I haven't seen my GB Micro charger in a long while (I wonder where it is?) so I wasn't sure about that. Well, since it's a 100-240v charger I really dunno how OP proceeded to fry it.Thats not really true for the Game Boy Micro. It will work with 110-240v as long as you use the correct charger for your country.
Or be safe and use a USB Charger.
Then it must be obvious that this was just a case of battery Dead-On-Arrival. Just changing the battery will suffice.