Tesla battery after 11k miles
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The owner of the first Model 3 to go over 100,000 miles says he has lost only 2.5% of his original 310 mile range. https://electrek.co/2019/10/21/tesla-model-3-100000-miles/
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nice! That's only a single datapoint, though.
My screenshot compares with the distribution obtained from thousands of cars.
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This is incorrect information. He miscalculated. He has a RWD that got its typical consumption constant changed with an update. This sentence here from electrec is particularly misinformative and inacurate
The update was pushed to all cars, but obviously earlier builds "never got" the 325 miles, because their batteries were degraded below that point so they actually saw 310 miles and thought, oh I never got that update...Whereas if they didn't get the update, their max would've been around 300 miles.
So his current typical range calculation with the newest update is using a newer typical consumption constant and therefore his degradation can (kind of) be measured from the 325miles point to about 5-7%, which is still pretty good if he abused the car that much. I wish he had an OBD II with ScanMyTesla to actually see how much kWh he has left.
2.5% is impossible after 100,000 miles - most cars will loose 2.5% in the first 10-15,000 miles. Mine has lost about 1.5kWh in the first 10,000 miles and judging by the estimate on the OP, he has lost around 2kWh, which is exactly 2.5% from the 77-77.5kWh when brand new. So no, 100,000 miles cars can't do 2.5% degradation, no matter what some blogers write.
Unfortunately you can't really measure degradation with TeslaFi, because of differences in typical range calculations and the way Tesla calculates the typical range and the % SOC shown on screen.
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It would be nice to see a real-energy degredation as @TeslaKiller points out. Empty the battery, then charge it up to measure capacity. Miles and estimates are just that, useless estimates.
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This is one way to measure it, but it has to be done on at least 11kW or 22kW charger to avoid any phantom drain. Since most new EV drivers are not familiar with the phantom drain and the car might sit for a longer period while charging, this could scew the results. Also, the kWh added number you see inside the car is not accurate - it also uses the typical range calculation.
The only real way to measure capacity is to charge to 100% and drive immediately from 100% to about 5% and write down the kWh used. Important, for the test to work you have to drive steady and around the typical consumption under energy - otherwise heat loss.
So the real test is to drive at about 60-65mph for about 300 miles on a single go and write down the kWh used in the car ("since last charge").
But I doubt he will be able to measure more than 70-71 usable kWh during that test. (75kWh - buffer of 3.5kWh)
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Agreed. Would also be useful to use a dummy load and trick the car into DC fast charging to connect the battery directly to the load. A waste of power, but a test is a test. With more data from the BMS could characterize the voltage curve at typical '5 hour drain' currents (similar to driving 300 miles at 60mph). DC charging and discharging would tell the whole story ignoring the AC charging option.
Couldn't agree more.
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I'm not denying that the software upgrade made his capacity loss seem less than it was. But lithium ion batteries experience the most loss early in their service life. This article has a number of capacity curves, and you see that the capacity loss slows down significantly as the battery ages. https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
This article doesn't talk about Tesla battery packs, which have specifically been designed for excellent thermal management and long life. It is not unexpected that you have already experienced the bulk of the battery capacity loss that you are going to see in the first 100,000 miles.
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First, there is nothing to support this claim from the data we have today. For what is worth, the battery degradation on the 3s with the data we have so far is actually historically a little bit more than the data from some of the most recent S and X.
We have seen, proven, data degradation of cars such as the one from Bjørn Nyland of about 5% in the first 40,000km. And I am yet to see a car with data below 2% after 20,000km(most are at 2.5% as OP's car)
So I wouldn't believe anything Musk tells you. From what I am seeing, the 3s have at least the same, if not more degradation.
Especially on the SR+ models, because of the low capacity and the buffer being relatively big in percentile - those owners will be in for a huge surprise down the road.
As for the rest of your sentence, yes, the biggest drop happens around the 20,30,000miles and after that the drop is more graduate, which fits perfectly to the article's expected 7% degradation after 100,000 according to my calculations. If he is at 7%, at that abuse, I think the battery held well.
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I have Model 3 dual motors with 13,564 miles (21,829 km) and charged to 100% this week, still showing 310 miles (Teslafi shows more precise 309.8 miles.) But your basic thesis is that I can't believe that, that my battery capacity has to have actually degraded by at least 2%?
