Candleflame
Active Member
well case studies dont mean much. we have to remain objective. there will always be people who luck out and some who dont.
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Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health
- Thread starter KK_RedM3
- Start date
well case studies dont mean much. we have to remain objective. there will always be people who luck out and some who dont.
Candleflame
Active Member
The old 2017/2018 RWD Model 3s hide degradation until you drop below 310/322miles degradation, unless you have the 322 mile patch. Then you have to pick 322 miles as the starting point.
I lose a few miles of range every time I charge. My loss is now 3.56% over 2000 miles.
Bar3
Member
I am not sure what you are experiencing, but I can tell you that I did the math and my late 2019 battery has been hit with about 13% or so degradation. I was able to easily calculate how many kWh my pack would hold.
Not good Bar. Charged to 90% last night, lost more range. I’m gonna contact Tesla to see if they can remotely reset the BMS.
Bar3
Member
Let me know how that goes because they have been very shady with my battery. They didn’t want to reset and they don’t even let you see your own battery health report. I don’t understand why... It’s my car, I own it... why can’t I see the reports?
Tesla service called prior to my appointment to tell me that they ran diagnostic, and that there is nothing wrong with my battery. They canceled my appointment. They asked that I run my battery down to below 20% and then up to 90ish%. I did this once so far, and my battery is now up to 278 miles when I use the app to go to 100%.
They try to dodge the why, but it’s simple: “It’s classified”
That’s what they eventually after 3(!) battery service visits told me (and indirectly also told me that I am At bottom of fleet)
Now: Read your warranty about the -30% guaranteed, but only if Tesla determines it actually is -30% and “only tesla can make this judgement” part in the warranty...
Yes it is very real, because it basically means you only get warranty if they deem it -30% or worse. This is impossible for the owner to determine, because Tesla is very clear consumer cant know Anything about it.
Bar3
Member
You’re totally right about this. I think this may fall flat on teslas face one day.
AlanSubie4Life
Efficiency Obsessed Member
It actually is possible to determine. Don’t have to go to Tesla or really depend on them at all for initial determination.
For a 2018/2019AWD, depending on one’s interpretation of initial capacity (76kWh vs (actual) ~78kWh), the 30% loss threshold is met at:
217 rated miles (217rmi*245Wh/rmi/76kWh = 70%)
or
223 rated miles (223rmi*245Wh/rmi/~78kWh = 70%)
Just wait for those numbers at 100% and then contact Tesla.
Obviously the initial value has some importance but it is not huge. It really is ~78kWh though (that is what SMT and the EPA say!).
In any case if you’re already at 220 rated miles at 100% (AWD 2018/2019 only) then you’re definitely going to get a claim unless you are super high mileage (you’ve still got a lot of time under warranty to get below the 217 rmi threshold and no reason to think you won’t if you’ve already lost 90 miles in 2 years).
MarcG
Active Member
Isn’t that the problem though? Tesla could claim whatever they want on initial capacity, since all 3rd party tools to measure capacity are “unofficial” even if reading from the CAN bus, and there is high variability anyway between packs so it’s really hard to tell.
The most likely scenario is that Tesla will say it’s based on miles, e.g. 310 RM is the 100% max when new so take 30% deg from that and you have to hit 217 and lower to make a claim.
Of course, we think 310 is an artificial UI cap at first, so there is actually more RM to start with, which hides some initial degradation, giving Tesla a pass for another few % beyond the 30% they guarantee.
Given deg curves, we lose the most up front, then it’s pretty slow over the years/miles. So I highly doubt many at all will hit Tesla’s 30% deg definition within the warranty period.
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AlanSubie4Life
Efficiency Obsessed Member
I guess it depends on your definition of “problem.” I feel like 2% on top of 30% is kind of splitting hairs. Obviously it could matter for a few unlucky people in 6 years who JUST miss the warranty threshold.
My point was that anyone can tell exactly how much energy their pack can hold - they don’t need to ask Tesla! Everyone knows the approximate status of their pack. It is right there on the screen - nothing is hidden!
The only thing that is in dispute (and it is a minor issue!) is the initial capacity. Just not that much of an issue....
I feel like an AWD user with 220 rated miles after 2 years is going to likely have a pretty solid claim with Tesla in the near future!
Let me
Rephrase that: I think it is very easy to determine also, but exact pack capacity is also secret when you ask them.
In short: read exact warranty about it, it clearly states -only Tesla- can say/prove if they deem
It -30%
(also read other responds below)
That’s exactly a part of the problem! Let me give our car as example:
Highest rated miles it ever had (first week) was only 369km (which is 229 miles of the 240..!) at that point I already made an appointment, because I knew other people were indeed starting at 240/240mi...
Tesla literally told me “if you started at 229mi and it’s “only” down to 206 rated, you gerting -30% is different, because actual pack capacity isn’t made public or advertised”
Only we at Tesla can determine that at our own will. If the battery stops working it will automatically give an error on your screen...
Again; that is not my experience unfortunately, Tesla will try and ghost me, talk about losing kWh because climate isn’t accounted in energy use, energy hold back by the car, temp. imbalance, cold weather, too hot weather, tyre pressure... Basically every other “range” aspect they spam you with, and disregard my teribble battery capacity.
My 100% to -0% capacity (at ideal weather and flat road) and 60-65mph is 44.4 kWh useable. It’s actually just under 40kWh with a 90% charge.
