10 ways to make laptop battery last longer

Paraphrased from a Right Choice magazine article with my own opinions:

1. Keep the brightness of the screen as low as possible. If portability & long battery life are important for you then buy a laptop with a lower screen size. The laptop's biggest power drain is the screen.
2. Disable Wi-fi and Bluetooth when not needed
3. Unplug all external devices
4. Run only as many programs as you need. If you have a 100 browser tabs open, your battery life will be about 1 hour shorter.
5. Lower or turn off the volume
6. Keep the laptop in a cool place and avoid propping it on a pillow as this blocks airflow to the fan, causing it to heat up.
7. Defragment your hard drive
8. Clean the battery's metal contacts. Clean contacts increase the energy efficiency. Always clean them when the battery is fully-drained, and use a cloth that's only slightly damp, to avoid electric shocks and short circuits. 
9. Shutdown or hibernate your laptop instead of putting it on standby if you're going to be away for long hours
10. Turn off unwanted programs or processes that work in the background.

From Wired magazine: In order to squeeze as much life out of your lithium-polymer battery, once your laptop hits 100 percent, unplug it. In fact, you should unplug it before that. Battery University states that a battery charged to 100 percent will have only 300-500 discharge cycles, while a battery charged to 70 percent will get 1,200-2,000 discharge cycles. So  ideally charge batteries to 80 percent then let them drain to about 40 percent.

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