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

[GrandLakeS]

I get 66-75% real miles to “battery miles” depending on a host of factors, already noted in this string of comments. Would be nice to know this when one is sold the car. Our S and Y are similar in this outcome.

 

[AAKEE]

Thats what ive been saying. Battery care is almost irrelevant when the main factor is battery lottery.

But going up to 90% and leave it at that SOC isnt the best battery care if you ask me.

Tesla of course use the biggest window of SOC that both gives the owner a the largest window of carefree owning and still keep the degradation on a acceptable level for not risking the 70% within the warranty period.

 

[Candleflame]

But going up to 90% and leave it at that SOC isnt the best battery care if you ask me.

Tesla of course use the biggest window of SOC that both gives the owner a the largest window of carefree owning and still keep the degradation on a acceptable level for not risking the 70% within the warranty period.

Yes we all know whats good for the battery. But not how bad i.e. Leaving it at 100% actually it.

 

[AAKEE]

Yes we all know whats good for the battery. But not how bad i.e. Leaving it at 100% actually it.

If you leave it at 90-100% for the most days, it probably degrades more than 5% for the first year at 25C temperature. This for the storage only, without driving.

Low SOC is better and small DOD’s is better.
If you perform actions very often to keep the Rated range high by leaving the car at high SOC, youre hurting the battery with unnessesary degradation, just to (maybe) se a higher rated range( the true range doesnt really change, except for going down a little faster due to increased degradation.


I do not think it is pure luck that I still have full range after 10 monts/25000km.

 

[Candleflame]

If you leave it at 90-100% for the most days, it probably degrades more than 5% for the first year at 25C temperature. This for the storage only, without driving.

Low SOC is better and small DOD’s is better.
If you perform actions very often to keep the Rated range high by leaving the car at high SOC, youre hurting the battery with unnessesary degradation, just to (maybe) se a higher rated range( the true range doesnt really change, except for going down a little faster due to increased degradation.


I do not think it is pure luck that I still have full range after 10 monts/25000km.

yes, all these are valid points but it doesnt change the fact that many people deep discharge their batteries all the time and many fleet vehicles to 100% to 0% discharges all the time - and yet only have afew % degradation. And many people who pamper their battery have 15% degradation.

Low SOCs etc are INSIGNIFICANT compared to the battery lottery.

And yes it is pure luck that you have full range after 25k kms.

 

[AAKEE]

yes, all these are valid points but it doesnt change the fact that many people deep discharge their batteries all the time and many fleet vehicles to 100% to 0% discharges all the time - and yet only have afew % degradation. And many people who pamper their battery have 15% degradation.

Low SOCs etc are INSIGNIFICANT compared to the battery lottery.

And yes it is pure luck that you have full range after 25k kms.

I do not think that it is possible for Tesla or the coincidence to circumnavigate the physics shown in lot of research with the same or very similar NCA-cells.

There might be a battery lottery as you say but if so, the proved physics of degradation add on to the lottery.
I can not see it in any other way.
You can not store Panasonic NCA cells att high SOC and not have any degradation from this. The same for high SOC plus high ambient temps, it have to show in degradation.

 

[Widdizzles]

My 2021 model 3 LR is brand new, I’ve only driven 400 miles over the last few days and have had to charge my battery 3 times. A total of 60 dollars… wtf. Im using best practices and only operating the battery from 20-90 percent. My battery drains 5-10% over night

 

[bjrosen]

Turn off Sentry Mode when you are at home, there is a switch for this. Sentry Mode keeps the car from sleeping and raises the vampire drain immensely. WIth Sentry Mode off you should expect the drain to drop to 1%.
One more tip, set the maximum to 80%, use 90% for road trips.

 

[Jeremy3292]

My 2021 model 3 LR is brand new, I’ve only driven 400 miles over the last few days and have had to charge my battery 3 times. A total of 60 dollars… wtf. Im using best practices and only operating the battery from 20-90 percent. My battery drains 5-10% over night

There is no reason your battery should drain 5-10% overnight. Mine sits my garage all night and doesn't even lose 1%. Do you have sentry mode on or some climate controls on overnight?

Also not sure how you got to $60 for 400 miles...that's way more than even superchargers cost.

 

[Widdizzles]

I have SS to prove my claims, it’s actually a little over $50 and my app reflects that I’ve only driven 400 miles. .29 per KWh where I’m at.

 

[Widdizzles]

There is no reason your battery should drain 5-10% overnight. Mine sits my garage all night and doesn't even lose 1%. Do you have sentry mode on or some climate controls on overnight?

Also not sure how you got to $60 for 400 miles...that's way more than even superchargers cost.

And I do have sentry mode on, but does that really justify 5 percent loss over 10hrs? That’s 15-20 miles

 

[jjrandorin]

And I do have sentry mode on, but does that really justify 5 percent loss over 10hrs? That’s 15-20 miles

Yes, absolutely positively 1000% yes. Sentry mode uses 1-2 miles an HOUR of usage. Over 10 hours, that will be 10-20 miles. You may have only "driven" over 400 miles, but if you have sentry mode on every night you are using an additional 10-20 miles a night that your battery is driving, even if you arent.

