18 Months: I must be doing something wrong

[Fresnel]

Today I came out to my car with the passenger window half down (on its own). Second time it's happened, in the second week of ownership.

It was raining so part of the door and seat got quite wet.

I'm pretty sure that's happened to me too but I wasn't really sure that I didn't leave the window down so I ignored it.

 

[holmgang]

I'm pretty sure that's happened to me too but I wasn't really sure that I didn't leave the window down so I ignored it.

First time I thought the same. Second time I suspected the car.

You had a passenger? I did both times. I think it might be bouncing back down as safety-measure, as if it caught a finger on its way back up (when closing the door).

It's been cold as hell so my passengers weren't rolling it down on their own

 

[Fresnel]

First time I thought the same. Second time I suspected the car.

You had a passenger? I did both times. I think it might be bouncing back down as safety-measure, as if it caught a finger on its way back up (when closing the door).

It's been cold as hell so my passengers weren't rolling it down on their own

Yeah i think it was after having a passenger but not totally sure.

 

[AlanSubie4Life]

Watch this

You're talking about battery degradation which yeah... Still happens and is un avoidable. But there is a difference between battery degradation and rebalancing the battery.

This specific video does not seem to show that charging the battery to 90% repeatedly will restore the range - it sounds like Tesla reset it. I wonder how that car is doing today? It's also from a year ago so seems pretty conceivable that their software & BMS was a bit more buggy back then.

 

[SageBrush]

I just see no evidence to date that the numerous examples of 5-10% capacity loss on Model 3 batteries is not real.

Has that been corrected for battery temperature differences ?

 

[AlanSubie4Life]

Has that been corrected for battery temperature differences ?

Yes. Obviously have to be a little careful in winter time to watch for the outliers, and I don't pay too close attention to the TeslaFi data for this reason, especially in reports from cold climates. But there are a lot of cars in California where the temperatures are not in the range where you would see a significant change in range due to temperature, yet there are many examples which display the 5-10% reduction in range.

You can also use the Tesla app and swap between distance and energy display and if you use that % and rated miles it appears it will extrapolate to your actual 100% rated range even in cold conditions (but I don't have any experience with this, so that is hearsay).

Anyway, this was supposed to be a positive thread! The car is great, and I too have not had any problems (other than cosmetic issues which I resolved myself) in the 14 months I've had the car. I'm at 300 rated miles out of 310 (which is about 5.5% degradation from new most likely (not 3.3%)).

 

[SageBrush]

in the 14 months I've had the car. I'm at 300 rated miles out of 310 (which is about 5% degradation from new most likely (not 3.3%)).

My 20 month old car started out with 312 rated miles, jumped to 315 after the famed software update, and is now 312 miles the last time I checked about a month ago.
I'll eventually get to some point that I can point to battery degradation rather than noise or calibration. Eventually

Addendum: I just checked my car and calculated the range as rated miles/% remaining at 29% SoC and the battery in snowflake zone (probably 20-30F). Worked out to 307 rated miles. I'll now charge up to 95% and then recalculate the range. See ya in about 5 hours

 

[AlanSubie4Life]

My 20 month old car started out with 312 rated miles, jumped to 315 after the famed software update, and is now 312 miles.
I'll eventually get to some point that I can point to degradation rather than noise or calibration. Eventually

So you're at about the same as me - about 4-6.5% (312rmi*234Wh/rmi/78kWh) loss of capacity from new. I go back and forth on this and often slip (see above), but I try to call it "loss of capacity" rather than degradation. I'm hopeful that at least a portion of what people are seeing is simply something that may be recoverable at some point. But the longer it persists the less likely that is. On the other hand, the longer I hold at 5% loss of capacity the better off things are, as I'm probably through the initial period of rapid loss of capacity (it definitely seems the fastest at first, though the first 2kWh of loss of capacity appear to be hidden so that's presumably why people usually start by seeing "no loss" of range for the first few months).

 

[CharleyBC]

Take it in. That is something I've seen reported before.

It can also be a user error. I know of what I speak, since I did it. Upon exiting the car, it is very easy for the driver to unwittingly press one of the window buttons. For me, it turned out it was where I was instinctively placing my hand as I climbed out when in tighter quarters. I had to retrain myself, and the problem went away.

You may in fact have a defect, but this is at least a possibility.

 

[crackers8199]

Has that been corrected for battery temperature differences ?

at what temp would i expect to see a decreased number due to temperature rather than degradation? i'm in so cal, it does get cold here at night (into the 30s occasionally) but during the day i'm in the 60s-70s consistently. i would expect the temp has to be low for a certain time period before one would notice a lower reading due to temp, no?

 

[SageBrush]

at what temp would i expect to see a decreased number due to temperature rather than degradation? i'm in so cal, it does get cold here at night (into the 30s occasionally) but during the day i'm in the 60s-70s consistently. i would expect the temp has to be low for a certain time period before one would notice a lower reading due to temp, no?

No firm numbers to offer but you could calculate rated range in the AM after a cool night and then again after a day's use and higher temperatures.

I'm going for a similar result and test by charging up the car and then recalculating range

 

[AlanSubie4Life]

i'm in so cal, it does get cold here at night (into the 30s occasionally) but during the day i'm in the 60s-70s consistently. i would expect the temp has to be low for a certain time period before one would notice a lower reading due to temp, no?

