I've heard around these forums that LTE will not drain a phone's battery any more than 3g on newer phones. I have a Samsung Galaxy S3 though and that seems not accurate in my case to the point where I almost dread LTE showing up because I'll be having to go on airplane mode within a couple hours.
Even when I go to a place with strong Sprint LTE signal with high data rates (e.g.; 20 mbps), my phone will only last a few hours at most before I am in the yellow. If I am on 3g though with that kind of signal and general use, I can generally last a day without charging.
Is the Samsung Galaxy S3 just not good at LTE battery life or is LTE simply a battery hog? I am hoping it is the former since I'm going to be upgrading soon.