Originally Posted by SUroot
Yeah it works but if you keep doing it, you'll screw your battery.
A better way would be to let it drain to as low as it can. What happens is your battery has a chip that remembers the max and minimum capacity of the battery but over time, if you constantly recharge your battery at 20%, it will start to view 20% as the lower limit (and show it as 0%) so to let it discharge down until it turns off is good as it lets teh chip "see" the entire capacity. Making it aware of it again.
Thanks for that SUroot. You are right, it's not good to do it often - actually I 've never done it before. I just did it once to "reset its memory" and now it's working perfectly - my battery draining problem is completely resolved after the Jelly Bean 4.1.2 update.