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85d battery deteriorating

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My battery seems to be failing. 85d with 85k miles. Since buying the car used I have been good to the battery pack - limited supercharging and typically keeping in 20-70% charge range.

Did an experiment and ran pack low to 7% and then charged all the way up to 98%. Downloaded file from charger and pack only took 63.9 kw. That's total and must include some energy for pack warm/cool etc . . . This seems pretty bad. Also tried supercharging a couple times for a few minutes and capped below 50 kw. Any suggestions, should I bring it to a service center? Should I fight for pack replacement?
 
I gave up on Superchargers since June of this year, luckily we had no road-trips scheduled since then. From my experience it's a complete crapshoot. I would typically see charging speeds no higher than 60kW at V2 stalls, but would get the full 72kW at urban stalls; however, the charging times were longer than before because of the restriction of the taper.

This past weekend we took a trip up to San Luis Obispo and one charging session at a V2 stall gave us a charging rate of 127kW. I've never seen it so fast in our S85. I'm never sure if the slow SuC experience is due to the hardware of that specific SuC stall, the hardware on our S85, or the software limitation. I just hope for the best and prepare for the worst (a call to Tesla, AAA, and a rental car company).
 
Day to Day? Jeeze... how long is your commute?

Just over 200 miles return, with car sat all day. Even 100% charge in winter is too tight. I probably logged a lot of DC charging but just a 10 mins splash and dash in the evening, which was fine when I got 110kW. I might see a brief 90kW now if low enough but seems to prefer max of ~70kW. Week to week if we are pedantic.
 
Take it to 100% and leave it there for a few hours.

Charging to only 70% on a continual basis isn't the greatest for the battery pack. Doing it regularly isn't bad, but the battery does need to go to 100% periodically.
Interesting...i was under the impression from the multiple batter threads I’ve read that 70% SoC is ideal for battery longevity and minimizing degradation.
 
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Interesting...i was under the impression from the multiple batter threads I’ve read that 70% SoC is ideal for battery longevity and minimizing degradation.

70% is better for battery longevity. People are confusing calibration and balancing with longevity but you can also calibrate and balance by just cycling. I leave my SOC at ~70%. My range does 'degrade' but it's not real... it's just a calibration/balancing error. When I go on a road trip I get most of that back. Heavy cycling can help with balancing and calibration but it causes real degradation that cannot be restored.

So pick your poison. Real degradation or perceived degradation.
 
My battery seems to be failing. 85d with 85k miles.

Also tried supercharging a couple times for a few minutes and capped below 50 kw. Any suggestions, should I bring it to a service center? Should I fight for pack replacement?

I have a March 2015 S85D with 80,885 miles. The last time I full charged this summer, the range was 260mi. While some supercharger stations have recurring issues (Truckee) getting peak power, I still get 115kW at most superchargers if I arrive with less than 20% or so charge
 
I've documented some of the degradation and slow down at the supercharger. The way Tesla has crippled the old 85 battery is pretty devastating. My supercharging speed is about half of what it was. At the higher level its even worse.

I spend twice the time charging on road trips.

The most common misconceptionbis looking at the charge rate right after plugging in. It shoots up to over 120 kW now but starts dropping after a few seconds. The rate drops much faster than it used to. What really counts is how much time it takes to recharge a certain amount of energy or rated range. I documented that and it's much longer now. But people only look at the initial peak and think all is good.

Many 85 cars are affected by the battergate. Tesla has been stealing range from the car's. They do it slowly now so you don't notice it as much but it's affecting more and more cars. Mine lost 15 miles and it's still dropping.

They also implemented a much more aggressive cooling which takes up additional energy that is lost range. It's a combination of several things that crippls the 85 batteries in order for these to make safely passed the warranty period.

The original first adopters and true Tesla supporters are getting shafted.
 
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Not all 85's have the same problem. For sure, we are not seeing the same SuC rates as last year, but consumption and RM are about the same for many. In my case, I see a beneficial change under V10.

Possible some slower rates are due to wear and tear on the charging infrastructure.

Here are some results on my car on V9 vs V10...note that V10 has a higher and more sustained power at high SoC, such that Kw plus SoC percent is nearly constant, and only 10% less than before on V8 IIRC...
 

