/diy/ - Do It Yourself

So I have this small chinese music player, it works fine and its pretty convenient so I don't want to change it. But like with a lot modern electronics the battery goes to shit. But in this case is not entirely solded is just glued to the back and connected with a small connector (sorry I don't know the name) , since I wanted to change but couldn't find a direct replacement I was thinking about changing it for a cellphone one like one of those BL-5C old nokia batteries since it seems similar on size and voltage. But I just don't want to add some hot glue to the connectors and call it a day, I want to make so I can remove the batteries and exchange them easily since the BL-5C are pretty common and cheap. I was thinking about salvaging an old battery holder from a phone but it I wanted to know if anyone have done something similar, before fucking it up.