First 10k miles Model Y Long Range battery degradation less than 2 miles

Hello everyone,

I benefited a lot from other posters in this forum, so thought I'd give back by sharing my personal experience. Earlier today I charged to 100% for the first time in months just in order to see what the actual range is rather than one extrapolated from lower states of charge. Yes, I know that even with this approach the reading can be off, but I surmise that if the reading is 328.14 or 328.48, the precise range likely rounds to 328.

Here's the historical chart from TeslaFi showing calculated range from December last year, 3 months after I took delivery of my Model 3 LR. Interestingly, the battery shows no incremental degradation throughout the entire period that we have data for.

Over the 9 months and 10k miles, about half of the charging was from 50 kW DCFC stations. About 10% was supercharging, and 40% was Level 2 charging. I typically charged to around 70%-90% then ran the battery down. A few times I did charge to over 90% immediately before a lot of driving. Whenever I left the car at rest for a few days or longer, I made sure it had around 60% battery or less. So even though I charged to high SoC's often, the car didn't spend much time at over 60% SoC. Also, it's been a long and cold winter in LA, so storage temperatures have been very favorable.

Because I have a long work commute, and because I don't use home charging, I think I have relatively deep charge-discharge cycles, probably around 50%. I'm sure after a lot more miles this will catch up to me, but for now it's quite clear that calendar aging plays a much larger role.

Happy to answer any questions about charging habits. Otherwise, I think I'm an example of how keeping a Tesla at a low SoC is very effective in minimizing battery degradation.

 

[zroger73]

I know many people think their car sleeps but they use their app all the time and it constantly wakes the car up if it’s within bluetooth range.

My iPhone XS Max is within Bluetooth range of my 2023 Model Y when I'm at home, but it does not keep the vehicle awake. The phone key shows up as a connected Bluetooth device, but not the vehicle. The vehicle will wake up if I open the Tesla app and when it does I hear the contactors cycle.

 

[AlanSubie4Life]

Since the road trip, I've had the car sleep at 38%, 20%, and 73% SoC. Rated range has continued to drop. I'm going to expand the SoC range for sleeps over the next few days and see if the BMS changes range readings.

View attachment 954829

Seems normal. Big steps like this in the BMS estimation are the norm rather than the exception. Rock solid for months then boom…either up or down.

Of course your pack has lost capacity at this point; that is just physical. The BMS is doing its best to find that answer!

Seems reasonable given the conditions to expect 2-3 percent at this point, taking you to about 76.5kWh minimum (depends on your pack’s actual initial capacity which may have been as high as 80kWh or more), which would be 320 miles (323-325 seems about right to me with some initial energy above the degradation threshold). So I’d expect the current estimate is a bit low, probably. But not way off.

Just keep that SOC below 55% or so if you can, when it is going to remain at or near that charge for more than a few hours. If convenient. If not, fill it up!

 

[johnny_cakes]

The sleeps were overnight, so varied between 7 hours and 17 hours. I didn't ask TeslaFi to put my Tesla to sleep, but it recorded these overnight sleeps.

I notice you had a bunch of charges to the top SoC range. I think I'm gonna charge to 100% at some point this week to see if that moves the needle.

Curious if you were able to recover your indicated capacity loss

 

[Hiline]

Curious if you were able to recover your indicated capacity loss

So I did charge to 99% and run the battery down to 4% with proper sleep at various states of charge along the way, then charged to 99% again. Both charges showed the same range as at the end of the road trip: 311 miles. I don't think I'm going to charge to the high 90's % again - just going to go back to my old charging habits so I don't degrade the battery too much just to correct the BMS. We'll see what happens as time goes on.

 

[johnny_cakes]

So I did charge to 99% and run the battery down to 4% with proper sleep at various states of charge along the way, then charged to 99% again. Both charges showed the same range as at the end of the road trip: 311 miles. I don't think I'm going to charge to the high 90's % again - just going to go back to my old charging habits so I don't degrade the battery too much just to correct the BMS. We'll see what happens as time goes on.

Thanks for the update. It feels like BMS calibration is more of an art than science. I immediately adopted the low SoC strategy (setting daily charge limit to 55%) when I bought my 2019 Model 3 back in January. Stated range was ~340km at that time. I charged to 100% a few months later and the stated range jumped to 346km for a few days, then I let is sit overnight at 5% and it cold soaked down to 0% SoC. The stated range dropped to 330km. It was only months later when my wife set the daily limit to 67% and forgot to bring it back down for over a week when the range jumped up to ~340km again. Now I've got the daily limit set to 55% again and stated range is slowly coming back down. Big mystery to me

Projected range at 100% SoC according to TeslaMate:

Projected range according to Tessie:

 

[Mateo83]

I'm down to 278 from 305 on the MYP after 10k.

 

[johnny_cakes]

I'm down to 278 from 305 on the MYP after 10k.

That's quite a bit for a car that's just over a year old. I hope the BMS calibrates and you recover the perceived loss in range soon.

 

[Mateo83]

That's quite a bit for a car that's just over a year old. I hope the BMS calibrates and you recover the perceived loss in range soon.

I hope so too, but fear its degradation. The range is pretty poor.

 

[Quickst]

It won’t balance cells unless it’s at 100%

Ive heard that when SoC hits 100% there can sometimes be >0Amps current flow on the charging app. Possibly indication rebalancing as some cells still letting amps in ??.
So don't stop until Amps = 0.?

Does we get the "Charging stop" indicator when 100% SoC is reached or when current flow = 0?

 

[zroger73]

When my MYLR reaches 100% (or any other charging limit), the charging currently decreases to 0 amps for several seconds then increases to >0 amps to match the current power demand (e.g., pumps, compressor, infotainment, accessories, etc.). As long as anything on the vehicle is awake, I don't think the charging current will stay at 0 while plugged in since the vehicle will use shore power to keep from discharging the battery.