Yes, it is battery powered - a coin type battery to be exact. And it is black segmented text like on most calculators. I plan on soldering wires to the PCB traces in order to interface with the display, as I can't solder to the clear ribbon connector.
My guess is that one of the lines is a common ground, and the others all activate a segment. Is there a common voltage that is used to trigger liquid cryslals?
It looks like this
