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

[AAKEE]

We paid for one thing, we got something. Not sure about the US, but in Australia this is against the law.

I don know about what system Aus use for advertising range.
EPA, thats the US Environment protection agency setting the norms for how to measure. Also, they clearly say the EPA range is for comparison and isnt the true range:

WLTP which Europe use claims to be like real driving but as the average speed is 53.5km/h you need to use a very low speed or have a huge part of the driving session att low speed to come close to this consumption and range.
WLTP is 12% more optimistic than EPA for my ’21 M3P.

Both EPA and WLTP use test temperature somewhere about 15c. The heater and AC is set to off. An electric car needs to use the bsttery energy to hest the car, or at least drive the heatpump with battery.

When wishing to reach EPA range, you need warm klimat, AC off and keep speed down to be within the EPA test range. And you need to drive it beyond 0% which isnt wise, but its possible to do it.
Colder climats with heat pump on will not reach the EPA range.
Colder climats with heat pump on will not reach the EPA range.

As for the degradation, no one can or should expect the car to keep the advertised range forever. The nature of electric batterys as we know it today is that they will degrade.

Degradation will depend on a lot of factors, so it will differ from car to car.
Heat x time degrade lithium batterys more. If you live in a warm climat and the car is at elevated ambient temperatures its battery will degrade faster then a cold climat, for the storage part of the battery degradation. If you can keep the bat at maximum 60% as the highest charge point and in cold conditions, itll degrade slow. Often needing to charge high plus combined with a hot climat will have a negative effect on the battery.

We know degradation is higher in the beginning of a battery life and then most often almost stops, and get very shallow if used as the average car. Model 3 seems to report slightly higher degradation than S/X but still this can be differences in the BMS.
We have the Teslabjorn on youtube that tested true battery degradation by driving got 8% degradation after 2 years / 80K km and he had some 64% AC/ supercharging which is suposed to be bad for the battery. His test was done during winter/cold climate and he guessed that a degradation test during summer would show lower degradation( perhaps 7%).

To sum it up, when switching from ICE cars to EV you need to adopt the nature of EVs, and probably it takes some time to get adopted. Id say, it is not Teslas or any other EV car makers job to assist you with all the facts. Even if they tried, most buyers would say “yayayaya, give me the key so I can go ‘n drive”.
What I see here and at another forum is people going into the EV world without have done the appropriate research before, which means they didnt really understand what they bought until after they got the car.

 

[Candleflame]

I don know about what system Aus use for advertising range.
EPA, thats the US Environment protection agency setting the norms for how to measure. Also, they clearly say the EPA range is for comparison and isnt the true range:
View attachment 649853

WLTP which Europe use claims to be like real driving but as the average speed is 53.5km/h you need to use a very low speed or have a huge part of the driving session att low speed to come close to this consumption and range.
WLTP is 12% more optimistic than EPA for my ’21 M3P.

Both EPA and WLTP use test temperature somewhere about 15c. The heater and AC is set to off. An electric car needs to use the bsttery energy to hest the car, or at least drive the heatpump with battery.

When wishing to reach EPA range, you need warm klimat, AC off and keep speed down to be within the EPA test range. And you need to drive it beyond 0% which isnt wise, but its possible to do it.
Colder climats with heat pump on will not reach the EPA range.
Colder climats with heat pump on will not reach the EPA range.

As for the degradation, no one can or should expect the car to keep the advertised range forever. The nature of electric batterys as we know it today is that they will degrade.

Degradation will depend on a lot of factors, so it will differ from car to car.
Heat x time degrade lithium batterys more. If you live in a warm climat and the car is at elevated ambient temperatures its battery will degrade faster then a cold climat, for the storage part of the battery degradation. If you can keep the bat at maximum 60% as the highest charge point and in cold conditions, itll degrade slow. Often needing to charge high plus combined with a hot climat will have a negative effect on the battery.

We know degradation is higher in the beginning of a battery life and then most often almost stops, and get very shallow if used as the average car. Model 3 seems to report slightly higher degradation than S/X but still this can be differences in the BMS.
We have the Teslabjorn on youtube that tested true battery degradation by driving got 8% degradation after 2 years / 80K km and he had some 64% AC/ supercharging which is suposed to be bad for the battery. His test was done during winter/cold climate and he guessed that a degradation test during summer would show lower degradation( perhaps 7%).

