Here is a runtime post from a
UK Caving site..
OUR OWN TESTS USING DIFFERENT TYPES OF BATTERY:
NiMh Rechargeable AA Batteries: (Energizer 2500mAh) Usable Light: 11h:00m
Ran for 10h:25m on the middle 40 lumen setting before there was any noticable drop in output, which is considerably longer than expected.
00h:00m: On.
10h:25m: LED's flashed to signify end of regulated output.
10h:55m: Output had reduced significantly but still bright enough to cave on.
11h:10m: Very dim so ended the test.
Alkaline AA Batteries: (Duracell Procell) Usable Light: 8h:00m
Ran for 8h:00m on the middle 40 lumen setting before there was any noticable drop in output.
00h:00m: On.
08h:00m: LED's flashed to signify end of regulated output.
08h:05m: Output had reduced significantly.
08h:20m: Very dim so ended the test.
Lithium AA Batteries: (Energizer Ultimate) Usable Light: 13h:00m
Ran for 13h:00m on the middle 40 lumen setting before there was any noticable drop in output. Not as long as we were expecting bearing in mind that the NiMh rechargables did 10h:25m. Normally there's a strong argument for lithium batteries but possibly not in the Pixa 3 unless using it in very cold conditions. This is probably something to do with the way the Pixa regulates the output.
00h:00m: On.
13h:00m: LED's flashed to signify end of regulated output.
13h:10m: Output had reduced significantly.
13h:15m: Very dim so ended the test.