I recently ran into problems with one of the batteries in my 400MHz TiBook. The machine dropped into sleep mode without warning with about 40% remaining charge showing in the menu bar while running on its original 3600 mAh battery, so I downloaded Capacity Meter. This nifty utility reports not only the state of charge, but the working capacity of the battery.

I recently ran into problems with one of the batteries in my 400MHz TiBook. The machine dropped into sleep mode without warning with about 40% remaining charge showing in the menu bar while running on its original 3600 mAh battery, so I downloaded Capacity Meter. This nifty utility reports not only the state of charge, but the working capacity of the battery, and with this problem battery, it reported 2728 mAh of capacity, significantly less than the original spec. The only glitch I encountered was in the percentage of capacity calculation that the software performs, which used 4400 mAh as a baseline. The author explained that the software is currently unable to detect the specific battery revision and instead uses a capacity value that he specifies for each machine type, even though the available batteries may differ in their rated capacity.
I was curious to find out the condition of my other battery as well as the one in my wife?s identical TiBook. Thankfully, the other battery reported a capacity of 3432 mAh, very good for a battery that is more than three years old. When I checked my wife?s battery it reported 1496 mAh, quite poor, but undetected, as she almost never works without the power cord plugged in.
This prompted me to retire her 1496 mAh battery and donate my 2728 mAh battery to replace it. I am looking forward to getting a NuPower 4800 mAh battery to use as my main battery. I am hoping that the combination of lowly 400Mhz processor and significantly higher spec battery will transform the already impressive runtime of this TiBook into the Lon Haldeman of laptops.