Battery Management System - What I Learned At Tesla Service Center

[mrgoogle]

I'm going to avoid sharing any more of this doc, but there are a ton of goodies in it if you guys want to keep digging. just google "site: pastebin.com model3"

It looks like it is what is given to the service center, but really not sure. Got tipped off to it from a twitter post by green and was fairly easy to come across in google.

Can’t find it with google. Can any1 link it for me?

 

[Kevy Baby]

Can’t find it with google. Can any1 link it for me?

I'm just amused that someone with the handle "Mr Google" is asking for help in looking something up via Google

 

[Gasaraki]

I wonder what would happen if in an ICE car they had a display of gallons of fuel remaining with 0.1 gal precision and range remaining based on the EPA rated MPG multiplied by that number... would people would obsess over it? Take it in for service when, after filling up at the pump, the range-to-go was 5 mi less than window-sticker or when they drive a 23 mile commute to work and the range to go dropped by 26 miles?

Tesla could have just displayed the battery icon, no % number next to it, and no option to display range remaining. Or even more extreme, just made an E....1/2.....F bar. This would be the equivalent of an ICE gas gauge. Would everyone be happier?

I've never looked at the "miles" next to the battery. I always kept it at the percent left of battery. That's exactly how ICE cars does it, how much is left in your tank. I rarely used the ICE guesstimate on amount of miles left either, that thing is inaccurate as hell.

 

[N54TT]

I've never looked at the "miles" next to the battery. I always kept it at the percent left of battery. That's exactly how ICE cars does it, how much is left in your tank. I rarely used the ICE guesstimate on amount of miles left either, that thing is inaccurate as hell.

my only problem with that is in an ICE...full tank when new and full tank 10yrs down the road will pretty much drive about same distance. With EV....100% brand new and 100% even 5yrs later will NOT drive the same distance....especially at the rate the model 3 batteries seem to be degrading. Sure some will argue that ICE become less efficient as they age...but IMO it’s nothing significant enough to notice a decrease in range. A gas tank will always hold the same capacity of gas. A lithium battery will not always hold the same capacity of charge. Degradation will have a bigger impact on net range than any decrease in efficiency of an ICE.

Will it affect most daily driving? Probably not. But After 22 months my 100% is down from 310 to 272. I took a day trip the other day to Montauk. Left with 100% and got back with 15%. Brand new I’ve done that trip charging to 90%. Anymore degradation might start to require a supercharger stop to get back home. I know you can look at predicted range in the consumption screen....but you get a better routine indication of decreased range and on how much you need to charge when it’s set to miles rather than percent.

 

[TimothyHW3]

100% brand new and 100% even 5yrs later will NOT drive the same distance....especially at the rate the model 3 batteries seem to be degrading.

You have some good points, but that part - "rate the model 3 batteries seem to be degrading " is misleading.

Most reports you read of "fast degradation" are not really real degradation, but a misscalculation of the BMS. The BMS on Model 3 works differently than old Model S and X due to chemistry and pack density and connection of the cells. So the way you charge it is very important in order to have a good and balanced BMS. It has nothing to do with real degradation of the cells and the chemistry.

This information get's lost in the noise here on the forums, but charging the car only small increments leads to messed up BMS hence "degradation". We have thousands upon thousands of reports on this.
Mostly this is due to having the car "always plugged in" and driving short trips each day and charging back - like "the manual suggests".

I had a guy who apperently went with almost 0% degradation, but he was just charging 40%-60%. Once he charge 10 - 90 to 100% a couple of times he saw the real state of the car and the range dropped.

Having said that, the real degradation on the Model 3 is pretty small. I am at 20,000 miles and 1 year and have about 3% real, measured degradation. I charge very frequently almost top to almost bottom, so the car probably has a good idea of what is top to bottom and what the capacity is. I have also driven the top to almost bottom to confirm the numbers as in this video below.

So whatever you read about big degradation - don't. You can expect maximum of about 12-13% at 200,000 miles, 10% at about 150,000 miles and about 4-5% at 50,000 miles. That is common among most cars I see, give or take 1%.

