Battery life drain?

[Labhras]

Hi all,
recently I've been having problems with my battery life with too much drain, so I recalibrated it. At first it was all good, the first two or three charges had pretty great battery life, and I usually didn't let it go below 15-20%.
Today for the first time I found in the battery section
- screen - 34%
- Android System - 15%
- Android OS - 11%
- Wi-Fi - 6%
- Device idle - 5%

after barely using the phone. It's weird since it's the first time Android System and OS appeared with such percentages. I have my phone on wifi, gps on but with power saving option. Power saving is of course on, but I barely used the phone in all this time.
I don't even have the classic battery hog also know as Facebook installed.
What do you think it's going on here?

 

[belodion]

There are things going on in the background, probably. In fact, the stats look fairly normal to me, though to make sense of battery stats you do have to take the time that they cover into consideration. If Android OS or one of the main system apps seems to be using too much battery, a Power Off and Restart will sometimes fix it.
To get a better idea of whether your battery usage is normal, check them at the end of the day, before you come to recharge - and incidentally it's better not to discharge the battery much below about 40% if you want to keep your battery healthy. The screen-on time and brightness should be noted, as well as the signal strength for that period.

Posted via the Android Central App

 

[Labhras]

I'm almost always on Wi-Fi, at home and in class - save from when I'm outside with no wifi on. I deactivated the LTE because I didn't have a great signal and it kept jumping between that and 3g. I'm on 3g, with usually very good H+, sometimes H.
I used to have screen brightness on auto, but I realized that unless I'm outside with a sunny day it's not required, so I have mine at almost minimum.
I already did a restart for a wakelock that happened when restarting the phone while plugged in.
The problem is that Android OS and Kernel have suddenly started consuming 14-15% each of the battery when before they were almost nonexistent.
I try to charge it when it's around 20-25%, but it depends on the day and whether I have access to a charger or not.
I have installed GSam Battery Monitor and these are the screenshots for the first charge. I barely used my phone, I charged it in the evening, checked couple of tweets and messages every hour or so, but then I left it alone since I was sleeping.
I included the wakelock screenshot - there are some that are apparently eating at my battery.

Do you think a system cache wipe would resolve the problem? A restart, or power off and restart doesn't change anything, and I'd like to avoid a factory reset.

 

[extraclass]

Some apps do not stop when you leave them especially navigation and player apps. Do a search in this forum for "battery" and you will find a bunch of causes and fixes. Before I switched carriers I had to switch off 4G. My phone would drain the battery trying to connect over and over again. A week wifi signal or a weak phone signal will cause battery problems too! Even a bad SD card can cause battery drain! Good luck solving the problem! Let us know what you find.