yeah the batterys are SHIT for samsung with my d500 i have to recharge it EVERY DAY sometimes twice a day especially if i made or watched videos or played music that would waste the battery so much and there wasnt much of an indicator for the battery it just had 3bars, so it was kinda hard to tell...

The sony d900 has...
Stand-by Up to 250 h
Talk time Up to 3 h 30 min

however the k800i has...
Stand-by Up to 350 h
Talk time Up to 7 h