Only 3% battery degradation on M3LR (E5D battery) after +3 years and 75.000 Km!

[zef3215]

Last night I run for the first time the build in Battery Health test from service mode on my +3 years old Tesla M3 Long Range (E5D battery) and +75.000 Km. I got home at around 21:20 with 5% SOC so I said this is a good moment to kick the test. I recorded data with Scan My Tesla during the test and here are some key moments:

• The car started to warm the battery using energy from the charger (from 13 Celsius – outside 2 degrees);
• At 21:40, the battery warming stopped with Cell temp medium showing 25 Celsius;
• Until, 23:15, the car did not went to sleep and consumed between 130-150W from the high voltage battery;
• At 23:15, the car started to charge the battery;
• At around 6:15 AM, the car stop charging and I got an alert on my phone that the car is charged to 100%.

I went to the car at 12:00 PM and the Battery Health test results are somewhat surprisingly good, indicating only 3% battery degradation!

I got the car in December 2020 and at 100% the car was showing 523Km of ideal range. In January 2021, I got an update that “boosted” the display range on my car to 534Km. Right now the displayed ideal range is bouncing between 507 and 510. Having said that, I was expecting that Tesla would use 534Km as a “reference” for max when was new but it looks like it is using the 523Km. Well, no matter which one Tesla is using, both numbers looks good to me.

What do you think and what is your experience with degradation?

If you want to know more about this car you can follow me here: https://www.youtube.com/c/ZEFElectric

 

[shahryaran]

Is the E5D NMC from LG?

 

[zef3215]

Is the E5D NMC from LG?

Yes, introduced on M3 end of 2020 (at least in Europe).

Note: I uploaded now also the photo with the test result

 

[Bouba]

Same battery....M3LR made in China 74.5 kWh LG...2021 but only 25,800 km...when new it showed 542 km EPA...over the next few months it’s range increased to about 553 km....but I still use 542 as my base for calculations. Right now my car has a range of 522 km (324 miles)...approximately 2.75% degradation.
However I have not used the Battery Health Test and I haven’t used any technique to try and regain range....just normal charging.
My car is kept in the South of France and it’s never been cold

 

[zef3215]

Same battery....M3LR made in China 74.5 kWh LG...2021 but only 25,800 km...when new it showed 542 km EPA...over the next few months it’s range increased to about 553 km....but I still use 542 as my base for calculations. Right now my car has a range of 522 km (324 miles)...approximately 2.75% degradation.
However I have not used the Battery Health Test and I haven’t used any technique to try and regain range....just normal charging.
My car is kept in the South of France and it’s never been cold

I doubt you have the exact same battery. Is your car made in US or in China?

 

[Bouba]

I doubt you have the exact same battery. Is your car made in US or in China?

Made in China

 

[zef3215]

Made in China

I suspect your battery is slightly bigger, still LG and same chemistry. I remember after I order/pick mine, there were all these made in China cars with slightly higher displayed range.

I keep here some info about battery types used in M3 arround that time: Tesla Model 3 Battery types

 

[Bouba]

I suspect your battery is slightly bigger, still LG and same chemistry. I remember after I order/pick mine, there were all these made in China cars with slightly higher displayed range.

I keep here some info about battery types used in M3 arround that time: Tesla Model 3 Battery types

Your photo is out of focus

 

[zef3215]

Your photo is out of focus

Which photo? From my initial post? If so, you need to click on it to display it on full resolution.

 

[Bouba]

Which photo? From my initial post? If so, you need to click on it to display it on full resolution.

Post #7 the photo isn’t in focus

 

[zef3215]

Post #7 the photo isn’t in focus

Is a link to a Google Photos album. If you follow that, you should be able to see multiple photos in good quality.

 

[Steve446]

Sounds good for that km and timeline. There are several ways of obtaining a good idea of your battery status. Regards the battery health check, there's some discussion on exactly how it works and the subsequent result you get. Refer the thread, "HV Battery Health Test Confusion" posts #10, 27 and 33 from @AlanSubie4Life. He also suggests using the energy screen method after a full charge. You mentioned that you also had SMT so you can use Full Pack When New and Nominal Full Pack to estimate current battery capacity. All these might comfort your result.

