Question by : Should I take the battery out of my laptop when running on mains power?
My French housemate told me that if I leave the battery in my laptop when it is fully charged and I am running on mains power it will ruin the battery. I don’t believe him, and now we have a bet. Who’s right?

Best answer:

Answer by Tony
When using a laptop as a desktop replacement the battery should not be left in for long periods of time. The laptop will over time discharge the battery. Remove the battery – making sure that it is charged to 40% and store it in a dry, warm place. Ensure that it is wrapped protectively and nothing will be dropped on it.
The battery should be re-installed every 3-4 weeks and allowed to fully discharge. Leaving a battery in storage for longer than this without using could cause the battery to fully discharge as the circuitry of the battery itself consumes power.
http://mobileoffice.about.com/od/usingyourlaptop/f/laptopbattery.htm
Leaving a battery in a laptop while using an electrical outlet for long periods of time will keep the battery in a constant state of charging up and that will reduce the life cycle of the battery.

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