More regen? I seem to be getting less...

[TEG]

So I got 42.2.1 firmware advertising more regen power:

But in practice, on my morning commute, I am now getting lots of regen power restricted "dots" on the regen meter, and it is giving me noticeably less regen than before.

( And it isn't even that cold. My outside temp was showing 54 degree this morning. )

 

[ezevphl]

This is exactly what I've seen. It feels a bit smoother but not as aggressive and less conducive to one pedal driving. Since temps were in the 40s and 30s I assumed that was partially to blame.

 

[mongo]

So I got 42.2.1 firmware advertising more regen power:

View attachment 353172

But in practice, on my morning commute, I am now getting lots of regen power restricted "dots" on the regen meter, and it is giving me noticeably less regen than before.

View attachment 353173

( And it isn't even that cold. My outside temp was showing 54 degree this morning. )

Regarding the display:
IF the dots represent the same unit of regen(power), then having a larger max regen would cause more dots to show up for the same absolute level.

Made up numbers: Can only use 50kW out of 60kW (2 dots) vs 50 out of 80 (6 dots).

 

[TEG]

With that many dots showing it felt like I barely had any regen. It was much less than I was used to before the update.

No more "one pedal driving", and I am pushing the friction brake pedal a lot more now.

 

[Glamisduner]

I wonder if they are being more conservative with the new battery chemistry with the additional silicon oxide likely found in 2170 batteries. The silicon oxide expands 100's of times more than graphite in traditional lithium batteries. Expansion over time degrades batteries more quickly. I'm not sure why this would be cold specific but I do wonder if it related in some way (maybe not even due to silicon oxide) to the new battery chemistry.

video on tesla battery chemistry:

 

[mongo]

I wonder if they are being more conservative with the new battery chemistry with the additional silicon oxide likely found in 2170 batteries. The silicon oxide expands 100's of times more than graphite in traditional lithium batteries. Expansion over time degrades batteries more quickly. I'm not sure why this would be cold specific but I do wonder if it related in some way (maybe not even due to silicon oxide) to the new battery chemistry.

video on tesla battery chemistry:

2170s are a different form factor, but likely the same chemical makeup at the 18650s. I doubt they would go back to silicon after the issues with the 90kWh packs (silicon infused 85 packs).

 

[Glamisduner]

2170s are a different form factor, but likely the same chemical makeup at the 18650s. I doubt they would go back to silicon after the issues with the 90kWh packs (silicon infused 85 packs).

So the video is incorrect?

 

[WileyTheMan]

Could be just me, but I haven't noticed an improvement in my regen, even when I have no dots.

 

[mongo]

So the video is incorrect?

I'll admit, I didn't watch the whole thing since it looked like a third party vide, was there Tesla sourced chem data?

 

[Glamisduner]

I'll admit, I didn't watch the whole thing since it looked like a third party vide, was there Tesla sourced chem data?

I dunno it's not my video but the first 4 minutes talk about tesla battery chemistry. They sound pretty convincing and way more information that most articles I read but who knows?

 

[David L]

My 3 is definitely providing more regen after the update, but I drive in sunny CA, where we think 50F is cold.

 

[mswlogo]

So I got 42.2.1 firmware advertising more regen power:

View attachment 353172

But in practice, on my morning commute, I am now getting lots of regen power restricted "dots" on the regen meter, and it is giving me noticeably less regen than before.

View attachment 353173

( And it isn't even that cold. My outside temp was showing 54 degree this morning. )

More or less dots has nothing todo with "more regenerative braking" in version 42.2.

It didn't say more or less regenerative braking with a COLD battery. It said more regenerative braking (meaning when it's fully warmed up).

Also CURRENT ambient temperature by morning has little to do with it. What was the over night temp? And how long was it low?

If you have that many dots, your battery is pretty COLD, pure an simple and takes a LOT of driving to warm it up. I have had dots showing for 50 miles of driving when it's 40F out. Am I freaking out, absolutely not, I fully expected it.

Your car probably won't see a NORMAL full day of operation until the temperatures STAY above 50F for 24 hours.

Let the battery manage itself.

All threads and complaints are just gonna drive Tesla to HIDE more stuff.

Your car is running fine.

At what I've seen with temps between 30-40F, I'm sure there will be WEEKS we don't see full regen when it gets down to single digits. And you won't be able to drive it into regen at all. I'm getting close to that already. Drove 50 miles at 32F and still had dots. And once the dots were gone the supercharger would not go over 50kW because it knows the battery is still to cold.

Between Winter tire changes, temps dropping, software changing and lots of new users; folks are pointing fingers at stuff you simply cannot conclude until you have conditions that CAN do full regen. Anything that exposes battery to below 50F over the past 24 hours could affect the system. It's a ton a mass to warm up. And just normal highway driving doesn't generate all that much heat. If it did, it would be normally to much waste and we've never see the ranges we have. The system is designed to not create unnecessary heat.

There is TONS of info about how EV's are less efficient when it gets cold. You did do you homework before slapping down $60-$80K didn't you?

