Arrived at charger with 0% and 1 mi, is this bad?

[Aerospace2061]

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[M0unt41nm4n]

It’s impressive. I would have been clawing my eyeballs out in anxiety.

 

[HaulingAss]

It's bad to let it sit around with a dead battery, but as long as you plug it in as soon as you arrive with 0%, you'll never know the difference.

0% is not really zero percent, there is a buffer below that.

 

[Stuck4ger]

 

[WormtownKris]

Coming home in our Model 3 a few months ago, I cut it "too close" and got to 0% battery and 0 miles about 3 miles from home (uphill as well). We were able to make it without bricking the car. So just like conventional ICE vehicles, it looks like Tesla built in a little cushion. It seems Running on Empty is a thing on Teslas as well. They don't publish/advertise this, and no idea how many miles grace we get, but you can go past 0, if you dare. YMMV, literally!

 

[countryboy]

Coming home in our Model 3 a few months ago, I cut it "too close" and got to 0% battery and 0 miles about 3 miles from home (uphill as well). We were able to make it without bricking the car. So just like conventional ICE vehicles, it looks like Tesla built in a little cushion. It seems Running on Empty is a thing on Teslas as well. They don't publish/advertise this, and no idea how many miles grace we get, but you can go past 0, if you dare. YMMV, literally!

Once after making a very bad route decision involving 100 miles of dirt road in podunk utah, had a predicted arrival of -2%... going 42mph on the interstate no A/C etc.. made it there with -1%. There's definitely a buffer, but that was 2018 M3 with early software, have heard many stories since of dying with 1% so I wouldn't rely on this.

 

[Stuck4ger]

It’s all about risk vs reward. I’ve seen enough cars arrive at superchargers on flat beds. I have no desire to impress anyone with that walk of shame — especially in a CT.

 

[HaulingAss]

It’s all about risk vs reward. I’ve seen enough cars arrive at superchargers on flat beds. I have no desire to impress anyone with that walk of shame — especially in a CT.

As a hang glider and a test pilot, I'm sure you have taken thousands of calculated risks. The fact that you're still here means either you are good at it, or lucky. I don't like to rely on luck too much when the consequences are serious, only acceptable risks should be taken. Some would say no additional risk is acceptable, I would disagree, it depends upon the consequences.

But just like you wouldn't personally take a risk that you have decided is unfavorable or not worth it, the secret is to understand what makes it a risk, and account for that the best you can. In the case of a Tesla, the biggest reason the vehicle could run out right at zero (or when it is still showing a mile or two remaining) is because the BMS had fallen out of calibration (the battery had lost track of its state of charge). That could happen when it had been a couple of weeks or more without running the battery down to a low state of charge so the BMS could have a look at how the battery behaves as it starts getting really low (and recalibrate itself to the new data).

In other words, know what you don't know. If my battery has been well-exercised very recently, I'm much more comfortable running it lower than if the state of charge has been yo-yo-ing between 50-70%. It also depends upon your time and location particulars. Sometimes, running out would be much more consequential than others. But I've not run out for over 40 years, since I was 19 years old and I forgot, I had already switched to reserve on my motorcycle tank. Fortunately, a friendly State Patrol happened by my somewhat remote location and put a gallon of gas in my tank, but not before he pointed a loaded handgun at my chest without the safety engaged and told me to put my hands in the air. But that's a story for another time.

In any case, the consequences of running out of juice before a pump or charger are laughingly inconsequential compared to not having enough glide slope in a hang glider to make it to a safe landing spot or finding out that the structural calculations in a prototype airplane or spacecraft didn't take into account all the necessary factors. I am not afraid of pulling off the road and walking away from my vehicle, because that is a contingency that I plan for (and it sure makes motoring on empty a lot less stressful).

Over the last three decades, I've had numerous free thrills, not only in my Model 3 Performance, but also purposefully riding my sport-touring motorcycle on fumes in remote areas, just to test my ability to know my motorcycle, understand a GPS, head or tailwinds, speed and efficiency, and knowing the potential unknowns and pitfalls (like whether the gas station will have gas and be able to deliver it). This was all for fun and games, but not once did I ever run out. I've filled my tank numerous times in which even a flashlight wouldn't show a teaspoon of liquid gas (the fuel injection filter holds about a cup). I wouldn't do it if it risked being late for a meeting or a family gathering. But I made it a point to know and understand the consequences of any risks I purposefully take. It was good, clean fun.

Life, without taking some risk, can be pretty dry. Some may even prefer that, and that's fine for them, don't put you hand in the cookie jar if you're not willing to get caught. I hope it's obvious that this is not a lecture, I just wanted to explain why the meme you posted, "Do you feel lucky, Punk?", actually reminded me of some fun, low consequence thrills I've had. And some where the risk was not so inconsequential.

 

[Kyril]

It's bad to let it sit around with a dead battery, but as long as you plug it in as soon as you arrive with 0%, you'll never know the difference.

0% is not really zero percent, there is a buffer below that.

How much of a buffer? Does anyone know for sure?