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70% is better for battery longevity. People are confusing calibration and balancing with longevity but you can also calibrate and balance by just cycling. I leave my SOC at ~70%. My range does 'degrade' but it's not real... it's just a calibration/balancing error. When I go on a road trip I get most of that back. Heavy cycling can help with balancing and calibration but it causes real degradation that cannot be restored.

So pick your poison. Real degradation or perceived degradation.
I've been charging all our Teslas to 90% every day and experienced very little degradation. The oldest S is a 4.5 year old P85D and, 90% charges to 225 on a warm day and 224 on colder days like today. 1.5 year old S75D coincidentally charges to the same miles at 90%. I think when each was new, 90% was 226 (I think, not 100% sure).
 
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I've been charging all our Teslas to 90% every day and experienced very little degradation. The oldest S is a 4.5 year old P85D and, 90% charges to 225 on a warm day and 224 on colder days like today. 1.5 year old S75D coincidentally charges to the same miles at 90%. I think when each was new, 90% was 226 (I think, not 100% sure).

Okay, so what is your kWh battery capacity on the P85D?
 
The way Tesla has crippled the old 85 battery is pretty devastating.
I’m wondering if there is different chemistry in the earlier 85Kwh battery than later production runs like mine that is a Nov 2015 build.

I haven’t seen the battery capacity or charging reductions to the extent others are experiencing. With 50k miles on the speed-o I’m still around 77kwh and 249 miles of rated range. Strange how this is not a universal issue for all of us.
 
I’m wondering if there is different chemistry in the earlier 85Kwh battery than later production runs like mine that is a Nov 2015 build.

I haven’t seen the battery capacity or charging reductions to the extent others are experiencing. With 50k miles on the speed-o I’m still around 77kwh and 249 miles of rated range. Strange how this is not a universal issue for all of us.
Congrats! You have not been impacted. Y'know there is something fishy about this. Why would only some of the early batteries be effected and others not? It may be because of the degradation from use and charging? It could be from the BMS managing temperatures. Etc. The only published chemistry change was when the 85kWh went to 90kWh, increasing 6% due to adding silicon to the anodes. So that doesn't effect us. There is so much more that Tesla is just not telling us. That really is the biggest part of this issue. Tesla not telling us what is going on and then reducing battery capacity and slowing SuC speeds.
 
Okay, so what is your kWh battery capacity on the P85D?
Just under 82KWh, like every other Tesla with "85 KWh battery" ever built (yes, welcome to Tesla marketing specs, not as bad as 691hp they advertised for P85D but still total BS). 77KWh of that is usable since there is a ~4KWh anti brick buffer. S75 has an actual 75KWh capacity and smaller anti-brick buffer, so ~73 usable KWh. The rated efficiency of the S75D is better than the performance motor, so the two end up having the same rated range (actually S75D has a slightly higher advertised rated range than P85D). In real life the P85D will go farther if driven the same (when for example we take both of them on a trip and ride together convoy style).
 
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Congrats! You have not been impacted. Y'know there is something fishy about this. Why would only some of the early batteries be effected and others not? It may be because of the degradation from use and charging? It could be from the BMS managing temperatures. Etc. The only published chemistry change was when the 85kWh went to 90kWh, increasing 6% due to adding silicon to the anodes. So that doesn't effect us. There is so much more that Tesla is just not telling us. That really is the biggest part of this issue. Tesla not telling us what is going on and then reducing battery capacity and slowing SuC speeds.
Elon applied agile continuous integration, continuous deployment methodology (developed for web applications development) to cars. He used to be proud how they improve the hardware in production every 2 weeks. "Fail fast" is the Silicon Valley motto. Who knows how many version of the battery are actually out there. They also could have experimented with different battery management strategies to determine the best one, and maybe some of the strategies ended up damaging the batteries. So they learned their lesson but it was cheaper to limit those damaged batteries than replace them. We'll never know, unless Tesla is forced to come clean. Of course it might also be possible that they don't have records of everything and people who left took the knowledge with them.
 
The question has to be asked whether this or similar "now we know" fixes will affect 100kWh cars and all Model 3s...with DC charging speeds ramping up will it push the batteries too much and a massive swathe of customers have a yr 4 negative experience?