When do you "store" your vehicle? If you are talking anything less than a few months, that's not storing.
Science and researchers do not in general think of ”store”.
Batteries degrade from usage (cycles) and time (calendar aging). This is the approach from researchers and science.
Calendar aging actually happens all the time. Cycling during charging and discharhing.
For a user perspective we can think that calendar aging is the non operating - non cycling time, but in fact the batteries ahe from time when used as well.
The average car might do 15-20K km or 10-15K mi each year. That comes to about one hour discharging each day (comlon aversge speed sbout 50-55 kph over a year).
Charging, in europe we often use three pase up to 11kW, so about 1-2 hours average.
If you like to think that driving/charging do not cause calendar aging you still end up with 21 of 24h of non operating period each day.
So it do not matter how you would like to see it - calendar aging happens all the time or at least 87.5% of the time.
Forget the ”storage” thinking for your own car. The battery can not know if you just parked the car until tomorrow or next week or if you ”stored it” so it will degrade perfectly by the calendar aging schedule anyway.
Tesla says (in all EPA applications silce the behinning of time) that if battery packs is to be stored they should have 15-50% SOC.
The cells in the packs do not know they are ”stored” so they just decide to follow the calendar aging principles (where 15-50% is good, and beginning at 15% ensures it will not drop too low during a loooong storage period).
The summof the research tell us how batteries will behave in our cars. In fact 95% of all research reports are done in the context of electrical vehicles andcrefer to EV, EV usage like the common owner might use it.
Trying to circumnavigate the sum of the research is like staying that the earth is flat.
From research we
know quite much.
Its not wils guesses or rumors or myths, it is facts.
I think it even was possible to predict your batterys degradation and capacity despite not knowing more than the age of the car, roughly your charging habits and the ~climate where you live.
The reason for the calculation to hit wuite well was that the sum of research knows how batteries degrade.