When did Dawn start to keep Piplup out of his pokeball?

Question

Dawn kept Piplup out of his pokeball for the majority of the seasons but I want to know when did she start and what is the episode's name?

Answer 1

Having run off from the lab in a dispute with Chimchar, Dawn finds Piplup trapped in a web and helps it out. Piplup & Dawn grew a close bond very quickly. Piplup can be described as a brat, but it truely tries its best in battles, despite the fact that its not the most powerful Pokémon. Dawn tends to let Piplup stay out of its Pokéball but does keep it in sometimes

Obtained in episode: Following a Maiden Voyage!