Dell Precision M2300 (Late 2007) - Manual (Page 17)

Quick Reference Guide
17
To check the battery health using the charge gauge, press and hold the status
button on the battery charge gauge for at least 3 seconds. If no lights appear,
the battery is in good condition, and more than 80 percent of its original
charge capacity remains. Each light represents incremental degradation. If
five lights appear, less than 60 percent of the charge capacity remains, and you
should consider replacing the battery. See "Specifications" in your User’s
Guide for more information about the battery operating time.
Low-Battery Warning
NOTICE:
To avoid losing or corrupting data, save your work immediately after a
low-battery warning. Then connect the computer to an electrical outlet. If the
battery runs completely out of power, hibernate mode begins automatically.
By default, a pop-up window warns you when the battery charge is
approximately 90 percent depleted. You can change the settings for the
battery alarms in QuickSet or the Power Options Properties window. See
"Configuring Power Management Settings" in your User’s Guide for
information about accessing QuickSet or the Power Options Properties
window.
Charging the Battery
When you connect the computer to an electrical outlet or install a battery
while the computer is connected to an electrical outlet, the computer checks
the battery charge and temperature. If necessary, the AC adapter then charges
the battery and maintains the battery charge.
NOTE:
With Dell ExpressCharge, when the computer is turned off, the AC adapter
charges a completely discharged battery to 80 percent in about 1 hour and to
100 percent in approximately 2 hours. Charge time is longer with the computer
turned on. You can leave the battery in the computer for as long as you like. The
battery’s internal circuitry prevents the battery from overcharging.
If the battery is hot from being used in your computer or being in a hot
environment, the battery may not charge when you connect the computer to
an electrical outlet.
The battery is too hot to start charging if the light flashes alternately
green and orange. Disconnect the computer from the electrical outlet and
allow the computer and the battery to cool to room temperature. Then
connect the computer to an electrical outlet to continue charging the battery.