Don’t get me wrong, I think it’s easy to determine Pack capacity also, but try and explain service center why/how you determined capacity and they give you all sorts of reasons why that’s invalid. (even when doing a trip without stopping, ideal weather, ideal speed, flat road from full to near zero, without forgetting to also preheat for 3-4hours!)
for context: I am a trained (ex) car mechanic, at some point almost started to work for Tesla as a mechanic. I also build my own electric moped and programmed BMS and such (and I have ScanMyTesla also). So I have been in most cases more informed then the mechanic that sometimes also came to me about the capacity. (Always seems I was better informed in how stuff works)
AlanSubie4Life
Efficiency Obsessed Member
But that is just something they say, since you are asking people at the service center - they have no idea what the pack capacity is.
The pack capacity is not a secret. It is in the EPA documents and it’s legally required to have real world vehicles match those numbers (for a full discharge until the vehicle stops moving), when the vehicle is new. I don’t know what the tolerance allowed is, but it is supposed to be “close.” And it’s reasonable to think it will be, as EPA occasionally audits Tesla’s test results.
That is where the lawyers/arbitrators come in, I guess. Not really relevant until you are close, though!
Again, just noise from service center employees. Can be safely ignored.
When you get close to 170 rated miles for your SR+ at 100%, re-engage with Tesla.
You have SMT so you know your pack capacity and how it compares to new. That is what I would go by as your reference.
As you know, what the trip meter reads and what is usable is less relevant, since you rarely drive until the vehicle stops moving. If you only drive down to 0 rated miles and not beyond, the trip meter is always going to be about 5% less available than what SMT says is your pack capacity. Sounds like at 209 rated miles, SMT will say 45.8kWh for your pack, which is about 13% loss, which seems high, but still quite normal (especially considering you started with a crap pack/initial capacity).
I’m not convinced your starting point for warranty purposes is going to be different than anyone else’s - no one actually knows what your vehicle actually started at, even if you reported a rated range early in life of 229 rated miles in the service records. “Obviously” it started at at least 240 miles! No one can counter that (even if it did not) and it’s the most reasonable thing to assume, since that was this model’s starting range. Tesla may keep records of historical rated range but I have my doubts.
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My 2007 Z06 and my 2011 Z06 both had 25 to 26 MPG on the highway at 80 MPH on cruise control, with no headwinds. MSRP sticker on both shows 25 MPG highway.
(I realise the quote is from the first page, and yet it is still relevant
)Piling on... 2009 Honda Fit Sport rated for 7.2L/100km (33mpg) in city, 5.7L/100km (41mpg) on highway. We typically get 5.3L/100km (44mpg) with a mixed (mostly highway) commute, but I can be as "bad" as 5.8L/100km in winter (which is still better than the rating would suggest). And it's 12 years old! Our most honest "record" was a multi-day highway trip where it averaged to 5.0L/100km (47mpg) round-trip.
Same-ish story with my 2014 Honda Crosstour V6. 11.1L/100km rating in city, 7.1L/100km rating on the highway. My mixed commute was about 7.2L/100km - not stellar, but it should be closer to 8-9 or so if the ratings were to be law.
Annnd it's the same with our Model 3. My wife, no idea how she does it, manages 130Wh/km for her mixed commute while driving faster than I would to get 132Wh/km. The key thing is that even 132Wh/km is more efficient than the rating would imply. It's only Winter where we get worse than rated (but then, much worse of course).
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I find this whole "tests are inherently flawed" thing a bit weird. On one hand, sure, that's absolutely true. But the flaws aren't all against you, and there are worse (more optimistic) tests. See ranges for EVs that were based on NEDC - completely unachievable. I've actually found EPA ratings to be middlesome.
AlanSubie4Life
Efficiency Obsessed Member
I realise the quote is from the first page, and yet it is still relevant
In addition, that quote is wrong about something else... Generally speaking, the testing for range is done by Tesla and Tesla submits the EPA numbers for publication. Only audited by EPA on occasion.
The only thing the EPA usually does is post the manufacturer’s results and keep a datafile.
But we know for the most recent Model S Tesla had the EPA do the testing and the EPA left the door open overnight with the fob in the car, so it resulted in less than 400 miles. Tesla had to have the EPA re-do the testing... So it seems Tesla likes to request the EPA do the testing for them.
AlanSubie4Life
Efficiency Obsessed Member
I was just saying generally speaking. If you look at the EPA docs submitted they are generally from Tesla’s lab. There are of course exceptions (hence “generally speaking”) - what drives those I do not know (other than an audit). My understanding is the EPA expects the manufacturer to do the testing unless they decide they want to check it themselves.
AlanSubie4Life
Efficiency Obsessed Member
A little bit more support for this discussion, just for clarity here, so people can draw their conclusions. Again, of course, sometimes the EPA tests the vehicle (they decide when they want to do this, AFAIK). The actual balance of tests done at Tesla and EPA and how it is decided, I do not know, of course. For the Model S, maybe Tesla "had the EPA do the testing"...but it could also have been an EPA request. But for sure, many (most AFAIK) are done by Tesla. It's definitely more likely to get screwed up by the EPA - making sure the Tesla doesn't vampire drain is a very complicated procedure best left to experts & owners! Leaving the door open is definitely not a good idea (unlike with most cars)!
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