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Ultracapacitor LED Flashlight Charges In 90 Seconds

Iddo Genuth writes "The California based company 5.11 Tactical has recently introduced a new innovative flashlight — 'Light For Life' UC3.400. Unlike regular flashlights requiring constant battery changing this new LED torch offers a rechargeable battery that can be recharged in as little as 90 seconds using ultracapacitor technology. Various military and rescue units might benefit from this new development, ensuring them a light source at all times."

14 of 131 comments (clear)

  1. 90 seconds! by hansamurai · · Score: 5, Funny

    ensuring them a light source at all times.

    Except those 90 seconds.

    In which you will be eaten by a grue.

    1. Re:90 seconds! by click2005 · · Score: 4, Funny

      Yeah and it'll be like every PC FPS with a flash light (HL2/F.E.A.R etc) where it lasts 30 seconds at a time.

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    2. Re:90 seconds! by Elder+Entropist · · Score: 3, Informative

      Except those 90 seconds.

      In which you will be eaten by a grue.

      You should still be fine if you don't move more than once during those 90 seconds. You have to move twice in the dark to get eaten by a grue.

    3. Re:90 seconds! by SleptThroughClass · · Score: 4, Insightful

      That's actually a myth, the flashlight in Doom 3 is actually grue powered.

      Do they have a small grue on a treadmill, forever running away from the light which it generates?

  2. Better be a mighty fine flashlight for $170 by jfengel · · Score: 5, Insightful

    TFA says it's a $170 flashlight. It's got a lifetime warranty, but I always lose flashlights before they fail on me.

    What I want to know is, how quickly does it self-discharge? It doesn't do me any good to have it charge in 90 seconds if I don't need it until the power goes out.

    1. Re:Better be a mighty fine flashlight for $170 by Feanturi · · Score: 4, Insightful

      I paid $10 for a wind-up flashlight that appears to have the same style of 3-LED array as this one. It's nice and bright, requires about 1 minute of winding to provide 15 minutes of full illumination, with less-bright light available after that. Considering that I never need anything other than a working pair of hands to charge it, I think the one I've got is much better for ensuring there will always be light when I need it. In a power outage, or out in a tent somewhere, a 90-second DC charge time doesn't do me any good at all.

    2. Re:Better be a mighty fine flashlight for $170 by onkelonkel · · Score: 3, Funny

      One of my favorite old detective stories described a cop's 6 cell mag lite like this "except for the fact that it lit up when you pressed a button, it would not have been out of place at the battle of Agincourt"

      --
      None of them can see the clouds; The polished wings don't care.
  3. Limited usefull information. by B5_geek · · Score: 4, Informative

    VapourWare: Lights will be delivered on a first come, first serve basis in early 2009.
    90-minute runtime
    270 Lumens

    The claim is 270L for 1.5h, using three emitters. It looks from that close-up of the head that Crees are used, so most likely XR-Es. I'll use a rough 100L/W for my estimates.

    270L/3 = 90L per emitter

    90L corresponds to about 350mA at 3.2V (very roughly) from an XR-E.

    If*Vf*emitters*time = energy

    0.35A*3.2V*3*1.5h = 5.04Wh

    So, the supercap has about 5Wh in it (again, very roughly).

    The above assumes 270L at the emitter. Let's say it's 270L OTF, which would mean around 360L at the emitters.

    360/3 = 120L per emitter

    120L corresponds to, say, 450mA at 3.3V or so.

    0.45A*3.3V*3*1.5h = 6.7Wh

    This more optimistic estimate (in terms of both energy storage and lumen claims) puts us at a little under 7Wh for the supercap used in the light.

    Let's see what we get with a common AW 18650:

    3.7V*2.2Ah=8.14Wh

    So, this flashlight's power source has around 62% (pessimistically) or 82% (optimistically) of the energy of an 18650, but is several times the size.

    I think I'll pass on this one.

    --
    "The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
    1. Re:Limited usefull information. by captaindomon · · Score: 3, Insightful

      The AW 18650 is a lithium ion rechargeable battery. This is a capacitor system, they are a very different technology. Try to get an AW 18650 to recharge in 90 seconds. It will asplode.

      --
      Just because I can hook a shark from a boat, I do no offer to wrestle it in the water.
    2. Re:Limited usefull information. by jdong · · Score: 3, Informative

      Oh without a doubt in my mind, from my experience with being a flashlightaholic (my collection of lights totals about $2000-ish), 5.11 is playing a few common low-grade marketing games here:
      (1) Advertising emitter lumens instead of out-the-front lumens. The number almost certainly doesn't account for losses in the reflector.
      (2) Advertising emitter lumens at peak driveable Vf and current. Almost every vendor except the Inova T-series and INFORCE (military) series does this -- they put a lumens number on the box that is taken from the spec sheet. Then, they do not actually drive the emitter at the power required to produce this amount, usually because it generates too much eat or returns too low of a runtime.
      (3) Advertising useless runtime. My NiteCore D10 is a 1xAA Cree Q5 based emitter. On a 2000mAh NIMH cell, it produces a little over 2 hours of full DC-DC regulated brightness. Then, the output tapers off and goes into a "moon" brightness for 24 hours so you can find your next set of batteries. So, does this have 120 minutes of runtime or 24 hours of runtime? I'd say realistically the former -- Nitecore advertises the former (runtime to 50% brightness) -- but I've seen far too many products in this industry advertise the latter.

      Bottom line is Inova's new INFORCE series military lights produce 150 or so out-the-front lumens and the light costs close to $200 MSRP. I don't see this product performing even in that ballpark. Press release = marketing speak; call me back when a reputable source produces a runtime graph and output graph.

    3. Re:Limited usefull information. by sslo · · Score: 3, Informative
      Actually, your calculations are even further off than I thought. Rather than multiplying the 60 minute runtime (on low) by the 270 lumen brightness (on high) from the 5.11 data sheet, you have somehow posited 270 lumens for 1.5 hours - which seems to have come straight out of thin air.

      This means that your calculations are off by a factor of six.

  4. Re:Hmm... by Anonymous+Monkey · · Score: 5, Funny

    None for me, thanks. I'm driving.

    --
    We are the Borg...
  5. Comment removed by account_deleted · · Score: 3, Funny

    Comment removed based on user account deletion

  6. Re:Hmm... by Java+Pimp · · Score: 4, Funny

    I was gonna mod this as Funny cause I almost spit out my Pepsi when I read this. Then I saw someone modded it Informative...

    Then I did spit out my Pepsi.

    --
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