The worst advice I've gotten about this topic. I followed the advice but couldn't get more than six hours total. I since reinstalled juice defender and am getting about 11 hours with heavy use.
here is what u did wrong you was charging your phone with bad power source
and as you see that happen to me last night
it's bad charging the phone cannot read the battery percentage right !
all what i did to fix this i charged my phone again normal charge on 15% after the bad charge after that the phone reads only +6 of use
how i fix it i used my phone until the battery all dead no power i took my battery out for one min and i put it back again
charged my phone in stable power source offline means i turn it off normal charge will take 2 hours almsot leave it one full hour again or tow
it will back just like this
here with normal use next photo i was sleeping so it's normal to read the battery in standby mode