Model 3 SR+ LFP Battery Range, Degradation, etc Discussion

[AAKEE]

The [Square root of time] calendar aging behaviour is most certainly valid for these LFP’s as well, as it is for all lithium batteries.

The reason for the calendar aging is the build up of SEI, which in turn protects the battery by reducing the rate of the calendar aging.

We do not need to be worried about that the calendar aging continue at a high rate.
It will follow the square root of time. It might bee that the BMS has hard measuring the real capacity so in a short time interval it might look different.

Cyclic aging is very small for these cells do we can disregard it.

So the degradation will flatten.

Teslafi show two different starting ranges.
The calculated average combines these, so it doenst work. But drawing a approximate line for each starting range show a clear square root form, specially for the higher range version.

 

[Mattmo]

New post here, but have been following for a little bit.
Sept. 2021 Model 3 SR+ LFP with about 31,000 miles.
Original range = 253 miles.
Current estimated range = 239

 

[gtg465x]

New post here, but have been following for a little bit.
Sept. 2021 Model 3 SR+ LFP with about 31,000 miles.
Original range = 253 miles.
Current estimated range = 239

Sounds like it's tracking about the same as the 60.5 kWh LFP battery. If you look at previous page, 60.5 kWh batteries are at 260/273 after 20 months, which would equate to about 241 in your car ((260 / 273) * 253), so 239 after 23 months sounds about right.

 

[Baluchi]

New post here, but have been following for a little bit.
Sept. 2021 Model 3 SR+ LFP with about 31,000 miles.
Original range = 253 miles.
Current estimated range = 239

We have the same car except I've got nearly twice your mileage. My current range is 238 miles. So the difference of 31,000 vs 59,000 miles equals one single mile of range.

Calendar degradation ftw.

 

[nitynity]

Picked up my M3 RWD 8 months ago. Used to charge to 100% couple times a week ( level 2 charger) since it was driven like 60-70 miles daily. Then we moved out of state. So ended up using Tesla super charger for a month or so weekly since we were renting and no chargers nearby. Now again using Level 2 charger. I just noticed the 100% charge capacity dropped from 272 to 266 miles. Is it normal degradation rate? Or am I doing something wrong that’s expediting the degradation?

Might start driving even more miles weekly and would require charging every two days or so. Should I stop at 80% or 100% charge moving forward?

Total miles driven so far - 8800 in 8 months.

 

[Sophias_dad]

2.2% loss over 8800 miles and 8 months!

Please do a search. That is not even enough to be called noise. In an ICE car you wouldn't even notice 2.2% loss.

That is probably LESS than a normal degradation rate.

 

[tgrobbo]

There’s a bloke on an Aussie Tesla FB page who’s got a 2021 LFP M3 with 226,000km - he charges to 100% every day and does a lot of fast charging on the road. His displayed range at 100% is 401km, which is a 5.4% drop from his initial 424km. He’s actually done a battery test too, came out at 91% capacity, which doesn’t marry up with the displayed range. Interesting eh.

 

[Bouba]

Ok..it’s not LFP...but that data will take a while to arrive...

Tesla gives update on battery degradation: only 12% after 200,000 miles

Tesla has released a rare update on the battery degradation in its electric cars. The automaker claims its batteries only...

electrek.co

 

[gtg465x]

Picked up my M3 RWD 8 months ago. Used to charge to 100% couple times a week ( level 2 charger) since it was driven like 60-70 miles daily. Then we moved out of state. So ended up using Tesla super charger for a month or so weekly since we were renting and no chargers nearby. Now again using Level 2 charger. I just noticed the 100% charge capacity dropped from 272 to 266 miles. Is it normal degradation rate? Or am I doing something wrong that’s expediting the degradation?

Might start driving even more miles weekly and would require charging every two days or so. Should I stop at 80% or 100% charge moving forward?

Total miles driven so far - 8800 in 8 months.

Completely normal. Average after 8 months is 266. Important to remember that degradation is fastest in the beginning, but slows down with time.

 

[pipp]

Good luck


good luck on this! I suddenly dropped a few more miles, so if you get any decent results I will follow your lead. I charge to 55% every day and in the last 2 or 3 days that equals 131 miles of range, which projects out to be 238 miles at 100%, a 5-mile loss. This after going for months stabilized at 243 miles…

The car is now 2 years old and has 13,700 miles on it. For the past couple months I have been running through full cycles, charging to 100% and then running the car down to a couple miles, then blasting the air conditioner to get it down to 0 miles. Doing this didn’t move the needle on the miles for a full charge, which has stayed at 239 miles (14 miles or 5.5% less than when it was new) But then I realized that I had screwed up by charging as soon as the car got to 0 miles as opposed to letting the car sleep a bit before charging, and so I repeated the process a couple more consecutive cycles and charged after the car had a few hours to sleep. Same difference, 239 miles reported for a full charge, which in my environment with my driving style yields roughly 175 real miles. I’m inclined to believe that all my various charging habits (super chargers, level 1 and level 2 charging to anywhere from 55% to 100%) have not made much of a difference, and that the car was simply fated to lose 5.5% over 2 years, regardless…

 

[m73b54]

My M3 RWD 11 months old with almost 30k miles shows 264mi at 100%. But interestingly, for the first 3-4 miles after full charge the range value doesn't decrease - it stays at 264. Does anyone notice something like that?

