The first-generation Nissan Leaf was a car that only an owner could love. It had bug eyes for headlights, the body of a Bulbasaur, a toy-like startup sound, and a large plastic nub in the center console that you moved like an air hockey paddle to put the Leaf in drive or reverse. I was one of those owners, and while I swooned at the 2018 redesign, I still only had eyes for my first-gen Leaf.
But if you really wanted to know if the battery was viable, especially if a few bars were missing, you would need to get physical access and connect a Bluetooth OBD-II reader in combination with the handy-dandy LeafSpy app for iPhone or Android. If your own Leaf has a battery out of warranty, then you could try a third-party service that retrofits newer packs from donor Leafs that can enable longer range.