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Well, what does this image proof? Nothing.
The actual math goes like this:
kWh total capacity/245*1000 = rated range.
The thing is, the cars that are shipped have anywhere between 77.5-78kWh. You might have gotten a good battery and the BMS estimates 78kWh at brand new. Using the above math
78/245*1000 = around 318-319 miles rated at brand new
But since Tesla voluntarily decided to "max" the displayed rated range to 310, you never "saw" those hidden miles displayed to you, but you have been using them since day 1. Same with the RWD LR update of 325m "that never came".
Now if you do the math and we assume you are at around 309m and not 310 or 497km
Now if we reverse that same math
309*245/1000 = 75,70kWh total.
So you think you have 0% degradation and somebody else liked it and thought the same, but the reality is that you already lost at least 1.5-2kWh and this is a real degradation of worse case 3% to about 2. something%
Also, change to KM and see if you get 499/500 as brand new (as it is rated) or 497km or something even lower and post the screenshot.
If you wanna do degradation calculation based on SoC% and rated range, which is 2%-4% inaccurate(more in my video), you should change to km and charge in km
I explain most of this math in this video:
There is also another video from another driver who has the same observations on his S
watch?v=gMjFQftk6WQ
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@Stats App I don't see the screen that you posted in my version of Stats App and I'm a beta tester. Is this a new graph on the 3rd screen that hasn't even been released to beta testers yet?
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It's not in the StatsApp which is why I asked if he is planing on incorporating it into the app. It's a separate app that he's charging $2.99 for...BatteryCompare. Honestly I don't care as much about paying for it as an in app purchase. I just don't need another app cluttering my iPhone...and how often would people actually use it?
Whats your charging habit like? 80%? 90%? How far down do you go? Do you plug in every night?
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Thanks for the info
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I do not plug in nightly, or even with any regularity. For the first 5 months of having the model 3, it was doing a lot of road trips and mostly supercharging, from 90%+ to <20%. I've charged to 100% about half a dozen times. Haven't been below 10% much. Past 6 months, have only been driving it about 500 miles/month, and more or less cycle between 70%-ish to 35%-ish depending on what I expect to need it for, charging 1-2 times a week. (Teslafi tells me I only charged it 5 times in October.) Sometimes I charge it to 90%, sometimes I only recharge to 50% if it is just going to be sitting for awhile.
I've done similar things with the model X, and it had pretty classic indicated range loss of about 5% between 6000 miles and 12,000 miles, but nothing (so far) after that. At 30,000 miles, it is rock solid at the same range it was at 12,000 miles.
The variability that different people report intrigues me. The difference between my 2 cars puzzles me. I don't pretend to know what matters. I don't attribute the current good range on my model 3 to any of my behaviors. About the only rule I live by is not to let it sit above 90% or below 20% charge.
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I think this is a good rule. What is your car reporting in KM not miles at 100%?
Just to add another datapoint, my LR RWD 3 is at around 14000 miles (11 months old). I charge my car to 80% almost every weekday and drive between 45-60 miles per day on weekdays, so I only every get down to around 60% regularly. It varies on weekends from <10 miles to >150 miles per day so I may charge only once on weekends by skipping the days where I don't drive more than 10-20 miles. I used to super charge on average 2 or 3 times a month until my free super charging ended, the exception was a 1000 mile road trip where I exclusively supe charged for 5 days straight. I've only every charged to 100% once and that was to see what my full capacity range is, and it wasn't during my road trip either.
All that said, my 100% charge is now at 302 miles, which is about a 7.0% decrease from 325 miles. My 80% range is around 240 miles, so it matches the 302 miles at 100% pretty accurately. I'm not terribly concerned because it doesn't really affect my daily driving, but thought I'd throw it out there if anyone reads this and sees a red flag in the charging/capacity of my car.
All that said, my 100% charge is now at 302 miles, which is about a 7.0% decrease from 325 miles. My 80% range is around 240 miles, so it matches the 302 miles at 100% pretty accurately. I'm not terribly concerned because it doesn't really affect my daily driving, but thought I'd throw it out there if anyone reads this and sees a red flag in the charging/capacity of my car.
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