Lithium battery charge level for optimum longevity

someone rang for me?
Teslas are the only long-range EV, & now have that distinction for ~ a½ decade.


Reasonable advice? Consider historic data rather guru's imo. Even the youtube video above is just a reference to someone who the video publisher believes is 'the' ultimate go-to source. Duno .... he says the 'guru' is an atmosphere science/physics guy, rather then battery engineer (combo electrical/chemical). but ok, no harm - he doesn't contradict tesla recommendations , but says 70% .... that simply gets more specific than necessary, because there's no empirical data to say what the consequences are, if you don't abide by this guru's extra specificity.

the graph above represents a ton of owners that use logging equipment
(& continue to do so) in order to determine what kind of diminished capacity might be expected on the whole, long term. The # of owners logging in excess of over 200K EV miles continues to grow since the graph above was published months ago.
The data represents leadfoot owners, gentle/gingerly driving owners, hot weather owners, freezing weather owners, people who charge/discharge to the max frequently, owners that supercharge almost exclusively & some that never supercharge, paranoid owners that charge at home only ½way &/or only to ¾ full .... you name it - the whole shebang.
As Barney Fife used to say, "nothing to see here - move along! " .
IOW, its been known for quite some time - that best conditions are moderate weather, gentle charging/discharging, & primarily to somewhere in the mid-range, it all helps capacity longevity. Excellent or poor thermal management makes a huge variable too. A plug in or standard hybrid has the help of an ice to keep things in the middle too. Tesla owners can manually set maximum charge to any level of maximum capacity they want too, in order to help longevity too. Historically, all this info is already a given.
So lithium longevity? Short answer?
ymmv.
IMO, the nicest bit of data that one can glean from the graph - is that even after 200K miles - on average, owners with great thermal management & reasonable care can expect to not lose any more than 10% of their capacity. so if a long-range EV has the potential to go > 300 miles, somewhere past a decade of ownership, one can STILL expect > 270K miles of capacity.
What a coincidence! same thing if you'd owned a 2004 prius for > a decade now

hope that wasn't too verbose.
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Thanks. You forgot this.

 

Fawlooooow - meeeee.
At 6'-5" - back in the day - i have been affectionately called 'Lurch' , on more than one occasion .
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