I've seen things start to change when the outside temperature drops below 40 degrees (around 35 degrees). However, when the car has been cold-soaked to 50 degrees, I've never noticed any significant effect. It definitely does need to be cold soaked. If you've been driving the car on the freeway, charging it up fast, etc., in Lake Elsinore on a sunny day, you should have no reduction due to temperature. But you should only believe your numbers if you're extrapolating from something close to 90%.

 

[crackers8199]

I've seen things start to change when the outside temperature drops below 40 degrees (around 35 degrees). However, when the car has been cold-soaked to 50 degrees, I've never noticed any significant effect. It definitely does need to be cold soaked. If you've been driving the car on the freeway, charging it up fast, etc., in Lake Elsinore on a sunny day, you should have no reduction due to temperature. But you should only believe your numbers if you're extrapolating from something close to 90%.

i guess it's possible that i'm not driving it enough to ever warm it up. i work from home, so the car sits for the overwhelming majority of the day...on average i probably only drive 30-40 miles total to run errands at night, if that. weekends we go on longer trips and i drive much more, but the car sits most of the time during the week.

 

[AlanSubie4Life]

guess it's possible that i'm not driving it enough to ever warm it up.

I think it's very unlikely to be cold-soaked if it sits in the sun or a garage all day, even with the "chilly" recent temperatures. You might see some difference between early morning and after a full day in the sun though.

 

[KenC]

at what temp would i expect to see a decreased number due to temperature rather than degradation? i'm in so cal, it does get cold here at night (into the 30s occasionally) but during the day i'm in the 60s-70s consistently. i would expect the temp has to be low for a certain time period before one would notice a lower reading due to temp, no?

My temp, entered manually, and Rated Range data from Stats, over the last 12 months. If you look at the solid lines, the moving averages, it looks like as soon as temps drop below 60F, the Rated Range drops. We've seen others from warmer states, like Arizona show range drops correlated with temperature.

 

[crackers8199]

I think it's very unlikely to be cold-soaked if it sits in the sun or a garage all day, even with the "chilly" recent temperatures. You might see some difference between early morning and after a full day in the sun though.

it's in a garage during the day...i guess we'll see where charging to 90 takes us. i changed the limit the other day from 80 to 90.

 

[CharleyBC]

My temp, entered manually, and Rated Range data from Stats, over the last 12 months. If you look at the solid lines, the moving averages, it looks like as soon as temps drop below 60F, the Rated Range drops. We've seen others from warmer states, like Arizona show range drops correlated with temperature.
View attachment 501601

Looks like a correlation to me!

 

[AlanSubie4Life]

My temp, entered manually, and Rated Range data from Stats, over the last 12 months. If you look at the solid lines, the moving averages, it looks like as soon as temps drop below 60F, the Rated Range drops. We've seen others from warmer states, like Arizona show range drops correlated with temperature.
View attachment 501601

But if you use the Tesla app you won't see this, right (due to the difference in the SoC reporting used)? (I'm asking - I honestly have no idea since I've only ever seen the effect of temperature once, on a road trip - my car is kept in a garage at home and the ancient furnace loses about 20% of its heat to the garage, and I charge at work so it stays warm basically all the time.)

 

[KenC]

But if you use the Tesla app you won't see this, right (due to the difference in the SoC reporting used)? (I'm asking - I honestly have no idea since I've only ever seen the effect of temperature once, on a road trip - my car is kept in a garage at home and the ancient furnace loses about 20% of its heat to the garage, and I charge at work so it stays warm basically all the time.)

Yes, that's what I believe. When I see an anomalous Rated Range number in Stats, I check the Tesla app or the car. Using the figures from the car or the Tesla app, I do the math and my range is always between 308 and 312 miles. The 3rd-party apps like Stats are pulling the usable SOC API number, which seems to be affected by temp. You'll know it, when you get a blue snowflake day, and see the Stats Rated Range show a really low figure, like in the 280s.

Here you can see Stats showing SOC at 62%, when the Tesla app shows SOC at 57% and part of that is a blue snowflake, so it's actually even less. If you do the math, take the "Rated Range" of 176 miles, and divide by 62%, and you get 284 miles. That's what Stats will show in its Battery Health chart. Bt, the Tesla app shows my real battery SOC is 57%. Divide that into 176miles, and you get 309miles. Interestingly, the Rated Range number of 176 miles is the same as what the Tesla will show, it's just the SOC percent of 62 that is mismatched.

And, you can see the 284 mile dot below. That is an error, based upon the above.

Whether TeslaFi does the same, I don't know, but it also seems to show temperature-correlated rated range data.

 

[SageBrush]

So you're at about the same as me - about 4-6.5% (312rmi*234Wh/rmi/78kWh) loss of capacity from new. I go back and forth on this and often slip (see above), but I try to call it "loss of capacity" rather than degradation. I'm hopeful that at least a portion of what people are seeing is simply something that may be recoverable at some point. But the longer it persists the less likely that is. On the other hand, the longer I hold at 5% loss of capacity the better off things are, as I'm probably through the initial period of rapid loss of capacity (it definitely seems the fastest at first, though the first 2kWh of loss of capacity appear to be hidden so that's presumably why people usually start by seeing "no loss" of range for the first few months).

Your interp is as valid as any other reasonable one although it implies that I had the loss of capacity from day #1 which is unexplained.

There is a mountain of data from the Model S/X that up to ~ 5% loss of capacity occurs in the first year and then further loss is very gradual. If my car follows that path or better I'll be one happy camper.

Aside: I forgot to check my car's range after I charged up yesterday so I'm pre-heating the car now, will drive it this morning, and then calculate range.