Delete The Facebook App on Your Phone
I cannot tell you how much battery life this has saved me since I have deleted the app. Before deleting the app I tried everything from removing notifications to killing the app process on the phone. Nothing seemed to stop the app from running in the background on my Android phone. I deleted the app and phone lasts probably 50% longer even on Wifi mode.
I will continue to use Facebook but on my iPad only as a solution. I am disappointed that Facebook and Google Android have not resolved this problem as I see this problem posted all over the internet. I am curious if others using an iPhone have found similar problems with their battery life? Please post in the comments below.