Why does laptop battery show < 100% charge

[M A Young]

On Wed, 16 Sep 2009, Paolo Galtieri wrote:

> This is something that has been driving me crazy over the last several
> weeks.  I have my laptop plugged into AC power and has been plugged into AC
> power for several days now, but the battery applet shows 97.3% charge.  It
> has been showing < 100% for several days and never reaches 100%.  The
> battery is less than 3 months old.  I'm running F11 with all the latest
> updates.
> 
> I would appreciate any ideas as to why this is the case.  There have been no
> power outages so it seems to me there is no reason my battery should show <
> 100% charge.
> 
> In case it makes a difference I'm running wireless on a 3945ABG.  The
> processor is a Intel(R) Core(TM)2 CPU T7200  @ 2.00GHz

This may be down to the bios software. I run my laptop (a Dell Inspiron 
1525) off AC power in both linux (F11 and rawhide) and windows vista and 
the battery charge gradually declines over the months, but the battery 
doesn't charge unless I unplug the AC briefly while the computer in on, 
which prompts the machine to charge the battery fully.

 	Michael Young