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Tesla created secret team to suppress thousands of driving range complaints

reuters.com

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Re: Tesla created secret team to suppress thousands of driving range complaints

#91
post #79

Earlier quoted context omitted.

> Seems like it’s common across all EVs for the range to be inflated by around 20%, at least for freeway driving. Most people speed on the freeway. Extra speed reduces range significantly.

And much more than one would intuitively think. I just finished a long drive for summer vacation. Driving through Denmark (completely flat) at 130 km/h would absolutely wipe the battery, would be surprised if I managed even 350 km on a full charge. Driving over the mountains in Norway however, from 0m elevation to over 1000m and down again, at slower mountain roads (max 80 km/h), yielded almost 500 km on single charg…

Air resistance is proportional to square of velocity. That goes up pretty quickly!

Re: Tesla created secret team to suppress thousands of driving range complaints

#93

I have a model Y. I hate almost everything about it. But most germane, The "Battery meter" at the top of the display is total bunk. That's got to be "rosy" numbers. It'll display a the battery in miles, but it's at least 25% inflated. However if you punch in a destination, you'll get exact numbers, and those are insanely reliable. It claims (and I don't believe any claims coming from tesla) that it'll factor wind, el…

Battery meter at the top is EPA range - ie. the official range measurement method, in basically ideal conditions. The routefinder 'learns' from your previous driving habits. Driving style easily has a 50% impact on range between "drives 50 mph slipstreaming behind a truck" and "drives 90 mph and brakes aggressively at every corner".

No reason it has to show the EPA range. My family’s Subaru has “learned” that it lives in the mountains and the range estimates reflect that. And I’m pretty sure it’s a simply looking at what kind of gas mileage it got recently. When we have kayaks on top of the car, it readjusts the mileage estimates down pretty quickly.

All these comments about ICE vehicles being the same ignore that when ICE vehicles have estimates to empty, they take basic steps to try to get the estimate correct.

Re: Tesla created secret team to suppress thousands of driving range complaints

#94
post #75
post #49

Earlier quoted context omitted.

That only makes sense if there's strong correlation between the first 50% of a charge and the second 50% of a charge, but NOT an equally strong correlation between the previous charge cycle and the current charge cycle. That can be the case (eg on road trips) but usually isn't. Why not just always give the more precise estimates?

How does the car know what conditions its going to be driving in? I don't believe Elon has installed a time machine yet into a Tesla.

Er? Perhaps the car could make use of sensors that every ice and ev vehicle has had installed for decades, along with previous driving habits?

Re: Tesla created secret team to suppress thousands of driving range complaints

#95

Earlier quoted context omitted.

Battery meter at the top is EPA range - ie. the official range measurement method, in basically ideal conditions. The routefinder 'learns' from your previous driving habits. Driving style easily has a 50% impact on range between "drives 50 mph slipstreaming behind a truck" and "drives 90 mph and brakes aggressively at every corner".

I thought braking aggressively increases range.

No? Accelerating and decelerating are both lossy, and for the brief intervals when you're going faster you're also taking additional wind friction loss.

Most EVs (including Tesla) do have regenerative braking, so some of your energy is converted back into electricity when you brake, but nowhere close to all of it, so people who have a smoother, less aggressive profile will get more range.

Also if you brake really aggressively, you're dissipating more energy than can be successfully harvested and the rest is converted to heat, losing the energy you paid for and also increasing maintenance costs.

Re: Tesla created secret team to suppress thousands of driving range complaints

#96

Earlier quoted context omitted.

I thought braking aggressively increases range.

No? Accelerating and decelerating are both lossy, and for the brief intervals when you're going faster you're also taking additional wind friction loss. Most EVs (including Tesla) do have regenerative braking, so some of your energy is converted back into electricity when you brake, but nowhere close to all of it, so people who have a smoother, less aggressive profile will get more range. Also if you brake really agg…

I see, thanks for explaining!

Re: Tesla created secret team to suppress thousands of driving range complaints

#97
post #60

Earlier quoted context omitted.

You have it backwards. The car serves you. You should not have to serve the car (beyond universal, traditional things, like the need to maintain, insure, etc.). It’s reasonable to ask for a range estimate that’s not naively optimistic.

That’s never been the case. Drive down moderately steep grades and shift to a low gear to spare you breaks, for example. It’s the same argument. We don’t drive black boxes. Anecdote, a relative drove trucks in the Korean War and after, his vehicles lasted much longer per miles driven without maintenance due to how he drove.

Would you expect manufacturers to publish maintenance schedules assuming everyone drives like your relative, or based on maybe the 25th percentile of how people actually drive?

IMO product designers should not assume that the typical customer is a hyper-optimizer.

Re: Tesla created secret team to suppress thousands of driving range complaints

#98

Earlier quoted context omitted.

Battery meter at the top is EPA range - ie. the official range measurement method, in basically ideal conditions. The routefinder 'learns' from your previous driving habits. Driving style easily has a 50% impact on range between "drives 50 mph slipstreaming behind a truck" and "drives 90 mph and brakes aggressively at every corner".

I thought braking aggressively increases range.

Braking doesn't increase range. Rather the natural foot off pedal regen braking increases range. If you physically slam on brakes, I'm sure that doesn't help range.

Re: Tesla created secret team to suppress thousands of driving range complaints

#99
post #62
post #48

Earlier quoted context omitted.

As the article (or another poster) points out, you get a different algorithm when you look at the dash on a random day vs. when the Tesla knows you are going on a trip. That's even more damning to me. Edit: Also a different algorithm when below 50% charged. As some of the replies point out, a destination does supply more information. The current charge level does not.

How does the Tesla know I'm going on a trip? Are you implying its strange that the Tesla can calculate a more accurate range estimate when you literally tell it where you want to go to its computer which can use map data to calculate energy usage, versus you just driving around in circles in a arbitrary area and the computer only can assume based on EPA average usage?

It doesn’t use average usage to calculate the remaining range, it uses EPA numbers which are 200 Wh/mi or less. Which, interestingly, is less than the consumption shown on the Monroney sticker. How they can show two contradictory numbers on the same official document is fascinating to me.

Re: Tesla created secret team to suppress thousands of driving range complaints

#100

Earlier quoted context omitted.

I'd like to see more data... For example, if you get 10 tesla cars of the same model, do the ranges differ? If you get 1 car and 10 different drivers, do some drivers get the advertised range while others don't? If you disassemble the battery packs, do you find some bad/degraded cells in cars with reduced range, or is this a design fault? Do drivers that have trouble have inefficient mods, like roof racks, big wheels…

I don't think you need more data. Tesla had a team of people "managing" this issue to relieve demand on their service centres. What more data do you think would be useful to clarify Tesla's actions?

That statement alone sounds good to me... If there is no repair action that can fix the range issue on these cars, then it is a waste of everyone's time to go to a service center only to have a service tech poke the battery and realise it's fine. What are you expecting them to do when you arrive? They certainly won't be taking out battery cells and putting them under an electron microscope... And measuring battery voltages and currents is already done automatically by the computer.

There is very little you will diagnose on a modern car that the onboard computer isn't already aware of.

Therefore... the idea of a team of remote diagnosis people to fix most issues without a service appointment makes perfect sense.

As does the idea of having the analysis done automatically beforehand so the human doesn't have to wait.

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