Battery degradation 8% in 10 Months of ownership

[DaPatsFan]

I charged my 2022 Model S Long Range to 100% after almost 4 months today and the range is 373 miles. In December last year I was at 399 miles. I originally had the 21” wheels but since Tesla decided to give me Summer Tires , I had to switch to the 19” All season tire package. Is a 7% degradation normal so quickly? My normal charging pattern is that I charge to 90% every night using my wall charger. Anybody experienced something similar? Total miles driven = 10800

 

[mswlogo]

It could partly be calibration. Do you occasionally run the battery low, like down to 20%? If you constantly run say 50% to 90% it can throw off the calibration.

Also, despite Elon’s comments, Constantly leaving it at 90% isn’t ideal for the battery. Unless you need that range every day, shoot for lower.

I keep mine at 80% and will charge to 90 or 100% as needed. Which isn’t often.

 

[DerbyDave]

Around 5% is normal for drop in the first year, then it is much less following years. I assume you did the wheel recalibration after switching to 19" wheels, because that should re-add about 5 % on its own. Also @mswlogo has good points. 7% is a little high, but it could be also due to calibration, like @mswlogo says.

 

[mswlogo]

Around 5% is normal for drop in the first year, then it is much less following years. I assume you did the wheel recalibration after switching to 19" wheels, because that should re-add about 5 % on its own. Also @mswlogo has good points. 7% is a little high, but it could be also due to calibration, like @mswlogo says.

Good point. I think 373 is almost exactly what 21” wheel setting would show (when brand new). If that’s the case he’s had almost no degradation.

 

[DaPatsFan]

Good point. I think 373 is almost exactly what 21” wheel setting would show (when brand new). If that’s the case he’s had almost no degradation.

No, I recalibrated when I switched to the 19” wheels and went up from 370 to 399. I wonder if cold weather has been a factor. I’m in the Boston area and this degradation has happened during the winter.

 

[DayTrippin]

Why are you charging to 90%? The closer you can keep your average SoC to about 55% the, less degradation your battery will experience. This is even more crucial on hot days. I keep my avg. SoC at about 50% and have minimal degradation in 10k miles living in a very hot climate (TX and FL). Absolutely no need to charge to 90% unless you need to drive several hundred miles. I wish Tesla had an even lower limit for what you can keep the charge level than 50%.

 

[DerbyDave]

I agree @DayTrippin. Figure the range you normally need for daily driving and for an emergency and charge to that level. If a big ice storm is coming, or worries about power going out for days, increase charge. This is what is good about a battery that gets ~400 mile range. I also normally charge at 32A at home, which is fine in a non-emergency, local travel environment, and a garage helps both in winter and in summer. In winter I increase the charge to 70 or 80 percent due to the decreased cold range, but in the summer, 50-60 percent is fine for my needs. Some don't have a garage or a home charger, and the battery will still be fine -- just perhaps a bit more loss of range.

 

[beatle]

Charging to 90% shouldn't be a problem. My 2015 had 5% degradation when I sold it earlier this year, and my 2019 has just over 4% degradation. Though I wasn't the original owner of either car, I always charge to 90%.

7% in a year seems unusual to me.

 

[DayTrippin]

Ultimately it is your car and do what you want. There is a ton of research out there regarding Li-on batteries that are used in the Tesla packs for the LR models.

Here is a direct quote from the site below. Infer what you want from it. A lot of good charts and info on the page linked below. Especially round depth of discharge as well.

"Lithium-ion suffers from stress when exposed to heat, so does keeping a cell at a high charge voltage. A battery dwelling above 30°C (86°F) is considered elevated temperature and for most Li-ion a voltage above 4.10V/cell is deemed as high voltage. Exposing the battery to high temperature and dwelling in a full state-of-charge for an extended time can be more stressful than cycling. Table 3 demonstrates capacity loss as a function of temperature and SoC."

BU-808: How to Prolong Lithium-based Batteries

BU meta description needed...

batteryuniversity.com

 

[beatle]

90% has each cell around 4.09v. From that site:

Most Li-ions charge to 4.20V/cell, and every reduction in peak charge voltage of 0.10V/cell is said to double the cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.0V/cell should deliver 1,200–2,000 and 3.90V/cell should provide 2,400–4,000 cycles.​

​

Even if you only get 800 cycles out of the pack, at an average of 90% efficiency, you're still getting over 240k miles out of the battery which is pretty respectable.

