How I Recovered Half of my Battery's Lost Capacity

[KenC]

It has been hanging out at the recovered level with some variance.

So it appears that I have recovered some from the low point at around 30,500 miles, and it doesn't appear to be wanting to go down any further. Not a bad result.



Not really sure what you're getting at here. It sounds like "Well, if you disregard the evidence then this is meaningless".

Well. Ummm. Yes. I guess?

Doctor comes in and says "well the MRI shows you have a large cancerous tumor". Hmmm. Well I guess if I disregard the MRI results then everything should be OK.

My only thought is that your low point, at around 30,000 miles, you said was Jan 20, which is mid-Winter, and your recovery at around 36,000 miles was in April, early-Spring. Teslafi and the app I run, Stats, use the SOC api that is temperature-affected.

Here's my data from Stats, overlaid with temperature, that shows how much the 3rd-party apps, like TeslaFi and Stats, using the temp-affected SOC api, show BMS range estimates that correlate with temp change:

Now, strangely, since Jan 24th, the temp and BMS range estimate no longer seem to be correlated. I did get a bunch of software updates in this time period, so I do wonder if something changed, whether Stats decided to use the other SOC api that isn't temp-affected, or whether Tesla changed something. Dunno, but mid-Winter I expect the BMS estimate to show 304-306miles, and I'm currently getting 309-313miles, what I would normally show mid-Summer. Strange.

Anyway, just wondering if you ran your BMS data vs ambient temps to see if there's any correlation. Yes, I know, Houston, but as you can see, even small temp changes affect the BMS range estimate that 3rd-party apps seem to use.

 

[wildguess]

It has been hanging out at the recovered level with some variance.

So it appears that I have recovered some from the low point at around 30,500 miles, and it doesn't appear to be wanting to go down any further. Not a bad result.



Not really sure what you're getting at here. It sounds like "Well, if you disregard the evidence then this is meaningless".

Well. Ummm. Yes. I guess?

Doctor comes in and says "well the MRI shows you have a large cancerous tumor". Hmmm. Well I guess if I disregard the MRI results then everything should be OK.

Thank you for your response.
I am a little bit skeptical because your method did not work for me at all.
It must have made things even worse for me.
So, I am not sure if it works in general, or it was a coincidence that it worked for you.
I began using the same technique as you at around 24.5K.
At first the rated range growth exceeded my expectations, but a bit later it dropped to a quite low level and is not recovering no matter what I am doing (2019 SR+ , 240 miles EPA rating)

 

[KenC]

Thank you for your response.
I am a little bit skeptical because your method did not work for me at all.
It must have made things even worse for me.
So, I am not sure if it works in general, or it was a coincidence that it worked for you.
I began using the same technique as you at around 24.5K.
At first the rated range growth exceeded my expectations, but a bit later it dropped to a quite low level and is not recovering no matter what I am doing (2019 SR+ , 240 miles EPA rating)
View attachment 643467

What's the green line? Interesting that your variance increased substantially after around 32k.

 

[wildguess]

What's the green line? Interesting that your variance increased substantially after around 32k.

It is average range for same cars with similar mileage.
At 32,200 miles my car updated from 2020.40.8 to 2020.44.10.1.

When the car is parked or is sleeping the BMS recalculates the range and I often see the results such as below.
The percentage dropped while the range increased.

 

[AlanSubie4Life]

When the car is parked or is sleeping the BMS recalculates the range and I often see the results such as below.
The percentage dropped while the range increased.

Are you sure that's what TeslaFi is saying? To me it looks like it is just providing the math for you - that it went from 56% to 57% while sitting, for a -1% change in energy. Of course, it is possible for % to decrease while energy increases...but requires a fairly large change in nominal full pack - 8 rated miles in this case (and I don't see that in your plots).

