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

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Could be... no evidence to show it’s not, right? Or just as much evidence as some conspiracy theory that Tesla is hoarding capacity to avoid warrantee claims :rolleyes:

As conspiracy theories go it's pretty widespread. There were a couple of model S battery fires in parking garages and then a software update or two later tons of messages on threads about old model S cars getting their battery capacity nerfed. About the same time the AWD model 3 had the same issue.
 
As conspiracy theories go it's pretty widespread. There were a couple of model S battery fires in parking garages and then a software update or two later tons of messages on threads about old model S cars getting their battery capacity nerfed. About the same time the AWD model 3 had the same issue.
Nerfing implies Tesla has intentionally capped the battery voltage to something less than a typical full charge or 4.2V per cell. I've learned a few things reading endless threads on this :) Nerfing occurred on a "small" number of older Model S vehicles. I have seen nothing on TMC to indicate Tesla has done anything like this to the Model 3 or newer S and X. It seems like most of the variations on the 3 are either truly defective batteries or the result of the way BMS calculates range, which seems to change with OTA updates.
 
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Nerfing implies Tesla has intentionally capped the battery voltage to something less than a typical full charge or 4.2V per cell. I've learned a few things reading endless threads on this :) Nerfing occurred on a "small" number of older Model S vehicles. I have seen nothing on TMC to indicate Tesla has done anything like this to the Model 3 or newer S and X. It seems like most of the variations on the 3 are either truly defective batteries or the result of the way BMS calculates range, which seems to change with OTA updates.

I'm just saying that the nerfing of the old model S vehicles happened right around the time that the BMS went out of wack on the model 3s. My speculation is Tesla went messing with the BMS. I had 0 mile range loss until June 2019 and then 7-9 %shortly after that with not many miles more. Most people seeing the issue are seeing changes in the June-August time frame. Again all based on what I've seen on threads.
 
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I'm just saying that the nerfing of the old model S vehicles happened right around the time that the BMS went out of wack on the model 3s. My speculation is Tesla went messing with the BMS. I had 0 mile range loss until June 2019 and then 7-9 %shortly after that with not many miles more. Most people seeing the issue are seeing changes in the June-August time frame. Again all based on what I've seen on threads.
You are totally correct. I have noticed the same thing on my vehicle. Thankfully, it doesn't appear to affect real range, just the rated range which doesn't really matter.
 
They both use lithium batteries brah... lithium chemistry is lithium chemistry. You don’t slap a T on it and change the laws of physics, yet.

Right. A little battery cylinder is a little battery cylinder, they're just cells, and it doesn't matter how you charge it, or discharge it, or balance it with neighbors, or how you manage the heat.

No, wait, that's backwards - it TOTALLY matters how you charge, discharge, balance, and manage the heat. And that's the actual thing that Tesla innovated on the most, and that the other manufacturers are the furthest behind on.
 
As last option you can always do a real capacity measurement using Tesla Bjorn's method. For better accuracy try to get as low as possible on the trip.


I like the various various descriptions on How to correctly measure battery degradation in Tesla from Bjorn's.

However, I don't have often the opportunity to charge to 100%,
then immediatly drive about 300 miles until getting 10% and report the kWh consumption.

Note: This is exactly the way I test my smartphone portable batteries, by decharging the battery into a load, and measure the total Amp Hour.

Well, this was not recommended by Bjorn, however it is quite easy to get back home with 10% and charge at low speed until 100%.

I have a small $20 Watt meter next to my UMC, so I can measure the exact amount of energy used when charging.

This include both the battery charging and the various losses.

However, I can reproduce the same measurements overtime, and the lost are proportional to the energy used when charging.

I can estimate the energy lost when charging by comparing the total energy needed to get 100%
and the energy that the car used when doing a seasonal road trip until I reach 10%.

My point is that, instead of reading the total range given by the car,
value which can change just because of new update range calculation algorithm,
I measure the actual kWh capacity of the battery when charging it.

Note: I agree that discharging the battery provides a better measurement (see Bjorn method) than charging,
but I think that measuring the charing energy used is more consistent that just reading the given mileage.

