Battery operating time varies depending on operating conditions. You can install an optional
second battery in the module bay to significantly increase operating time. For more information
about the second battery, see your User’s Guide.
Operating time is significantly reduced when you perform operations including, but not limited to,
Using optical drives, such as DVD and CD drives
Using wireless communications devices, PC Cards, or USB devices
Using high-brightness display settings, 3D screen savers, or other power-intensive programs
such as 3D games
Running the computer in maximum performance mode
NOTE: It is recommended that you connect your computer to an electrical outlet when writing to a CD or
You can check the battery charge before you insert the battery into the computer. You can also set
power management options to alert you when the battery charge is low.
CAUTION: Using an incompatible battery may increase the risk of fire or explosion. Replace the
battery only with a compatible battery purchased from Dell. The lithium-ion battery is designed to work
with your Dell computer. Do not use a battery from other computers with your computer.
CAUTION: Do not dispose of batteries with household waste. When your battery no longer holds a
charge, call your local waste disposal or environmental agency for advice on disposing of a lithium-ion
battery. See "Battery Disposal" in the Product Information Guide.
CAUTION: Misuse of the battery may increase the risk of fire or chemical burn. Do not puncture,
incinerate, disassemble, or expose the battery to temperatures above 65°C (149°F). Keep the battery
away from children. Handle damaged or leaking batteries with extreme care. Damaged batteries may
leak and cause personal injury or equipment damage.
Checking the Battery Charge
The Dell QuickSet Battery Meter, the Microsoft Windows Power Meter window and
the battery charge gauge and health gauge, and the low-battery warning provide information on the
For more information about checking the charge on the second battery, see your User’s Guide.
Dell™ QuickSet Battery Meter
If Dell QuickSet is installed, press <Fn><F8> to display the QuickSet Battery Meter.
The Battery Meter window displays status, charge level, and charge completion time for the battery
in your computer.
NOTE: You can use your docking device to charge a computer battery. However, a battery in a docking
device does not power the docking device or computer.
Dell Precision Mobile Workstation M20 Quick Reference Guide