But honestly, I have no idea (I don't use TeslaFi so not familiar with the reporting details and formats - seeing more datapoints and correlating with what the car says would explain what is happening though). And it's not uncommon for the BMS estimate to increase when the car sits. I don't know exactly what the mechanism is (rebalancing or just re-estimating?), but it happens. Decay can also happen, repeatedly (even without any actual vampire drain of significance). And the direction can depend on the specific SoC.

 

[RS69]

Hello All

i booked a service appointment as my m3 2020 sr+ is only showing 219 at 100% charging, my WH/m is 256 lifetime with 13652 miles on the clock. I received the following from tesla

Hi there Mr. Your range concern has been looked into and an appointment is not needed. We have carried out various checks and have a document to send you if you could provide us with an email ? Thanks Tesla Service

any ideas

 

[AlanSubie4Life]

Hello All

i booked a service appointment as my m3 2020 sr+ is only showing 219 at 100% charging, my WH/m is 256 lifetime with 13652 miles on the clock. I received the following from tesla

Hi there Mr. Your range concern has been looked into and an appointment is not needed. We have carried out various checks and have a document to send you if you could provide us with an email ? Thanks Tesla Service

any ideas

You have only lost 12% of your capacity. This is fairly normal. A bit on the high side, but quite normal. Hopefully it will slow down for you. Nothing you need to do.

 

[wildguess]

Hello All

i booked a service appointment as my m3 2020 sr+ is only showing 219 at 100% charging, my WH/m is 256 lifetime with 13652 miles on the clock. I received the following from tesla

Hi there Mr. Your range concern has been looked into and an appointment is not needed. We have carried out various checks and have a document to send you if you could provide us with an email ? Thanks Tesla Service

any ideas

I got the message "It is normal" from Tesla when I booked a service appointment with 204 miles at 100%.

 

[KenC]

My only thought is that your low point, at around 30,000 miles, you said was Jan 20, which is mid-Winter, and your recovery at around 36,000 miles was in April, early-Spring. Teslafi and the app I run, Stats, use the SOC api that is temperature-affected.

Here's my data from Stats, overlaid with temperature, that shows how much the 3rd-party apps, like TeslaFi and Stats, using the temp-affected SOC api, show BMS range estimates that correlate with temp change:
View attachment 643246
Now, strangely, since Jan 24th, the temp and BMS range estimate no longer seem to be correlated. I did get a bunch of software updates in this time period, so I do wonder if something changed, whether Stats decided to use the other SOC api that isn't temp-affected, or whether Tesla changed something. Dunno, but mid-Winter I expect the BMS estimate to show 304-306miles, and I'm currently getting 309-313miles, what I would normally show mid-Summer. Strange.

Anyway, just wondering if you ran your BMS data vs ambient temps to see if there's any correlation. Yes, I know, Houston, but as you can see, even small temp changes affect the BMS range estimate that 3rd-party apps seem to use.

DM'd with the Stats developer today, and the odd datapoints from end of January where the estimated Range went up, ~310miles, in the middle of Winter, when in the past it had stayed low, 304 miles, is because he switched SOC apis.

Of course, the old data is the old data, and it fluctuates based upon ambient temps; but the new data from end of January is now temp-independent. That, explains the odd gap between temp and estimated range that one can see at the very rightmost part of my chart. Here's the Stats chart. Red arrow points at where the SOC api changed, and my estimated range went from low 300s to 310+. I thought it was odd, now I know why.

 

[AlanSubie4Life]

DM'd with the Stats developer today, and the odd datapoints from end of January where the estimated Range went up, ~310miles, in the middle of Winter, when in the past it had stayed low, 304 miles, is because he switched SOC apis.

Of course, the old data is the old data, and it fluctuates based upon ambient temps; but the new data from end of January is now temp-independent. That, explains the odd gap between temp and estimated range that one can see at the very rightmost part of my chart. Here's the Stats chart. Red arrow points at where the SOC api changed, and my estimated range went from low 300s to 310+. I thought it was odd, now I know why.
View attachment 644694

Still 310 miles, lol. Crazy.

 

[Sklith]

My estimated range has been all over the place. I'm pretty disappointed how low it's gotten, though.