In fact what would be more usefull, to check if the battery was corectly balanced,
would be to access the individual cells or modules status like the Leaf Spy App.
(I imagine that Tesla has this capabily to do so, but this is not available)
 
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I'm just saying that the nerfing of the old model S vehicles happened right around the time that the BMS went out of wack on the model 3s. My speculation is Tesla went messing with the BMS. I had 0 mile range loss until June 2019 and then 7-9 %shortly after that with not many miles more. Most people seeing the issue are seeing changes in the June-August time frame. Again all based on what I've seen on threads.
I went through and checked my history on Tesafi, and can't see a major drop that I could easily point to a specific update. While I was browsing, I can't pin the drop on % charged, outside temp, or firmware version. I was really hoping to see a smoking gun in the data.
 
No matter how you charge it, manage heat, eat, etc, both batteries will degrade. Which was the actual point.

But there will be a huge difference in how long the battery lasts, which is the actual point.

It's like you're saying that you and I are both going to die, so it doesn't matter if we jump in front of a moving bus. No, my friend, it makes a big difference in our lives.
 
But there will be a huge difference in how long the battery lasts, which is the actual point.

what makes you say that, my point was that both batteries will degrade... I imagine I know what my point was with a comparison I made.

It's like you're saying that you and I are both going to die,

Yes...

so it doesn't matter if we jump in front of a moving bus. No, my friend, it makes a big difference in our lives.

No... we will both die. Like a cellphone battery. Like a Tesla. Like a dog. That was my point. You adding qualifiers “but we will all die differently” is your spin.
 
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what makes you say that, my point was that both batteries will degrade... I imagine I know what my point was with a comparison I made.

Well, if you're all that matters to you, then sure.

But I was talking about the point of the conversation, which involves you, but also me, and also the others in this conversation.

And the point was "degradation curves," even though you are not the person I'm quoting. When there are very different curves, simply saying they both degrade isn't an adequate comparison.
 
Well, if you're all that matters to you, then sure.

it was my point I was making, I’m the one that brought up phone batteries as being similar to car batteries? That a phone battery and car battery are similar... and they are... right? Yes.

When there are very different curves,

OPs post seems to indicate otherwise... but like I said I think his method for collecting data is flawed.
 
Also, balancing is different than calibration, and should happen any time the battery is finished charging and still plugged in (probably above a certain percent like 80, but I don't know the cut off exactly)
Prior Tesla models didn't trigger balancing until 93% SOC. There is a historic reason for this number, that's where an original set point was at to for Trip/not Trip (forget the wording) before Tesla created the slider that has 1% increments.

It is likely, although not 100% confirmed as far as I know, that the Model 3 also doesn't begin balancing until SOC hits 93%.
 
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m3 LR 11k miles, 9 months old

My regular 80% charge went from being 252 to 246 over two or three months and started to hit 245 recently, signaling its continuing to drop. About 1 mike loss very 12 or so days. I charged to 100% as suggested by Tesla and only got to 304, which dropped to 303 as soon as I stepped in the vehicle, a 6-7 mile, 2.2% degradation. After running it down, my 80% charge was again 246, also a 6 mile, 2.2% degradation.

Is this something others have seen? I’ve read other posts with mostly higher sudden drops, so I wonder if after 9 months and 11k miles, that 2.2% degradation suddenly (over a short period of time, and not gradually over life of vehicle) is possible? But I’ve also read that other LR owners continue to hit their usual charge state even after 30k miles. What’s everyone else’s current range experience?
 
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m3 LR 11k miles, 9 months old

My regular 80% charge went from being 252 to 246 over two or three months and started to hit 245 recently. I charged to 100% as suggested by Tesla and only got to 304, which dropped to 303 as soon as I stepped in the vehicle, a 2.2% degradation. After running it down, my 80% charge was again 246, also 2.2% degradation. Is this something others have seen? I’ve read other posts with mostly higher sudden drops, so I wonder if after 9 months and 11k miles, that 2.2% degradation is possible? But I’ve also read that other LR owners continue to hit their usual charge state even after 30k miles. What’s everyone else’s current range experience?

There are many threads on this topic. Your result is perfectly normal. No one knows whether it is "real," software issues, or simple miscalculation of the BMS SoC estimation.