Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[AAKEE]

Sorry to disappoint you, but although I don't believe nearly anything I read, I don't keep track of the stories I do. It's the internet, not a dissertation. All I can tell you is the range on my LR was WAAAAY lower than advertised under every condition, so seemed plausible to me. And could have been that 'buffer', for all I know. And Apple was sued (and settled out of court, and offered owners free battery replacement... which I got) for doing something to decrease battery life, to force owners to upgrade to a new phone. If you care that much about both stories, search. And VW cheated with the diesel emissions, and got caught too. Unless you're in kinder garten, it's nothing new.

I do mot know if you know but to make this sure:

- EV manufacturers must presebt the range acvording to EPA. There are a possibility to make a volantary Reduction, but if the test shows for example 315 miles, then the car will do this on the dsy of delivery.

- The EPA (and WLTP) test is performed at 23C with the AC off. (My logged data for both cars show the longest range between 20 abd 25C so it is actually on the best temperature for an EV).

-The range is not tested at 80mph constant speed. The aversge speed is much less.

- Batteries degrade heavily the first year, specially the first six months. If ypu are a average EV owner, you loose ~ 5% the firdt year = 5% range lost.

If you take your brand new car and drive in +23C with the AC off at 55mph on telatively flat ground you’ll be able to drive the EPA range. As the EPA range is tested until the car stops you also need to drive until the car stops. In this case, you need to distegard the 0% displayed as you still have a out 4.5% below that to drive on.

I did slightly more than the EPA range after my car was 1.5 yrs and about 40K km.
Got 319 miles/513km out of the 315mi/507km EPA range.
I actually drove the first half (240km to work) exactly by the speed limit, and on the way home I used the cruise control spreed set to estimate to arrive at home with 0% indicated. The last 30km it was dense fog so I had to refuce the speed. I ended up driving another 33km around town to get to 0%.

 

[conv90]

Just an Update on my 2021 Model 3 Performance (E3LD 82,1 kWh Panasonic Battery)
Scan My Tesla Nominal full Pack graph taken daily from day 0ne (13/03/2021) to today.

 

[AAKEE]

Just an Update on my 2021 Model 3 Performance (E3LD 82,1 kWh Panasonic Battery)
Scan My Tesla Nominal full Pack graph taken daily from day 0ne (13/03/2021) to today.
View attachment 1000639

If I remember it correct you where unhappy in an early stage about high appearent degradation?
I guess you use the low SOC strategy based on the numbers we see now…
Your battery average somewhere around 78 kWh right now (but with huge oscillations). Looks good and also as expected with the low SOC strategy.
The oscillations must be the BMS that are dreaming of driving to the Mediterranean and taking a bath rather than keeping track of the bsttery capacity

My battery in my M3P would be about 78kWh right now (sold the car, but the degradation followed the square root tight so… ). My BMS is also probably thinking of driving to the Mediterranean and taking a bath, rather than be stuck here close to Santa and being cold together with the battery

 

[Steve446]

Just an Update on my 2021 Model 3 Performance (E3LD 82,1 kWh Panasonic Battery)
Scan My Tesla Nominal full Pack graph taken daily from day 0ne (13/03/2021) to today.
View attachment 1000639

Your plot is interesting and nice data, particularly the biggest change in the middle left of the graph! The question is what provoked the changes? Do you have any other SMT data? I would be interested to see what happens to the graph if you,
1. Put markers every time (if and when) you dropped SoC to "0" display value and charged to 100%
2. Supercharged
3. You added full rated range taken at the same time as the NFP data taken from SMT (if you have it).

Also your Y axis range is large (70-81 =~13-14% of full scale which tends to exagerate the peak to trough heights. My own NFP, delivery to present, does not seem to have done that, and varies around 3-5 % full scale. plus or minus (it's an LG M48 NCM). I take the liberty of suggesting taking a monthly average on the data might give you a better feel for the capacity decrease, although degradation looks like 77.2/82.1=6%? (if I use your FPWN and my by eye estimated current average value).

