer reliable range, the range indicator definitely should not show 6%. Maybe it should have a range indicator saying 0.

Also, 6% of a 85D is around 4.7kW.

4.7 kWh is 15-20% of most other BEVs' batteries. It is not a small amount. The suggestion here on this thread was that nobody should drive a Tesla at under 10%. That's 10 kWh in my car. That's 30-50% of some other BEV's batteries. The suggestion is ludicrous. This is what prompted me to explore the question...

Should it stop at 6%, probably not, for sure.

Obviously it should not. The display, the warnings and the driving algorithms should be calibrated differently, if this indeed is an issue (and not a one-time malfunction of the car). If 180 kph is going to drain the battery super fast, it should still show linearity and appropriate warnings, not just shut down. If at 6% the car can't no longer offer reliable range, it should not display 6% but 0 instead - or separate battery percentage from range information (now they are one and the same in a Tesla).

when you know that the issue at low SOC is low voltage-higher current with so little energy left is also probably unwise.

I don't know that, let alone the average driver of an EV. If I need to take that into account, please calibrate the displays to reflect. I can be expected to monitor how range behaves in different climate and at different speeds, but going from 6% to 0% in one second is not reasonable.

I still think the car in question malfunctioned. It happens, nothing exceptional about that. However the suggestion that the last 10 kWh of a Tesla battery should never be driven on is either silly talk or Tesla seriously needs to recalibrate their range indicators.

 

[SuisseDriver]

I still think the car in question malfunctioned. It happens, nothing exceptional about that. However the suggestion that the last 10 kWh of a Tesla battery should never be driven on is either silly talk or Tesla seriously needs to recalibrate their range indicators.

I don't think I ever said otherwise. Indeed, driving a 75D, I definitely expect to be able to tap into those last 10% range to avoid stopping too much.
But I do not see myself trying to go 180km/h, up hill, when I will have 6% remaining, even if I know that the Supercharger is close.

Anyway, yes, I do not understand why it stops and it should just limit the power available (which I thought it is what it does) but until there are examples of car driven "normally" stopping at 6% (it may happen to me, let's hope not), I still think that this described case is very niche and not representative of what someone would normally do when reaching the bottom of the battery capacity.

 

[fsch]

So yesterday, for the first time in 5.5 years and 253 000 km, I got caught. I was 1 km from destination with +3 km of range left when the car decided that was it... And I lost 21 km of maximum range in the process.

After being alerted to safely pull over and stop the car, I was able to drive another 700 m of downward slope on neutral (accelerator not responding) before stopping ~100 feet from the top of an upward hill where I had to stop, 1000 feet from destination (family cottage). This is the 3rd time I went below 10 km of range in the life of the car, the other being 2 km and 1 km before safely reaching a supercharger, a few years back.

I asked Tesla Service if they could "unlock" these 3 km of range to achieve the last 200 m, but no luck. We tried to plug different combinations of extension cords to a neighbour (~200 feet), but no luck either, the mobile charger light was red (ground problem or low voltage?) So we finally called the AAA to achieve these last 1000 feet.

One bug, it seems, is that despite the main screen and computer were running (hence the 12 V battery), I was not able to push the button in the safety panel to release the parking brakes, despite pressing on the brake pedal as indicated. So no possibility to push the car to destination, and no possibility to release the brakes to pull the car on the flat bed. Fortunately, the road was slippery and the AAA guy had tire "skates", so he was able to drag it.

Another peculiarity of this adventure is that, through the process, until the car was loaded on the truck, the range remained at +3 km. But when I went back into the car after unloading it from the truck 10 min later, the systems were off and restated when I pushed the brake pedal. And at that point, the available range indicated 0 km. And then it took half an hour of charging at 45 km/h (240 V 50 A) before the car gains its first km of range. I should have got ~22 km by that time. So I fully charged the car to see, and indeed, my maximum range is now 362 km instead of 383 km a few days ago.

So it looks like Tesla cannot give you your last couple of km of indicated range, but they can increase the lower discharge limit of your battery by 21 km at once. And it looks like the range indicator is not as reliable as it was when the car was "only" 150 000 km old.

Multi-hundred-thousand-km Tesla owners, beware!

 

[croman]

Tow mode is what you needed to unlock the brakes. You had 12v is in the menu.

 

[Big Toys]

Ok, here's the bottom line:

You ride on fumes, you will occasionally lose, and do more damage to the battery than the thrill it provides. That's about all there is to it.

 

[murphyS90D]

The remaining range is a mathematical calculation as to what the computer thinks is left in the battery. There is no known way to actually measure it. The computer measures what is put in and what is taken out. Very cold weather reduces the usable capacity of the battery.

 

[fsch]

Ok, here's the bottom line:
You ride on fumes, you will occasionally lose, and do more damage to the battery than the thrill it provides. That's about all there is to it.

In all three instances of going below 10-20 km of range, it was the circumstances rather than the "trill" of "rid[ing] on fumes" that made me arrive tight. This time around, it was snow on the road and headwinds in the last part of the trip, unaccounted for in my planning. And trusting my prior experience that the car would keep going down to 2 km.

It helps knowing all the facts before affirming conclusions.

 

[Big Toys]

In all three instances of going below 10-20 km of range, it was the circumstances rather than "trill" of "rid[ing] on fumes" that made me arrive tight. This time around, it was snow on the road and headwinds in the last part of the trip, unaccounted for in my planning. And trusting my prior experience that the car would keep going down to 2 km.

It helps knowing all the facts before affirming conclusions.

You assumed that I am speaking to you, specifically, when the OP states that he habitually runs it to 1 km. All of us have run on gas fumes, either deliberately or accidentally, all of us have misjudged that gas gauge, and there is a certain "thrill" to have cheated the tow truck in either case when arriving to the gas station/house successfully. Who hasn't run that gauge deep into the red, just to see how many miles it represents for future reference? I know I have, noting how many miles I went. In the OP's case, his OCD requires that thrill of riding on the edge, but will have to calibrate his "gauge" differently, and with risk to the battery. I've had my MS battery down to 3 miles, twice, not on purpose. I don't really like to test that edge with compounding performance and environmental factors that may change the outcome.