One thing I sure wish Tesla would show is what is the coolant temp. That would help give a clearer picture of why the car behaves the way it does. I suspect we could probably calibrate the number of dots to the coolant temperature

 

[tread]

I've definitely noticed an increase in regeneration. On an optimal temperature day (70s), I used to struggle getting below 240 wh/mi, but now I'm easily getting under 220 in routes that I normally travel. The first day that the update arrived, I could without a doubt tell that regen was much more aggressive when letting go of the pedal.

I would have to agree that limited regen you are seeing is from the temperature changes. Like @mswlogo has stated, it has more so to do with the overnight temperature and what temperature the battery is actually at versus ambient. On days that it's 55 by 9am and I leave the house, the overnight temperature dipped to the 40's and I had limited regen on my battery, so I would take that into consideration.

A good trick to circumvent this is to charge 5 - 10% less than what you normally charge to during colder temperatures, and then raising the limit 30 - 45 minutes before you leave so that the battery charges up to your normal limit and warms up the battery for you. If you follow this strategy, you'll have no limited regen when you leave your driveway.

 

[ecarfan]

On one hand it's great that we can get frequent over the air updates but on the other hand it is frustrating that drive characteristics are contantly in flux. i.e. Regen changes.

I would not put it that way. Tesla is regularly making changes to the firmware, that is true. But the fundamental driving characteristics of the car don’t really change.

And I have not noticed decreased regen on V2018.42.4 (which I am currently on) or 42.2 compared to earlier versions.

 

[dusdev]

As been reported in multiple threads, several people (including myself) experienced significantly decreased regen after the 42.3 'upgrade'. On my AWD I pretty much lost all regen at highway speeds. When releasing the pedal the car simply coasted and didn't apply any negative force and hence no regen. Unfortunately this degradation in regen was muddied by people reporting reduced regen with winter tires around the same time. In my case, it was with the same tires - woke up with a firmware update and significantly less regen. I reported it to Tesla and they directed me to a SC. I haven't had an opportunity to book an appointment. And sadly I've also installed winter tires which is probably going to be identified as 'the issue' (again, the issue was there 2 weeks before the tires were changed).

 

[dusdev]

I would not put it that way. Tesla is regularly making changes to the firmware, that is true. But the fundamental driving characteristics of the car don’t really change.

Perhaps that's been your experience. My experience was completely the opposite. A firmware update significantly changed the driving characteristic. I used to be able to simply release the pedal at certain points in my daily commute and safely regen brake to stop signs. After the firmware update it is definitely not the case (with similar weather conditions).

 

[dusdev]

With that many dots showing it felt like I barely had any regen. It was much less than I was used to before the update.

No more "one pedal driving", and I am pushing the friction brake pedal a lot more now.

This happened to me going to 42.3 from 39.x. Basically regen was gone at highway speeds. I'm not happy it happened to you, but I'm glad that more people are noticing which will hopefully entice Tesla to investigate. I miss my one pedal driving also, it was one of my favorite features and it went away for me on 42.3

 

[zhu-]

A good trick to circumvent this is to charge 5 - 10% less than what you normally charge to during colder temperatures, and then raising the limit 30 - 45 minutes before you leave so that the battery charges up to your normal limit and warms up the battery for you. If you follow this strategy, you'll have no limited regen when you leave your driveway.

That's a clever trick and would be great if built as a feature inside the app. You can set what time you plan on getting into your car and it'll calculate when to start top-off charging to reach set limit while timing your entry with optimal system temperatures.

 

[TEG]

It didn't say more or less regenerative braking with a COLD battery. It said more regenerative braking (meaning when it's fully warmed up).

It doesn't qualify the statement with any mention of temps. It just said more regen, and I am getting less now.

Also CURRENT ambient temperature by morning has little to do with it. What was the over night temp? And how long was it low?

I was driving when it was 54 degrees out, but temps got as low as 40 degrees overnight while the car was parked in my driveway.
I am used to other EVs where regen typically isn't limited unless temps get below freezing.

If you have that many dots, your battery is pretty COLD, pure an simple and takes a LOT of driving to warm it up. I have had dots showing for 50 miles of driving when it's 40F out. Am I freaking out, absolutely not, I fully expected it.

I do expect some regen limitation at really cold temps, but this didn't seem cold enough to me to limit it so much.
Now in the afternoon with ambient temps at 60 degree, I am no longer seeing any dots and regen is back to normal/full again.
I didn't do much driving, the car just sat for the past couple hours before I headed off to lunch.

Your car probably won't see a NORMAL full day of operation until the temperatures STAY above 50F for 24 hours.

That does not appear to be the case. It is acting "normal" after just sitting in ~55-60 degrees for a few hours.

Your car is running fine.

I wish I had more regen in the mornings. I didn't expect it to be this limited.

 

[tread]

That's a clever trick and would be great if built as a feature inside the app. You can set what time you plan on getting into your car and it'll calculate when to start top-off charging to reach set limit while timing your entry with optimal system temperatures.

Agreed, tweeted elon.