 

[conv90]

If I remember it correct you where unhappy in an early stage about high appearent degradation?
I guess you use the low SOC strategy based on the numbers we see now…
Your battery average somewhere around 78 kWh right now (but with huge oscillations). Looks good and also as expected with the low SOC strategy.
The oscillations must be the BMS that are dreaming of driving to the Mediterranean and taking a bath rather than keeping track of the bsttery capacity

My battery in my M3P would be about 78kWh right now (sold the car, but the degradation followed the square root tight so… ). My BMS is also probably thinking of driving to the Mediterranean and taking a bath, rather than be stuck here close to Santa and being cold together with the battery

I add: 61000 km.
Yes, usually I charge for what I need for 2 or 3 days. SO, When I'm able to charge regularly from 20-22-25-28% to 60% the NFP goes UP.
When I change style , the BMS reacts
And Yes I'ts me. I was Unhappy because of 79,6 kWh when new and 73,9 kWh 11 months later.

 

[conv90]

Your plot is interesting and nice data, particularly the biggest change in the middle left of the graph! The question is what provoked the changes? Do you have any other SMT data? I would be interested to see what happens to the graph if you,
1. Put markers every time (if and when) you dropped SoC to "0" display value and charged to 100%
2. Supercharged
3. You added full rated range taken at the same time as the NFP data taken from SMT (if you have it).

Also your Y axis range is large (70-81 =~13-14% of full scale which tends to exagerate the peak to trough heights. My own NFP, delivery to present, does not seem to have done that, and varies around 3-5 % full scale. plus or minus (it's an LG M48 NCM). I take the liberty of suggesting taking a monthly average on the data might give you a better feel for the capacity decrease, although degradation looks like 77.2/82.1=6%? (if I use your FPWN and my by eye estimated current average value).

1) I discharged often to sub 0% . But I never charged immediately after to 100%. I charged often to 100% , but usually on trips .
But, when I dropped it to 0% (or when I charged to 100%) I never noticed a direct influence on NFP. (at least not in the next immediate period).
Nor the temp is a signal to trigger the nfp high or low. It's only the low charge method.
2) there is no difference if I charge from SUpercharger or AC. What make the NFP raise is the 20-30% to 60% charge and never let it sleep over 55%
3) there is always a direct correlation between NFP of the graph and the rated range. Now it's 78,6 and the full rated rage is 497 km and when it was 79,9 at 11 20th November 2023 it was 505.

 

[Bouba]

My car is a 2021 M3LR MiC 75 kWh LG with about 3% degradation and 25,000 km….and my 100% range is now 520 km

 

[Steve446]

My car is a 2021 M3LR MiC 75 kWh LG with about 3% degradation and 25,000 km….and my 100% range is now 520 km

Hi Bouba, can you give your initial max range ?

It would be interesting to estimate if your FPWN is around the same as mine was.

Here are the first 4 weeks from my M3 (same as your car's spec):

544

540

538

539

After 19500 kM here's my FRR:

530

529

528

530

528

529

 

[JCtx]

- The EPA (and WLTP) test is performed at 23C with the AC off. (My logged data for both cars show the longest range between 20 and 25C so it is actually on the best temperature for an EV)...

Thank you for the great info you posted. I obviously knew before buying it that we'd never see anything close to EPA ratings for all the factors you mentioned. And I also understand full range either on an EV or gas car, is just not achievable, since I'd NEVER run out of fuel/charge to get it (not even close). But we were surprised of the actual numbers, especially traveling in the cold of winter, basically getting about 200 miles of range (@ 80/85, in TX, and heater on). But I never complain about that kind of thing (and neither on gas car mileage/range); I just adjust to the reality (if I can), and live with it. Complaining to a dealer I'm not getting 'x' range doesn't even cross my mind, since I know I wouldn't get anywhere anyway, especially if there's nothing wrong with the vehicle (which is the case the ultra great majority of times of such complaints). You just have to realize those numbers are ideal, and you'd never see them. Another disappointment was charging. We thought 150kWh charging would be minimal, but unfortunately, it doesn't work that way. I never saw 150kW, because I never arrived below 20% charge (on purpose, to have a buffer for accidents, detours, etc). So charging delayed us TWO HOURS more than normal from ELP to AUS (exactly 600 miles), so we had to relegate the new M3LR to 'city car' only, which wasn't the plan at the time. So when the opportunity came to sell it at an actual profit of $3K (after taxes, accessories, and even the home charger) after 1 year and 10K miles, we jumped on that. It was a very informative test-drive. Ha ha. So I'd be jumping into ownership of the M3P with full knowledge of its advantages and shortcomings, thanks to this wonderful forum. Thanks again for all the help.

