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

[tm1v2]

The reported range you're looking at is NOT adjusted for weather or driving style or anything else. It's just battery SoC multiplied by EPA rated efficiency. And as @UncertainTimes said, battery SoC is really an estimation, there is some margin for error.

My 265 mile EPA rated S P85 used to report 268 miles at 100% charge when it was newer. I think I charged my 2021 M3P to 100% once but I already forgot what it reported. Nothing alarming I guess.

 

[UncertainTimes]

Change your displayed battery to percentage. You’ll always have 100%

 

[AAKEE]

Hello,

I have about 1200 miles on my 2022 Model 3 Performance and have noticed that my range shows 316 miles compared to the 315 as advertised in the ongoing weeks. Of course, this is a minor increase, but I was curious why it's higher than it should be, especially with it being extremely cold where I'm located.

Is this when actually having charged full looking at the display of the car ?
The range seen in the app is not that precise, so it can not be used as a complete truth.

If the battery hace an nominal capacity of about 81.4kWh or more, the screen showed 509 km (316mi) at full charge for me. This seem to be the max range that can be shown as it still showed 509km despite having 82.0 kWh nominal remaining(actual energy stored).

So it seems like your battery is fine with good capacity. How is your charging schedule, what SOC do you charge to?

The software change that @FlatSix911 refers to is about the energy screen and navigation calculations.
The range on the screen at the battery is calculated from pure battery energy.
Each km is 159 Wh( Each Mile is 256Wh).

I live at the artic circle in a very cold climate, the winter with -30C do not change the on screen range to a lower value.

 

[beenmb]

About charging our Model 3 Long Range. We can plug in every night using a regular wall outlet (here in the U.S.). We can get enough charge for the next day's driving adjusting the car's charging down to drawing 8A or 10A rather than 12A. Is that ok? Is that good or bad for the battery pack long term? We want to own and enjoy this car for many, many years. Appreciate your advice. Thanks, Brian

 

[jjrandorin]

About charging our Model 3 Long Range. We can plug in every night using a regular wall outlet (here in the U.S.). We can get enough charge for the next day's driving adjusting the car's charging down to drawing 8A or 10A rather than 12A. Is that ok? Is that good or bad for the battery pack long term? We want to own and enjoy this car for many, many years. Appreciate your advice. Thanks, Brian

There is absolutely zero reason (for the car) to change the amps from 12a to 10a or 8a (none). ALL home charging (including 240v 48amp) is "slow" to the car. All you are doing on the car side is keeping the car awake longer because it doesnt sleep when its charging. Keeping the car awake longer = more power used in general, because there is overhead for energy use for the car being awake.

TL ; DR -- It wont matter to the car at all, but there isnt any reason on the CAR side to do this at all, because you are just keeping the car awake longer and wasting energy. If you have a reason to do this because its not a dedicated circuit or something thats one thing. For the CAR? no reason at all to turn it down.

 

[FlatSix911]

The reported range you're looking at is NOT adjusted for weather or driving style or anything else. It's just battery SoC multiplied by EPA rated efficiency. And as @UncertainTimes said, battery SoC is really an estimation, there is some margin for error.

My 265 mile EPA rated S P85 used to report 268 miles at 100% charge when it was newer. I think I charged my 2021 M3P to 100% once but I already forgot what it reported. Nothing alarming I guess.

If you use the trip function for range, it will now include accounting for crosswinds and headwinds,
air density, and humidity in the energy consumption calculation when the data is available.

Tesla is starting to account for wind, air density, and more when doing range calculation

Tesla is now starting to account for wind, air density, and more when doing range calculations in an attempt to...

electrek.co

 

[MP3Mike]

If you use the trip function for range, it will now include accounting for crosswinds and headwinds, air density, and humidity in the energy consumption calculation when the data is available.

Of course you left out the important part: where data available, maybe only in China at this time.

