1 other suggestion (which i doubt is the case) would be to recalibrate the battery..
the simple wiping battery stats in recovery thing doen't work how it used to but i know of 1 method which proved very very useful when i had the lg esteem,
step 1 is to charge phone too 100%
step 2 is to (once phone is at 100%) reboot the device with wire still plugged in
step 3 as the boot animation begins to appear, pull the battery out...
step 4 wait 20 seconds then place battery back in and leave the device alone, wait for the charging screen to appear and see where the percentage is.. if you are anywhere under 90% than repeat the proccess a few times untill the device remains around 98% after powering on etc...