8% degradation after 9k miles, wtf?

[Chewy986]

Hello everyone!

So, I read a lot about proper battery maintenance (or so I thought), but I’m sitting on 8% degradation after 5 months and 9k miles… which sounds like way higher than most people experience and is pretty worrisome.

I charge my battery to 80% everyday as soon as I get home from work. I drive about 80 miles round trip and use around 30% of the battery daily, so when I get home it’s around 50%. I have never charged it above 85% and have been down to 17% only once and very briefly. I charge with my 220v 50a garage plug. I have never supercharged.

Based on the above fact pattern I expected to be in really good shape, yet my results are so far sub par.

I did buy the acceleration boost but mostly drive on the highway and rarely use it. I typically cruise 70-80mph which may be part or the problem. I live in Houston which is a hot climate for the battery and I generally have the AC on pretty high. I suppose the hot environment mixed with AC load and 80mph cruising speed is a bit taxing but I haven’t heard much discussion on it.

Any advice on how I might curb this degradation? Did I get a lemon?

Today I read 57% battery yielding 170miles for a 298mi capacity (or about 8.5% degradation vs new). I drive a model Y LR which is quoted at 326mi new)

 

[acebufer]

Hello everyone!

So, I read a lot about proper battery maintenance (or so I thought), but I’m sitting on 8% degradation after 5 months and 9k miles… which sounds like way higher than most people experience and is pretty worrisome.

I charge my battery to 80% everyday as soon as I get home from work. I drive about 80 miles round trip and use around 30% of the battery daily, so when I get home it’s around 50%. I have never charged it above 85% and have been down to 17% only once and very briefly. I charge with my 220v 50a garage plug. I have never supercharged.

Based on the above fact pattern I expected to be in really good shape, yet my results are so far sub par.

I did buy the acceleration boost but mostly drive on the highway and rarely use it. I typically cruise 70-80mph which may be part or the problem. I live in Houston which is a hot climate for the battery and I generally have the AC on pretty high. I suppose the hot environment mixed with AC load and 80mph cruising speed is a bit taxing but I haven’t heard much discussion on it.

Any advice on how I might curb this degradation? Did I get a lemon?

Today I read 57% battery yielding 170miles for a 298mi capacity (or about 8.5% degradation vs new). I drive a model Y LR which is quoted at 326mi new)

Exact same here chewy, 4 months and 4k miles in, I'm 8.5% down on my MYP. I suppose it's bc I'm in TX and garage is hot, but will try some of these suggestions about varying the SoC and allowing deep sleep and see what happens.

 

[AAKEE]

Exact same here chewy, 4 months and 4k miles in, I'm 8.5% down on my MYP. I suppose it's bc I'm in TX and garage is hot, but will try some of these suggestions about varying the SoC and allowing deep sleep and see what happens.

Varying the SOC does only help with the range indication. The battery itself is not helped. If the car is 4 mounts and have been at high SOC during the most part of hot summer you probably have some true degradation that can not be wiped with BMS calibration( because if it calibrates to the correct capacity you will have some loss already).

My M3P is 10 months 25K Km/ 15.5K mi and I have just starting to see a difference in range, about 504km from 507-508km when new.
1. I live in a colder climate then most other.
2. I have the charging set to complete the charge just before driving away.
3. I use a low SOC range, charge to 55% and use down to 25-35%. The car stand with 25-35% during the night until it charges just in time before driving.

I have charged full whenever needed(some 10 times or a little more). I have about 15% of the miles done by Supercharging.

I am positive its possible to affect the degradation by using smart charging scedules.

 

[jcanoe]

You must be on an older version of the app as the new one doesn’t have that feature anymore.

It is still there. You have to first change the battery icon to display miles (or km) instead of % state of charge by tapping on the number value to the left of the battery icon on the Tesla vehicle's screen or else under Display options. Then when you slide the charging limit slider all the way to the right you will see the estimated range at 100% state of charge. (Don't forget to set the slider back to your preferred charging limit.) Tap the battery icon display to switch from miles (or km) back to % state of charge.

 

[TomServo]

I have a question, unless you charge to 100% then drive the car to empty at about 50 mph (to average the EPA Rated Line on the Energy App or about 245 wh/mi) and record the actual miles driven and kHw consumed aren't these displayed numbers folks are obsession over just raw calculations and not based on ACTUAL values?

We had a term in the Air Force called Planned vs Actual aka PVA seems this discussion falls into that category.

 

[AAKEE]

I have a question, unless you charge to 100% then drive the car to empty at about 50 mph (to average the EPA Rated Line on the Energy App or about 245 wh/mi) and record the actual miles driven and kHw consumed aren't these displayed numbers folks are obsession over just raw calculations and not based on ACTUAL values?