 

[SillyPosition]

First of all, again, following Teslas very advices will be fine. But most probable it is possible to reduce the degradation from that.
Charging habits:
The lower the SOC, the less is the wear.
This is true for both calendar aging and cyclic aging so the best charging level is the lowest SOC that you can use.
The steep step at about 55-60% which means reducing the calendar aging to the half is probably the thing one need to know.
If you have the choise of selecting 55% instead of 60%, the degradation will be clearly less.
My 55% selection is made from that. Even though 50% cause slightly less degradation 55% give me a little bit extra SOC at more or less no cost.
I charge before the drive during weekdays so it stands at work with about 40% and when home again at 20-30% depending on the time of the year.
During weekends 55% gice me a fair range if a unplanned trip is made. I havecthe car set to charge to 55% each night so sone weekends(quite feew) it stands all weekend with 55%. It would be possible to lesve the car with 20-30% over the weekend but then I would need to charge before a pleasure trip etc. Not worth the small gain.

I did get a M3P for the power and I use the power quite often. I dont get full power at 55% but I can live with this, and when I need I charge to a higher SOC, for fun.
For the battery longevity, small/shorts bursts of 10-15s or so will not have a very bad effect on battery life.
Lithium batteries for my hobby is often specified with maximum continous current and also bursts of 10-20s with much higher currents allowed during this period.
You can use the power for these shorter burst without killing thr battery.

If you need more power and charge to a higher SOC charge shortly before the drive, there will be no increased calendar aging as you do not leave it with higher SOC.
The higher SOC cause a cycle with slightly more cyclic aging, but as cyclic aging often is the much smaller part it is so small that it will not be possible to detect the difference.

So your choice for 55% is only to act as a buffer for unplanned trips during the week? Since you said you need about 30% for your daily commute.
If you wouldn't want to handle unplanned commute, would charging to 35% and arriving home almost drained completely (hypothetically, 5% isn't that much and in real life..flactuations in traffic can alone eat that 5%), be even better?
I know that tomorrow I will need 30% for my commute. Im now with 44%. I can either fill it up to 50-55%, and arrive home at the end of the day with 20-25%, or simply not charge at all and arrive with ~15%.

Regarding calendar aging, given that I already have the car for a year, and I caused a calendar aging of about 5-6%,
and given that its often considered to be, in some wise man words:

Calendar aging is worst in the begining but lessens with (about) the square root of time. If first year causes 5% you will not reach 10% until four years( square root of four = 2 —> doubled the first years aging after four years).

So isnt it sort of "the harm is done", and from this point onwards, charging daily to 55%, or charging it to 80% as I normally did thus far, would it even make a noticeable different at this point?
Per the formula Im expected to 10% degredation by the end of the third year?

 

[AAKEE]

So your choice for 55% is only to act as a buffer for unplanned trips during the week? Since you said you need about 30% for your daily commute.
If you wouldn't want to handle unplanned commute, would charging to 35% and arriving home almost drained completely (hypothetically, 5% isn't that much and in real life..flactuations in traffic can alone eat that 5%), be even better?
I know that tomorrow I will need 30% for my commute. Im now with 44%. I can either fill it up to 50-55%, and arrive home at the end of the day with 20-25%, or simply not charge at all and arrive with ~15%.

I could use 50%, there is no choise to charge to a lower value( its possible by setting the charging to commence so that it reaches only 35% when you are about to leave.) But, I still will have quite low degradation. My decision when I got the car was to use my knowledge to minimize the degradation without sacrificicing the fun, and also to not to limit my self to the level where I need to use the ICE car due to too low SOC.
It would be possible to reduce the degradation slightly more but it would not be fun. I also do some things like doing a full charge just to test it, or to see the capacirty etc that cause some extra degradation(not much but still a little) that is only nerd things and not needed.

Regarding calendar aging, given that I already have the car for a year, and I caused a calendar aging of about 5-6%,
and given that its often considered to be, in some wise man words:

So isnt it sort of "the harm is done", and from this point onwards, charging daily to 55%, or charging it to 80% as I normally did thus far, would it even make a noticeable different at this point?
Per the formula Im expected to 10% degredation by the end of the third year?

