As you charge the tablet more and more the battery will last longer. My tablet was only managing 3 hours at the start now depending on what i am doing or how long i am leaving the device in standby i can get anywhere from 5 hours (Normal usage on Balance with a few games) to a whole 1 day and 2 hours (very light usage and mainly in standby).
Also just like phones Bluetooth is a complete power whore so your best bet is to turn it off when its not in use.
Retired Mobile: HTC Wildfire (Buzz) Hboot: 1.02.000 (Superversion)
SecureFlag: On (Was Off'd with XTC Clip)
Rom: None Blanked for Testing Roms!!!!!!!!!
Boot Manager: Full Version Paid and Worth It!
New Mobile: HTC Desire HD
SecureFlag: Off Via XTC Clip (I love my clip its so nice!)
Rom: Pacman Rom
Advent Nvidia Note 7 Tegra 4
Recovery: CWM 220.127.116.11