Re: Does a laptop battery drain even when the laptop is off?
Even when your computer is completely shut off, your battery goes into what is know as stand by mode.
Now, the degree of which you are describing it too extreme. In stand by, your battery would take days even to drain a small amount (4 or 5 percent.) Your battery obviously has something wrong, and likely needs to be replaced.
Some electronic shops can actually build you a new battery if you bring in your old one, it's essentially just replacing the cells.
Hope this helps.
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