Battery life

This is a reocurring topic, so I thought I'd pass along the following
piece from the Washington Post G4 battery life:

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April 7, 2005

Maximizing the Life of the G4's Battery

By J.D. BIERSDORFER

Q. I use my PowerBook G4 at home and on the road, and I would like to
maximize the life of its rechargeable battery. Is it best to leave it
plugged into a power source at home, or to leave it unplugged so it can
discharge and then recharge it as necessary?

A. Apple Computer does not recommend leaving the PowerBook plugged in
all the time with its lithium-ion battery connected because the internal
chemistry can stagnate, which may shorten battery life. Unplugging the
laptop and working from the battery once a month or so helps to
discharge the stored energy and gets those electrons moving.

The company also recommends that you calibrate your laptop's battery
every few months. Laptop batteries contain microprocessors that tell the
computer how much of a charge is left, but they can get out of sync.
This causes the computer to give incorrect information about the charge
status. Calibration helps the battery and computer communicate more
accurately.

To calibrate the battery, start by making sure it is fully charged and
showing the green indicator light on the power adapter. Then unplug the
power adapter and use the laptop on battery power until the machine goes
into Sleep mode. Once it goes to sleep, the battery has been drained and
you can connect the power cord and charge it back up.

If you occasionally run the PowerBook from the battery but typically
keep it plugged into a power outlet while you work, Apple recommends
fully discharging and charging the battery at least once a month. There
are other tips on PowerBook battery care at
www.apple.com/batteries/notebooks.html.

On the subject of Mac laptop batteries, Apple is recalling certain
batteries made by LG Chem that were sold from January 2004 to August
2004 for PowerBook G4's with a 15-inch screen. The affected batteries
may have an overheating problem. You can get details on how to find out
if you have one and how to exchange it at
https://depot.info.apple.com/batteryexchange/index.html.


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Copyright 2005 The New York Times Company