alt Hacker NewsIsn't this old news? I remember reading about 7yo teslas used exclusively in cold climates (Norway, Finland, etc) and they found the same thing: batteries held on much better than even the manufacturer expected. And those were often 1st gen cars, which you could expect to have teething issues.
It was at the time one of the main reasons the 2nd hand markets in those countries were pretty healthy and saw a lot of movement of used cars.
Some of the early models - either the Chevvy or Nissan Leaf - had battery packs which would degrade very quickly. This was causes by the charging system which seemed designed to destroy them.
The expectation in the EV fan world was that modern (> 2019) battery packs were very likely to retain 80% of their charge for well over the time anyone expected with the drop to 80% itself taking most of the car's expected lifetime. This was because the standard extrapolations ignored improvements in charging algorithms and that real-world usages were expected to be better for the battery than the models.
Another prediction we made is that range under cold (or very hot) weather would be significantly reduced and that seems to be the case too.