We had a term in the Air Force called Planned vs Actual aka PVA seems this discussion falls into that category.

Yes, thats true.

The BMS tries to estimate the battery capacity but it is sometimes a bit off due to charging scedules etc.
Actions to get more range shown on the batteri range meter doesnt change the real range.

I do not think you need to drive with the EPA-consumption speed. If you charge full and drive until the car stops without driving too hard(causes more heatloss in the battery) you can see the amount of energy used and compare that to the nominal full, or the known normal capacity. In the best of all worlds you also did this test when the car was new, so you can compare the results.

 

[Chewy986]

I actually scheduled a service with Tesla, via the app of course, for this very topic with the hopes they would text me or call me to discuss it. They actually called me 10 days later and said to discharge it to 10% wait 1.5 hours then charge at home to 100% and wait 1.5 hours to drive. I should do this monthly to exercise the battery and the miles / % battery will go back up. He said the % battery / miles to empty are based on many variables such as temp, previous driving habits etc.. He went on to tell me that the 10 days since I requested the service were used to look at my history, charging habits, speeds driven etc. and the numbers / % are just a snapshot in time and they were well below average of other MYs. We have since done the 10%-100% and indeed the miles to empty went up 5.

Very helpful. The previous driving habits could be key. Does that mean because I drive lead footed that my estimated range went down but not necessarily the kwh capacity of the battery?

 

[Chewy986]

I actually scheduled a service with Tesla, via the app of course, for this very topic with the hopes they would text me or call me to discuss it. They actually called me 10 days later and said to discharge it to 10% wait 1.5 hours then charge at home to 100% and wait 1.5 hours to drive. I should do this monthly to exercise the battery and the miles / % battery will go back up. He said the % battery / miles to empty are based on many variables such as temp, previous driving habits etc.. He went on to tell me that the 10 days since I requested the service were used to look at my history, charging habits, speeds driven etc. and the numbers / % are just a snapshot in time and they were well below average of other MYs. We have since done the 10%-100% and indeed the miles to empty went up 5.

Possibly the most useful post so far, very interesting. So because I drive lead footed it may be saying that I have less estimated range, but still may have something lose to 82 kwh of capacity?

 

[Chewy986]

2021 MY LR here. Just over 5k miles, car is 9 months old. 299 mi range @ 100%, just measured today.
299 / 326 = 92%, or 8% degradation after 5k miles.

It's been steadily decreasing every few month from 326 (new) -> 312 -> 308 -> 299 (now). I've been using Teslamate to keep track of the degradation (unfortunately, not since brand new). But the trend is clear:

I already reached out to Tesla when degradation hit 5% (~308 mi) last month, and Tesla HQ at Fremont did remote diagnostics. They recommended to charge to 100% often and sleep often to let the BMS re-calibrate. They also just change to display % and don't worry about the miles. Finally, they also said the usual "it's just an estimate based on driving speed, temp, elevation, hvac, blah, blah", which I don't buy (e.g. it's a Guess-o-meter), but whatever.

I will create another Tesla service visit once the degradation hits > 10% (290 mi or less indicated at 100%). FYI, my car never sleeps due to Sentry Mode being on 24/7/365, so it is possible that the BMS is totally messed up. But unfortunately I can't charge to 100% often or let the car sleep because apartment dweller.

What makes you think the driving habits factor is bs?

 

[Chewy986]

Exact same here chewy, 4 months and 4k miles in, I'm 8.5% down on my MYP. I suppose it's bc I'm in TX and garage is hot, but will try some of these suggestions about varying the SoC and allowing deep sleep and see what happens.

I’ve tried and it hasn’t helped. The driving habits thing is interesting. Bc it’s hot down here, we blast the ac’s and drive 80mph it sounds like it may be adjusting to reflect that we should expect lower miles of range for a given SoC. If true, it could mean our batteries are totally fine.

 

[cgell]

What makes you think the driving habits factor is bs?

Your driving style does not change the displayed estimated range. From Tesla’s website - “Displayed range in your Tesla is adapted based on fixed EPA test data, not your personal driving patterns.”

 

[mswlogo]

I’ve tried and it hasn’t helped. The driving habits thing is interesting. Bc it’s hot down here, we blast the ac’s and drive 80mph it sounds like it may be adjusting to reflect that we should expect lower miles of range for a given SoC. If true, it could mean our batteries are totally fine.

Don’t confuse degradation and estimated efficiency. The battery meter never factors in driving efficiency. When folks talk about driving habits and degradation they are referring to permanent capacity loss. And if you started to drive more efficiently it will not come back.

Average SOC over time is what matters most when it come to degradation.

