Charging the Battery
NOTE: 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.
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.
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 battery light 
flashes alternately blue and amber. 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.
For more information about resolving problems with a battery, see "Power Problems" on page 121.
Replacing the Battery
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 battery is designed to work with your Dell computer. Do not use batteries from other computers with your computer.
CAUTION: Before performing these procedures, turn off the computer, disconnect the AC adapter from the electrical outlet and the computer, disconnect the modem from the wall connector and the computer, and remove any other external cables from the computer.
NOTICE: You must remove all external cables from the computer to avoid possible connector damage.
NOTICE: If you choose to replace the battery with the computer in Sleep state, you have up to 1 minute to complete the battery replacement before the computer shuts down and loses any unsaved data.
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Using a Battery