 

[Bouba]

Hi Bouba, can you give your initial max range ?

It would be interesting to estimate if your FPWN is around the same as mine was.

Here are the first 4 weeks from my M3 (same as your car's spec):

544

540

538

539

After 19500 kM here's my FRR:

530

529

528

530

528

529

I never wrote it down but I do remember....when I first got the car it was 542 km @100%....as the months went by it slowly increased to over 550 km...maybe upto 555 kms.....then I went on a road trip to Italy and used Superchargers and destination chargers....when I got back home the car quickly readjusted itself to 530 + .....and stayed steady until another road trip, this time to England...when I returned it steadily reduced to about 520 and it’s stayed there now for the past few months

 

[Steve446]

I never wrote it down but I do remember....when I first got the car it was 542 km @100%....as the months went by it slowly increased to over 550 km...maybe upto 555 kms.....then I went on a road trip to Italy and used Superchargers and destination chargers....when I got back home the car quickly readjusted itself to 530 + .....and stayed steady until another road trip, this time to England...when I returned it steadily reduced to about 520 and it’s stayed there now for the past few months

Thanks for the update. Yep sounds pretty much the same as my M3 (74.5 kWh FPWN). I've just done a road trip to the UK too beginning December and I get the impression that the NFP has slipped down a little bit more... To see in the next 2-3 months!

 

[Bouba]

Thanks for the update. Yep sounds pretty much the same as my M3 (74.5 kWh FPWN). I've just done a road trip to the UK too beginning December and I get the impression that the NFP has slipped down a little bit more... To see in the next 2-3 months!

My impression is that slow charging at home (I only have a normal three pin plug) doesn’t upset the BMS....but when you plug it into a Supercharger it makes it reevaluate its life
Just out of interest I haven’t tried any form of battery recovery....I’ve never taken it down to zero and then up to 100%

 

[Steve446]

Thank you for the great info you posted. I obviously knew before buying it that we'd never see anything close to EPA ratings for all the factors you mentioned. And I also understand full range either on an EV or gas car, is just not achievable, since I'd NEVER run out of fuel/charge to get it (not even close). But we were surprised of the actual numbers, especially traveling in the cold of winter, basically getting about 200 miles of range (@ 80/85, in TX, and heater on). But I never complain about that kind of thing (and neither on gas car mileage/range); I just adjust to the reality (if I can), and live with it. Complaining to a dealer I'm not getting 'x' range doesn't even cross my mind, since I know I wouldn't get anywhere anyway, especially if there's nothing wrong with the vehicle (which is the case the ultra great majority of times of such complaints). You just have to realize those numbers are ideal, and you'd never see them. Another disappointment was charging. We thought 150kWh charging would be minimal, but unfortunately, it doesn't work that way. I never saw 150kW, because I never arrived below 20% charge (on purpose, to have a buffer for accidents, detours, etc). So charging delayed us TWO HOURS more than normal from ELP to AUS (exactly 600 miles), so we had to relegate the new M3LR to 'city car' only, which wasn't the plan at the time. So when the opportunity came to sell it at an actual profit of $3K (after taxes, accessories, and even the home charger) after 1 year and 10K miles, we jumped on that. It was a very informative test-drive. Ha ha. So I'd be jumping into ownership of the M3P with full knowledge of its advantages and shortcomings, thanks to this wonderful forum. Thanks again for all the help.

Very pragmatic.
I have a couple of comments.
1) Everybody talks about using % battery instead of actual RR, I totally agree and do too. But why all this debate about EPA and WLTP range and driving down below zero screen display (with all the risks involved) etc, Honestly who cares, the real world range is what it is. I know from my seasonally adjusted Wh/kM that I have a real world range of about 440-470 kM on a full charge (all time Wh/kM is 156-158 /kM). I relate that to 44-47 kM per 10% battery, after that it's easy to know how far I can drive. So yes, more complicated than just using a nice pretty range figure on the screen , yes of course, but, pretty bullet proof for me.
2) I've read a lot of BS about M3 charging rates. The reality is that for me and my LG M48 battery is that it tops out at around 144 KWh (see the graph of my SuC session on December 01, it's typical for the SoC range concerned (18 --> 96%). The SuC concerned was a shared power source but I was the only user at the time of charging.