Also, regarding the % vs miles thing on display.

We always hear from folks - I keep my car at % and never bother. Sure, if you have LR and only drive 100 miles a day and have a charger in your garage, I wouldn't care either.
But that applies to you and certainly doesn't apply to me - driving 200 miles at above US highway speeds, I need to know my range.

Try taking the car outside of the Supercharger network, with less chargers and try to squeeze out 250-280 miles from it on a single run, then you will begin to care. But then you will be mostly screwed, because you wouldn't know if the BMS is inbalanced, what the capacity of the car is and wether you can actually acchieve that.

You will also not know, what I show in the video below - mainly how to calculate the range based on the consumption and how tesla hides about 5% below 0. So by the time you see the % dropping fast, it will be too late.

So to summarize - driving EVs is, at least for now, still something that is not equal to all parties involved - due to different needs and the lack of great infrastructure (it is good, but still not great)
Overgeneralizing and giving advices based on your experience, i.e. "drive in % and forget about it", is actually a bad and dangerous advice to people who have no experience with the car.

 

[N54TT]

You have some good points, but that part - "rate the model 3 batteries seem to be degrading " is misleading.

Most reports you read of "fast degradation" are not really real degradation, but a misscalculation of the BMS. The BMS on Model 3 works differently than old Model S and X due to chemistry and pack density and connection of the cells. So the way you charge it is very important in order to have a good and balanced BMS. It has nothing to do with real degradation of the cells and the chemistry.

This information get's lost in the noise here on the forums, but charging the car only small increments leads to messed up BMS hence "degradation". We have thousands upon thousands of reports on this.
Mostly this is due to having the car "always plugged in" and driving short trips each day and charging back - like "the manual suggests".

I had a guy who apperently went with almost 0% degradation, but he was just charging 40%-60%. Once he charge 10 - 90 to 100% a couple of times he saw the real state of the car and the range dropped.

Having said that, the real degradation on the Model 3 is pretty small. I am at 20,000 miles and 1 year and have about 3% real, measured degradation. I charge very frequently almost top to almost bottom, so the car probably has a good idea of what is top to bottom and what the capacity is. I have also driven the top to almost bottom to confirm the numbers as in this video below.

So whatever you read about big degradation - don't. You can expect maximum of about 12-13% at 200,000 miles, 10% at about 150,000 miles and about 4-5% at 50,000 miles. That is common among most cars I see, give or take 1%.

Also, regarding the % vs miles thing on display.

We always hear from folks - I keep my car at % and never bother. Sure, if you have LR and only drive 100 miles a day and have a charger in your garage, I wouldn't care either.
But that applies to you and certainly doesn't apply to me - driving 200 miles at above US highway speeds, I need to know my range.

Try taking the car outside of the Supercharger network, with less chargers and try to squeeze out 250-280 miles from it on a single run, then you will begin to care. But then you will be mostly screwed, because you wouldn't know if the BMS is inbalanced, what the capacity of the car is and wether you can actually acchieve that.

You will also not know, what I show in the video below - mainly how to calculate the range based on the consumption and how tesla hides about 5% below 0. So by the time you see the % dropping fast, it will be too late.

So to summarize - driving EVs is, at least for now, still something that is not equal to all parties involved - due to different needs and the lack of great infrastructure (it is good, but still not great)
Overgeneralizing and giving advices based on your experience, i.e. "drive in % and forget about it", is actually a bad and dangerous advice to people who have no experience with the car.

I’ve read your posts throughout the board before. I’m well aware of the balanced BMS vs actual degradation debate. I’ve done the suggested methods to try and balance my BMS. It hasn’t really budged what SMT reports, which is 15% after 24k miles. There are plenty of posts and people I’ve spoken to with the same decrease in displayed range. I’m not trying to mislead people. In the end...for all intensive purposes....be it unbalanced BMS or real degradation....end user experience is a daily decrease in actual range. In hindsight I could have worded it differently.