 

[FloridaSun]

Here is another update on my MY.. It appears as the weather is getting cooler (not cold here in Florida but not as hot as in summer) I ended up with more capacity reduction and after 15100 miles, I'm at 312 mile range @100%

 

[lyrebird]

One thing I want to bring up is that, while your car has been driven for 5k miles (just saying), the battery may have been used much more than that due to AC/Heat usage, perhaps 7k or more. In EV, everything runs on battery.

I assume Tesla's downgrade experiment must have kept everything else to minimum.

 

[TerranCaz]

I'm at 10,800 miles on my 2021 MYP. I have a max range of 285 miles on the 21" wheels, down from originally being 303. I charge to 80% and it's almost entirely been done with supercharging as it's not possible to DC charge at my complex in the Bay Area. About 95% of the time my car sits at the 30-60% SOC range with sentry mode off. Ouch. Could be worse, but we'll see. Definitely going to be difficult to continue to use as a snowboarding vehicle if range drops this fast.

 

[brkaus]

At least mine is better than 3 other cars…

 

[Chewy986]

At least mine is better than 3 other cars…

View attachment 733521

Ah man, I’m the worst

 

[kishkaru]

2021 MY LR here. Just over 5k miles, car is 9 months old. 299 mi range @ 100%, just measured today.
299 / 326 = 92%, or 8% degradation after 5k miles.

It's been steadily decreasing every few month from 326 (new) -> 312 -> 308 -> 299 (now). I've been using Teslamate to keep track of the degradation (unfortunately, not since brand new). But the trend is clear:

I already reached out to Tesla when degradation hit 5% (~308 mi) last month, and Tesla HQ at Fremont did remote diagnostics. They recommended to charge to 100% often and sleep often to let the BMS re-calibrate. They also just change to display % and don't worry about the miles. Finally, they also said the usual "it's just an estimate based on driving speed, temp, elevation, hvac, blah, blah", which I don't buy (e.g. it's a Guess-o-meter), but whatever.

I will create another Tesla service visit once the degradation hits > 10% (290 mi or less indicated at 100%). FYI, my car never sleeps due to Sentry Mode being on 24/7/365, so it is possible that the BMS is totally messed up. But unfortunately I can't charge to 100% often or let the car sleep because apartment dweller.

Great news! After charging to 100% regularly for a few weeks, and keeping Sentry Mode disabled (let the car sleep), my projected range has now bounced back up to 312 mi at 100%. 312 mi is what I had 6 months ago. It even went back up high as 316 mi for a few days, but is now settling down at 312 mi steady. So the BMS is definitely learning after the calibration.

Assuming 312 mi is my real rated range, that's 312 / 326 = 95.7%, or 4.3% degradation after 8k miles.

 

[mikepatel3596]

Hello everyone!

So, I read a lot about proper battery maintenance (or so I thought), but I’m sitting on 8% degradation after 5 months and 9k miles… which sounds like way higher than most people experience and is pretty worrisome.

I charge my battery to 80% everyday as soon as I get home from work. I drive about 80 miles round trip and use around 30% of the battery daily, so when I get home it’s around 50%. I have never charged it above 85% and have been down to 17% only once and very briefly. I charge with my 220v 50a garage plug. I have never supercharged.

Based on the above fact pattern I expected to be in really good shape, yet my results are so far sub par.

I did buy the acceleration boost but mostly drive on the highway and rarely use it. I typically cruise 70-80mph which may be part or the problem. I live in Houston which is a hot climate for the battery and I generally have the AC on pretty high. I suppose the hot environment mixed with AC load and 80mph cruising speed is a bit taxing but I haven’t heard much discussion on it.

Any advice on how I might curb this degradation? Did I get a lemon?

Today I read 57% battery yielding 170miles for a 298mi capacity (or about 8.5% degradation vs new). I drive a model Y LR which is quoted at 326mi new)

I am in the same boat, I purchase my new AWD LR Model Y on Dec 29th 2020 and after 8500 miles I am at full change 295.

 

[mikepatel3596]

Great news! After charging to 100% regularly for a few weeks, and keeping Sentry Mode disabled (let the car sleep), my projected range has now bounced back up to 312 mi at 100%. 312 mi is what I had 6 months ago. It even went back up high as 316 mi for a few days, but is now settling down at 312 mi steady. So the BMS is definitely learning after the calibration.

View attachment 733539

Assuming 312 mi is my real rated range, that's 312 / 326 = 95.7%, or 4.3% degradation after 8k miles.

Thanks for sharing this, may I will try it out.

 

[mattnis]

My Model Y was delivered in June 2020. As best I can determine the degradation of the battery in my Model Y after 14 months is between 9% and 10%. I've read of degradation in the first year of between 5% and 10%, even 12%. This is one reason to always purchase the largest capacity battery if you have a choice of Standard Range and Long Range. Another reason is the lower efficiency and range in cold weather.

They should throw out the rated range.
That is the range when it's new and drops by 10% very very quickly.