you have two possible issues:
1. the cable you are using to charge has deteriorated. get a new one, discharge to 5% and charge it properly all the way up. this is the exact same thing that occurred to me just recently on my N4 (was using the g2 charger for it).
2. you have a bad app constantly running, depleting your battery by the tenfold.
Still waiting for the answer as to whether upgrading from my ROM version 12/30/2012 to one of the more recent nightlys will help solve this problem.