Ok, just had this problem. Phone died at school plugged into my car charger for 30 minutes to get home. Plugged it in at home. Me and the wife got ready for bed and I read a book for a while. All-in-all about 4 hours on a charger. Unplugged it from the wall and into my computer searching Blackl to see if I had to buy a new phone. had been trying soft reboot for the previous 4 hours. And as it is plugged into the computer it started for me at 5% battery life from 4 hours of charging on and off. This thing needs a car battery to kick start it in the morning, eh?
Died right after I posted this. :-(... Maybe I'll give it a day to recharge...?