To sum it up, when switching from ICE cars to EV you need to adopt the nature of EVs, and probably it takes some time to get adopted. Id say, it is not Teslas or any other EV car makers job to assist you with all the facts. Even if they tried, most buyers would say “yayayaya, give me the key so I can go ‘n drive”.
What I see here and at another forum is people going into the EV world without have done the appropriate research before, which means they didnt really understand what they bought until after they got the car.

We are not talking about epa or wltp or whatever was used to advertise the car. We are just using it to talk about degradation and rated range is a good way to communicate this without constantly asking how many kwh, doing the calculations, explaining if its with buffer and whatnot. I actually frequently do hit epa consumption. I usually have tailwind going north and mainly travel on country lanes with lots of slow moving traffic everywhere and wildlife danger.

And we dont just spend 5min more charging on a roadtrip, throughout the coastline we can often just get 40kw fast charging and inland no fast charging at all, but we might get the odd true dc fast charger after 600-700km so you frequently roll in there at low SOC as you dont want to spend more time than necessary at an AC charger or slow DC charger.

The irony here is that the real range king in nonurban australia is still the old model s85 with its little degradation and 22kw monster ac charger - that can actually still drive at the speedlimit with ac charging only whereas the model 3 has to slow down to 85kph as you otherwise just spend longer charging. And yeah, long range travel with AC only sucks.
I usually leave in the evening and try to get a 100% ac charge while i sleep in the car and then drive that down in the morning and charge in the middle of the day for a few hours. Its not great. It is getting better and certainly the southern states are starting to get reasonably covered with at least 42kw but good luck anywhere north.

I regularly travel 1100km with just medium dc charging and do the odd 1300km inland too where i habe to bridge 1000km with ac only. Every km of degradation hurts there.

 

[AAKEE]

We are not talking about epa or wltp or whatever was used to advertise the car. We are just using it to talk about degradation and rated range is a good way to communicate

I started with 78.2kWh and now I have 69kWh batter with buffer. So that's 65kWh . If I could do the 142Wh/km that NEDC rating use, this would give me 442km range. And I will never achieve that range because no one caring about their car will go to 0% battery.

We paid for one thing, we got something. Not sure about the US, but in Australia this is against the law.

Please do not take this answer as critism:

My answer was due to jyavenard post. As I do read it, he isnt happy because he do not think he got the range he paid for.

If the car doesnt reach the advertised range when very new, following all the conditions in EPA, WLTP or NECD cycle, then you can say that you didnt get what you paid for. In other worlds, finding that the battery do not live up to the specified capacity(+/- a acceptable variation) or finding that the car uses much more Wh/km or mile than the advertisement (still 100% according to EPA, WLTP, NECD conditions) also could put you in the position to claim it doesnt reach the specs.
Tesla do not advertise battery size for model 3 so no one could to that claim. So, claiming the range isnt good is the only possible solution I see.(of course tesla would check the battery capacity anyway, but the deal you have is not kWh)
As long as the EPA certification/tests allows the buffer to be counted it is ok to use it, without lying. You can use it by driving to the car stops. Thats the range.

As for degradation the only thing tesla stands for is max 30% degradation(min 70% left) at the maximum mileage or maximum time as far as I know.
All other limits is probably made up in your own mind. Reading about model S or X low degradation and taking that s a promise that Model 3, with a completely new battery cell that of course try to reach new standards for high energy density, low cobalt usage and so on. As long as you do not wait until you know that it has very low degradation, the risk of having to live with a higher degradation but below 30% is the one you have to take.

If you read test of lithium batterys, you will find that batterys degrade. We can not circumnavigate that fact. Temperature x time is one of the worst enemies, as high currents(both charging and discharging) . Deep cycles also cause degrading.
So, depending of where you live(temperature enviroment during the year), driving+charging habits, will cause quite big differences between peoples cars.

