Chinese 1 or 2 AA Cell Flashlight Battery Life Test

Updates
5-21-12
Someone asked me to do a run time test on this thing to determine what the typical battery life is. So I brought it to work with me today along with some Ray-O-Vac platinum rechargable AA batteries that were recently recharged. I put the batteries in the light and turned it on and hung it from my cork board behind the door in my office where I can keep on eye on it through out the day. I started the test about 8:10 am.

I didn't pay real close attention to it. I know it seemed fine around 1:30 pm with no discernable change in the perceived brightness level. However, when I looked at it around 4:15 pm, it had shut off altogether. I turned the tail switch off and left it sit for an hour or so and turned it back on. It went back to being about as bright as it appeared previously, but dimmed after a short period of time. I guess the batteries recovered some in the meantime. In any case, I checked it periodically during the morning for overheating, and while the lamp end did warm up, it was no more then just barely noticable.

5-22-12
Tried again today. I turned the flashlight on at 8:30 am. I noticed it got kind of dim around 3:15 pm. I turned it off for about half an hour and then turned it back on. It went back to being pretty bright, but did not stay bright for long. Tomorrow I will try it in one cell mode.

5-23-12
I turned it on with just the one cell about 8:20 am this morning and hung it on my cork board. To my untrained eye, it appears to be about as bright as with both AA cells in place.

At 5 pm when I left for the day, it was still as bright as it was when I turned it on this morning. I checked it periodically throughout the day and it never seemed to get even a little bit warm like it did with both batteries in place. I just left it on when I left for the day.

5-24-12
I fully expected the light to have shut off or at least dimmed by the time I came in this morning. But it seems as bright as when I left work last night. Totally unexpected.

It was still going strong around 2 pm, but when I looked around 2:50 pm, it was noticably dimmer. So, I just shut it off about 3:30 pm. It was quite dim by then.

5-25-12
Thought I would try it in 2 cell mode again. Turned it on about 8 am when I got in. I noticed it was still bright about 2 pm, but around 2:15 pm it appeared noticably dimmer. By about 2:30 pm, it was quite dim, so I shut it off for the day.

After I got home I converted it to single cell mode and turned it on again starting about 5:25 pm. It was still going strong when I went to bed that night, and when I got up the next day. In fact it was still just as bright about 11 pm on 5/26/12 when I went to bed. It was still going when I got up in the morning on 5-27-12 about 7 am, but just barely. Quite dim.

5-27-12
I put another battery in about 7:20 am for another run in single cell mode. It was still pretty bright when I left on an errand on 5-28-12 about noon. When I got back about 1 pm, it was quite dim.

Conclusions:

In 2 cell mode it is not substantially brighter (if at all) than in 1 cell mode.

In 2 cell mode, battery life with the batteries I used is 7-8 hours.

In single cell mode, battery life with the batteries I used is about 30 hours.

I did notice something odd in single cell mode. For some reason while handling it, sometimes the light would flicker on and off. Maybe the switch just doesn't work all that well. It did not do it all the time, but enough that it was noticable and somewhat of a concern that it might develop into a permanent problem.

However, for $3, it is hard to beat. Based on the light output and battery life, it might seem like it is a no brainer to use it only in single cell mode. However, I have noticed that it is somewhat handier in some respects to have the longer flashlight. It is not like I use flashlights all that much anyway.

Thread on another forum about this here.