No, the actual lost capacity is lost(wont come back). But if you start reducing the loss you will have a reduced degradation.
5-6% after one year is probably about 5% calendar aging and about 0.5-1% cyclic or so. The easiest way would be to calculate all as calendar aging and then it is 5 or 6% x square root of 3 = about 10%.
(The formally correct way would be 5 x square root of 5 + 3 x the cyclic ( = 3x 0,5). Not thast it makes an big difference for this example but if one would like to calc for longer times, it will)

 

[Candleflame]

The reported range you're looking at is NOT adjusted for weather or driving style or anything else. It's just battery SoC multiplied by EPA rated efficiency. And as @UncertainTimes said, battery SoC is really an estimation, there is some margin for error.

My 265 mile EPA rated S P85 used to report 268 miles at 100% charge when it was newer. I think I charged my 2021 M3P to 100% once but I already forgot what it reported. Nothing alarming I guess.

its insane that the whole driving style rumour is still floating around after 10 years of Model S/X/3....

 

[Steve446]

its insane that the whole driving style rumour is still floating around after 10 years of Model S/X/3....

My aim is not to criticize but don't you think that there is some truth in the driving style comment? Does it also depend on the EV and battery type and design? I like having fun too but, for example, I noticed that standing starts at busy roundabouts really impact the range of my Renault Zoé (it's got good torque up to 60 Km/h), but that takes a Km or so off the range each time I do it. In contrast there seems to be no impact when I do that with my M3 or is that just related to a larger battery size and discharge capability making that less noticeable?

 

[hgmichna]

I have a very specific question about the LFP battery in the newer Made-in-China Model 3 RWD, to which I could not find any answer so far.

Assuming I want to drive my car for 20 years and 300,000 miles with its original LFP battery and assuming that the car is being slow-charged whenever it is parked: what is a near-optimal, good compromise setting for the charging target? 100%? 90%? 80%? Even less?

We already know some things fairly certainly. We know that you can leave the setting at 100%—Tesla even recommends it—if you are aiming for a normal lifetime of the car, like 10 years and 150,000 miles. We also know that LFP batteries and their Battery Managemen System needs 100% from time to time, like once a week or once before every long drive. We also know from scientific analysis that LFP batteries survive 5,000 and more full cycles, i.e. millions of miles, if not stressed by high voltages, high currents, and high temperatures. However, such cycling tests touch 100% only for very short times.

What we do not know is how they degrade when kept at 100% for extended times. I could not find any scientific data about this particular situation. Nobody seems to have tested this.

Some people have speculated that the degradation depends mainly on the voltage. Since LFP batteries have a stable middle voltage until going above 90%, they speculate that keeping them at 90% would do no harm and would be very similar to keeping them at 50%. However, this is just conjecture, not proven truth. Obviously other things beside voltage change inside the cells with their state of charge, and those things can have an effect on longevity. So this line of thinking may be right or may be wrong, we just don't know.

Has anybody found any answer to this very specific question anywhere? No guessing, please. That I can do myself.

 

[tm1v2]

@hgmichna Everything official I've read says 100% charge is good for the LFP packs. The more time they spend at 100% the better. With LFP I would keep my charge target at 100% and not overthink it.

As far as I know the only reason LFP cars even support lower than 100% charge target is for circumstances like one-off charging on a very expensive charger and wanting to minimize use of it.

 

[Candleflame]

My aim is not to criticize but don't you think that there is some truth in the driving style comment? Does it also depend on the EV and battery type and design? I like having fun too but, for example, I noticed that standing starts at busy roundabouts really impact the range of my Renault Zoé (it's got good torque up to 60 Km/h), but that takes a Km or so off the range each time I do it. In contrast there seems to be no impact when I do that with my M3 or is that just related to a larger battery size and discharge capability making that less noticeable?

No truth at all.
Rated Range is a unit of energy NOT a distance measurement. The number could actually just show the amount of kwh in the battery left. The number will vary a bit at any given % as the BMS doesnt always estimate the kwh in the battery accurately.
Its really hard for people new to Tesla to get their head around this.

 

[Steve446]

No truth at all.
Rated Range is a unit of energy NOT a distance measurement. The number could actually just show the amount of kwh in the battery left. The number will vary a bit at any given % as the BMS doesnt always estimate the kwh in the battery accurately.
Its really hard for people new to Tesla to get their head around this.