I live in northern sweden, winter time so I have +10-12C in the garage. daily drive is about 100km, I charge to 60%, and have the charging time set during night so it do not stand charged for that long. Usually 35-40% when Im back. Small cycles, charges to about sweet spot for storage and also standing in +10 to 12C. The battery even keeps about 12-15C during use so its more or less the ideal life for a lithium cell. When the car was new(a few days, about 1000km) I had 80,6kWh as nominal full in SMT. I did a full charge before a trip, and saw 81.1kWh, after this is quite quick went to 81.1, and it still shows 81.1kWh after 4 months and 7000km total. These conditions is perfect and if I could keep it I guess degradation would be very low. But as summer comes with higher temps the degradation probably is a bit higher.
I have quite much experience from using lithium batteries in other demanding applications, I will use this to try to keep the degradation low, but I will not make very big sacrifices, because this would take the fun out of having a M3 Performance and probably cause need to plan the life. I rather take a little more degradation than the minimum I could achieve.

 

[Zcd1]

Does it affect me on my daily driving? no.

Thank you for answering the question.

If you were expecting zero or negligible degradation, then you didn’t understand lithium battery technology or EVs when you made your purchase, which is a shame.

I hope you continue to enjoy your car regardless.

 

[Nayston]

First charge to 90% and I’m sitting at 282 miles. I can do math, and that seems way too low for the rated range on a car that is 1 day old. Am I wrong? Should I ignore it or mention something?

 

[diamond.g]

We are not talking about epa or wltp or whatever was used to advertise the car. We are just using it to talk about degradation and rated range is a good way to communicate this without constantly asking how many kwh, doing the calculations, explaining if its with buffer and whatnot. I actually frequently do hit epa consumption. I usually have tailwind going north and mainly travel on country lanes with lots of slow moving traffic everywhere and wildlife danger.

And we dont just spend 5min more charging on a roadtrip, throughout the coastline we can often just get 40kw fast charging and inland no fast charging at all, but we might get the odd true dc fast charger after 600-700km so you frequently roll in there at low SOC as you dont want to spend more time than necessary at an AC charger or slow DC charger.

The irony here is that the real range king in nonurban australia is still the old model s85 with its little degradation and 22kw monster ac charger - that can actually still drive at the speedlimit with ac charging only whereas the model 3 has to slow down to 85kph as you otherwise just spend longer charging. And yeah, long range travel with AC only sucks.
I usually leave in the evening and try to get a 100% ac charge while i sleep in the car and then drive that down in the morning and charge in the middle of the day for a few hours. Its not great. It is getting better and certainly the southern states are starting to get reasonably covered with at least 42kw but good luck anywhere north.

I regularly travel 1100km with just medium dc charging and do the odd 1300km inland too where i habe to bridge 1000km with ac only. Every km of degradation hurts there.

If anything, this shows that we should wait 2 years before jumping on vehicles with the new 4680 cells. Just to see what the degradation curve looks like. Relying on the curves from the S has really bitten us on the bum.

 

[DirtyT3sla]

The performance Model 3 is rated at 315 miles at a full charge. 315*0.9=283.5 so it seems pretty good to me.

 

[AAKEE]

Thank you for answering the question.

If you were expecting zero or negligible degradation, then you didn’t understand lithium battery technology or EVs when you made your purchase, which is a shame.

I hope you continue to enjoy your car regardless.

Well, maybe not a shame but not optimal.

If anything, this shows that we should wait 2 years before jumping on vehicles with the new 4680 cells. Just to see what the degradation curve looks like. Relying on the curves from the S has really bitten us on the bum.

Why ?

Just get a version with 30% range more than your maximum need. Then youre safe for 192000km/160000 miles.

In Sweden the warranty differs for M3 SR and LR/P. SR has the shortest warranty(160000km)

Model S/X has 240000km.

The warranty tell you a little a what to expect. Dont buy a SR, charge it to full every day + deep cycle it and expect it to hold up like a Model S Long Range battery. Because it most probably wont.

 

[Zcd1]

I'm not sure you've grasped the whole picture.

From my perspective, it's those complaining about degradation who failed to grasp the whole picture:

1. Lithium-ion batteries degrade.
2. Tesla's warranty (in the US, at least) guarantees >70% capacity at 8 years or 120,000 miles, whichever comes first.

No amount of tracking or worrying will change either of those facts, nor will a report from any 3rd party software/source.

Again, I hope the facts of the situation don't detract from your enjoyment of your car. Cheers.

 

[Candleflame]

Please do not take this answer as critism:

My answer was due to jyavenard post. As I do read it, he isnt happy because he do not think he got the range he paid for.

