If you're talking about issues with battery life after the 5.1.1 update, I've been having the same problems.
I don't want to turn this into an iphone discussion thread, but I tried a fix just last night that seems to be working better so far.
Battery life was the least of the problems. Mute switch and volume buttons stopped worked, when in speakerphone mode, the mic didn't work, with incoming calls, there was no ringtone, just vibrating and calls would drop constantly. It seemed almost like a hardware issue, but it all started as soon as I installed the update.
It's a non-issue now, as I took it to Gamestop yesterday and get $235 in credit for it and now I'm working on flipping that credit to Best Buy. A little extra work, but far better than the $150 in credit Best Buy offered for it.