These are all the appearances of James' bottle cap collection from the Kanto, Orange Islands, and Johto seasons that I can remember.
UPDATE: Added a few more episodes thanks to folks who have reblogged/commented on this
episode 73 "Bad to the Bone"
episode 96 "Meowth Rules!"
episode 123 "Spinarak Attack"
episode 157 "The Fortune Hunters"
episode 181 "A Ghost of a Chance"
episode 182 "From Ghost to Ghost"
episode 184 "All That Glitters!"
episode 205 "The Kecleon Caper"
episode 208 "Fight for the Light!"
episode 255 "Why? Wynaut!" (although it's really more of an allusion to his collection because it sounds like James didn't want to keep them)
episode 267 "Love, Pokémon Style" (I think they're being flattened into coin shapes? They call them "badges", but...)
Pokémon Chronicles episode 13 "Training Daze"
I can't help but notice that several of these episodes make it seem like James lost his entire collection and by the next time the collection appears he seems to have all of them back again.