 

[navguy12]

You have some good points, but that part - "rate the model 3 batteries seem to be degrading " is misleading.

Most reports you read of "fast degradation" are not really real degradation, but a misscalculation of the BMS. The BMS on Model 3 works differently than old Model S and X due to chemistry and pack density and connection of the cells. So the way you charge it is very important in order to have a good and balanced BMS. It has nothing to do with real degradation of the cells and the chemistry.

This information get's lost in the noise here on the forums, but charging the car only small increments leads to messed up BMS hence "degradation". We have thousands upon thousands of reports on this.
Mostly this is due to having the car "always plugged in" and driving short trips each day and charging back - like "the manual suggests".

I had a guy who apperently went with almost 0% degradation, but he was just charging 40%-60%. Once he charge 10 - 90 to 100% a couple of times he saw the real state of the car and the range dropped.

Having said that, the real degradation on the Model 3 is pretty small. I am at 20,000 miles and 1 year and have about 3% real, measured degradation. I charge very frequently almost top to almost bottom, so the car probably has a good idea of what is top to bottom and what the capacity is. I have also driven the top to almost bottom to confirm the numbers as in this video below.

So whatever you read about big degradation - don't. You can expect maximum of about 12-13% at 200,000 miles, 10% at about 150,000 miles and about 4-5% at 50,000 miles. That is common among most cars I see, give or take 1%.

Also, regarding the % vs miles thing on display.

We always hear from folks - I keep my car at % and never bother. Sure, if you have LR and only drive 100 miles a day and have a charger in your garage, I wouldn't care either.
But that applies to you and certainly doesn't apply to me - driving 200 miles at above US highway speeds, I need to know my range.

Try taking the car outside of the Supercharger network, with less chargers and try to squeeze out 250-280 miles from it on a single run, then you will begin to care. But then you will be mostly screwed, because you wouldn't know if the BMS is inbalanced, what the capacity of the car is and wether you can actually acchieve that.

You will also not know, what I show in the video below - mainly how to calculate the range based on the consumption and how tesla hides about 5% below 0. So by the time you see the % dropping fast, it will be too late.

So to summarize - driving EVs is, at least for now, still something that is not equal to all parties involved - due to different needs and the lack of great infrastructure (it is good, but still not great)
Overgeneralizing and giving advices based on your experience, i.e. "drive in % and forget about it", is actually a bad and dangerous advice to people who have no experience with the car.

Regarding "drive in % and forget about it" and your observations against that technique due to driving over 200 miles at or above posted highway speeds...

I always leave it in %, but I don't "forget about it".

Back in the olden days, with V8, if one had a destination in the nav system, the estimated % SOC at destination icon was always visible, posted right next to the destination ETA.

It was beautiful.

The most important metric for the whole leg was always there, next to the ETA.

I could start a long trip and periodically (but regularly) observe that estimated %SOC at destination icon without any additional actions on my part.

If that number started to drop, I would drop my speed 10 kph (5 mph) (assuming there were NO recharge options available between my current position and my destination).

If the number still dropped, I would drop speed another 10 kph and so on.

Conversely, if the estimated %SOC started to climb, I would have the option to increase my speed in increments.

Now, since V9, the estimated %SOC at destination information has been relegated to a silly stand alone page somewhere other than next to the active ETA.

Since V9, my technique is to start the journey with the nav system up and running and then touch the current leg navigation instructions to present (and freeze in place) "the whole trip".

Doing so presents the estimated % SOC remaining at destination icon information next to the ETA.

I then drive my trip at speeds that keep that estimated %SOC where I want it to be.

The point I'm making is one doesn't require the estimated range information displayed at any time, even on a long leg, because the only information that matters on a long leg is how much SOC you expect to have upon arrival.

As an example, yesterday I drove a 456 km round trip at speeds between 110kph and 135 kph.

I wanted to arrive at an intended destination at 20% SOC.

The trip started at 110 kph and as my trip progressed, I increased my speed based on what my estimated % SOC remaining at destination number was doing.

