The good news is that as a 2021 M3P, every single such Model 3 Performance was produced with the "82.1kWh" battery, with 2170L cells. So for any replacement that doesn't put in the right part, they'll have to redo it. Putting in a smaller pack is not an option for them (there was never a 2021 Performance vehicle with a smaller pack - only the AWD had that difference for a portion of 2021). I’m referring to the US market here. The situation in Europe is more complicated, though for the Performance, I think they still get just the 2170L packs and always (for 2021) have.
Whether it's the 79KWh or 82KWh battery pack, they should know and tell me, and they should tell me the maximum (remaining) capacity. No opaque responses accepted.
You should be getting an "82.1kWh" pack, and they should be able to show you that on the diagnostics page in Service Mode, is my understanding. (I'd expect you would have had at the time of failure something like 77-79kWh available given the age of your vehicle and its location in hot, hot Riverside.) Do you know what your rated range was at 100% prior to the failure?
What would cause Tesla to reduce battery capacity from the original 82kwh for my 2021 M3P?
They haven't. Not sure what they're talking about. (It's not unusual to hear unmitigated garbage information from service personnel - this is normal for any service department, Tesla or not.)
It looks to me like they should be replacing part number: 1104423-00-T
MASTER THREAD: 2021 Model 3 - Charge data, battery discussion etc
A couple caveats:
1) The "T" letter may change.
2) In their system, the "reman" parts have a DIFFERENT part number. I suspect the LABEL on the pack (detailed in post above) will still match, though. (But sounds like you might not be getting a reman part.)
3) This information is dated and part numbers may have changed.
4) The base part number is the same for the 82.1kWh and 77.8kWh part numbers...
MASTER THREAD: 2021 Model 3 - Charge data, battery discussion etc
(The -0L- seems to show up - I assume this refers to the 2170L, so look for that in particular.)
(The short answer here is that I don't know the current model of your battery. Someone with a 2021 Model 3 Performance manufactured at exactly the same time would have to take a peek as outlined above. And I definitely don't know the exact part number for the 2022 Model 3 Performance (again, someone would have to look).
but a brand new stock battery as currently installed in all 2022 dual motor Model 3 versions.
This is correct, as far as I know. All
US-made 2022 dual motor Model 3 vehicles NOW come with the "82.1kWh" battery, as far as I know. However, in 2021 AWD, non-P vehicles, 2170L pack, they do tend to show up with a bit less capacity sometimes (between 79-80kWh rather than ~81kWh) - the reason for this is a mystery and it may no longer be happening.
That being said, I haven't been tracking 2022 vehicles much, but their ranges have increased (just like happened with later built 2021 Model 3 non-P AWDs with larger pack) as one would expect for a larger pack (for AWD, up to 358 from 353). I haven't looked at recent EPA documents either. But all the information you seek should be there for your vehicle.
Basic Search | Document Index System | US EPA
Looked quickly: 82.1kWh pulled from the AWD, 80.8kWh for the Performance, for 2022 vehicles.
(Last two pages are the "money" pages. Note the 2022 Performance test was done in July
2020 - no changes there for a while.).
These numbers mildly suggest that they may have perfected their 2170L manufacturing process, or just updated the software, with nameplate energy quantities able to be drawn (82.1kWh is the highest I have ever seen for Model 3, though keep in mind this will not be reflected necessarily in BMS values & SMT readings (typically they are always less than the EPA readings due to a difference in measurement method)).
So if they're not lying to you, and are putting in a brand new stock 2022 battery as currently installed in US market 2022 Dual Motor Model 3 versions, you have nothing to worry about. It looks like it has to be the "82.1kWh" pack; there is no other pack.
just talked to the service manager and he confirmed: all M3P have a 74kw batery since 2018, since the model was introduced, and that is what I will be getting: the same exact brand new battery pack that is installed in all new M3P. I a stumped.
This is, of course, completely false. (Not a surprise.) The 74kWh comes from the “usable” (not including buffer) capacity of the 77.8kWh pack, I believe (74.3kWh).
Good luck, let us know how it goes, and if you can, pay it back by taking a picture of your new battery label using the easy
procedure above. A brand new pack would be a wonderful outcome, and fair, given the inconvenience.
We've seen just a couple of reports of sudden massive hits (20%) to capacity on these 2170L packs. One of the prior reports nearly completely recovered after a couple weeks of driving (error in CAC value somehow?). I guess Tesla ran diagnostics on your car and didn't like what they saw; for the other situation I mention they said it was no big deal and to wait it out, and it turned out they were right (I didn't believe it but was proven wrong).
I should add: there is an easy way to tell and set your mind at ease: If your 2021 Performance vehicle after replacement shows ~315 rated miles at 100%, you have nothing to worry about. That indicates you have a very healthy battery, over 80kWh (over ~80.6kWh actually).
