For me, they are the same thing. Example: My mandarin epi is listed as a Pochette Cles or Key and Change holder in the catalog. I believe one pronunciation is French and the other is in English. Please correct me if I am wrong.
There are differences. LV calls all key chains Cles but not all key chains have a change holder on them. Miroir cles comes to mind - it is just a metal tag with a chain.