Fair comment and I agree. I guess that my remark wasn't very clear! To rephrase, for me, for a specific drive, the real world range of the car, calculated from the measured available kWh in the battery can, amongst other influences, be impacted by a persons driving style whether standing starts, rural speeds or motorway speeds. Personally, I would certainly like to see the range display changed to a kWh left value - more meaningful for me, but then I'm a geek and, probably most people can't be bothered with that!

 

[hgmichna]

@hgmichna Everything official I've read says 100% charge is good for the LFP packs. The more time they spend at 100% the better. With LFP I would keep my charge target at 100% and not overthink it.

As far as I know the only reason LFP cars even support lower than 100% charge target is for circumstances like one-off charging on a very expensive charger and wanting to minimize use of it.

Thanks. Where exactly do you know this from? Do you have a link or two?

 

[tm1v2]

Thanks. Where exactly do you know this from? Do you have a link or two?

@hgmichna Check your local Tesla Model 3 Owner's Manual. Here's what Tesla recommends in the US, and I don't see why it would be different elsewhere.

Model 3 Owner's Manual | Tesla

Learn how to charge your vehicle and use scheduled charging features.

www.tesla.com

Note
If your vehicle is equipped with an LFP Battery, Tesla recommends that you keep your charge limit to 100%, even for daily use, and that you also fully charge your vehicle to 100% at least once per week. See Lithium Iron Phosphate Batteries.

Model 3 Owner's Manual | Tesla

Learn about your vehicle’s battery and battery best practices.

www.tesla.com

Lithium Iron Phosphate Batteries​

Some vehicles are equipped with a Lithium Iron Phosphate (LFP) Battery. To determine if your vehicle has a LFP Battery, open the charging screen on your touchscreen and then touch Set Limit, or open the charging screen in your mobile app and drag the slider.

• If the image of the Battery displays "50%" and "100%" then your vehicle is equipped with a LFP Battery.
• If the image of the Battery displays "Daily" and "Trip" then your vehicle is NOT equipped with a LFP Battery. Disregard this section.

If your vehicle is equipped with an LFP Battery, Tesla recommends that you keep your charge limit set to 100%, even for daily use, and that you also fully charge to 100% at least once per week. If Model 3 has been parked for longer than a week, Tesla recommends driving as you normally would and charge to 100% at your earliest convenience.

It seems clear and unambiguous to me - always charge LFP to 100% when practical. If circumstances sometimes don't allow it, don't sweat it, but for normal daily charging at home let it fill up to 100%.

 

[AAKEE]

@hgmichna Everything official I've read says 100% charge is good for the LFP packs. The more time they spend at 100% the better. With LFP I would keep my charge target at 100% and not overthink it.

As far as I know the only reason LFP cars even support lower than 100% charge target is for circumstances like one-off charging on a very expensive charger and wanting to minimize use of it.

There is no research data that support the theory that 100% SOC is better for the battery life.
Teslas advice is most probably related to efforts to keep the BMS on ttack with the actual SOC.
The flat voltage curve make it hard for a BMS to know the SOC from voltage only.

 

[tm1v2]

There is no research data that support the theory that 100% SOC is better for the battery life.
Teslas advice is most probably related to efforts to keep the BMS on ttack with the actual SOC.
The flat voltage curve make it hard for a BMS to know the SOC from voltage only.

If you're looking for a real-world study of well aged, high-mileage Tesla LFP battery pack performance...you're going to be waiting a while.

Have you found anything to suggest charging less than 100% is better for the LFP packs?

 

[Magimbe]

Hello everyone,

I bought a used (Tesla inventory) 2019 Tesla Model 3 Performance a few days ago, the car is in good shape and looks new. The only "strange" thing I found until now is the discrepancy between range and charge. I am charging in our condo SEMA chargers, and if I try to charge at 100% the range proposed is 278 miles instead of 312 miles. I asked the question to Tesla support chat they had run a remote control of my battery and they told me everything is fine and a slight degradation is normal but the car has 27000 miles. Do I need to worry?

Thanks