 

[Jeremy3292]

I have SS to prove my claims, it’s actually a little over $50 and my app reflects that I’ve only driven 400 miles. .29 per KWh where I’m at.

I wasn't suggesting you were lying, that just seems high. Wasn't aware you were using SC exclusively either, which also isn't recommended and costs way more than an L2 charger. 82 kWh battery pack at $0.29 per kWh = $23.78 per "tank" or 0% to 100% at a SC (not sure of charger inefficiencies).

And I do have sentry mode on, but does that really justify 5 percent loss over 10hrs? That’s 15-20 miles

Yes, absolutely. I only use sentry mode when I'm plugged in (like at work) or if it's somewhere quick(ish) like a grocery store or restaurant. I park in a garage at my house at night so no need for sentry mode. If you have to park outside, can you at least be plugged in and charging so sentry mode doesn't drain your battery all night and pulls power from the charger instead?

 

[jjrandorin]

My 2021 model 3 LR is brand new, I’ve only driven 400 miles over the last few days and have had to charge my battery 3 times. A total of 60 dollars… wtf. Im using best practices and only operating the battery from 20-90 percent. My battery drains 5-10% over night

I made a post in the model Y subforum but its relevant here. The thread is this one:

Battery decreased about 20 miles overnight

Parked my car in the street after fully charged and next morning when I check the app, it went down 20 miles, and another 10 miles around 2pm. I understand that turn on sentry mode will cost some miles but to this much? I got my car on 9/9 so it is pretty new still. anyone have similar situations?

teslamotorsclub.com

Same topic.... member confused about the amount of drain overnight (which only really concerns people when they are not charging at home). The relevant post is this one I am about to post in here, but the TL ; DR version is, Its my belief that the SINGLE BIGGEST MISTAKE owners or potential owners of these vehicles without home charging make is some variation of "Oh this car has a 320 mile range, I only drive 20 miles a day, I can charge every 10 days at a supercharger and have plenty left over"

===================================

This is one of the biggest mistakes potential tesla owners make, in my personal opinion. I personally am not a huge fan of owning one of these cars without either home or work charging (as in, charging where you live, or spend 8 hours working at).

People without home or work charging tend to think some variation of " Oh, I am buying a car with 300 miles range, I only drive 20 miles a day, so I should be able to charge every 10 days or so and have some spare left over" and it absolutely, positively does...no...work at all like that.

Lets use a model Y that has "326 Miles EPA range". EPA range bolded for a reason.

No one is going to drive from 100-0. Its recommended to charge on a regular basis to no more than 90%, and most people are not going to go much below 20% on an EV.

90% of 326 is 293.4 (lets call it 294)
20% of 326 is 65.2 (lets call it 66)

So, right off the bat, a "326 EPA range" model Y has an actual effective range of 294-66, or 228 miles of range.

This does not take into account that the EPA range can only be achieved if one drives like the EPA tests (just like a gas vehicle). On average, if a commute above is 20 real world miles, that commute will take between 20 and 35 miles off the range meter, depending on weather, speed driven, etc.

None of this takes into account energy used while not driving, like sentry mode, or taking lunch in your car and watching netflix or disney plus, etc etc

So the above fictional person, who has a 20 mile commute but no home charging, and who expects "Oh my tesla goes 326 miles, my commute is only 20 miles a day, so 10 days of usage should be 200 miles, so this will be a piece of cake", is in for a rude awaking.

What will actually happen for this person is their 20 mile commute will likely use 30 miles of range on average, and they dont have "326 milees" they have 228 miles, or 7 days ish before their car is at 20% or lower.

Its also VERY common for someone who doesnt have home charging to also want to use sentry mode (because if they had a garage they likely could plug in at home), so there goes another 12-20 miles a night of usage they were not expecting. Call that, conservatively, 15 miles a night, and now the car is using 30 miles driving + 15 miles a night, or 45 miles a day, for a "I need to refill the battery" time of 5 days, when they were expecting on a conservative basis to do it every 10 days and have plenty left over.

Change the math for whatever your actual commute is. If you were expecting 7 days, its probably more like 3.

When I see people ask in the model 3 subform "should I buy this car if I dont have home charging" I usually say "only if you have some reason other than convenience for buying the car".

Home charging (or work) changes all of that, because it simply doesnt matter how much power you use then, because you dont go anywhere to "fill up". That 20 miles a day driven uses 30 miles a day, but so what, its not even noticed.

I am just laying out the "real world" usage for "not charging at home", and how many miles people use. This is not a "tesla" issue, really, its an "EPA range" issue and the fact that people look at the miles and forget that they are not going from 100-0.

 

[LastGas]

I'm trying to figure out the difference between bad and broken on my 2018 Model 3 LR RWD battery.

The EPA mileage on my car is 310 miles, but not long after I got it, Tesla sent out a firmware update saying that the mileage had increased to 325. When the car was new, it did charge to 310, but soon afterwards that number was never approached again.

Three years later, after about 25,000 miles, the car's best charge is 286 miles. If the base is 325, then degradation is 12%. If 310 is the base, then degradation is is about 8%.

