Multipower lights vs. 18650 only lights

A number of the DX lights are available in 18650 only or multipower (both CR123s and 18650). I realize they require different circuits. Are there any generalizable findings about comparing these? Which is likely to be brighter? Give longer runtime? What are the advantages and disadvantages of each? Is there a difference between the multipower running 18650 and primaries? Is there a difference between the singlepower 18650 and the multipower running 18650?

For example:

This: http://www.dealextreme.com/details.dx/sku.8537
versus this: http://www.dealextreme.com/details.dx/sku.8672

Check out the thrower review in my signature - it compares the Q2 versions of those two lights. Result should generalize to the Q5s.

not sure I completely understand your question.

but, if what you are getting at is to see whether moving from 2xCR123A to a 1x18650 gets you anything, you can look at the Lumapower M1 which can use both.

I have the XRE CREE version, and there you can see that the 18650 gets you a lot more runtime, but gives up a few lumens to do it.

For instance, on high, you'd go from 115 to 90 (manufacturer estimated) lumen, but increase runtime from 1.2 hrs to over 4 hrs!

On low, you'd lose lumens from 47 to 25, but runtime would increase from 6 to 26 hrs.

So, the bottom line is if the lumens you get out of the 18650 is good for what you need, you go for it because you should get a lot more runtime and save a lot of money in the long run as well since rechargeables have a much lower cost to operate.

And for those occasions where you absolutely must have those extra lumens, you just use the primaries--just get a light that uses both types.

Thanks, that is what I'm getting at....but Selfbuilt's review also answers one question. With essentially the same light, the 18650-only version puts out more lux than the multipower light with 123 primaries OR 18650. It also puts out less lux on low (which doesn't make a lot of sense to me). For my particular use (lighting up channel markers on the water in the dark) I need maximum throw, regardless of battery cost. The fact is primaries would be easier to use, and I"m not sure these differences would be visible, but thanks for the input.

With multiple power lights(EX:input voltage 3.7-8.4v) the circuit will work over the whole range but be optimized for a certain voltage in that range(circuit designers choice). Generally speaking a 2 RCR123(2 CR123) would be the brightest at the expense of runtime. The best compromise is a light designed to work on an 18650(input voltage ~ 2.7-4.2) it will be more reliable(the greater the # of cells, the more likely you will get a bad or weak cell- bad matched set), just about as bright, and have a much longer runtime.

spec's looks great for a $40 shipped light.

has anyone gotten one yet?

davidra said:

A number of the DX lights are available in 18650 only or multipower (both CR123s and 18650). I realize they require different circuits. Are there any generalizable findings about comparing these? Which is likely to be brighter? Give longer runtime? What are the advantages and disadvantages of each? Is there a difference between the multipower running 18650 and primaries? Is there a difference between the singlepower 18650 and the multipower running 18650?

For example:

This: http://www.dealextreme.com/details.dx/sku.8537
versus this: http://www.dealextreme.com/details.dx/sku.8672

Click to expand...

Comparing the multipower WF-400 and 18650 WF-400, it is my opinion that the 18650-only version has the longest runtime and is also quite clearly the brightest. I suspect that this issue will vary from light to light because of different circuits. (18650-only > 2X16340-multipower > 18650-multipower)

From what ive seen, it seems like circuits that are optimized for only 1 specific type of cell tend to be the best. for example, if i know i want to use one AA nimh, im best off getting a light that runs on only that, instead of one that also supports 14500 li-ion or 2xAA. maybe by including the ability to accept a higher voltage, they have to sacrifice some of the efficiency at lower voltages. im sure this does not apply to every circuit in every light, and probably applies more to AA sized lights specifically because its so hard to get enough juice out of 1 AA.

cy said:

spec's looks great for a $40 shipped light.

has anyone gotten one yet?

Click to expand...

I bought the multipower Q2 version, but was sent the 18650 version (WF-600). I've got 18650s on the way. I have run it briefly on 2 primaries. It is the farthest throwing light I've ever owned. I need a major thrower, and this makes my SL TL-3 look like a Photon. And it was like $22 shipped. This was my first exposure to DX lights. Since they screwed up, they gave me a discount so naturally I ordered a number more which haven't made it here yet. If someone would have said a year and a half ago there would be a light for $20 that throws like a spotlight and uses an LED, we would have thought they were crazy......

I had bought the WF-600 Q2 18650-only version from DX, but they sent me the multi-power. It was apparent to me that the multi-power wasn't as bright as my other 18650-only lights.

In just looking at capacity, the 18650 battery has about a 50% advantage over 2xRCR123A batteries. Then take into account power efficiency to drive ~3.7Vf LEDs, the 18650 can provide even more power. And the physical size of an 18650 is just about the same as 2xRCR123As.

I'd always pick the 18650 optimized configuration over the 2XRCR123A.