Higher voltage also means more power. Power at different SoCs is less pronounced in the newest cars, but on my P85DL, it was a noticeable difference as the SoC dropped. Even at 80% my butt dyno could detect a difference in power. Back to the OP's question, I still don't think charging to 90% would degrade the battery by 7% in a year. I would sign up for a data logging service like TeslaFi and continue to monitor the car.

 

[DayTrippin]

I can't measure any drop off in performance 0-60 on my 2022 MS LR until I am under 50% SoC. There was more variation in run to run that the impact the SoC on my performance. From 0-100 mph, it might have dropped a tenth when under 70% SoC. Another tenth when under 50%.

All I can say is I have 10k miles on my S in a very hot environment, kept the SoC around 50%, about 3k miles supercharging (typically 20-65% on a trip) almost never charge over 80%, and I have about 1-2% degradation (depending on what source I believe - TeslaFi says 1%) in over a year.

Considering my car has spent its entire life in Texas or Florida (temps up to 110F) or driving between them, my degradation is excellent, especially considering the high temps. My 2022 M3 LR, is showing similar degradation numbers as my S in the same environment. So I'll just keep doing what I am doing.

Could be an issue with the OPs car but no downside to keeping your SoC lower rather than higher assuming you have enough range. I have both a 32A and 48A charger so I can top up pretty quickly.

 

[father_of_6]

I've set my daily charge limit to 50% and just recharge between drives if necessary.

I think a lot of times these drops in estimated range are actually due to BMS prediction issues and not battery capacity - which still technically limits your range as far as I understand.

Check out this post:

How I Recovered Half of my Battery's Lost Capacity

Like many others, I have been concerned with loss of 100% indicated battery range on one of my Model 3s. My P3D (build date 9/13/2018, delivery date 10/8/2018) had gotten down to 270.3 miles at 100% charge on January 20, 2020, at about 30,700 miles, which is a loss of 40.8 miles since the car...

teslamotorsclub.com

 

[DerbyDave]

Tesla seems to have helped reduce the temperature issue with extreme battery temperature management, at least if the car is plugged in. (and maybe if overheat protection is engaged?)

 

[DrModi]

I have a 2021 Tesla Model S Long Range and having a similar issue. My car came with the 21” wheels and I used to get ~375 miles up until last year. But recently I charged to 100% for a road trip and now I get 354 miles. I just crossed 10k miles. I never charged beyond 80% unless it was a road trip and predominantly charge at home. The degradation feels more than normal.

 

[aerodyne]

I have a 2021 Tesla Model S Long Range and having a similar issue. My car came with the 21” wheels and I used to get ~375 miles up until last year. But recently I charged to 100% for a road trip and now I get 354 miles. I just crossed 10k miles. I never charged beyond 80% unless it was a road trip and predominantly charge at home. The degradation feels more than normal.

I tend to agree, but it is likely that degradation will level out after the first year. This has been observed though fleet data from various sources.

In my case, '22 MSLR, 4.5k miles, a year old, RR still above 400, so less than 1%.

Never been above 85%, or below 25% SoC.

The new cars have a good warranty, so should you have excessive degradation, likely you will get a new pack before the warranty runs out.

 

[mswlogo]

I tend to agree, but it is likely that degradation will level out after the first year. This has been observed though fleet data from various sources.

In my case, '22 MSLR, 4.5k miles, a year old, RR still above 400, so less than 1%.

Never been above 85%, or below 25% SoC.

The new cars have a good warranty, so should you have excessive degradation, likely you will get a new pack before the warranty runs out.

If you have never been above 85% how do you know what your actual degradation is. That’s the only way to know for sure.

 

[brkaus]

Changing the wheel type on my 2017s didn’t change the range displayed on the dash at all. Originally had 19”. Sent with 21” for last set of tires, now now back to 19”.

I can go back and forth between wheel side in the wheel configuration and displayed range isn’t changing.

There is also an odd bug there. I can only change the wheel style if changing the size at the same time.

 

[aerodyne]

If you have never been above 85% how do you know what your actual degradation is. That’s the only way to know for sure.

Perhaps, but I'm pretty sure the degradation is not more than reported by Teslafi.

3 years experience on the old 85 pack indicates charging above 80% not required to get a good estimate of capacity or degradation. Backed up by BMS data as reported by SMT and Teslafi.

On a related note, on the new MS, seeing a very minor but gradual improvement in range when storing at 50-60% when compared to the 2022 MS Fleet.

Currently out of country, car stored at 55%, will see what happens when I get back and charge to 55-62%. Expect 400+ RM and about 1% degradation after one year since build.