Torch :: BB 9800 Randomly Turns Off

It turns off whenever I try to use the browser or the camera without fail and other random times. In these instances, it doesn't not show a battery drained shutting down warning. It has to be charging in order for it to reboot, but once it does the battery reads that it is 100% charged. Being on a phone call will drain a full battery in less than 5 mins, and it will flash the empty battery and say radio too low for handset use or whatever. In this case, I can charge it and it goes through the usual process where the light turns yellow and the bar slowly fills up. If I do a battery pull at this time, it restarts fully charged. The time it lasts out of the wall is anywhere from 5 mins-1 hour. I have no 3rd party applications and I did a complete device reset last month due to the same problems. I don't know much about software, but it says everything is up to date.