If the car doesnt reach the advertised range when very new, following all the conditions in EPA, WLTP or NECD cycle, then you can say that you didnt get what you paid for. In other worlds, finding that the battery do not live up to the specified capacity(+/- a acceptable variation) or finding that the car uses much more Wh/km or mile than the advertisement (still 100% according to EPA, WLTP, NECD conditions) also could put you in the position to claim it doesnt reach the specs.
Tesla do not advertise battery size for model 3 so no one could to that claim. So, claiming the range isnt good is the only possible solution I see.(of course tesla would check the battery capacity anyway, but the deal you have is not kWh)
As long as the EPA certification/tests allows the buffer to be counted it is ok to use it, without lying. You can use it by driving to the car stops. Thats the range.

As for degradation the only thing tesla stands for is max 30% degradation(min 70% left) at the maximum mileage or maximum time as far as I know.
All other limits is probably made up in your own mind. Reading about model S or X low degradation and taking that s a promise that Model 3, with a completely new battery cell that of course try to reach new standards for high energy density, low cobalt usage and so on. As long as you do not wait until you know that it has very low degradation, the risk of having to live with a higher degradation but below 30% is the one you have to take.

If you read test of lithium batterys, you will find that batterys degrade. We can not circumnavigate that fact. Temperature x time is one of the worst enemies, as high currents(both charging and discharging) . Deep cycles also cause degrading.
So, depending of where you live(temperature enviroment during the year), driving+charging habits, will cause quite big differences between peoples cars.

I live in northern sweden, winter time so I have +10-12C in the garage. daily drive is about 100km, I charge to 60%, and have the charging time set during night so it do not stand charged for that long. Usually 35-40% when Im back. Small cycles, charges to about sweet spot for storage and also standing in +10 to 12C. The battery even keeps about 12-15C during use so its more or less the ideal life for a lithium cell. When the car was new(a few days, about 1000km) I had 80,6kWh as nominal full in SMT. I did a full charge before a trip, and saw 81.1kWh, after this is quite quick went to 81.1, and it still shows 81.1kWh after 4 months and 7000km total. These conditions is perfect and if I could keep it I guess degradation would be very low. But as summer comes with higher temps the degradation probably is a bit higher.
I have quite much experience from using lithium batteries in other demanding applications, I will use this to try to keep the degradation low, but I will not make very big sacrifices, because this would take the fun out of having a M3 Performance and probably cause need to plan the life. I rather take a little more degradation than the minimum I could achieve.

You wont because degradation happens in chunks. For me it happened around 15k i think.
Noone here has a problem with degradation. We have a problem with excessive early degradation and misadvertisement by tesla.
Also you might not get the same degradationwe have. The mid 2019 australian cars are particularly and equally affected by severe degradation

 

[BrianBigNFun]

Not to mention there is a small buffer after it hits 0% that could be up to an extra 20 miles (as seen in the recent Edmunds test)

 

[AAKEE]

You wont because degradation happens in chunks. For me it happened around 15k i think.
Noone here has a problem with degradation. We have a problem with excessive early degradation and misadvertisement by tesla.
Also you might not get the same degradationwe have. The mid 2019 australian cars are particularly and equally affected by severe degradation

No, real degradation doesnt happen in chunks normally. If you have an constant environment and constant driving/charging habit the real degradation will be progressive, more in the beginning and then level of a bit.
If you had a year of DC charging, shallow cycles and then start supercharging and deep cycle you might experience a chunk.
Or the battery get ”preserved” in winter like up here an then we get hpt summer with the car outside in hot WX, you probably also get to see a quicker degradation. These kind of degradation is normal as these factors affect degradation/ aging.
I suspect chunks without external impact comes from BMS estimations or maybe software changes, causing the BMS to calculate it differently ?

I have seen no lithium battery tests showing degradation in chunks. For the some 100 lithium battery packs Ive used in other applikations I have only seen successive linear degradation, until they actually loose it and need to be replaced.

 

[AAKEE]

We have a problem with excessive early degradation and misadvertisement by tesla.

What is the excessive early degradation ?

Excessive should mean, it will not hold 70% at the guaranteed mileage, at the day it passes the time or mileage limit.
And as we know the first 50000km takes the largest hit, it is still ok if the degradation is more than 1/3 of the guarantee limit.
Also, the estimated range on the screen is not the actual range, so you need to check the real battery capacity.

