Laptop computers are designed to recharge the battery while the laptop is plugged into the AC adaptor "brick." After a period of time, however, the battery may begin to fail to recharge fully, may seem to have a shorter charge-life or may no longer charge at all. This is quite common: Laptop battery technology just isn’t in place yet to guarantee long battery life and flawless performance. Unfortunately, there may be little you can do to revive a really dead battery except to replace it.
Remove the battery from the laptop. Look at the sides of the battery. You may find a small panel with three or four LED lights or some kind of labelling referring to battery life. Depress the button or part of the panel that appears to light the LED lights. If your battery is functioning normally, you will see one, two or three “light bars” indicating the amount of charge left in the battery. If none of the lights appear when you test the battery, chances are the battery is dead and can no longer take or hold a charge.
Place the battery back into the laptop. Turn it on, using AC adaptor power. When the desktop boots, look for the battery indicator icon in the lower right hand corner of the screen, down near the clock. You should see a battery picture. Hover your mouse over this icon to see how much power is left in the battery. Windows should tell you that the battery is now charging. If there is a red X over the battery, the battery has no charge at all and is probably dead.
Go to “Start,” “Control Panel” and “Power Options.” Check the battery recharging tab. If the battery is able to take a charge, there will be an indicator that charging is happening now. If the battery can no longer take a charge, there will probably be a red X over the battery icon. Shut down your laptop.
Remove the battery and place it in a plastic bag with a zipper lock. Place the battery in the freezer compartment of your refrigerator for 24 hours. At the end of the 24 hours, remove the battery from the freezer and let it “thaw” for two hours. Put the battery back into the laptop (being certain that it is completely dry first). If you’re lucky this freezing may bring the battery back to life—at least for a short time. If the battery is still dead, your diagnosis is over.
Replace the battery if all else fails. Visit the site of your computer's manufacturer for the exact replacement battery for your make and model of laptop. Buy only new batteries.
Consider buying two batteries. This will extend your laptop’s use in situations where you must work on battery power for more than a few hours, such as in a car or on an aeroplane. You’ll be able to swap out a dying battery for a fresh one until you can find an electrical socket.
Don’t expect a laptop battery to provide power for the amount of time “suggested” by the manufacturer. The amount of time that a laptop battery “should” run, before it dies, will vary according to your computer activities. If you are trying to watch a video or play a computer game, much more “juice” will be expended during these activities than if you were just trying to create a document. Never connect a laptop to an automotive power supply adaptor as a substitute for running on the laptop battery. You likely will damage or destroy your laptop.