> I've regularly wondered how much of the slow battery degradation in these car battery packs is "cheating".

Using the word "cheating" has a very negative valence, but it's not exactly a secret that EV batteries are not designed to use their full "raw" capacity. The manufacturer is quite clear that you should avoid charging to more than 80% on a regular basis as it will degrade the battery faster. What matters is not that the batteries are capable of some theoretical "raw" capacity but that the advertised capacity is correct, just like with SSDs. It doesn't strike me as cheating that SSDs have more capacity than what is advertised on the (proverbial) box.

I don't know the right word, scare quotes were to accommodate for that. If not cheating then at least misleading or avoiding disclosing the actual mechanics and degradation of the battery. To the tune of it might be possible a new car would actually have 50% more than the range it allows you to use to make it seem like the batteries degrade much slower than they do.

>The manufacturer is quite clear that you should avoid charging to more than 80% on a regular basis as it will degrade the battery faster.

This is one of the things that doesn't add up. If the article says you can drive a tesla 200,000 miles and still have a mid-80s percent of total battery capacity left, why are car manufacturers being so clear about charging patterns to "save" the battery? With the std deviation bars in the graph showing a pretty small distribution, it would seem charging behavior doesn't matter (of course there will be people who don't follow the guidelines and if so there should be an expected much wider distribution)

The facts from studying the mechanics of raw cells of earlier lithium chemistries, the advice from the vehicle manufacturers, and the data in this article do not add up.