How to discharge battery - eMachines eM3502074 Tablet PC

You could also take the battery out ,get a 12 volt bulb connected to two wires.connect to the battery and leave it to drain.then put the battery back in and charge you could do the whole thing in less than an hour.
this isn't to say the first solution is wrong in fact its the correct way to do it .my way is just quicker

"Calibrating" a laptop battery is one way to increase the lifespan of a battery that doesn't last long. The procedure involves two steps: fully discharging the battery, then then fully charging it immediately thereafter. It's important to note that a full discharge doesn't mean you drain your battery until your computer powers off, but rather that you deplete it until it reaches a level of approximately 3 percent capacity, according to BatteryCare.com.

1. Charge the laptop battery to 100 percent. Allow the laptop to sit plugged-in and fully-charged for approximately two hours.

2. Click the "Battery" icon in the lower, right corner of the Windows Taskbar and click "More Power Options." Click "Change When the Computer Sleeps," then click "Change Advanced Power Settings."

3. Scroll down to "Battery" and click the "Plus Sign" icon next to it. Click "Critical Battery Level," then click the arrow to decrease the number to "3." Click "Apply," then click "OK."

4. Unplug your laptop and continue using the computer until it reaches 3 percent, at which point it hibernates automatically. Allow the computer to hibernate for at least five hours, then plug it in and allow it to recharge fully.

I hope you find it very helpful. Thank you for using fixya.