Originally Posted by edp

download an app called spart parts and check the battery info to see what's running in the background cus even on stock 2.1 i was getting at least 15 hours after heavy use on one charge. when you look at other usage, the running and screen on numbers should be really close to each other. if your running number is much higher than your screen on number, then you have a runaway app or process thats not sleeping and killing your battery. a common culprit is a process called akmd2 which has something to do with the sensor but no one seems to really know. here's a fix some have tried but use at your own risk:
[FIX] getting rid of the AKMD2 runaway process



also, doing a factory reset can help. after i flashed to 2.1 from 1.5, i was having major issues until i did a factory reset (it's under settings > privacy >factory reset). this is the first thing i would try.


there are also many custom roms ( my personal favorite is radioactive froyo 1.6.2) that give you great battery life. i get 24+hours on average with every charge.
Link on how to install :
Radioactive FroYo v1.8.11 **9.2 MFLOP** **Moment-Acclaim Hybrid** GPS Workaround

dl link for version 1.6.2:
http://www.sdx-downloads.com/devs/noobnl/noobnl-Radioactive-FroYo-romv1.6.2.zip


and the final thing i would try is to reflash the phone back to stock. instructions here:
Sprint Software Downloads - Smartphones - Samsung Moment with Google

hope you figure something out. g'luck