 

[Steve446]

My impression is that slow charging at home (I only have a normal three pin plug) doesn’t upset the BMS....but when you plug it into a Supercharger it makes it reevaluate its life
Just out of interest I haven’t tried any form of battery recovery....I’ve never taken it down to zero and then up to 100%

I have some data on that and will dig it out tomorrow.

 

[Steve446]

1) I discharged often to sub 0% . But I never charged immediately after to 100%. I charged often to 100% , but usually on trips .
But, when I dropped it to 0% (or when I charged to 100%) I never noticed a direct influence on NFP. (at least not in the next immediate period).
Nor the temp is a signal to trigger the nfp high or low. It's only the low charge method.
2) there is no difference if I charge from SUpercharger or AC. What make the NFP raise is the 20-30% to 60% charge and never let it sleep over 55%
3) there is always a direct correlation between NFP of the graph and the rated range. Now it's 78,6 and the full rated rage is 497 km and when it was 79,9 at 11 20th November 2023 it was 505.

Thank you for the details @conv90 ! Doesn't seem like my car, weird that 20-60%. Not the same battery I realize. So, 158 Wh/kM similar to my M3 from your data of Nov 20. I've seen a greater impact of charging to 100% from time to time. I'll dig that graph out tomorrow.

 

[AAKEE]

But why all this debate about EPA and WLTP range and driving down below zero screen display (with all the risks involved) etc, Honestly who cares, the real world range is what it is.

Did you miss the question that we answered ?

Sometimes when people are dissatisfied with the real world range and may even feel cheated on by Tesla as they did read that the car they later bought had 3X0 miles range, it might be wise to explain how the EPA range is constructed and tested, which means charging full and then driving until the car stops, which means driving up the buffer.
This do not mean that we recommend to drive until the car stops.

Sorry to disappoint you, but although I don't believe nearly anything I read, I don't keep track of the stories I do. It's the internet, not a dissertation. All I can tell you is the range on my LR was WAAAAY lower than advertised under every condition, so seemed plausible to me. And could have been that 'buffer', for all I know. And Apple was sued (and settled out of court, and offered owners free battery replacement... which I got) for doing something to decrease battery life, to force owners to upgrade to a new phone. If you care that much about both stories, search. And VW cheated with the diesel emissions, and got caught too. Unless you're in kinder garten, it's nothing new.

I think @JCtx was happy about the description, and hopefully he is less dissapointed with the real world range now.

 

[AAKEE]

I never wrote it down but I do remember....when I first got the car it was 542 km @100%....as the months went by it slowly increased to over 550 km...maybe upto 555 kms.....then I went on a road trip to Italy and used Superchargers and destination chargers....when I got back home the car quickly readjusted itself to 530 + .....and stayed steady until another road trip, this time to England...when I returned it steadily reduced to about 520 and it’s stayed there now for the past few months

Yes, the smaller LG thats actually marked 74.5 kWh full pack when new alos climbed slightly above the 74.5kWh, like 75-75.5 or so.
The charging constant is 137.15 or so Wh/km for the 2021/2022 LR so 74.5kWh = 543km-ish. I have seen 550-551km.

 

[Steve446]

Did you miss the question that we answered ?

Sometimes when people are dissatisfied with the real world range and may even feel cheated on by Tesla as they did read that the car they later bought had 3X0 miles range, it might be wise to explain how the EPA range is constructed and tested, which means charging full and then driving until the car stops, which means driving up the buffer.
This do not mean that we recommend to drive until the car stops.


I think @JCtx was happy about the description, and hopefully he is less dissapointed with the real world range now.

No I got the points that were raised and understand the fustration of many EV owners on this issue. You have nicely, clearly and without doubt, helped clarify those irritations with your explanation. I'm not convinced that the problem will go away anytime soon though. But - I am sure you will agree that the issue is certainly wider than just a Tesla thing after all and a problem frequently misunderstood by a significant portion of EV owners and as far as I can tell, some professional testers across available brands. That's why I made my point about what counts is after all, simple real world range and not the different range tests and sometimes displaced opinions of the different online car blogs concerned.