How is Tesla missadvertising the Model 3 ?

 

[bedoig]

I think there is anecdotal evidence that the BMS holds to a factory estimate for a period of time before presenting its own calibrated estimates of capacity. The real degradation is presumably gradual but it presents itself to the user as a major drop off at a certain point. Mine also fell off around 15k miles (and kept going... and going...). In reality I think my pack left the factory with closer to 280-290 rated mile capacity in the first place.

 

[Carl_P]

If you had a year of DC charging, shallow cycles and then start supercharging and deep cycle you might experience a chunk.

This is what's currently happening to my mid-range. Can you explain a little more about why the "chunks" show up once you start supercharging? Here's my experience. I started supercharging more at the 15k mile point and you can see what happened. I'm at 10% range loss in 22k miles:

 

[AlanSubie4Life]

I think there is anecdotal evidence that the BMS holds to a factory estimate for a period of time before presenting its own calibrated estimates of capacity. The real degradation is presumably gradual but it presents itself to the user as a major drop off at a certain point. Mine also fell off around 15k miles (and kept going... and going...). In reality I think my pack left the factory with closer to 280-290 rated mile capacity in the first place.

View attachment 649907

Another explanation for this (which has been documented for some vehicle years & models) is that there is a hard cap on the displayed rated miles and in fact you had more energy than 310 rated miles (maybe closer to the equivalent of 317 rated miles) when you purchased the vehicle.

For example, some limited evidence suggests that 2018/2019 vehicles had 77.8kWh of capacity or so (basically the same pack as 2019, 2020 vehicles, and full pack when new in SMT shows 77.8kWh when read back, and EPA test results show no increase in usable capacity when going from 2018 -> 2020), but only showed capacity loss once they dropped below 76kWh. (We know that's the case since 310rmi*245Wh/rmi = 76kWh).

Exactly how this hard cap is managed is a different topic (one way is not displaying fewer than 310 rated miles until it drops below 76kWh, the other is inflating the energy content of each rated mile and having them tick off right away when you start driving).

This topic is related to the discussion about how Model S displays capacity loss. The fact is that people don't pay very close attention to these details (or at least they don't publicize them here, except occasionally), and it's very important to document them early in the life of vehicles and present them here so there is better understanding about how this is handled by Tesla. I'm sure if you dig around these forums you can find various forms of documentation of how it actually behaves (based on pictures and statements from various owners over the past 3 years), but it's a bit of a research project.

 

[AlanSubie4Life]

small buffer after it hits 0%

4.5% of the nominal full capacity of the battery in question, for Model 3. (The size is therefore different for each individual vehicle, and changes over time.)

I suspect chunks without external impact comes from BMS estimations or maybe software changes, causing the BMS to calculate it differently ?

Yes my understanding is that it is CAC estimate updates that cause this behavior, which apparently can be triggered by software updates on occasion (at least, there is a correlation, causation is less clear).

Can you explain a little more about why the "chunks" show up once you start supercharging? Here's my experience.

Correlation is not causation. However, heating of the battery, etc. which occur while supercharging seem that they could easily result in different estimates when the CAC updates. Some people see increases in range when supercharging. Last time I supercharged my full charge estimate went up, for example. Correlated. Causative? No idea. There's certainly a possibility that fast charging could change capacity, but it can also change the estimate a bit. There are a lot of moving pieces! Did you rule out software version updates (no software updates during this time period)? It's hard to blame one thing. I'm not say it's not the supercharging, I'm just saying there are many factors.

 

[Phlier]

You wont because degradation happens in chunks

No, real degradation doesnt happen in chunks normally.

The real degradation is presumably gradual but it presents itself to the user as a major drop off at a certain point.

@AAKEE I think we're all in agreement that real degradation happens progressively, but it certainly does appear that the BMS presents it in chunks. Almost like a thermostat hitting a temperature trip point, if you get the gist of that analogy.

Another explanation for this (which has been documented for some vehicle years & models) is that there is a hard cap on the displayed rated miles and in fact you had more energy than 310 rated miles (maybe closer to the equivalent of 317 rated miles) when you purchased the vehicle.