 

[DuncanM]

My M3 RWD 11 months old with almost 30k miles shows 264mi at 100%. But interestingly, for the first 3-4 miles after full charge the range value doesn't decrease - it stays at 264. Does anyone notice something like that?

Probably means that the range is ~264.5 and it takes a while to drop below 264.

 

[3sr+buyer]

My M3 RWD 11 months old with almost 30k miles shows 264mi at 100%. But interestingly, for the first 3-4 miles after full charge the range value doesn't decrease - it stays at 264. Does anyone notice something like that?

If you leave the energy screen drive tab on when you start driving after charging to 100%, this phenomenon becomes obvious after a few miles of driving.

 

[tgrobbo]

The car is now 2 years old and has 13,700 miles on it. For the past couple months I have been running through full cycles, charging to 100% and then running the car down to a couple miles, then blasting the air conditioner to get it down to 0 miles. Doing this didn’t move the needle on the miles for a full charge, which has stayed at 239 miles (14 miles or 5.5% less than when it was new) But then I realized that I had screwed up by charging as soon as the car got to 0 miles as opposed to letting the car sleep a bit before charging, and so I repeated the process a couple more consecutive cycles and charged after the car had a few hours to sleep. Same difference, 239 miles reported for a full charge, which in my environment with my driving style yields roughly 175 real miles. I’m inclined to believe that all my various charging habits (super chargers, level 1 and level 2 charging to anywhere from 55% to 100%) have not made much of a difference, and that the car was simply fated to lose 5.5% over 2 years, regardless…

Yep it seems everyone has lost 5.5% after two years - even the guy who’s done 140,000 miles (226km) and charged (or supercharged) to 100% daily or several times a day. Given that he tested his battery properly, and the result actually showed a 9% loss of capacity, my hypothesis could still be true - that the loss of displayed range over time is predetermined and not based on the individual car. Of course 9% loss of capacity may not equate to a 9% loss of range, I get that, but I’m still a bit suspect.

 

[m73b54]

Probably means that the range is ~264.5 and it takes a while to drop below 264.

It stays at 264 for 3-4 miles. Looks like the actual range is 267-268 but the car doesn't want to show it. And chart with the projected range is flat (horizontal).

 

[hgmichna]

I've said it already, and I'll say it again. The data is incorrect if taken from uncalibrated batteries. It underreads the range.

In my 9-months-old Model 3 about half of the apparent range loss, almost 3% of the displayed range, disappeared after two complete calibration sessions. I have driven the battery down to between 5% and 10% before charging and calibrating.

 

[m73b54]

I've said it already, and I'll say it again. The data is incorrect if taken from uncalibrated batteries. It underreads the range.

In my 9-months-old Model 3 about half of the apparent range loss, almost 3% of the displayed range, disappeared after two complete calibration sessions. I have driven the battery down to between 5% and 10% before charging and calibrating.

Sorry, how do you calibrate the battery?

 

[hgmichna]

Sorry, how do you calibrate the battery?

Just charge and wait until it is fully charged. If not already well calibrated, it will automatically go into calibration mode and show it on the display. Calibration can take up to 20 minutes.

During calibration the displayed mileage rises. I have also seen the mileage rise further shortly after calibration while I drove off the charger.

 

[pipp]

Fooled It stays at 264 for 3-4 miles. Looks like the actual range is 267-268 but the car doesn't want to show it. And chart with the projected range is flat (horizontal).

I’ve noticed some latency when trying to drain the battery down to zero miles: I’ll drive the car to the top of the hill I live on and turn back down the hill when it reaches 0 miles. Pulling into my driveway after going down the hill, at first I was fooled by the display still showing 0 miles (even though I had just gone downhill for a mile). But by the time I had the car parked in the garage, it was registering the re-gen miles and showing that it now actually had 2 or 3 miles instead of zero. So it could easily take a couple of minutes or more for the bms to finalize its estimate of how much power remains…

 

[tgrobbo]

I’ve noticed some latency when trying to drain the battery down to zero miles: I’ll drive the car to the top of the hill I live on and turn back down the hill when it reaches 0 miles. Pulling into my driveway after going down the hill, at first I was fooled by the display still showing 0 miles (even though I had just gone downhill for a mile). But by the time I had the car parked in the garage, it was registering the re-gen miles and showing that it now actually had 2 or 3 miles instead of zero. So it could easily take a couple of minutes or more for the bms to finalize its estimate of how much power remains…

Yeah well if you think about it, the car probably estimates range based on what’s been happening at the drive unit, not the battery itself (because it can’t tell what’s happening with the battery a lot of the time) It probably does a whole heap of maths to estimate your range or battery percentage, based on your wh/m and the known capacity of the battery. It figures that it might struggle with this maths at either end of the SOC. It also explains why they want a full charge once a week, so the car can start calculating from 100% again. The calculations would start to get pretty complicated and inaccurate if you never went back to 100%.