Do Plaids really get slower over time? Performance loss?

[Mudassar]

Brooks from DragTimes posted a video 5 days ago of his 2021 Plaid racing a 2024 Plaid - it seems his Plaid has gotten slower over time. I am very curious about this. Both cars had the same SOC but he was getting walked on in the top-end. Sure, all the variables... driver weight, tire pressure, wheel weight, etc. but I'd like to understand if Plaids really DO face a loss in performance as they age? I've already searched through every possible thread on here, Reddit, YouTube, Twitter/X regarding the subject but it's still not clear...Is it true? Do Plaids face a loss of performance through the years? Or, could this be software related? I've heard some owners say their Plaids feel slower after a software update sometime in 2022. Has anyone else experienced this?

Yes, I understand the difference between getting used to the power and ACTUALLY losing power.

And before I face backlash for my curiosity - no, I don't race my Plaid on the drag strip. I've gone once or twice and had a blast. I understand this may be a trivial matter to some, but I'd love to just understand how it works and what the explanation could be for this phenomenon. Also, I know that others have experienced completely different results, such as Andrew from @teslaplaidchannel, who noticed the same exact results, or often faster E/Ts, after 1900+ 1/4mi time slips - wow! What gives?

tl;dr: does the Model S Plaid "lose power" (for lack of better words) or face a loss of performance as it ages? If so, how and why? What causes this?

 

[LoudMusic]

I'd expect all vehicles to get slower over time. It's just a function of the mechanical bits wearing out.

 

[AAKEE]

tl;dr: does the Model S Plaid "lose power" (for lack of better words) or face a loss of performance as it ages? If so, how and why? What causes this?

The internal resistance increases in the batteries over time.

In general Performance Teslas are limited by the battery power.

Power = Voltage x Current

So when the internal resistance increases the battery voltage sags more from the same load. As it is the voltage that drives current, the current will also be lower.
The end result is less power.

The internal resistance increase is higher the higher the SOC is.

This chart shows the increase rate of internal resistance depending on the SOC, and also temperature.
We can see that the internal resistance increases more the higher SOC we have.
The rate of the increase reduces relatively fast, but after one year the IR has increased by around 20% if the battery are at 80% SOC

I charge to 55% daily as this reduces the Calendar aging to around half the value of higher SOC. This also reduces the rate of the internal resistance increase by about 50% as well.
In the end I will have only half the power loss over time compared to if I had used the ”usual” 80%.


Source for the picture. Its a good read in many sspects.

 

[MN-MS100D]

Maybe go check out Tesla Plaid Channel because his car is just as fast after hundreds of drags.

 

[Izzyz28]

They typically get slower by 3-5 MPH and 1-2 tenths in the quarter as they age. Oh no.

 

[yerEVan]

Post 3 is probably what you’re looking for, post 4 is correct but didn’t read your original post in its entirety, post 5 hilarious.

 

[Sellout]

Post 3 is probably what you’re looking for, post 4 is correct but didn’t read your original post in its entirety, post 5 hilarious.

Fascinating to me that losing 3-5mph in the quarter is a joke. That’s quite a difference.

Sure, the only thing you can do about it is keep your average charge level low and/or move to a colder location to keep the average temperature low, but that level of performance drop is brutal.

Not that I’d really care if I had a Plaid, I’m more the type who just wants a fast street car rather than a racer anymore. I’ve been a racer in the past, just don’t care for the competition anymore.

 

[racerx2005]

I charge to 55% daily as this reduces the Calendar aging to around half the value of higher SOC. This also reduces the rate of the internal resistance increase by about 50% as well.
In the end I will have only half the power loss over time compared to if I had used the ”usual” 80%.

Interesting… I’ve been charging my 23 MSP to 70% … will lower to 55% just in case; losing “less” power is mostly welcome; worst case my “100%” charge will be closer to what’s advertised, which would help when selling the car by 2027 (buyers for used EV’s are most worried about the “100%” battery charge than anything else).

 

[Izzyz28]

Fascinating to me that losing 3-5mph in the quarter is a joke. That’s quite a difference.

Sure, the only thing you can do about it is keep your average charge level low and/or move to a colder location to keep the average temperature low, but that level of performance drop is brutal.

Not that I’d really care if I had a Plaid, I’m more the type who just wants a fast street car rather than a racer anymore. I’ve been a racer in the past, just don’t care for the competition anymore.

If you had a Plaid, you would never feel the power drop, we're talking a ~3% drop in performance after 40k+ miles. Even in the video, it was worth about a car length over the 1/4 mile, extremely negligible.

 

[tstafford]

Interesting… I’ve been charging my 23 MSP to 70% … will lower to 55% just in case; losing “less” power is mostly welcome; worst case my “100%” charge will be closer to what’s advertised, which would help when selling the car by 2027 (buyers for used EV’s are most worried about the “100%” battery charge than anything else).

I generally charge to 50% for this reason. I think it will probably help to prevent degradation. For sure matters more in high heat.

 

[Krash]

The cars have always had different limits on performance at different speeds. First there is a torque limit. Then a power limit. Then a battery limit that in the past was greatly influenced by back EMF.

Since the plaid introduction, that third curve is much improved but still dependent on state of charge (SOC) and general battery age.

The drag strip result variation you are describing, on average, should be entirely from this third region. Meaning that an old and new car should behave exactly the same until the older battery power output would dip below the max power setting, and then the older car would gradually fall behind.

So if you are seeing differences in the 0-60 and the battery is still being limited in max power, I’m curious as to why, since the car shouldn’t hit this third region until after 60 mph.

