Will it though? Have you actually "stretched the legs" to see that the car won't deliver the actual range you expect?
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Tesla appointment for battery health concerns mysteriously disappeared
- Thread starter pete_shaw
- Start date
Will it though? Have you actually "stretched the legs" to see that the car won't deliver the actual range you expect?
super20g
Member
It would be nice if they would provide access to the battery health report so you see for yourself if there is real degradation or not... Even if there was a charge to run the test to generate the report I am sure that would put concerned consumers minds at ease a lot more than telling them to do this discharge/recharge dance that doesn't do anything (at least in my experience).
ucmndd
Well-Known Member
I get that Tesla's party line is "it's not real". But telling people to basically just keep driving even though the car says the battery is almost empty is just silly. Who's going to do that? I'm not going to take the risk of being stranded just because Tesla says the screen might be wrong. They need to be more transparent with their customers and fix the issue.
ucmndd
Well-Known Member
I’m not asking that anyone drive past zero or anything like that. I’m asking how people have confirmed that the displayed range is actually “15% less” compared to a new car as is being asserted.
I would. If I think I have 15% less capacity then I should, and Tesla says no it's not real...you better believe I am going to run that car down to prove it one way or the other. If I end up stranded on the highway then I was right and Tesla was wrong and they are coming to pick me and my car up for service, if not then I was wrong.
Edit: Granted...I would plan my route appropriately so that if the car does die it is not totally inconvenient for me.
I know. And I meant it more generally to Tesla's apparent stance rather than to you directly.
It's one thing to "test" it, as you are suggesting. I don't think that's an issue.
But it's something else for Tesla to suggest that it will get more accurate as you get to a lower SOC (I think that's what they're saying). They aren't being precise, but it seems to me like owners would have to have a lot of faith to just continue driving when their car says they have 25 miles left or something and just "hope" it's more accurate than it was at the higher SOC.
I don't know, maybe I'm making a silly point. It would be better if they just fixed the damn issue AND gave owners the ability to see their actual degradation like you can on an iPhone.
At this point I am more confused than ever. I see that discharging to 20% and then charging back to 100% was suggested and also 80% daily. If I am correct Musk suggested 10% then 100% and 90% daily. Can anyone clarify?
Also:
https://electrek.co/2019/10/04/tesla-software-updat-battery-capacity-loss-fire-investigation-nhtsa/
Also:
https://electrek.co/2019/10/04/tesla-software-updat-battery-capacity-loss-fire-investigation-nhtsa/
SilverSp33d3r
No Longer Silver
Switch to % remaining on display and forget the rest. Range displayed will vary but percentage will not. If your unhappy with actual range of your car then read up on how to maximize range. If that still doesn’t work go back to driving your previous car because electric is not for you.
This. The delivery centers should deliver all cars at 90% and verify that they are charging to the advertised range.
Otherwise Tesla should stop advertising range, only advertise capacity along with estimated Wh/mile. The thing is you can't buy an SUV with three different sized gas tanks. But people here don't have range anxiety, they have battery life anxiety. Perhaps a function of a technology that just hasn't had enough soak time yet.
Kitfox
Member
People think of EV range as an absolute. They think that if they get a 310-mile car, they will be able to start at 100% and drive 310 miles and be at 0% exactly. This is not an issue that people have with dino cars even though the same problem applies because gassers don't advertise their range.
Consider this...
You get a gasser with a 15 gallon fuel tank and 25 MPG. You never think about that as a 375 mile range. Nothing when you were buying the car was likely saying "375 mile range" with some exceptions, for example, a Prius Prime which advertises a 650 mile range). You -MIGHT- have something that says "340 miles to E" because most cars will be on "E" with about 1-2 gallons left in the tank. Actually driving with very little to no fuel in the tank is very bad for various parts of the car like the fuel pump. And even if you have "340 miles to E", you probably don't look at it unless you are in that "50 miles to E" range where the car puts it front and center. Some cars will even estimate based on the recent MPG, so 50 miles to E doesn't necessarily mean 2 gallons to E.
The way you drive and the environment of the drive and the road conditions and plenty of other factors go into how much energy it takes to go one mile. Rough roads mean more energy to move the car. Smooth roads take less. Uphill? Lots more energy and wow, 14 MPG. Down the mountain and you might get 40-50 MPG for that portion. That wind blowing at you takes more energy. A good tailwind takes less. Air conditioner? More energy. Windows down? Also more energy due to wind resistance. More people or cargo in the car? More energy. Driving faster? More energy. Even the amount of energy in a gallon of gasoline varies. 10% Ethanol = Less Energy. Warm fuel in the underground tank = Less Energy.
