If you're receiving a low amount of battery life for your laptop, it may be helpful to reset the battery. How to reset it varies based on whether your laptop has a removable or non-removable battery.
Reset a Removable Laptop Battery
Remove the power cord from your computer and turn it off completely.
Turn over the laptop, and push the battery release button or buttons to remove the battery pack from the laptop. Remove the battery and press the Power button for 15 seconds to drain any remaining electrical charge in the computer's system.
Reinsert the battery pack into place, plug in the power adapter and re-boot your laptop.
Reset a Non-Removable Laptop Battery
Perform a Soft Reset
Power down your laptop, unplug the power adapter and disconnect any external peripheral devices. Hold down the Power button or alternate battery reset button combination for at least 10 seconds, until the laptop powers off.
Plug in the power adapter into your laptop without reconnecting the peripheral devices. Press Power button to start your laptop. If this does not work, consider doing a hard reset.
Perform a Hard Reset
Disconnect the power adapter and turn over the laptop. Locate the battery reset hole at the bottom of your laptop. Use a slender object such as a pin or small, straightened paperclip to prod inside the battery reset hole and press the battery reset button.
Remove the pin, reconnect your power adapter and turn on your laptop to resume normal use.