A WERNER 9V alkaline battery on a 5m string of 12V IP68 LED lights.

Tests to see if the battery + lights would work well for lighting up a buoy at night for a moonlit race and be completely powered by a 9V battery.

Initial Voltage of Battery = 9.7 V

Once connected the lights slowly got dimmer but stayed solid for the remaining time. V measured on calibrated Oscilloscope.

Ending Experiment with Battery when LEDs very dim at 79 h (Voltage = 6.976 V ). Would be ok for nighttime viewing on a buoy.