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

[PhysicsGuy]

Hi. Totally new to this forum, and to forum-posting in general. I sort of searched for this topic, but didn't find anything on here on this question specifically I have a question about charging.

I've had my Model 3 Long Range since September 2018. Pre-Covid, I did 95% of my charging at work, so I stuck to the 20% Min / 80% Max rule almost all the time.

Now, in Covid-world, I work from home, so I have to charge at home. I have a 220 outlet, but because of logistics, it's a bit inconvenient to use. SO, there are times that I want to get more range than the 20/80 allows for.

My question is this - am I being better to my battery by charging to 95%, then taking it no lower than approximately 20%, or would it be more beneficial to the long-term battery life if I charge to only 80%, but take the car down to 5 to 8 % ?

For argument's sake, lets say that I -have- to do this three to four times per month.

Again - please forgive me if I posted in the wrong place.

Thanks !

95% to 20% is better for your battery than 80% to 5%. It would be preferable not to let it sit at 95% though.

 

[PhysicsGuy]

Thanks, so when @PhysicsGuy wrote “never touch the shore” does that mean don’t hit 0% SoC?

What about “manipulate your state of charge in any way”, how could we even do that?

By manipulation I mean anything that you do with the express purpose of getting your state of charge, as expressed in miles, to exhibit a higher number. That includes touching the shore, or any deliberate cycling from very high to very low SoC.

 

[MarcG]

By manipulation I mean anything that you do with the express purpose of getting your state of charge, as expressed in miles, to exhibit a higher number. That includes touching the shore, or any deliberate cycling from very high to very low SoC.

When I do long trips that includes multiple supercharging sessions, I typically start at a high SoC (over 90%) and drive continuously for over 2 hours, sometimes 3, until I hit my first supercharger stop. This might drop the SoC to under 5%. Are you saying this is bad, even if it's only once every several months? (My normal charging pattern at home is to plug in before I hit 25% and only charge to 80%, which is about once a week these days).

 

[PhysicsGuy]

When I do long trips that includes multiple supercharging sessions, I typically start at a high SoC (over 90%) and drive continuously for over 2 hours, sometimes 3, until I hit my first supercharger stop. This might drop the SoC to under 5%. Are you saying this is bad, even if it's only once every several months? (My normal charging pattern at home is to plug in before I hit 25% and only charge to 80%, which is about once a week these days).

I would not personally plan to go that low. I would do an extra stop and just supercharge for like 10 minutes to avoid 5%, but I don't think what you are doing is unreasonable and, really, it is probably totally fine. I mean you are actually going somewhere and that is what the car is designed for.

 

[PhysicsGuy]

(My normal charging pattern at home is to plug in before I hit 25% and only charge to 80%, which is about once a week these days).

That is a great charging pattern.

 

[MarcG]

Yeah, I figured I was doing it mostly right given my range at almost 20,000 miles on the odometer is in the 90% percentile.

 

[tony34]

i bought my model 3 in aug 2018. After the software upgrade I only got 316 miles when charged to 100%. Last night I got only 312 miles from 5% SOC to 100%. A 4% degradation within 10 months? Have others degraded similarly?

Yeah. Update in Oct 2019 dropped my range ~5%.

 

[Plombir]

Such a big loss... I tried recalibrate but it didn't help. Does it make sense to create ticket in technical support? Or there's nothing I can do until range drops to 30%?View attachment 561905

So i created a ticket and sent this chart. That is response i got:

With your vehicles mileage and age this would be considered normal battery degradation. Please keep in mind that there are over 800,000 Model 3's in our data base, so when we do a battery health check our system goes off of that data. From the looks of it the degradation app you are using only is only comparing your car to 113 other vehicles.

Every car is different. It all depends on your driving and charging habits. But usually anywhere from 10% is normal for the first year.

 

[Rawlings2019]

Okay so after 17,000 miles and right about 14 months of ownership my model 3 lr rwd shows 100% as 294 miles. It used to show it as 318 miles. At 90% it now shows 262 miles and it used to be 288 miles. At 80% it now shows 240 miles and it used to be like 260 miles.

My commute has been about 45-50 miles daily. I usually charge to 80% on schedule charging for 830am. I always arrive back home with 60-70% soc. And plug it in every night so that it's back to 80% in the morning on my 50amp outlet.

Have I been doing this wrong I was told to keep between 20% and 80% which I have been for the most part I have only gone below 20% on 2 long trips down to about 10%.

My summer average driving is 230-235 watts per mile while my winter driving averages about 280 watts per mile.

My lifetime average says 252 watts per mile.

Does the computer now show the milage based on the lifetime watts per mile cause at 75000 watts for the batter pack (75kw) if we divide to 252 watts per mile that's about 297 miles of range from 0-100%. That seems close to the 294 miles it reads now.

Has tesla changed the way the range is now displayed based on the history of the watts per mile.

Because in the summer I drive about 230-235 watts per mile and at that rate it should display more like 319 miles which is what it used to show when the car was new.

I think tesla should show the range based on the average of one of the 3 trip calculators


See we can setup A B trips, Since last Charge and Life time.


