Featured Hyundai Ioniq6 Tops 361 miles EPA and 140MPGe (4.15mi/kWh)

You claimed :

People are just replying that age is a component in the degrading of Lithium batteries.

 

These charging curves are calculated from multiple users charging and operating their cars under different factors. The graphs include the individual data points. They show that the real world degradation of Li-ion in EVs(one of the graphs in my link was for Leafs) is following what is predicted from lab work. There is a rapid capacity loss in the first year or two, then it levels off to a near zero rate. Eventually, years and hundreds of kms later, the battery will enter a final phase of rapid capacity loss, but there isn't any real world data showing that yet.

The curve is a general trend. No one is claiming every battery will follow it.

The Model 3 with LFP has only been on sale for a couple years outside of China. There was the Coda EV years before, but it sold in low numbers. If you want a similar data set for LFP EVs now, you'll have to ask users in China for it. Or look up info on EV buses.

 

Age is certainly a factor, but age and mileage are strongly correlated, with most people driving between 10,000–15,000 miles a year. How the battery is stored also determines how it ages. Store it with 100% charge, and it may not last for five years even if you never drive the EV.

 

The data is statistics, and it averages out the charging habits.

If you read the paper you linked, the shape of the curve is determined by the competition and interaction between SEI (solid–electrolyte interface) formation and lithium-metal plating on the anode. The initial fast stage is dominated by SEI formation, but lithium-metal plating dominates later. However, faster charging results in faster lithium-metal plating, which will make the curve more linear through the charge/discharge cycles.

 

Thus why I called it a general trend.

How does knowing this help a person looking to buy a new car? Do they need to know what is physically happening inside an engine cylinder to know not to use octane lower than recommended?

I think regular fast charging can reduce the battery capacity is more common knowledge than the degradation curve.

This thread tangent started because you questioned @bwilson4web comment above a plateau in capacity loss here,

We've shown this general capacity loss trend wasn't something he pulled out of his nice person. Yet you seem to be searching for the exemptions that make the curve not so.

 

He said, he has reached a "plateau," which means the battery degradation has stopped. I said "more or less linear with the number of cycles." Why are you still playing this "gotcha" game?

The Tesla data below shows that the curve is almost perfectly linear after 20,000 miles. I don't see a "plateau" at other linked curves either. I don't care what happens during the break-in period, which is the first 20,000 miles that SEI formation reduces the capacity a lot faster. @bwilson4web has way passed 20,000 miles.

Be careful when you use this curve for Model 3. Model S has a 50% higher range, which means that the Model 3 battery will degrade 50% faster, as it is the number of charge/discharge cycle that matters, not the number of miles driven. Moreover, I am guessing that the deeper charge/discharge cycles increase the degradation rate. The smaller the battery, the shorter the life you will get out of it.



https://maartensteinbuch.com/2015/01/24/tesla-model-s-battery-degradation-data/

 

This is he said,

Plateau was being used colloquially. There was no graph or mathematic functions within his post. There is also a statement of expected length to this plateau. He never claimed degradation stopped.

I think others are caring less about what you have to say here.

The graph covers hundred of thousands of miles. It, and the user generated ones, include early models of the car. In the past, the Model S had 60, 70, and 75 kWh sized packs, which is the capacity range of the Model 3.

 

plateau: a region of little or no change in a graphic representation (source: merriam-webster.com)

@bwilson4web never uses terms colloquially. Look at the graph above. There is no plateau—end of story.

 

This study didn't seem to notice the SEI-formation region (initial faster capacity drop)—not to say that it is not there. It is fairly linear with miles driven.

Interestingly, they also found no correlation with battery age and battery capacity, unlike some claimed here.

http://www.pluginamerica.org/surveys/batteries/tesla-roadster/PIA-Roadster-Battery-Study.pdf
(right-click—save as—keep)

 

That is a very small sample size. Also, where they discuss capacity loss over time they say:

 

As for the Model S, there's even a handful of 40's out there.
Actually they were 60s but software limited until &/or if you coughed up the unlock fee.
Tesla Model S 40kwh plus supercharger enabled - No Longer Available | Tesla Motors Club
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