2020.24.6.4 !

[BR666T]

I did some CHAdeMO testing today (put another way: I donated $13 to eVgo to bring you this juicy technical detail, lol). The behavior is unchanged since it was first discovered... thus to mean: very bad.

It heats the battery up to about 129 degrees F, which takes about 35%-70% SOC charge to get there (about half an hour or so?). Once it's there, it finally turns off the motor (battery heater) and the battery temp stays stable at about 126~F for the rest of the charge, while finally letting the battery get all the juice it's being fed.

It accounts for about a 10% charge rate (/cost) penalty, somewhere around $1.30 of a $13 charge session gone up in steam as the battery cooling system immediately works to cool the battery back down to 86F once it's stopped charging.

Thank you for this information. How does this behaviour differ from Supercharging?

 

[FalconFour]

Thank you for this information. How does this behaviour differ from Supercharging?

It doesn't differ, at all (that I've been able to see). The exact same behavior, tit for tat, applies to Supercharging -- which (entirely my opinion) is a major flaw since this doesn't apply to AC charging, only DC.

(to clarify: the fact that it heats is the flaw - hopefully Tesla doesn't get the idea that this should be "fixed" by super-heating the battery for AC charging too )

 

[TIppy]

In flat Florida I would agree with you. In the hills of Appalachia not so much. Here is a drive from this past weekend. Around 11 am there was a good length of regen going down a big hill, normally that follows going up a big hill . But there are blips elsewhere. Ignore the single lane farm equipment fun after 11:11. Everything before that was a 2 lane divided highway that had an occasional traffic light for cross traffic. I drove on autopilot over 95% of the time even for the lights.


View attachment 560851

In an earlier post I did qualify my statement as in "other than mountainous terrain." Also I should have been more precise in that I meant interstate highways which are limited to a maximum 4% grade in moderate terrain. Even here there are grandfathered exceptions which is why I said unlikely, not never. By the looks of your data, you were descending a pretty steep grade, maybe 6%.

 

[Atari2600]

Not sure what the grade was but I’ve been on FAR longer steeper grades on interstate traveling between Ohio and Florida that have emergency ramps for semi tractor trailers that lose control. In my ICE cars I would simply drive faster instead of braking. Have yet to drive it with a Tesla but would like to make a Florida trip whenever CV is no longer a threat for compromised people.

On my graph I also had one around 10:08 but my speed was not constant at that time due to initially following traffic in the right lane.

 

[smatthew]

Well, I have no links, but I believe it’s always more efficient to coast than using regen.
Certainly more efficient than staying in drive.
This car is fun to drive for so many reasons, finding ways to be more efficient is more fun than money saving.

If you want to save efficiency, and have fun , why wouldn’t you want to put it in neutral ?

Maybe you can do that in Canada. But in California that is illegal.
California Vehicle Code 21710 states, “The driver of a motor vehicle when traveling on downgrade upon any highway shall not coast with the gears of such a vehicle in neutral.”

Regardless of where you live, it's unsafe as you no longer have control of the car and have to shift before you can respond to anything.

 

[M109Rider]

Maybe you can do that in Canada. But in California that is illegal.
California Vehicle Code 21710 states, “The driver of a motor vehicle when traveling on downgrade upon any highway shall not coast with the gears of such a vehicle in neutral.”

Regardless of where you live, it's unsafe as you no longer have control of the car and have to shift before you can respond to anything.

That sucks for you guys.
Guess it’s a safety thing.

 

[XLR82XS]

That sucks for you guys.
Guess it’s a safety thing.

It's a CA thing.

 

[MarcG]

That sucks for you guys.
Guess it’s a safety thing.

Meh, I’ve been living in California and using neutral on gentle highway downhills for 20 years in various cars (two stick shift ICE, one DSG, and three EVs). Never resulted in an unsafe situation. How can that “rule” be enforced, anyway?

 

[iamnid]

Since placing the car in neutral amounts to just turning the regen off, I don't think you're gaining any efficiency vs. keeping your foot on the accelerator to maintain speed. I don't think it's constantly sending power to the motor if it doesn't need it to maintain the speed and I don't think you get any of the parasitic losses in speed/momentum usually associated with a transmission keeping it in park vs. neutral. Whatever floats your boat though - I don't think it's harmful, just unnecessary and not any more efficient than keeping it in drive.

 

[G78M3]

If you want to save efficiency, and have fun , why wouldn’t you want to put it in neutral ?

Because when in neutral, you cannot react fast enough if an emergency happens. Even worse, the car cannot react (think Emergency Braking, AutoSteer, etc). By coasting in Neutral you are forcing a very smart car to be dumb. Not to mention that really there are no efficiency gains.

 

[TIppy]

Not sure what the grade was but I’ve been on FAR longer steeper grades on interstate traveling between Ohio and Florida that have emergency ramps for semi tractor trailers that lose control. In my ICE cars I would simply drive faster instead of braking. Have yet to drive it with a Tesla but would like to make a Florida trip whenever CV is no longer a threat for compromised people.

On my graph I also had one around 10:08 but my speed was not constant at that time due to initially following traffic in the right lane.

In the mountains the grade on interstate is allowed to go to 6%. You would definitely need regen at that grade and 70 mph. You could increase your speed to about 110 mph to avoid regen. My comments were more about non mountainous areas where regen is usually not needed at interstate speeds. If the grade is accelerating you, then you are going to need regen which is, of course, better than brakes.

The length of the grade has no effect on regen, just the slope. It would be very unusual to see a grade over 6% on interstate, but they do exist.

This is all beside the point as the op of the neutral comment said he did this on "gentle downhills," so he would not need regen.

 

[GuyDude]

I did notice that smart summon works terribly with this update.

 

[Morhydro]

I've just been notified of this, looks like I might be the first Brit on here to see it but it is midnight here...

Will install it tomorrow.

I have a UK M3LR but have not seen this update yet. Looking forward as it is the first one that actually seems to offer new functionality.

 

[Matsayz]

Meh, I’ve been living in California and using neutral on gentle highway downhills for 20 years in various cars (two stick shift ICE, one DSG, and three EVs). Never resulted in an unsafe situation. How can that “rule” be enforced, anyway?

"They" would only know when your vehicle crashes and then the inspection of the scene but I imagine they'd only learn about the car being in neutral if there was a death. I get it in a manual but anything else is just not worth it *to me*.

 

[chrisf60526]

In flat Florida I would agree with you. In the hills of Appalachia not so much. Here is a drive from this past weekend. Around 11 am there was a good length of regen going down a big hill, normally that follows going up a big hill . But there are blips elsewhere. Ignore the single lane farm equipment fun after 11:11. Everything before that was a 2 lane divided highway that had an occasional traffic light for cross traffic. I drove on autopilot over 95% of the time even for the lights.


View attachment 560851

Nice. What app is that?

 

[Atari2600]

Nice. What app is that?

TeslaFi web interface.

 

[Matsayz]

TeslaFi web interface.

Give’em your referral code and you both get $5 off. It’s $50/yr btw

 

[Atari2600]

Give’em your referral code and you both get $5 off. It’s $50/yr btw

I forgot to list the cost. Feel free to give him your referral code. I'm too lazy to even figure out what it is.

 

[Matsayz]

Nice. What app is that?

here’s my referral code for $5 off

Sign Up

 

[qingshan]

It's a CA thing.

We've been called the Left Coasters but maybe it should be the No Coasters?