You can use an OBD2 adapter and a free scan app to see battery capacity. Also others have seen labels on the battery indicating the size. But I think the range is just reducing due to driving history
Sun run probably has your charger. I don’t recall any dealer actually supplying the pro chargerHappy to report that upon resetting the trip records in the truck the DTE jumped to 304 miles, which is about what I expected given the winters in Hood River are fairly chilly.
One additional wrinkle I'm still working out with the dealership, apparently the Pro Charger which comes with the ER F-150 was removed from the vehicle during its service as a mannequin. They haven't figured out where it went yet but it's listed as standard equipment for these so hopefully they'll do the right thing and find it (or a replacement) without my having to kick up a stink.