I’m definitely no battery engineer, so correct me if I’m wrong, but… wouldn’t a 100-mile-range battery pack have a shorter life span than a 200-mile pack under the same usage since its charge/discharge cycles would be deeper in terms of %, and possibly more frequent because of the reduced range?
Yes, this is kind of true. But how you use the battery is also important. If you frequently DC fast charge your pack, it will wear out significantly faster than using Level 1 (120V AC) or Level 2 (240V AC) charging. This is because DCFC pushes the boundaries of how much current the battery can safely take in order to reduce the amount of time it takes to charge the car. It's a balancing act between customer acceptability and limiting battery degradation.