Here is what the old school graphs looked like.

 

[AAKEE]

Interesting… I’ve been charging my 23 MSP to 70% … will lower to 55% just in case; losing “less” power is mostly welcome; worst case my “100%” charge will be closer to what’s advertised, which would help when selling the car by 2027 (buyers for used EV’s are most worried about the “100%” battery charge than anything else).

And as the degradation will be cut in half, your car would show the best range of similar cars, at least if you start when the car is new.

My MSP ’23 march build (23K km) did show full range until a couple of weeks ago, now i have ~ 635km/ 395miles with the 19” selected and 598km/347mi with 21” selected (have double wheel sets.
(Lost a couple of kWh after having full power fun at a closed airport at two separate times )

 

[bkcyk]

We ALL get slower over time. lol It's funny how people generally lose sight of the fact that the automobile is a consumable. Nothing is forever.

I do appreciate the ego based d!q measuring contest going on here. It'd be cool to think performance doesn't degrade one iota as it ages, but we're talking about a low to mid 9 second car for the duration of your ownership period. Only 1st world goobers fret about such trivial figures in the grand scheme of automotive things.

The more clear and present negative for me is power output being so dependent on SOC. I enjoy driving my Plaid at 70-80% much more so than at 10-20% because the power loss is noticeable. A brand new Plaid at 20% will get walked by its 50K mile older brother at 90%.

90%+ power is really where it's at, but it's so fleeting. Per Tesla, I only charge to 80% on the daily.

This is where ICE truly shines for me, but then everything the other side of a Bugatti Chiron is getting run past in our humble toaster of a sedan.

 

[AAKEE]

I think it it good that that video was made.

I have been stating this since I got my first Tesla 3.5 years back as one of the reasons to not use more SOC than needed for everyday driving etc.

For the battery / SOC part I do not know how the planned future solid state batts will behave. Hopefully less internal resistance and better power delivery.
But for the current ones (Panasonic NCR18650) we would need a larger battery with more cells to deliver more power.

I recently had fun at a closed airport strip I have access to, two occasions with several quarter mile drags with Dragy and some up to top speed runs, and lost about 1kWh nominal full pack each time.
(Before I had very low degradation, like almost none compared to the usual top value).
After some tests, it is clear that the BMS is not off so the real capacity did drop like this.

It is clear that the power level (battery power up to ~ 8-9C is also gard on the battery. I think Brooks (?) at Dragtimes has a lot of quarter mile runs. Probably that caused some of the power loss.
So, calendar aging probably is not responsible for all power loss, but some or most likely most of it.
The 37K mils itself, probably not a noticable part of it.

 

[Mudassar]

Maybe go check out Tesla Plaid Channel because his car is just as fast after hundreds of drags.

I have, and I even mentioned that in my post... Andrew and I are friends. And he's done over 1900 passes now, far more than "hundreds"

 

[Mudassar]

If you had a Plaid, you would never feel the power drop, we're talking a ~3% drop in performance after 40k+ miles. Even in the video, it was worth about a car length over the 1/4 mile, extremely negligible.

Except people have felt and seen the power drop, and in competitive drag racing those fractions are everything -- it's the difference between winning and losing...

 

[Mudassar]

Hey, folks - I have figured it out!

Turns out Brooks abused his battery pretty badly. Earlier this month, he charged his Plaid to 100% SOC and stored it in an enclosed trailer before traveling across Florida with it for competitive drag races.

Yes, that's right - two full days trapped in an enclosed trailer in the brutal July heat in Florida, at 100% SOC... I'm confident that this was the reason his car performed so poorly on the top-end. What an asinine thing to do.

Very misleading video without this crucial bit of information...

Thanks everyone for your responses (except for the sarcastic ones).

 

[Ostrichsak]

OH MY GOD, THE HORROR! Glad you figured it out, I'm hopeful you can sleep at night now that the mystery is solved.

Well but he's friends with him. He just forgot. Or something.

Imagine being worried about your 9-second quarter mile car being tenths slower after years of driving it so your "solution" is to keep it at 50% (or less) SoC the entire time making it substantially slower every time you drive it.

Why buy a Plaid? What are we even doing here?

 

[turns2stone]

Well but he's friends with him. He just forgot. Or something.

Imagine being worried about your 9-second quarter mile car being tenths slower after years of driving it so your "solution" is to keep it at 50% (or less) SoC the entire time making it substantially slower every time you drive it.

Why buy a Plaid? What are we even doing here?

Any measurements of actual wheel power at different SoC rates? On my current M3 Performance, it certainly feels slower on my butt dyno once SoC falls below 70%

 

[GatorMeat]

The internal resistance increases in the batteries over time.

In general Performance Teslas are limited by the battery power.

Power = Voltage x Current

So when the internal resistance increases the battery voltage sags more from the same load. As it is the voltage that drives current, the current will also be lower.
The end result is less power.

The internal resistance increase is higher the higher the SOC is.

This chart shows the increase rate of internal resistance depending on the SOC, and also temperature.
We can see that the internal resistance increases more the higher SOC we have.
The rate of the increase reduces relatively fast, but after one year the IR has increased by around 20% if the battery are at 80% SOC
View attachment 1063981


I charge to 55% daily as this reduces the Calendar aging to around half the value of higher SOC. This also reduces the rate of the internal resistance increase by about 50% as well.
In the end I will have only half the power loss over time compared to if I had used the ”usual” 80%.


Source for the picture. Its a good read in many sspects.

I think the NMC batteries have much less degradation according to the Jeff Dahn research (video on YouTube)
I assume all newer S/X have these better batteries?