IBAM, the Intelligent Battery Monitor

IBAM is an advanced battery monitor for laptops, which uses statistical and adaptive linear methods to provide accurate estimations of minutes of battery left or of the time needed until full recharge.

IBAM is hosted at Sourceforge. This is the IBAM project page at sourceforge, and new versions will be announced at the project page of IBAM at freshmeat. Read about ibam at sweetcode.

You may download the current version 0.4 here at

ibam-0.4.tar.gz,
ibam-0.4-1.i386.rpm,
read the current README file
or the CHANGES.

The Motivation:

All currently available battery or apm monitors keep telling me that my laptop is able to run for 200 minutes (3h 20min) with fully charged batteries. The reason for this is that the bios computes these inaccurate numbers from the "intelligent" batteries and the apmd just forwards this information to all applications. Even worse is that the last "bios" hour is only about 20 minutes in terms of our understanding of time.
IBAM solves this problem by creating a battery and charge profile (as seen on the right for my computer) from which it can compute the actual times remaining. The red graph represents the battery cycle (where the laptop is running on battery), the x-axis represents the bios-minutes, the y-axis the actual average lengths of that minute in seconds. As you can see the bios minute is about 50 seconds long from 200 minutes to 60 minutes, and only 10 seconds long from 40 minutes to 20 minutes. No wonder I was surprised that the battery was empty so soon... ;)
The green graph shows the charge cycle, which seems to be a bit more useful, still the same technique can be used to give the user an idea how long the charge process will need.
As soon you created initial profiles you can get the same graphs for your computer by using the option "--plot".
Of course the computer will consume more energy on a high load and IBAM does take this into account by determining a short-term linear adaptive method.

Some example output (alias screenshots... ;):

Battery is fully charged and power cable attached:

$ ./ibam
Total battery time:          2:11:33
Total charge time:           1:36:13
$

Laptop is running on batteries:

$ ./ibam
Battery time left:           1:10:25
Adapted battery time left:   1:15:44
$

Charging batteries:

$ ./ibam
Charge time left:            0:30:17
Adapted charge time left:    0:31:30
$

Available options:

$ ./ibam --help
IBAM-0.4, the Intelligent Battery Monitor
(C) 2001-2005 Sebastian Ritterbusch

Usage: ibam [options]

Options:
   -h, --help                 displays this message
   -v, --version              displays software version
   -b, --bios                 show bios apm guesses
   -s, --seconds              displays times in seconds
   -c, --correctseconds       displays changes in seconds
   -r, --readonly             no files will be updated
   -a, --all                  show ALL information
       --battery              show battery time
       --batteryadaptive      show adaptive battery time
       --batterybios          show bios battery time guess
       --percentbattery       show battery percentage
       --percentbios          show bios percentage
       --charge               show charge time
       --chargeadaptive       show adaptive charge time
       --percentcharge        show charge percentage
       --totalbattery         show total battery time
       --totalbatteryadaptive show adaptive total battery
       --totalcharge          show total charge time
       --totalchargeadaptive  show adaptive total charge
       --plot[=profiles]      use gnuplot to plot battery and charge graphs
                              and plot the last <profiles> additional profiles
       --plotderivations[=profiles] same as above plus standard derivations
       --import               import V0.1 data from current directory
       --profile              enable additional yet unused profiling
       --noprofile            disable additional profiling
       --credits              to everyone contributing to ibam

Total battery time:          2:11:33
Total charge time:           1:36:13
$

You are strongly invited to use my code in on of the many (GPLed) graphical frontends.

Sebastian Ritterbusch, 12.11.2005