Once it stabilized at the figure I wanted, I increased my speeds such that the last hour was at 135 kph.

I had no idea what the remaining range number would have said.

I didn't care because the remaining range number was superfluous...all that mattered was arriving at a certain place with a specific %SOC remaining.

I'm firmly in the "use % remaining" camp...it avoids all the temperature change/charge techniques/software update stuff that plays havoc with the remaining range number.

I'd only use the remaining range number if the BMS was never subject to updates and I was always operating the vehicle at mean sea level, with an atmospheric pressure of 29.92 inches, at a temperature of 15C, with no wind, with no precipitation, on level ground and with no road compound changes.

 

[pdx_m3s]

Regarding "drive in % and forget about it" and your observations against that technique due to driving over 200 miles at or above posted highway speeds...

I always leave it in %, but I don't "forget about it".

Back in the olden days, with V8, if one had a destination in the nav system, the estimated % SOC at destination icon was always visible, posted right next to the destination ETA.

It was beautiful.

The most important metric for the whole leg was always there, next to the ETA.

I could start a long trip and periodically (but regularly) observe that estimated %SOC at destination icon without any additional actions on my part.

If that number started to drop, I would drop my speed 10 kph (5 mph) (assuming there were NO recharge options available between my current position and my destination).

If the number still dropped, I would drop speed another 10 kph and so on.

Conversely, if the estimated %SOC started to climb, I would have the option to increase my speed in increments.

Now, since V9, the estimated %SOC at destination information has been relegated to a silly stand alone page somewhere other than next to the active ETA.

Since V9, my technique is to start the journey with the nav system up and running and then touch the current leg navigation instructions to present (and freeze in place) "the whole trip".

Doing so presents the estimated % SOC remaining at destination icon information next to the ETA.

I then drive my trip at speeds that keep that estimated %SOC where I want it to be.

The point I'm making is one doesn't require the estimated range information displayed at any time, even on a long leg, because the only information that matters on a long leg is how much SOC you expect to have upon arrival.

As an example, yesterday I drove a 456 km round trip at speeds between 110kph and 135 kph.

I wanted to arrive at an intended destination at 20% SOC.

The trip started at 110 kph and as my trip progressed, I increased my speed based on what my estimated % SOC remaining at destination number was doing.

Once it stabilized at the figure I wanted, I increased my speeds such that the last hour was at 135 kph.

I had no idea what the remaining range number would have said.

I didn't care because the remaining range number was superfluous...all that mattered was arriving at a certain place with a specific %SOC remaining.

I'm firmly in the "use % remaining" camp...it avoids all the temperature change/charge techniques/software update stuff that plays havoc with the remaining range number.

I'd only use the remaining range number if the BMS was never subject to updates and I was always operating the vehicle at mean sea level, with an atmospheric pressure of 29.92 inches, at a temperature of 15C, with no wind, with no precipitation, on level ground and with no road compound changes.

This is not a personal jab, but what you just described is the definition of range-anxiety. I think perhaps you’re over thinking this whole thing in situations where it’s really not warranted.

 

[KenC]

my only problem with that is in an ICE...full tank when new and full tank 10yrs down the road will pretty much drive about same distance. With EV....100% brand new and 100% even 5yrs later will NOT drive the same distance....especially at the rate the model 3 batteries seem to be degrading. Sure some will argue that ICE become less efficient as they age...but IMO it’s nothing significant enough to notice a decrease in range. A gas tank will always hold the same capacity of gas. A lithium battery will not always hold the same capacity of charge. Degradation will have a bigger impact on net range than any decrease in efficiency of an ICE.

LI can get windy out to Montauk. Maybe you had a headwind.

 

[N54TT]

LI can get windy out to Montauk. Maybe you had a headwind.

It’s possible. I wasn’t paying attention to the direction of the wind. I didn’t notice any wind/breeze during the couple small stops we took....that I’ve also stopped at previous trips. And it definitely wasn’t as windy at the beach...if anything it was a calmer day. I think it’s mostly due to the 30 mile decrease in stated range.

