I've got a Marshall V-LCD51 5" monitor that has a 5v marking on it. The instruction manual says it takes anywhere from 5v to 12v. I want to get a Swit D-Tap 14.4 volt battery, which is stated to work with my camera. If I plug my 5 volt monitor into the 14.4 volt D-Tap connector, could that damage the monitor?

I don't have direct experience with that setup, but generally speaking you don't want to exceed the rated voltage. Over rated amperage is ok since it just draws what it needs.

Thanks Stephen. Based on your advice, plus what others have told me, I'm going to skip the D-Tap idea, and just use the small battery made for the monitor.

A straight cable would potentially damage the monitor. You would want to get a special cable with an inline transformer to convert the voltage from 14.4 volts down to the rated range.