Battery life really depends upon user usage, and other things (the kernel, that I'm talking about).
The kernel's not much to worry about, for there are no wakelocks, and stuff... But, if the ROM is "buggy" (i.e. creates unnecessary wakelocks), one can't do anything but go into the source to fix it.
But, about the USER USAGE, the reason for battery draining... Here's something that featured on the XDA Portal a few days ago:
Battery Saving Mega Guide Celebrating User’s 2000th Post.
Head over to the original thread, here:
http://xdaforums.com/showthread.php?t=2601318, and try following the steps there. LMK, if it helps