Kite LEDs
What do you want the LEDs to do ... ?
If you just require night lighting then a 3 volt battery would be OK as there will be minimum volts drop across series resistors
As you mention CMOS are you creating some flashing display ? a higher voltage may be required for the logic.
I doubt that a couple of AAA cells will give much life, maybe a few minutes. You should consider something bigger - 20 square feet of sail should carry 3 or 4 'D' cells without too much difficulty :wink: