Flashlight-oholic and wondering about run times

I dipped back into flashlights briefly a year or two ago by adding the tail cap switch and TerraLUX TLE-20 upgrade to a Mini Maglite and was pleased with the results.

I must start by admitting I am becoming obsessed with flashlights again after buying an Ultrafire WF-501B R2.

I think I am becoming a Flashlight-oholic!

Following this I bought another WF-501B with the Philips Luxeon K2 Red emitter.

Whenever I get a new torch or rechargeable battery I do a burn-in run time test to make sure the LED holds out and get an idea of run time for that battery.

Both these came with 18650 batteries and performed very well, but after reading about them also taking 2 x 16340s with the higher voltage I thought it would be even better. After some reading on this forum I see why this may not be the case but I went ahead and tried anyway.

The results were odd though as when using the 18650 the Cree R2 gives 45 minutes and then just cuts out and the Red K2 gave about 11 hours, but when using the 16340 results seemed reversed.

When using the 16340 there is no noticeable increase in light output with the Cree R2 (so I haven't done the run time test), however the Red K2, (which having such a long run time I assume is drawing a much lower current), would last about 15 seconds before fading to virtually nothing. After allowing the batteries to rest it would be bright again for 15 seconds. With a higher power requirement I would have expected this of the Cree R2 not the Red K2. Any ideas why this is the case?

When buying the 16340s, with one package I got a small single 16340/CR123 torch named 'Smiling Shark 5W super Bright Waterproof SS-6001' which has surprised me. Its performance seems impressive for such a small torch. In fact it lead me to do some more reading in these forums and I decided to order an ITP EOS A1.

See:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=150438448974&ssPageName=STRK:MEWAX:IT

It only has one brightness level which is very high but it has pretty short run time. I have tried it with 1000mAh and 1200mAh batteries and the results fit the capacities. With the 1200mAh it gives full brightness for 15minutes after which it starts to tail off, still bright at 20minutes gradually tailing off to an unusable level at 37minutes.

At all times when giving the full output it gets very hot. At first I left it on the table and after 5 minutes found it very uncomfortable to pick up, so turned it off. If you hold it while it is on you act as a heat sink and it gets hot but not out of control.

Is this sort of high output, low run time normal? Obviously if you have a very small very bright light, logically it will not run for very long, but 15minutes!?

Is it also normal for a small bright torch to get uncomfortably hot?

My first time on CPF so not sure if I have included too many different things in one thread, but it just kept pouring out...

Still waiting for the ITP A1.

2 x 16340 would not be better than 1 x 18650 for several reasons. First-off, the two cells will give a higher voltage of around 7.4V. Using two cells increases voltage, but not capacity because they are in series. However, higher voltage means less efficient regulation, which also leads to extra heat production. There's also the safety side of it, one cell is always safer than using two, and in this situation, there's no reason to use two to begin with.

As for heat, smaller lights have less heatsink material (flashlight body). It is normal, and also why it isn't recommended to use turbo or high mode for extended periods of time.

If you're using those cheap rechargable li-ions (probably unprotected), do yourself a favour and put them in the recycle bin, seriously.

AW brand li-ions are some of the best you can get as they have protective circuitry that won' let you over discharge the battery (VERY IMORTANT).

If that light you bought only has one output level and it gets too hot to handle, place it in the recycle bin too. As stated, some multi-mode lights do get hot when on their highest level, but a single mode, mmm I wouldn't keep it.

Have a look at the gear from 4sevens for affordable quality lights. As well as other gear like batteries and things.

http://www.4sevens.com/