I am having serious battery usage issues as well. I have to charge the S5 half way through the day without really using the phone at all, more if I actually need to use it. I have been watching the power consumption and it is cell standby, Android OS, and Android system that are draining the battery (an average of 64%, combined, in a day).
Before the Lollipop update my S5 would easily last a day even with moderate usage without having to charge it.
I'm having THE same issue!!! I've posted (below) in other forums trying to get some help. If I get anything out of it, I'll be sure to pass it along,
Any HELP, suggestions are greatly appreciated!
This is the recommendation I got from @galaxyclass. I just did it... I'll see how it goes!!
>> Duplicate post removed by Verizon Moderator to comply with the Verizon Wireless Terms of Service See Re: s5 lollipop update and draining the battery and slowing my phone down? <<