I Have New battery which only gets 45 minutes on a charge

Not sure how to deal with this - I bought a new battery but the charge says i get 1:45 minutes though it severely decreases within an hour- i thought it was a bad battery so i traded it in for another fresh one and i get the same results - this happened in 11.10 and now in 12.04 as well. I've tried all suggested fixes- battery draining recharging etc but it seem to be getting worse (unplugged at full charge now says 48 minutes) Everything else is working excellently but a laptop should run off a battery don't cha think?

I've played with everything from Bios settings (and updates) to powertop etc but I'm stumped- this is my travel computer but finding some outlets in some airports is a royal pain! thanks in advance

Description: Ubuntu precise (development branch)
Release: 12.04

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: acpi 1.6-1
ProcVersionSignature: Ubuntu 3.2.0-21.34-generic 3.2.13
Uname: Linux 3.2.0-21-generic i686
ApportVersion: 2.0-0ubuntu2
Architecture: i386
Date: Mon Apr 2 08:48:17 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
SourcePackage: acpi
UpgradeStatus: Upgraded to precise on 2012-03-02 (31 days ago)