Apparently it's not necessary to remove the battery, but try at least (I'm curious).
The battery was stuck (too much glue) and the plastic tab didn't help, and I ripped it...
So I use the plastic opening tool on the other side to remove really gently the battery, it was really really stucked with the glue... Now I'll know when I'll need to change it.
I put a little piece of tape to repair the plastic tab for the next time.
For the other part of the guide, it was a piece of cake and I'm a bad bad handyman :)
Thanks for the guide!
Lorsqu'il en aura reçu, il pourra afficher un graphique de sa réputation au fil du temps.
Voici un aperçu de ce à quoi ressemble ce graphique :
Aucun point de réputation obtenu pour l'instant.