Basic Circuit for showing the voltage of a battery

[Voltz]

First of all, thank you all for your past help, you've really eased me into electronics, Think I've realised now though is that there are always several ways to do anyone thing in electronics, I want to make an LED based circuit out of a Bipolar LED (Red/Green) but it should do RED/YELLOW/GREEN if green and red are activated at the same time, so here's what I want to do, because the Circuit is powered by a 9V battery I want it to show green for >8.8V, yellow for >=8 and red for 8< , I was thinking either a zener diode with the correct breakdown voltage? or maybe an opamp and if one of those which one? Anyone got any ideas?

 

[MikeMl]

Maybe you can get some ideas from this. Note the date. I have one of these in an aircraft, so the trip points are optimized for a 12V lead-acid battery system. Also, I wasn't concerned about killing the battery with the current drawn by this circuit, because I have a 60A alternator and a 35AH battery. This circuit alerts me if the alternator trips off line; or if I forget to turn on the alternator field excitation.