 

[smatthew]

Can’t find it with google. Can any1 link it for me?

Even if you find the pastebin link the dropbox files it links to was taken down over a month ago.

 

[Twiglett]

my only problem with that is in an ICE...full tank when new and full tank 10yrs down the road will pretty much drive about same distance.

errr - in most cases it is demonstrably NOT the case.
Most ICE cars after 10 years do not get anything like the same MPG compared to new, same for power output.
An ICE is degrading from the moment it is first run.

 

[grmdl3]

errr - in most cases it is demonstrably NOT the case.
Most ICE cars after 10 years do not get anything like the same MPG compared to new, same for power output.
An ICE is degrading from the moment it is first run.

Apples and oranges are being compared by both sides. An ICE takes time to break in and achieve full efficiency, particularly a diesel. An EV is a whole different fruit which should come with different expectations.

 

[mrgoogle]

You have some good points, but that part - "rate the model 3 batteries seem to be degrading " is misleading.

Most reports you read of "fast degradation" are not really real degradation, but a misscalculation of the BMS. The BMS on Model 3 works differently than old Model S and X due to chemistry and pack density and connection of the cells. So the way you charge it is very important in order to have a good and balanced BMS. It has nothing to do with real degradation of the cells and the chemistry.

This information get's lost in the noise here on the forums, but charging the car only small increments leads to messed up BMS hence "degradation". We have thousands upon thousands of reports on this.
Mostly this is due to having the car "always plugged in" and driving short trips each day and charging back - like "the manual suggests".

I had a guy who apperently went with almost 0% degradation, but he was just charging 40%-60%. Once he charge 10 - 90 to 100% a couple of times he saw the real state of the car and the range dropped.

Having said that, the real degradation on the Model 3 is pretty small. I am at 20,000 miles and 1 year and have about 3% real, measured degradation. I charge very frequently almost top to almost bottom, so the car probably has a good idea of what is top to bottom and what the capacity is. I have also driven the top to almost bottom to confirm the numbers as in this video below.

So whatever you read about big degradation - don't. You can expect maximum of about 12-13% at 200,000 miles, 10% at about 150,000 miles and about 4-5% at 50,000 miles. That is common among most cars I see, give or take 1%.

Also, regarding the % vs miles thing on display.

We always hear from folks - I keep my car at % and never bother. Sure, if you have LR and only drive 100 miles a day and have a charger in your garage, I wouldn't care either.
But that applies to you and certainly doesn't apply to me - driving 200 miles at above US highway speeds, I need to know my range.

Try taking the car outside of the Supercharger network, with less chargers and try to squeeze out 250-280 miles from it on a single run, then you will begin to care. But then you will be mostly screwed, because you wouldn't know if the BMS is inbalanced, what the capacity of the car is and wether you can actually acchieve that.

You will also not know, what I show in the video below - mainly how to calculate the range based on the consumption and how tesla hides about 5% below 0. So by the time you see the % dropping fast, it will be too late.

So to summarize - driving EVs is, at least for now, still something that is not equal to all parties involved - due to different needs and the lack of great infrastructure (it is good, but still not great)
Overgeneralizing and giving advices based on your experience, i.e. "drive in % and forget about it", is actually a bad and dangerous advice to people who have no experience with the car.

I’ve read your posts throughout the board before. I’m well aware of the balanced BMS vs actual degradation debate. I’ve done the suggested methods to try and balance my BMS. It hasn’t really budged what SMT reports, which is 15% after 24k miles. There are plenty of posts and people I’ve spoken to with the same decrease in displayed range. I’m not trying to mislead people. In the end...for all intensive purposes....be it unbalanced BMS or real degradation....end user experience is a daily decrease in actual range. In hindsight I could have worded it differently.

Dude I know. I have the same. 8.5 of the 9 months we own our Model 3 SR+ it’s lacking -11 to -14% capacity.

When I bring this up to Tesla they won’t help you because no error. They tell you rated range is variable, bms needs calibrations, lecture about outside temps, tire pressure, car doesn’t measure heater energy, used energy isn’t accurate, drive even slower then speedlimit...

