The servo lead on that ESC is NOT for the battery slot on your receiver. It is for the THROTTLE slot on your receiver. The power and ground pins on all of the receiver slots are tied together, so the ESC can power the receiver when it's plugged into the throttle slot (or any other slot for that matter). If you plug your ESC into the battery slot, you will have no control of the ESC.

Battery slots on receivers are there to allow you to use all the channels on the receiver AND be able to plug in a separate receiver battery. Some receivers don't have a battery slot, and you must use a y-connector on one of the channels if you wish to use all the channels AND plug in an receiver battery. The Hitec Electron-6 is one example of this, note the CH6/BATT designation on one of the slots (see link below):

http://www3.towerhobbies.com/cgi-bin...&I=LXCXM8&P=ML