 

[etigro]

Last night I run for the first time the build in Battery Health test from service mode

Can you elaborate on how you can run that test ? I did not see anything like it while in Service Mode.
I am currently relying on Teslamate to log data (and calculate battery degradation) and it is giving me an 8% degradation which I find high (@5 years and 70K km).

 

[zef3215]

Sounds good for that km and timeline. There are several ways of obtaining a good idea of your battery status. Regards the battery health check, there's some discussion on exactly how it works and the subsequent result you get. Refer the thread, "HV Battery Health Test Confusion" posts #10, 27 and 33 from @AlanSubie4Life. He also suggests using the energy screen method after a full charge. You mentioned that you also had SMT so you can use Full Pack When New and Nominal Full Pack to estimate current battery capacity. All these might comfort your result.

Sounds good for that km and timeline. There are several ways of obtaining a good idea of your battery status. Regards the battery health check, there's some discussion on exactly how it works and the subsequent result you get. Refer the thread, "HV Battery Health Test Confusion" posts #10, 27 and 33 from @AlanSubie4Life. He also suggests using the energy screen method after a full charge. You mentioned that you also had SMT so you can use Full Pack When New and Nominal Full Pack to estimate current battery capacity. All these might comfort your result.

Hmm, SMT today:
Nominal full pack = 69,5kWh
Full pack when new = 74,5kWh
That will suggest a 6,7% degradation.

Following the consumption screen:
I just drove 77% (highway speed 120-150km/h) and consumed 51kWh. That will suggest 66,2kWh to which we need to add the buffer below zero (about 3,2kWh) so that will be very close to what SMT reports however, there is also so heat loss which does not show up on the numbers.

When I do the display range calculation will indicate either 3% (if working with 523 km when new) or 5% (if working with 534 km after the update that “boosted” the range).

I still wonder why would the build in battery health test show 97%!?

 

[zef3215]

Can you elaborate on how you can run that test ? I did not see anything like it while in Service Mode.
I am currently relying on Teslamate to log data (and calculate battery degradation) and it is giving me an 8% degradation which I find high (@5 years and 70K km).

When you are in the Service Mode you go to “High Voltage” -> “HV System” and over there you will see the last result (if it was ever run on the car) and have the option to run the test.

 

[etigro]

It is probably not available for all type of cars and/or battery. It is not there on my S. Too bad.

 

[Steve446]

Hmm, SMT today:
Nominal full pack = 69,5kWh
Full pack when new = 74,5kWh
That will suggest a 6,7% degradation.

Following the consumption screen:
I just drove 77% (highway speed 120-150km/h) and consumed 51kWh. That will suggest 66,2kWh to which we need to add the buffer below zero (about 3,2kWh) so that will be very close to what SMT reports however, there is also so heat loss which does not show up on the numbers.

When I do the display range calculation will indicate either 3% (if working with 523 km when new) or 5% (if working with 534 km after the update that “boosted” the range).

I still wonder why would the build in battery health test show 97%!?

Hmm - I think you just demonstrated how difficult it is to estimate your battery capacity with significant accuracy. It looks like your battery is an LG M48 like my car (and for @Bouba). You mention that your FPWN is 74.5 kWh (same as mine). That makes 1% battery, 0.74 kWh or thereabouts.

First off, purely as an example, depending on the accuracy of a specific type of data measurement (which are often subject to rounding), measurements that seem different could in reality be very similar. I refer to your 3% and 5% above - it would not take much of a measurement variation and then data rounding to make those practically the same.

Next, when did you take the SMT readings? Straight away or a few minutes after Bluetooth connection? Sometimes it takes a while for SMT to get a current value from the CAN bus and sometimes it will only do that if the car has been driven. It depends on the parameter, but, you could have errors there too.

I appreciate all that sounds a bit bla bla, but the example is rational.

