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3.0 Battery Longevity

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Well, reading back a bit in this thread, and based on my very limited knowledge about this stuff, it looks like I have a real problem with my battery. Here's the background. Any help / suggestions greatly appreciated.

First, I must mention that the Green Machine lives in a plane hangar about 30 miles from home, and the plane itself is out of service for an extended period, so it gets fairly limited service. I drove it San Diego to Santa Barbara and back back in August, and it seemed fine at the time, but as I approached Santa Barbara the screen said it had about 30 miles left, when it suddenly lost power. I managed to get off the freeway, and parked, but after I turned it off and back on, it now gave warnings about having a dangerously low state of charge. I got towed to the local Tesla service center, and left it plugged in there overnight, and everything seemed fine. Drove back later that week with a charging stop at a hotel in LA somewhere, put it back in the hangar with a low but non-dangerous state of charge, plugged in, and forgot it for a month or so. When I next went out, intending to take it for a drive, I discovered that it had never really charged up. It looks like either the GFCI had tripped or maybe a circuit breaker tripped, the GFCI head on the cable needs to be re-set every time either way. I made sure it was charging before I left. Came back a month or so later to the same situation, so I figured it must have tripped the circuit breaker when someone else on the same circuit must have used a high-current device or something. I dropped the charge current to 12A, came back the next day and it was still charging (standard mode), but that gave me confidence.

So today, beautiful weather, decided to take it for a drive. Everything looked fine at the start, the only warning was the ever-present TPMS error. But it felt sluggish. I drove it about 10 miles east, then took a back road up a long steep hill (to Crest, for anyone local to San Diego). As I started to go up the hill at full go-pedal, the car slowed to about 50mph, and the power meter was reading about 50kW. Gradually that dropped to 40kW and 40mph, so as soon as I could do a u-turn I did. Going back down the hill, if I floored it, I could see 100kW on the meter for a short time. I headed back to the hangar just in case. Experimenting on a safe, flat road, I found that starting from stopped and planting my foot, the power meter peaked at 1bout 100kW, but over a period of just a few seconds dropped to 75, 70, and flattened at about 60-65kW.

I parked and took photos of all the various battery-related screens, see below. I suspect that either the battery is seriously out of balance, or some cells are sour, or both. :-( But I'm not good at diagnosing stuff like this, hence asking for opinions. In the meantime I put it back on to do a range charge over night, and will go out again tomorrow to drive it down off max charge, and can report back. From reading back I can see that the CAC is terrible, and it's out of balance, but maybe others have other insights too.

Here are the photos:
 

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Power output limiting for ESS is often due to low battery SOC, high/low Temps, or lowest brick voltage, for which I don't see on your photos.
Next up would be to look at Motor temp, and PEM temp on the screens next time you drive when it has lower kw output.
It did not report any power limiting in effect, and I did look at all the temps and they were all in the green. It was a fairly short drive, all things considered.
 
Thanks for the advice/help. On Sunday, I set the car to charge in range mode, THEN got out and plugged it in, forgetting that opening the charge port reset it to standard mode. Bah. So on Monday I took a short drive, realized what had happened, and when I returned I plugged it in and then set to range mode charge. Going out again tomorrow.
 
My "Gen 2" 3.0 battery was installed Aug 2021, with a CAC of 209.93
Just 50 miles later it was down to 208.58, but stayed close to there for a while.
A year later, Aug 2022 & 2847 miles, it was 200.26
Two years later, Aug 15, 2023 and 5,768 miles, it was 194.20
Now, after 33 months & 6100 miles, my CAC is 193.78

Haven't done a full range charge in a while, but may for the upcoming Tesla Takeover (now X Takeover) trip. Clearly I need to be driving it more!
 
My "Gen 2" 3.0 battery was installed Aug 2021, with a CAC of 209.93
Just 50 miles later it was down to 208.58, but stayed close to there for a while.
A year later, Aug 2022 & 2847 miles, it was 200.26
Two years later, Aug 15, 2023 and 5,768 miles, it was 194.20
Now, after 33 months & 6100 miles, my CAC is 193.78

Haven't done a full range charge in a while, but may for the upcoming Tesla Takeover (now X Takeover) trip. Clearly I need to be driving it more!
Hmmm... So bring out the proverbial envelope back for scribbles...

In about 3 years you lost about 17 CAC AH, or about 6 AH / year. I've had my original-ESS car for a bit over 9 years, starting with a CAC of about 142.6, so at 6 AH/year, I should be down to well under 100. Instead I'm at 126.9 (1.7 ah/yr).

I dearly hope what you're seeing is just the initial drop, but after 3 years...? Still, at that rate it will take you about 10 years to get to where I am now. Not too bad when you look at it that way, I suppose.
 
In about 3 years you lost about 17 CAC AH, or about 6 AH / year. I've had my original-ESS car for a bit over 9 years, starting with a CAC of about 142.6, so at 6 AH/year, I should be down to well under 100. Instead I'm at 126.9 (1.7 ah/yr).
I don't know the science behind the behavior, but I would think the loss is also related to initial capacity, so percentage really. Like 6AH/80 versus 1.7/53 or something.


Still, at that rate it will take you about 10 years to get to where I am now. Not too bad when you look at it that way, I suppose.
And in 10 years you'll be even lower. Will we cross at some point further down the road?

At any rate, yeah not ideal but while I had been delaying my upgrade as long as possible, I finally decided to go ahead given:
1) Tesla could stop doing upgrades, even ones with deposits down, at any time.
2) Charging on road trips is getting worse, not better, for non Fast Charge enabled vehicles like Roadster.
3) I'm not getting any younger. My getting out of car groans get louder every year.
 
I’m considering buying a 2.5 with a totally bricked battery. With everyone’s experience is it worthwhile getting the 3.0 battery? Is it the same as the R80? I think it’s the only option now. It won’t be my daily driver so should I be concerned about longevity of the battery? Thx!!
 
I’m considering buying a 2.5 with a totally bricked battery. With everyone’s experience is it worthwhile getting the 3.0 battery? Is it the same as the R80? I think it’s the only option now. It won’t be my daily driver so should I be concerned about longevity of the battery? Thx!!
I would be concerned that there is no guarantee that Tesla will actually sell you a new 3.0 battery.
 
Is there a basis for this statement? Tesla have been actively selling and installing the latest R80 packs consistently for the past 3 years and counting with no plans to stop anytime soon.
I am not a Roadster owner and I have never tried to order a new Roadster pack, but I could swear that I have heard stories of people being turned down when they tried to buy one. Maybe I'm imagining it???

The point of my post was to have the prospective buyer look into it before buying a known bricked Roadster. Knowing the actual price that Tesla would charge today would also be good information to have.
 
We posted this last week

———

With even further headcount cuts in store, not hard to connect the dots on the future of the R80 packs when Tesla’a flagship Superchargers are being spun off.

Even less comforting considering people on this forum and their families may be affected

——-

quite aside from our own work on developing a lightweight replacement pack for the Roadster, we are decidedly more bearish on the R80

Tesla’s Supercharging Network is a flagship throughout the automotive industry. Of course, there are plenty of credible reasons to spin off the operations, and their real estate holdings and acquisition.

Relative to Tesla’s Supercharging operations however, the R80s are mere rounding error. A stroke of the pen away.

All will be revealed…
 

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