3W on ebay question

OK, I saw this 3W flashlight on ebay, and was wondering about the specs.

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Finally 3 watts, up to 75 Lumens of light, in a very compact form(About 3.6 inches long!)

Specifications:

Output Power: 75 Lumens

Bulb Type: 3 watt Luxeon LED, Lifetime of LED (100,000 Hours)

Burn Time: 3+ hours per battery


Body: High Strength aircraft Aluminum, anodized finish, and metal clip.

Battery Type: 1x 3V "CR123A" Lithium Batteries (included)

Dimensions: 92mm x 25mm

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My question is, how long can a CR123 battery hold MAX (750-1000mA) power? The specs imply 3+hrs at 75 Lumen, that dosent sound right. I am thinking of posting my 3W Cyan, Faren topped, DD 14500 Dorcy with a Li-ION charger. But its run time is only 45 Mins or so at 1000mA. I am just wondering how I promote it.

Jeff

I believe the one you saw on Ebay is a Nuwai Q-III. The burn time it refers to is the total time ( 90 minutes full brightness plus another 90 minutes moon mode ). I believed the lumen rating is inflated because Q-III delivers less than half of that 75. FYI, a good CR123 holds about 1300 to 1400 mAH.

90 minutes at full power for a lux-3 is a pipe dream for a 123.. look at lights like the VIP to see an estimate of 'high power'.. typically you can get like 40 minutes max power Lux3 from a single 123. Bump the power down to a more reasonable level (like the 'less than half') and you'll double the runtime and 90 minutes is right in line.

A 14500 LiON should be either 700 or 850 mAH.. = just about 3WH.. a lux3 driven at 1000mA will likely be outputting about 3.75W... that divides to 48 minutes.. so.. makes sense... the average will be a lot less if it's DD, but that loss will be in inefficiencies of over-driving the battery, etc.. 'order of magnitude' it works.

You should figure out the average power and the max power during the useful runtime of the light and say both values... like my ludicrously overpowered 'laborday light'.. which outputs just shy of 5W into a Lux3... 1300mA peak... but averages about 3W over the useful life of maybe 50 minutes... those are honest values. (oh i just finally got my light meter today.. 21,000 lux at 1'.. talk about a light monster).

-awr