After 30 hours I stopped my test. The batteries were down to 2.98, 3.02, 3.04. It was still on 1 bar and voltage of 8.85V. Just did not want to fall below the 2.8V that is the least U should allow these batteries to go. Now I Know once it reaches one bar it is time to switch out the battery. It can be noted I ran the detector on manual sens of 22. This is about the average I see in the field on Auto +3