Why is 70% a end of life threshold? Considering that most major models are sold with configurations where the entry level begins under 70% compared to the "Long Range" model, clearly 70% is a perfectly fine level of battery for some users.
I myself have a 11 year old Nissan Leaf with pretty significant battery degradation (the guessometer says 70 mi range but I wouldn't count on more than 35-40) and it's fine for probably 95% of my driving.
If I were to buy an electric car with 300-350 miles of range today, I could easily see myself finding a ton of value in it in 20 or even 30 years. It's still more range than my current one! Lol.
Battery degradation is non-linear, and when it reaches a certain point of degradation it can be become unstable. This has lead to 80% being the traditionally considered point for EOL of a Li-Ion pack. However, this is a rule of thumb and the data is evolving with the technology.
"When the battery degrades to a certain point, for instance, if a battery can only retain 80% of its initial capacity,9, 10, 11 the battery should be retired to ensure the safety and reliability of the battery-powered systems."
I myself have a 11 year old Nissan Leaf with pretty significant battery degradation (the guessometer says 70 mi range but I wouldn't count on more than 35-40) and it's fine for probably 95% of my driving.
If I were to buy an electric car with 300-350 miles of range today, I could easily see myself finding a ton of value in it in 20 or even 30 years. It's still more range than my current one! Lol.