 

[Gaximus]

How much of a buffer? Does anyone know for sure?

Assume there is zero, then you won’t go wrong. Because even if you relied on 5% buffer, in cold weather, it’s gone.

 

[kpanda17]

It's bad to let it sit around with a dead battery, but as long as you plug it in as soon as you arrive with 0%, you'll never know the difference.

0% is not really zero percent, there is a buffer below that.

Using the buffer is a gamble, it’s failed me with ICEv
Batteries don’t like to be empty

 

[HaulingAss]

How much of a buffer? Does anyone know for sure?

The size of the buffer depends upon how well your BMS is able to calibrate itself at any given point in time. That variability is why Tesla put the buffer there to begin with, other manufacturers EV's have been known to die before zero is reached a lot more often than a Tesla. Things have to be real messed up for a Tesla to die before zero is reached.

Kyle from Out of Spec motoring has run EVs to dead more than anyone that I'm aware of and he assumes a Model 3 or a Model Y will have around 25-30 miles of 70 mph driving left when it reaches zero. Don't count on it, but that's what his experience has been. I think he's driven Cybertrucks to dead at least twice with similar results.

And this is a major reason why some people think EVs made by Tesla don't get the EPA range claimed (relative to other EVs), they tend to have a bigger buffer. The EPA tests assume the car is driven until it can no longer replicate the drive cycle it's on.

 

[mbeltran]

It’s fine, just takes longer to charge. Glad you made it.

 

[HaulingAss]

Using the buffer is a gamble, it’s failed me with ICEv
Batteries don’t like to be empty

I'm not recommending using the buffer, it's there so you can more reliably take it to zero. Tesla wants to avoid the situation where the car dies before the trip computer reaches "0 miles remaining".

 

[Stuck4ger]

As a hang glider and a test pilot, I'm sure you have taken thousands of calculated risks. The fact that you're still here means either you are good at it, or lucky. I don't like to rely on luck too much when the consequences are serious, only acceptable risks should be taken. Some would say no additional risk is acceptable, I would disagree, it depends upon the consequences.

But just like you wouldn't personally take a risk that you have decided is unfavorable or not worth it, the secret is to understand what makes it a risk, and account for that the best you can. In the case of a Tesla, the biggest reason the vehicle could run out right at zero (or when it is still showing a mile or two remaining) is because the BMS had fallen out of calibration (the battery had lost track of its state of charge). That could happen when it had been a couple of weeks or more without running the battery down to a low state of charge so the BMS could have a look at how the battery behaves as it starts getting really low (and recalibrate itself to the new data).

In other words, know what you don't know. If my battery has been well-exercised very recently, I'm much more comfortable running it lower than if the state of charge has been yo-yo-ing between 50-70%. It also depends upon your time and location particulars. Sometimes, running out would be much more consequential than others. But I've not run out for over 40 years, since I was 19 years old and I forgot, I had already switched to reserve on my motorcycle tank. Fortunately, a friendly State Patrol happened by my somewhat remote location and put a gallon of gas in my tank, but not before he pointed a loaded handgun at my chest without the safety engaged and told me to put my hands in the air. But that's a story for another time.

In any case, the consequences of running out of juice before a pump or charger are laughingly inconsequential compared to not having enough glide slope in a hang glider to make it to a safe landing spot or finding out that the structural calculations in a prototype airplane or spacecraft didn't take into account all the necessary factors. I am not afraid of pulling off the road and walking away from my vehicle, because that is a contingency that I plan for (and it sure makes motoring on empty a lot less stressful).

Over the last three decades, I've had numerous free thrills, not only in my Model 3 Performance, but also purposefully riding my sport-touring motorcycle on fumes in remote areas, just to test my ability to know my motorcycle, understand a GPS, head or tailwinds, speed and efficiency, and knowing the potential unknowns and pitfalls (like whether the gas station will have gas and be able to deliver it). This was all for fun and games, but not once did I ever run out. I've filled my tank numerous times in which even a flashlight wouldn't show a teaspoon of liquid gas (the fuel injection filter holds about a cup). I wouldn't do it if it risked being late for a meeting or a family gathering. But I made it a point to know and understand the consequences of any risks I purposefully take. It was good, clean fun.

Life, without taking some risk, can be pretty dry. Some may even prefer that, and that's fine for them, don't put you hand in the cookie jar if you're not willing to get caught. I hope it's obvious that his is not a lecture, I just wanted to explain why the meme you posted, "Do you feel lucky, Punk?", actually reminded me of some fun, low consequence thrills I've had. And some not so inconsequential ones.

I’ve coasted into gas stations twice, once to the dismay of my wife and amazement of my kids. But that was years ago. And I have landed an airplane with a dead engine and no fuel in the tanks (not my fault, I swear!). More recently I’ve regularly put more then 15 gallons of gas into my FJ’s 15 gallon tank. But it’s easier to jog and get a gallon of gas, than to get a Tesla to a charger. I guess if I lived closer to you I’d consider pushing my CT more

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