i dont knwo a lot about electronics so can someone put up a quick sketch of what i need and how to set it to show 9 volts at full bars and 7 volts at zero bars. I would need to make this be kinda small and it would be spliced off of the positve/negative wires going to my board from the 9 volt. Also im trying to make it so it doesnt consume much power
Leds consume power with their brightness and with the amount of time they are lit. You could reduce their power by making them dimmer, flash them momentarily or "on-demand" turned-on with a push-button. :lol:
Are you wanting to power it from the battery you are measuring (self-powered)? If so, to save power you should run the display in dot mode instead of bar mode (which you suggested).