JetBeam battery issue/question!

Hi all!

I have spent a decent amount of time looking up previous reviews and posts about my flashlight, but can't locate exactly what I'm looking for, so I'm hoping someone can help steer me in the right direction.

I recently purchased a Jetbeam 3m-Pro which came with two Energizer Cr123a's. The light is extremely bright compared to any light I've ever used, but I knew it would use batteries like crazy. I knew that the spec sheet said that 1100 lumens were only obtained by using two RCR123a's, so I purchased 4 of them (3.0 volt 900maH) , but the light only shines brightly for just a second before dimming. So my questions are...

1. Would using two 3.7v 650maH RCR123a's allow the light to shine like the CR123a's do? Or does the output capability have more to do with capacity than voltage?

2. Does anyone know what the maximum output is for using two CR123a's? It isn't listed on the spec sheet.

3. Would you use an 18650 instead, and put up with the drop of around 200 lumens max output?

Are you sure those were RCR's you got? 3.0v aren't typical for an RCR (16340). If you're sticking with them, then definitely get those that are 3.7 volts. Hopefully there isn't a driver issue causing the dimming effect...because the light is still getting 6v regardless. Many CPF'ers will advise that you ditch the smaller batteries and simply use a 18650. There are often safety concerns in play when using batteries in series. Truthfully too, is that I doubt much of a difference in output will be noticed to your naked eye, whether you're getting 1100 lumens or 900 to 1000 lumens. It might be slight...but not enough to make much of a difference out in the wilds! Now if you're like me...and want full output from smaller cells, then go with 2 - 18350's...which I'm sure the tube is wide enough to accommodate.

As always though, the problem with 2 cells is that they need to be properly matched (voltage-wise) and in excellent health.

Someone else may approach your problem from a different angle, but that's MY take. Keep it simple; use a 18650.

jglaze said:

Hi all!

I have spent a decent amount of time looking up previous reviews and posts about my flashlight, but can't locate exactly what I'm looking for, so I'm hoping someone can help steer me in the right direction.

I recently purchased a Jetbeam 3m-Pro which came with two Energizer Cr123a's. The light is extremely bright compared to any light I've ever used, but I knew it would use batteries like crazy. I knew that the spec sheet said that 1100 lumens were only obtained by using two RCR123a's, so I purchased 4 of them (3.0 volt 900maH) , but the light only shines brightly for just a second before dimming. So my questions are...

1. Would using two 3.7v 650maH RCR123a's allow the light to shine like the CR123a's do? Or does the output capability have more to do with capacity than voltage?

2. Does anyone know what the maximum output is for using two CR123a's? It isn't listed on the spec sheet.

3. Would you use an 18650 instead, and put up with the drop of around 200 lumens max output?

Click to expand...

I would think you won't get much run time with either pair. The ones you just bought are probably too close to the same voltage as primaries to give any more output and the 3.7 volt type aren't going to have the capacity. I doubt you'll get much more than a minute or two at maximum, if that. Yes I would just use an 18650 in it, much better run time.

Edit: Your 3 volt rechargeables may also just need to be charged.

Thank you both for the replies! The cells definitely say RCR123a on them. The package I bought online came with 4 batteries and a charger, I tried all of them after they had fully charged and tested the voltage too.

I'm definitely going to just get the 18650 to use though, thanks again!

I would guess the batteries you have are Tenergy's or something like them. I use them in my surefires I just tried them in my RRT26 with the same result you are having, I think the current draw is to much for them. I use two 18350's in my RRT26 because the output between them and one 18650 is very noticeable. It might not be so noticeable on the 3m-Pro you will have to try it.

Taz80 said:

I use two 18350's in my RRT26 because the output between them and one 18650 is very noticeable.

Click to expand...

Whenever I find a light that accepts 18350's I'm always impressed by the output. They usually perform well...but need a watchful eye for when the voltage begins to drop!