All bullshit and excuses in three different Tesla service centers in NL. I am also pretty sure you have the right to know battery health.

And yes I have frequently driven from 90, 100% to 5% and charged back up. I never charge small narrow charges.

Want to test for yourself how rediculous it is? Ask what State of Health is exactly next time when you are at service, Tesla will tell you it’s secret. (Even though I/you own the car!)

Funny thing is they tell you it actually would cost you money to get it checked! Even when they can see true capacity, but they won’t tell you capacity..

Our SR+ is usually around 208 /240 rated miles. Been like this when we got it, effectively never has been a SR+

ScanMyTesla shows I have 44.8 kWh available capacity at 100% charge. With a 0.5kWh heatloss that means max 39.7 kWh useable with a 90% charge. Buffer is 2.1kWh

(new full pack is 54.45kWh, ours is 46.x at best)

I really don’t want to as a shareholder, but after my “cooling down” (furious) I might explore legal options..

If that doesn’t work you’ll see my personally made Documentary (I built my own E-moped, programmed it, know how BMS work, ex- electric-cartechnician and I can edit videos pretty well also!)

 

[navguy12]

This is not a personal jab, but what you just described is the definition of range-anxiety. I think perhaps you’re over thinking this whole thing in situations where it’s really not warranted.

No jab taken.

I do think that folks that insist on using the range remaining display end up over thinking their situation.

 

[TimothyHW3]

I’ve done the suggested methods to try and balance my BMS. It hasn’t really budged what SMT reports, which is 15% after 24k miles.

And what are these so called "suggested" methods?! My suggested method is to ALWAYS charge from 10%-90%, have you followed through it for at least 2-3 months? You will get a slightly more real degradation, but your BMS will always be balanced.

Charge your car 10%-90% (drop it to 10%, plug right in, charge it to 90%, plug right out and start driving) for at least 3 consecivite months and I mean really - charge always in that range (or similiar, 10/20-80% if that isn't possible, like on a road trip or something where you can't time it) then report back after 3 months.

If you again see "15%" after 3 months then there is something wrong - take it to Tesla and have them check the cells. 15% after 24k miles is not only nearly impossible, I haven't yet seen a car with such "real" degradation.
My car is at 20K miles and has a little over 74.5kWh nominal full. That is about 3% give or take...

 

[TimothyHW3]

Our SR+ is usually around 208 /240 rated miles. Been like this when we got it, effectively never has been a SR+

240 miles is the rated range, so not sure what you are complaining about there if you get 240 miles?!

(new full pack is 54.45kWh, ours is 46.x at best)

No, new packs are 52 - 52.5kWh if you are lucky. You have SMT you should've tested when new.

ScanMyTesla shows I have 44.8 kWh available capacity at 100% charge.

Nominal full is 44.8 or deducted from the 2.1kWh? Meaning nominal full 46.9?

Obviously small batteries that are driven largely from 90% down will suffer more degradation but 44.8 is not normal. Even if it is 47kWh nominal full it is still a bit low, but I have already seen some SR+ with 47kWh in the wild.

Do you charge a lot on DC/Superchargers? How exactly do you charge?
Look back at the last 10 charging sessions and list them here and we might find what is wrong with it.
It doesn't have to be exact to the 2nd % precission, but everybody remembers where and how they charged at least the last 5 times. So basic stuff like "I charged AC at 11kW at home from around 15% to 55%" or I charged at Supercharger from 5 to 80% etc. will help.

Once I have the data I can see what might be the issue. But the same applies as before - charge the car for at least 2 months consistently from 10% to 90% and report back.

And before someone says - I never needed to write down my sessions on an ICE - true, but the ICE doesn't have BMS...And they have other issues you can't track...On an EV you just have to remember to keep basic charging principles and you are set. No oil changes, no oil checks, no motor belts after 70,000km no whistles...Just remember to charge properly. If that is too much for you, oh well...