MOST drivers will end up driving and not getting anywhere close to the advertised MPG of the car. When they're close to Empty, they find a dino juice seller and put more dino juice in their car, never thinking "I only went 200 miles since I last got gas and this car should be able to get 375 miles."
The same energy efficiency factors into electric cars.
Take a Model 3 Long Range. It has an 75 kWh (kilowatt-hour, or 1000 Watt-hours) battery. Think of a "Kilowatt-hour" as a "pint of gas" so to speak. Not precisely, obviously, but yeah. It's worth just a bit under 4 miles "EPA rated" distance at about 240 Wh (Watt-hours) per mile. However the claimed efficiency is considered 29kWh per 100 miles, which is 290 Wh per mile, and that would be 259 miles.
Just like gassers, the Wh/m varies dramatically depending on many conditions. Same things. Rough road costs more energy. Uphill costs more energy. Open windows costs more energy. Driving faster costs more energy. Headwind costs more energy. Stop and go costs more energy. Downhill costs less energy. Smoother roads cost less energy. Driving habits can cost more or less either way. The energy app on the console will show energy consumption up to as much as 900 Wh/m but the consumption can be greater than that. It'll also show when the energy consumption is negative due to regeneration. During normal driving, you can see that line all over the place. You can see the average for the past 5, 15, or 30 miles. But you can't see the average beyond that.
How much does that Wh/m impact things?
240 Wh/m average will get you 312 miles on 75 kWh of charge.
250 Wh/m will only get you 300.
The efficiency rating (Not EPA rating. Efficiency takes into account climate control and other things) of 290 Wh/m will get you 259 miles on a full charge.
"But what about battery degradation? It's saying less range!"
It doesn't have a crystal ball. It can't see how you will drive, or where you will drive, or what the weather and temperature will be. It can measure Energy In and Energy Out and "How many volts is the battery?" Then it makes a GUESS based on these values as to the percentage of capacity left in the battery. THEN it makes a guess based on the EPA rating as to how many miles you can get.
The reality is that 99 out of 100 people will not get 310 miles on a LR. All the extra things (hills, road roughness, weather and temperature, speed) mean that really you should expect to get about 260 miles during good weather. But in optimal conditions and efficient driving, you can absolutely get 310 miles. Or even more. It just isn't the norm.
So Tesla really did a number on themselves by stating range. Especially since it's EPA-Rated range, which is similar to MPG ratings: Not gonna happen for most people.
Battery degradation though is determined by "The battery can no longer hold as much energy". So 10% degradation would be a 75 kWh pack only able to hold 67.5 kWh. But you can't tell this by the miles. The computer can only guess this by running the car from 100-10-100% to see how much energy the battery actually holds, and it can only guess the state of charge by the amount of voltage the batteries put out. 100% is 4.2v/cell under no load. The moment you add a load, even a tiny 1A load (about 350W) the voltage will drop to 3.9-4.0 0% is somewhere around 2.8-3.0 volts and also by how fast it drops through that. The drop from 3.4V to 3.2V takes three times as much energy as 3.2V to 3.0V, and six times as much energy as 3.0V to 2.8V.
The TL;DR version:
There is a massive electric dump truck at a mine that never has to be charged. Ever. It has a 600 kWh battery that it uses to take its 45 ton self uphill. Then it loads up with 65 tons of rock and uses regeneration on the way down. In an average day, it generates 200 kWh more energy coming downhill than it consumes going uphill.
Consider this...
You get a gasser with a 15 gallon fuel tank and 25 MPG. You never think about that as a 375 mile range. Nothing when you were buying the car was likely saying "375 mile range" with some exceptions, for example, a Prius Prime which advertises a 650 mile range). You -MIGHT- have something that says "340 miles to E" because most cars will be on "E" with about 1-2 gallons left in the tank. Actually driving with very little to no fuel in the tank is very bad for various parts of the car like the fuel pump. And even if you have "340 miles to E", you probably don't look at it unless you are in that "50 miles to E" range where the car puts it front and center. Some cars will even estimate based on the recent MPG, so 50 miles to E doesn't necessarily mean 2 gallons to E.