I use NFP data over time in order to assess battery capacity, It appears good for +/- 0.5 to 1 kWh error on total capacity. I could comfort that data with the SMT CAC values (when they were working in SMT before last December!). The other ways of estimating capacity seem to give about a 1 kWh error as discussed in previous posts. On that basis I would be inclined to believe your NFP calculation of 6.7% (but that's my opinion only and happy to be called out). Logically that value would also depend on lifetime average SoC, average storage temperature and n° of charge cycles as per @AAKEE posts. In the end best to charge to 100% and drive to display 0% when it's moderately warm, avoiding phantom drain wherever possible, then you'll know for sure for the current battery capacity.

What I don't get is the result from the health test. The "HV Battery Health Test Confusion" talked around that without arriving at a conclusion. I wonder if it's actually measuring other parameters Tesla considers critical to a healthy pack - things like pack imbalance where a cell is significantly down on the others in the same module? There's a commercial post discussing this here

 

[nicksp]

I'm on my 3rd EV and don't pay much attention to charts and graphs anymore. I just drive. Yesterday my 18 M3LR went for 297 miles when I got to a charger. Drove between 65 and 75 mph with AC controlled manually. Can't be any happier.

 

[AAKEE]

Hmm, SMT today:
Nominal full pack = 69,5kWh
Full pack when new = 74,5kWh
That will suggest a 6,7% degradation.

Following the consumption screen:
I just drove 77% (highway speed 120-150km/h) and consumed 51kWh. That will suggest 66,2kWh to which we need to add the buffer below zero (about 3,2kWh) so that will be very close to what SMT reports however, there is also so heat loss which does not show up on the numbers.

69.5 x 0.955 = 66.3725 kWh between 100-0%, each percent 0.663kWh.

66.3725 x 77% = 51.1 kWh.

There do not need to be heat losses.
The Nominal Full Pack number reflects the energy the battery should be able to deliver. The battery is charged with more energy than the nominal remaining, so it should be able to deliver that number in electric energy and the heat is the exxcess energy it had stored.

The nominal remaining number can be delivered at a specific power or C-rate, for example 15kW or 0.2C. A higher C-rate or power would mean the losses are higher and the output lower.
So a relaxed drive, around the speed delivering the EPA range you could expect the batt to deliver the nominal remaining energy.
Higher load - more losses - less output.
Lower load - less losses - more output.

The values above havent been uncommon for me to see. I have often had clean matches of delivered energy and the change in nominal remaining.
Cold battery at winter and/or faster drives will set a heat loss that cause a delta between delivered and the nominal remaining change.

When I do the display range calculation will indicate either 3% (if working with 523 km when new) or 5% (if working with 534 km after the update that “boosted” the range).

The M3 LR had a charging constant of 137Wh/ km.
Each km is worth 131 Wh on the range at the batteri icon.
The new range with 74.5kWh would have been ca 543 km.

77% at 0.663 = 51.05 kWh
51100/131 = 390km used.

Fully charged your car should show 507km today (69.5kWh) if the 100% charge hit that number. I always seen ~ 0.2-0.7kWh more, so a few more miles is possible after a full charge.

I still wonder why would the build in battery health test show 97%!?

We have seen this more or less at any report of the service mode test.
I guess there is a reason we can access it, and a reason we know the code and also a reason for the number more or less always are higher than what we can calculate otherwise.
= Users worried get a blue lie ( the truth modified a little to make the owner happy).

Tesla would easily be able to calculate the real degradation

Edit: do the service mode test show capacity or only that health in percent?
Remember the part of low load = less losses and higher energy delivered?
The test use the motors to burn energy?
And this is done at a slow rate?

That’ll show better values than the real driving ones according to the explanationnin the beginning of the post.

 

[AAKEE]

What I don't get is the result from the health test. The "HV Battery Health Test Confusion" talked around that without arriving at a conclusion. I wonder if it's actually measuring other parameters Tesla considers critical to a healthy pack - things like pack imbalance where a cell is significantly down on the others in the same module? There's a commercial post discussing this here

The battery test drains the battery quite slow, right?
Se my post above about energy delivery vs battery load.

We will see better values on a slow discharge test than we see wehen really driving.
Bet Tesla was smart enough to use that fact to ”stow away a little degradation”.

The degradation test performed to se if the car is entitled to the 70% remaining warranty should be performed with the same load as the EPA test was made with.
Also, the initial energy should be not too far from the delevered energy in the EPA tests.