You can either help yourself out and remember a few sessions, or go whine at the tesla service center - your choice.

 

[Zoomit]

My suggested method is to ALWAYS charge from 10%-90%, have you followed through it for at least 2-3 months? You will get a slightly more real degradation, but your BMS will always be balanced.

Referring to the BMS as “balanced” is confusing and inaccurate. Your method seems to be focused on calibrating the BMS.

Charge your car 10%-90% (drop it to 10%, plug right in, charge it to 90%, plug right out and start driving) for at least 3 consecivite months

This might work, but the Model 3 Service Manual, quoted in a previous post, indicates a better approach would be to let the battery rest before and after drives for “a long time” to provide more accurate calibration data. Here is the relevant graphic and text:

“This calculation is done whenever there is a drive or charge cycle however values are only stored when the calculation is deemed accurate. There are many complex parameters that factor into the accuracy of that number, and the HVBMS decides when the number is accurate enough to update CAC. One of these parameters is rest time before and after the drive/charge cycle. Notice in the figure above that the SOC was flat for a long time before and after the drive, this results in the most accurate voltage/SOC measurement which makes the CAC calculation accurate. Therefore in a worst case example, if a driver constantly charged and drove without ever letting the vehicle rest at a fixed SOC, then CAC algorithm will not update during that time.”​

 

[smatthew]

If you have SMT, what does it show for pack imbalance?

 

[Gasaraki]

Regarding "drive in % and forget about it" and your observations against that technique due to driving over 200 miles at or above posted highway speeds...

I always leave it in %, but I don't "forget about it".

Back in the olden days, with V8, if one had a destination in the nav system, the estimated % SOC at destination icon was always visible, posted right next to the destination ETA.

It was beautiful.

The most important metric for the whole leg was always there, next to the ETA.

I could start a long trip and periodically (but regularly) observe that estimated %SOC at destination icon without any additional actions on my part.

If that number started to drop, I would drop my speed 10 kph (5 mph) (assuming there were NO recharge options available between my current position and my destination).

If the number still dropped, I would drop speed another 10 kph and so on.

Conversely, if the estimated %SOC started to climb, I would have the option to increase my speed in increments.

Now, since V9, the estimated %SOC at destination information has been relegated to a silly stand alone page somewhere other than next to the active ETA.

Since V9, my technique is to start the journey with the nav system up and running and then touch the current leg navigation instructions to present (and freeze in place) "the whole trip".

Doing so presents the estimated % SOC remaining at destination icon information next to the ETA.

I then drive my trip at speeds that keep that estimated %SOC where I want it to be.

The point I'm making is one doesn't require the estimated range information displayed at any time, even on a long leg, because the only information that matters on a long leg is how much SOC you expect to have upon arrival.

As an example, yesterday I drove a 456 km round trip at speeds between 110kph and 135 kph.

I wanted to arrive at an intended destination at 20% SOC.

The trip started at 110 kph and as my trip progressed, I increased my speed based on what my estimated % SOC remaining at destination number was doing.

Once it stabilized at the figure I wanted, I increased my speeds such that the last hour was at 135 kph.

I had no idea what the remaining range number would have said.

I didn't care because the remaining range number was superfluous...all that mattered was arriving at a certain place with a specific %SOC remaining.

I'm firmly in the "use % remaining" camp...it avoids all the temperature change/charge techniques/software update stuff that plays havoc with the remaining range number.

I'd only use the remaining range number if the BMS was never subject to updates and I was always operating the vehicle at mean sea level, with an atmospheric pressure of 29.92 inches, at a temperature of 15C, with no wind, with no precipitation, on level ground and with no road compound changes.

That is exactly how I drive. Use the car's map guesstimate (because that's accurate based on your battery state and elevations), energy graph, and control usage using speed. If I want to get to my destination with 10% left and I see the map estimate is dropping, I know I need to stop racing people.

If I do suddenly get more buffer, I know that I can go a little faster. Now I'm not saying I drive slow to begin with. I drive at 75 and adjust up or down from there.