That explanation exactly matches what I saw with my car when it was new. There are other possible explanations, of course, but IMO, you guys have this one nailed.

 

[MACH5FL]

Thank you for your feedback. You pretty much hit the nail on the head with your assumptions. I'm still waiting on a reply from Tesla to see what they have to say. In the mean time, I'll continue to monitor the drmi periodically. I typically just drive with the display set to percentage. Other than my slight battery degradation concern, the car has been great so far.

Thank you for your feedback. You pretty much hit the nail on the head with your assumptions. I'm still waiting on a reply from Tesla to see what they have to say. In the mean time, I'll continue to monitor the drmi periodically. I typically just drive with the display set to percentage. Other than my slight battery degradation concern, the car has been great so far.

Given it looks like you're doing mostly freeway driving with a lot of AC use, that's a pretty enviable result.

You have used 10.2MWh of energy to do your 38480 miles.

Your battery started with 47.5kWh capacity (supposed to be 48kWh). It's now at 41.6kWh (190rmi * 219Wh/rmi).

You've put 10200kWh/48kWh = 213 nominal cycles on your battery, not including regen which is probably fairly minimal in Florida with that sort of commute.

13% capacity loss with that many cycles, after about 18 months, seems ok. As many have discussed here, this may well be above the norm for Model S/X packs, but it seems very normal for Model 3 pack capacity loss. Tesla Service will tell you to take a hike, nicely. That's just the way it goes. Once you get to 154 rated miles (assuming you don't hit the mileage limit (of 100k?) first), you will have a claim.



This seems fine. Since you have charging at work this vehicle works for you, and it should work just fine. You should be able to make the 107-mile one way trip at 266Wh/mi while using about 107mi*266Wh/mi/0.99 / (0.955rmi/drmi*219Wh/rmi) = 137 displayed rated miles (drmi). For your current 190-mile capacity battery that's going to be 72% of your SoC, so if you leave at 93% you're probably arriving at home at around 20% SoC. Just roughly. Obviously YMMV, literally, due to conditions like wind, rain, elevation change, etc. But this is for an actual displayed trip efficiency of 266Wh/mi (I'm using your lifetime average and assuming that's about what you get when driving your commute).

Given it looks like you're doing mostly freeway driving with a lot of AC use, that's a pretty enviable result.

You have used 10.2MWh of energy to do your 38480 miles.

Your battery started with 47.5kWh capacity (supposed to be 48kWh). It's now at 41.6kWh (190rmi * 219Wh/rmi).

You've put 10200kWh/48kWh = 213 nominal cycles on your battery, not including regen which is probably fairly minimal in Florida with that sort of commute.

13% capacity loss with that many cycles, after about 18 months, seems ok. As many have discussed here, this may well be above the norm for Model S/X packs, but it seems very normal for Model 3 pack capacity loss. Tesla Service will tell you to take a hike, nicely. That's just the way it goes. Once you get to 154 rated miles (assuming you don't hit the mileage limit (of 100k?) first), you will have a claim.



This seems fine. Since you have charging at work this vehicle works for you, and it should work just fine. You should be able to make the 107-mile one way trip at 266Wh/mi while using about 107mi*266Wh/mi/0.99 / (0.955rmi/drmi*219Wh/rmi) = 137 displayed rated miles (drmi). For your current 190-mile capacity battery that's going to be 72% of your SoC, so if you leave at 93% you're probably arriving at home at around 20% SoC. Just roughly. Obviously YMMV, literally, due to conditions like wind, rain, elevation change, etc. But this is for an actual displayed trip efficiency of 266Wh/mi (I'm using your lifetime average and assuming that's about what you get when driving your commute).

Tesla service reached out to me this morning. They said my battery was fine. But, did mention it’s an outlier from the fleet average. It got interesting when I started to ask more detailed questions. The more questions I asked, the more I felt the Tesla service rep was not well versed on matters concerning battery degradation, the meaning behind the drmi, etc. The rep had to go fetch more information and call me back. On the call back, he says my battery has degraded 20.3%. This figure is more than what the drmi infers. By the way, at 100% SOC, my drmi is now at 188 miles. I asked the rep to call me back later today to further discuss the 20.3% degradation. I’m not liking where this trend is heading.

 

[Phlier]

On the call back

I'm just impressed that you got the call back.