Aww f** great. just tried the battery-change out on my M3 who wasn't saving nor starting the module at all. After buying 3 batteries (I'm an idiot for 4-fig numbers) I eventually got the old battery out. And what does it say on the back which you can only read if you remove the battery? "Li-Ion Rechargeable Battery". Now what? Is my M3 broke and the battery is/was fine or it was empty and the M3 couldn't fill it? Is there any sense in replacing the battery? If the M3 tries to charge the battery, I don't know what will happen (GBA exploding?). But if it was able to charge, why didn't charge it the old battery? If the M3 isn't capable of charging (anymore?), and the old battery was empty, is it usueful to replace the battery? So in a hurry: Is the Battery in a M3 normally a rechargeable one? Is the M3 recharging it? If my M3 doesn't start, how often it is a dead battery? How can I easily tell if that battery has any power left? Will the M3 explode if it tries to charge a normal battery? Thanks for help?