The way you drive and the environment of the drive and the road conditions and plenty of other factors go into how much energy it takes to go one mile. Rough roads mean more energy to move the car. Smooth roads take less. Uphill? Lots more energy and wow, 14 MPG. Down the mountain and you might get 40-50 MPG for that portion. That wind blowing at you takes more energy. A good tailwind takes less. Air conditioner? More energy. Windows down? Also more energy due to wind resistance. More people or cargo in the car? More energy. Driving faster? More energy. Even the amount of energy in a gallon of gasoline varies. 10% Ethanol = Less Energy. Warm fuel in the underground tank = Less Energy.
MOST drivers will end up driving and not getting anywhere close to the advertised MPG of the car. When they're close to Empty, they find a dino juice seller and put more dino juice in their car, never thinking "I only went 200 miles since I last got gas and this car should be able to get 375 miles."
The same energy efficiency factors into electric cars.
Take a Model 3 Long Range. It has an 75 kWh (kilowatt-hour, or 1000 Watt-hours) battery. Think of a "Kilowatt-hour" as a "pint of gas" so to speak. Not precisely, obviously, but yeah. It's worth just a bit under 4 miles "EPA rated" distance at about 240 Wh (Watt-hours) per mile. However the claimed efficiency is considered 29kWh per 100 miles, which is 290 Wh per mile, and that would be 259 miles.
Just like gassers, the Wh/m varies dramatically depending on many conditions. Same things. Rough road costs more energy. Uphill costs more energy. Open windows costs more energy. Driving faster costs more energy. Headwind costs more energy. Stop and go costs more energy. Downhill costs less energy. Smoother roads cost less energy. Driving habits can cost more or less either way. The energy app on the console will show energy consumption up to as much as 900 Wh/m but the consumption can be greater than that. It'll also show when the energy consumption is negative due to regeneration. During normal driving, you can see that line all over the place. You can see the average for the past 5, 15, or 30 miles. But you can't see the average beyond that.
How much does that Wh/m impact things?
240 Wh/m average will get you 312 miles on 75 kWh of charge.
250 Wh/m will only get you 300.
The efficiency rating (Not EPA rating. Efficiency takes into account climate control and other things) of 290 Wh/m will get you 259 miles on a full charge.
"But what about battery degradation? It's saying less range!"
It doesn't have a crystal ball. It can't see how you will drive, or where you will drive, or what the weather and temperature will be. It can measure Energy In and Energy Out and "How many volts is the battery?" Then it makes a GUESS based on these values as to the percentage of capacity left in the battery. THEN it makes a guess based on the EPA rating as to how many miles you can get.
The reality is that 99 out of 100 people will not get 310 miles on a LR. All the extra things (hills, road roughness, weather and temperature, speed) mean that really you should expect to get about 260 miles during good weather. But in optimal conditions and efficient driving, you can absolutely get 310 miles. Or even more. It just isn't the norm.
So Tesla really did a number on themselves by stating range. Especially since it's EPA-Rated range, which is similar to MPG ratings: Not gonna happen for most people.
Battery degradation though is determined by "The battery can no longer hold as much energy". So 10% degradation would be a 75 kWh pack only able to hold 67.5 kWh. But you can't tell this by the miles. The computer can only guess this by running the car from 100-10-100% to see how much energy the battery actually holds, and it can only guess the state of charge by the amount of voltage the batteries put out. 100% is 4.2v/cell under no load. The moment you add a load, even a tiny 1A load (about 350W) the voltage will drop to 3.9-4.0 0% is somewhere around 2.8-3.0 volts and also by how fast it drops through that. The drop from 3.4V to 3.2V takes three times as much energy as 3.2V to 3.0V, and six times as much energy as 3.0V to 2.8V.
The TL;DR version:
- You probably never thought of "Miles of range" in a gasser. Don't do so now.
- Battery capacity is not an exact science and the car is logically incapable of getting it perfectly accurate.
- Many, many variables go into how much energy it takes to go a mile, so you probably won't get that "rated" range anyway.
- There are no customer-facing tools in the car to determine battery health/capacity.
- If you think your battery is degraded substantially in under 80,000 miles, it probably hasn't. It's just the lack of a crystal ball for the computer.
There is a massive electric dump truck at a mine that never has to be charged. Ever. It has a 600 kWh battery that it uses to take its 45 ton self uphill. Then it loads up with 65 tons of rock and uses regeneration on the way down. In an average day, it generates 200 kWh more energy coming downhill than it consumes going uphill.
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