The CPC can be powered in two different ways. Each has its own benefits and drawbacks.
The first power source is an AC adapter. For the CPC, Celestron recommends one giving a 12 volt DC output at 2.5 amps, tip positive. Simply plug in the transformer to the wall and the DC plug into the base of the mount. Benefits: continuous, reliable power. Drawbacks: you must be near a source of AC power, you must deal with cordwrap and the hazard of tripping over power cords.
The second power source is a 12-volt DC battery. They are widely available because they are standard for use in cars, boats, etc. Benefits include portability and power to run your scope and accessories as long as all night or several nights. Drawbacks include weight and again the inconvenience of the cord running from the battery to the scope. Celestron’s PowerTank is a specialized DC battery power source that has 12-volt and other voltage outputs, plus conveniences like lights and even a radio.