What concerns me more is the results from Scan My Tesla. It shows the "Full pack when new" value is 77.8 kWh and now the "Numinal full pack" is 67 kWh or about 14% loss.

I don't normally charge over 80% and my DC charge total is about 22% of total charges.

My degradation isn't enough to trigger a warranty claim, but it's far more than what I see from other M3 drivers. Insights and suggestions welcome.

 

[AlanSubie4Life]

Tesla sent out a firmware update saying that the mileage had increased to 325

the car's best charge is 286 miles. If the base is 325, then degradation is 12%. If 310 is the base, then degradation is is about 8%.

It shows the "Full pack when new" value is 77.8 kWh and now the "Numinal full pack" is 67 kWh or about 14% loss.

The LR RWD has a constant of 234Wh/rmi (and always has - the 310->325 unlock unlocked capacity AFAIK). SMT says FPWN of 77.8kWh. It's possible that your early vehicle never quite had this capacity (though some vehicles probably did). That works out to 77.8kWh/234Wh/rmi = 332 rated miles. However, the degradation threshold (where degradation starts to show) is 76kWh. That works out to 76kWh/234Wh/rmi = 325rmi. Basically the display was limited to 325 rated miles, even if you started with the equivalent of 332, in energy terms.

So, SMT is correct; you have about 13.9% loss. However, to be clear, we don't know exactly where your pack started (that value SMT reports is a hard-coded value associated with the pack and does not reflect exactly where your particular vehicle started).

It's possible you have actually lost as little as 12% if you actually started closer to 76kWh. (The only way you'd know this is if you had SMT right at the beginning.)

I think it is likely your pack started around 77-78kWh. But the data on those early packs early in their life is very sparse, so there's really no way to know for sure.

14% loss after 3 years and 25k miles seems pretty normal, but possibly slightly on the high side. It's actually a pretty great result. My 2016 Chevy Spark has lost about 35-40% capacity at about 24k miles (equivalent to about 75k on the Tesla I suppose) as mentioned earlier here. The plus side is it has not caught on fire spontaneously.

 

[Candleflame]

I'm trying to figure out the difference between bad and broken on my 2018 Model 3 LR RWD battery.

The EPA mileage on my car is 310 miles, but not long after I got it, Tesla sent out a firmware update saying that the mileage had increased to 325. When the car was new, it did charge to 310, but soon afterwards that number was never approached again.

Three years later, after about 25,000 miles, the car's best charge is 286 miles. If the base is 325, then degradation is 12%. If 310 is the base, then degradation is is about 8%.

What concerns me more is the results from Scan My Tesla. It shows the "Full pack when new" value is 77.8 kWh and now the "Numinal full pack" is 67 kWh or about 14% loss.

I don't normally charge over 80% and my DC charge total is about 22% of total charges.

My degradation isn't enough to trigger a warranty claim, but it's far more than what I see from other M3 drivers. Insights and suggestions welcome.

thats roughly what i have so pretty normal unfortunately. and you have an older car. (We know model 3 degrades heavily with time as opposed to kms)

 

[Timspeed]

@jjrandorin
damm that’s a wake up call! But you explained it dead on!
for a 2021 LR 3
for daily use, Tesla recommends keeping it between 80%-20%..thats 211 “EPA” miles!
real world more like 185!
that’s crazy! In my ICE car, Id regularly let it get down to 10% fuel left (1-2 gallons in a 12.8 gallon tank), and it’d get me 300 miles with that 90%
I guess it doesn’t matter because “road tripping”, you can go 100%-10%, which will get it cloooose to 300 miles, optimally.

 

[jjrandorin]

@jjrandorin
damm that’s a wake up call! But you explained it dead on!
for a 2021 LR 3
for daily use, Tesla recommends keeping it between 80%-20%..thats 211 “EPA” miles!
real world more like 185!
that’s crazy! In my ICE car, Id regularly let it get down to 10% fuel left (1-2 gallons in a 12.8 gallon tank), and it’d get me 300 miles with that 90%
I guess it doesn’t matter because “road tripping”, you can go 100%-10%, which will get it cloooose to 300 miles, optimally.

Actually, no, tesla does not "recommend keeping it between 20% and 80%. That is no where in any official tesla information. They recommend charging a model 3 anywhere in the "daily" section (for non LFP model 3s) and that is from 50% to 90%. You will not find anything from tesla that says "charge to 80%, thats internet forums. The fact that you are quoting that, tells me that you too have "gone down the battery rabbit hole" (lol).

 

[Candleflame]

Actually, no, tesla does not "recommend keeping it between 20% and 80%. That is no where in any official tesla information. They recommend charging a model 3 anywhere in the "daily" section (for non LFP model 3s) and that is from 50% to 90%. You will not find anything from tesla that says "charge to 80%, thats internet forums. The fact that you are quoting that, tells me that you too have "gone down the battery rabbit hole" (lol).

elon musk recommended 90% to 20%. 80% for best longevity and anything below not worth it. He also stated to not be afraid to discharge the car to 5% or lower.