The primary advantage of having battery power on a coffee maker is that it is possible to make coffee anywhere (so long as the user has a battery). Such companies as Roadpro make a 12-cup drip coffee maker that draws power from a car battery.
The danger of operating a coffee maker in this way is that, if left connected to the car battery, it can drain the power. The unit is packaged with a power inverter at 800 watts. After the user plugs the coffee maker into the inverter, he can hook up the inverter to a car battery, following the same process that people use when connecting jumper cables.
Running a coffee maker requires a significant amount of electricity, which is why it runs through an inverter rather than through the same socket that people use to charge their cell phones or operate their DVD players while the car is running. For people who enjoy the great outdoors but want to have higher-quality coffee than what they can make on top of a camp stove or over an open fire, a battery-operated coffee maker can be a lifesaver, but taking a set of jumper cables is a wise precaution just in case the coffee maker runs too long.