 

[navguy12]

Thank you for the great info you posted. I obviously knew before buying it that we'd never see anything close to EPA ratings for all the factors you mentioned. And I also understand full range either on an EV or gas car, is just not achievable, since I'd NEVER run out of fuel/charge to get it (not even close). But we were surprised of the actual numbers, especially traveling in the cold of winter, basically getting about 200 miles of range (@ 80/85, in TX, and heater on). But I never complain about that kind of thing (and neither on gas car mileage/range); I just adjust to the reality (if I can), and live with it. Complaining to a dealer I'm not getting 'x' range doesn't even cross my mind, since I know I wouldn't get anywhere anyway, especially if there's nothing wrong with the vehicle (which is the case the ultra great majority of times of such complaints). You just have to realize those numbers are ideal, and you'd never see them. Another disappointment was charging. We thought 150kWh charging would be minimal, but unfortunately, it doesn't work that way. I never saw 150kW, because I never arrived below 20% charge (on purpose, to have a buffer for accidents, detours, etc). So charging delayed us TWO HOURS more than normal from ELP to AUS (exactly 600 miles), so we had to relegate the new M3LR to 'city car' only, which wasn't the plan at the time. So when the opportunity came to sell it at an actual profit of $3K (after taxes, accessories, and even the home charger) after 1 year and 10K miles, we jumped on that. It was a very informative test-drive. Ha ha. So I'd be jumping into ownership of the M3P with full knowledge of its advantages and shortcomings, thanks to this wonderful forum. Thanks again for all the help.

I drive a steam driven, vacuum tube powered (May 2018) TM3.

I have a routine commute between Ottawa and Guelph (ON), winter and summer.

In the winter, my routine westbound stop is at the Peterborough supercharger, which results in a 22 minute (+/-) charge session (while I use the facilities and have a bite to eat).

In the summer, that same stop is about 14 minutes.

The return trip home requires the supercharger in Madoc (ON).

Winter is a 15 minute (+/-) session and summer is a six minute session.

I’m at the age where 2.5 hours is the maximum time between restroom breaks, so long distance driving in my old EV works just fine

 

[JCtx]

I think @JCtx was happy about the description, and hopefully he is less disappointed with the real world range now.

Your description was awesome, and I'm sure will help many newbies. Thank you again. I was disappointed initially, but like I mentioned, I just adjusted to the reality, and was happy after that. It wasn't the car's fault; just lack of real world information... which you have to find the hard way, since we all have different ways to deal with range. Anyway, my reality (especially when traveling) was 2.5 miles per 1% charge, since I like to drive fast. And arriving with 30% charge (after one accident, involving a detour, where we made it with 10%, I was glad to have taken that conservative approach). So no need to let the car map anything, other than just getting the distance from supercharger to supercharger, which typically was about 125 miles. So I did my own calculations, and needed 50% charge to drive (125 / 2.5 = 50%), plus 30% buffer = 80% at the supercharger. And that's what we did. But it was quite a bit slower to charge than anticipated, so unfortunately, the car didn't work out as a travel car. So that was why we decided to sell it later on. We have a gas travel car now, so the new EV would just be a city car. I wanted to take it to the nearby mountains to have fun, but no superchargers there. Bummer.

Finally, I should be able to use the same 2.5 miles per 1% charge on the P IMO, but we'll see. It's a conservative figure, since it equates to a range of 250 miles. With A/C or heater on, and 80/85 speeds (or heavy acceleration in the city), it sounds about right to me. I'm pretty sure my lifetime power usage was less than 300 watts per mile, so a little conservative without the need for A/C or heater.

EDIT: Forgot to add that I never keep track of mileage or efficiency or cost to fuel/charge on any vehicle. I just fuel up (or charge) when needed. But with the limited range and charging options of the EV, I had to come up with a realistic (and conservative) figure, to know how much to charge at each supercharger with our set buffer of 30%. But I don't keep track of metrics, including degradation; it is what it is. Ha ha.