capsule review

Battery-Status Monitor II

In our recent Software Bargains article, I recommended Battorox (   ) as a useful utility for monitoring your PowerBook or iBook’s battery. In addition to showing how much of a charge your battery has left, Battorox tells you the battery’s cycle count (how many charge cycles the battery has been through), voltage, and temperature.

Since that article, I’ve received a number of reader recommendations for another battery utility sitting in my Mac Gems “To Do” folder, the free coconutBattery 1.3 (   ). This useful piece of software doesn’t show you quite as much information as Battorox, but it displays a couple unique bits of info of its own—and does so via a more attractive interface.

The main coconutBattery window shows you—both in absolute numbers and via an easy-to-read “level meter"—the current charge of your battery; in other words, how much juice you’ve got left. (Unfortunately, it doesn’t give you an estimate of how long that juice will last, but Apple’s menu-bar battery monitor will do that.)


The middle of the window provides information unavailable in Battorox: your battery’s original and current capacity; in other words, how much juice your battery should be able to hold compared to how much it’s actually able to store at this point in its life. For example, in the screenshot above, you can see that my PowerBook G4’s battery originally had a capacity of 4400mAh, but that capacity is now down to 4179. If you’ve got an older PowerBook or iBook that seems to have a very short battery life, run coconutBattery to see your battery’s current capacity—if it’s low, it may be time for a new battery.

(This information is also available via the

command in Terminal, as Rob Griffiths explained in his July Mac OS X Hints column. However, I think you’ll agree that coconutBattery displays the information in a much more user-friendly manner.)

Finally, the bottom of the coconutBattery window displays the cycle count, estimated age of your PowerBook or iBook (which isn’t always correct), and current charger and charging status. One nice feature: If you connect your PowerBook to an AC adapter that provides too little power—for example, some iBook AC adapters don’t provide enough power to both power and charge a PowerBook simultaneously—coconutBattery will warn you.

An interesting feature is coconut Battery’s Saved Data drawer, accessible via the disclosure triangle to right of the Additional Info section. At any time, you can save your battery’s current battery capacity; you can save as many “battery states” as you like, and each will be listed by date. So, for example, you could compare your battery’s capacity today with an updated capacity after a two-week business trip and see if using your PowerBook primarily off the battery for a couple weeks reduced its battery capacity.

coconutBattery Saved Data screen

If you’re curious about the state of your PowerBook or iBook battery, coconutBattery is a handy tool.

coconutBattery requires Mac OS X 10.4 (Tiger).

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