I have it setup as

Since x time
Since last charge
Summer Range (I reset this when it's winter)
Lifetime


For example right now plunder summer range it shows 234 watts per mile for the last 5,000 miles.

For lifetime it shows 252 watts per mile for 17,300 miles

 

[mrgoogle]

So i created a ticket and sent this chart. That is response i got:

It is their way of saying F that, you lost the battery lottery.

Everything you do to treat the battery well is futile. Also: -10% is peeeerfectly fine..

Your batty is the first that is almost as bad as our SR+ with -12%. Ask SoH and they won’t tell you more then “it is as expected, no errors, fits the fleet”

I am going through Germany in a few days, so It’s going to be 170-200+ km/h where I deem it safe (and where it’s legal). After that I will drive much in the mountains and kick it hard, making sure to really make use of the battery.

Will report any differences after holiday when I am back to NL.

Driving fast for long trips in Germany + superchargers in between definitely makes good use of the battery and the cooling system can be very loud!

 

[pdx_m3s]

I charged my May-2019 SR+ to 100% for the first time today, which reached 230 miles. So 4% degradation.

However, it also achieved a 209 wH/mile average to the Oregon coast and back (200 mile trip), which is 7% better than EPA.

Not bad for a $35k car.

 

[Celledral]

I charged my May-2019 SR+ to 100% for the first time today, which reached 230 miles. So 4% degradation.

However, it also achieved a 209 wH/mile average to the Oregon coast and back (200 mile trip), which is 7% better than EPA.

Not bad for a $35k car.

230 sounds amazing, I'm currently sitting at 212-216 @ 100% June-2019

 

[pl8dlikafiddle]

230 sounds amazing, I'm currently sitting at 212-216 @ 100% June-2019

I feel ya...I'm in the same boat, 211-215 @ 100% and it recently just rolled over 20,000 miles. August 2019 SR+. We definitely didn't win the battery lottery.

I've actually contemplated selling the car to Carvana and buying a new SR+ @ $37,990. Carvana offer was $35,500. Amazing depreciation for a car just short of a year old. I actually love the car other than its current battery state, so I decided to hold onto it and rely on the battery warranty.

 

[wilson502]

Im at about 8500 miles, mines sitting around 225 miles or so at 100%. My nominal full pack in SMT has been hovering around 49.2-49.4 kwh.

 

[rreinha]

Yeah, I figured I was doing it mostly right given my range at almost 20,000 miles on the odometer is in the 90% percentile.

View attachment 562908

I am 2 weeks short of 1 year with 21,678 miles and for the last 11,000 miIes have only seen 285 as max range Tesla says this is normal,
new on July 31st 2019 it was 301 miles and the only time it was that high.
Why did I pay extra for only 35 miles?

 

[pdx_m3s]

I am 2 weeks short of 1 year with 21,678 miles and for the last 11,000 miIes have only seen 285 as max range Tesla says this is normal,
new on July 31st 2019 it was 301 miles and the only time it was that high.
Why did I pay extra for only 35 miles?

Well, the SR+ would likely see similar degradation, so your paying for more than 35 miles.

 

[timmy818]

damn I'm on the fence of being the set it and forget it at 90% because i dont have a charger at home. (I have a 7 watt J-772 public free charger right next to me)

Rather than at 80% and have the chance to go into the low to mid 20s battery %.


Does it really make a difference?

 

[pdx_m3s]

damn I'm on the fence of being the set it and forget it at 90% because i dont have a charger at home. (I have a 7 watt J-772 public free charger right next to me)

Rather than at 80% and have the chance to go into the low to mid 20s battery %.


Does it really make a difference?

If I had to pick, I would go for 90% if that meant I didn’t reach lower states of charge. From what I’ve gathered, sitting at lower states of charge is harder on the cells than sitting at 90%.

 

[Zoomit]

From what I’ve gathered, sitting at lower states of charge is harder on the cells than sitting at 90%.

Ehh, if it's really low and cold. Tesla states, in the documents they file with the EPA, to store the packs between 15 and 50% SOC. (Thread with link.)

I think the "real" risk is that the user unexpectedly discharges the battery to 0% and let's it sit. That should definitely be avoided.

There shouldn't be a question that 20% to 80% is technically gentler for the battery than 30 to 90%, but the difference in degradation would be very small. I don't do that personally because I like the higher power available at high SOC. Others may want additional margin for unplanned trips or bad weather.

 

[mrgoogle]

I am 2 weeks short of 1 year with 21,678 miles and for the last 11,000 miIes have only seen 285 as max range Tesla says this is normal,
new on July 31st 2019 it was 301 miles and the only time it was that high.
Why did I pay extra for only 35 miles?

At best you get 240miles at new. (the my2020 rounded up to 250, 240 rated version was 246 originally or something close)

In reality our SR+ only has 210mi/240 and we got it like that.. Tesla tells that is normal.

The Longrange battery is only guaranteed to have the SR+ battery promised rated range if that makes sense... (because Tesla does nothing with lost capacity unless it is more then -30%)