Is it normal for battery life to get significantly worse after 6 months?

[jcpwn2004]

I've had my gs2 for about 6 months now. Battery life used to be great, 20+ hours on a single charge. The past couple days my battery life has been cut in about half though. I haven't installed/changed anything so I'm not sure what gives....Android OS is only around 30% and everything else looks ok.

Do the batteries just go bad or should I try wiping my phone or something?

 

[nyydynasty]

batteries do go bad but not overnight. if its that drastic over the last couple days, its something thats running. You may not have installed a new app but an existing app may have updated and gone rogue

 

[jcpwn2004]

batteries do go bad but not overnight. if its that drastic over the last couple days, its something thats running. You may not have installed a new app but an existing app may have updated and gone rogue

That makes sense, how can I discover the rogue app if the battery usage isn't showing anything?

I rechecked this morning and dolphin browser was at 20% even though it supposedly wasn't open so I reinstalled. Now android OS is at 46% though, that's pretty high isn't it?

 

[fldude99]

Yeah, something is running. Watch dog is a pretty good app, but doesn't really pinpoint the rogue app. Rebooting for me will clear out whatever is draining the battery

 

[surf1]

That makes sense, how can I discover the rogue app if the battery usage isn't showing anything?

I rechecked this morning and dolphin browser was at 20% even though it supposedly wasn't open so I reinstalled. Now android OS is at 46% though, that's pretty high isn't it?

Download Badass Battery, free, and it works great. Many settings to let you monitor what's using what from CPU usage to screen time, power use etc, you can also see if there's a crazy amount of wakelocks which can drain battery a good amount... really good to help you pinpoint a Rogue app or just to monitor in general and see what's using what.

Battery may need a calibration too, if you were rooted I'd say use Battery Calibrate which rocks when changing/updating Roms to make sure Batt is reporting correct stats. But for stock this is what I did when I got the phone and battery life was quite better vs 1st couple days w/o doing that.
From XDA:
1. Turn off your phone.
2. Fully Charge.
3. When getting 100% signal, unplug quickly.
4. Pull off the battery and put it anywhere.
5. Wait for 180 seconds exactly (be careful )
6. Meanwhile, take this opportunity to dust off the internal compartment.
7. Put back the battery on the right side.
8. Turn on the phone.
9. Pray the Battery god
10. ... and voil