I am looking for a product that may not exist. I need to find a very
small LED light that has it?s own attached power source.  All total
the LED light and power source should be enclosed in a space
approximately 2mm x 2mm x 2mm.  The light does not have to be very
bright, but this needs to be continuously ?on? for 10 years or longer.
I have checked with LED manufactures and they do make small LED
lights, but the attached power source may be the problem.  All total
this unit that I need is a small part of a bigger project, and needs
to be self enclosed.  It may be that this product does not exist in
the form that I need it, but if I could find the LED light and power
source separately I may be able to combine the two.  Once again the
entire unit needs to provide a continuous low beam of light for 10
years or more, and be about to be placed in a space in the area of 2mm
x 2mm x 2mm.  Thanks

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Request for Question Clarification by hedgie-ga on 05 Dec 2005 05:53 PST

1) Can you make specification
     "The light does not have to be very bright"
  more exact? How many candelas, or  Watts or visible by average person
  form X meters 
http://www.electro-optical.com/whitepapers/candela.htm

2) Would a negative response (showing it impossible) be acceptable answer?

This site may not be the latest information, but it seems quite detailed.

http://www.maxmax.com/aFlashLED_SubMini.htm

I don't believe you can pack enough battery power into your 2.2.2mm,
much less enough to last for ten years.

Smallest Battery I could find.....

http://www.wired.com/news/medtech/0,1286,60706,00.html

2.9 mm in diameter and 13 mm in length. With recharging, last up to 10 years.

I dont think you are even going to get a battery which fits in a 2x2x2 cube.

LEDs can be less than 1 mm cubed, at the diode junction.
 Doubt if a standard-technology battery exists which is small enough.
There's some proposed 'atomic-battery' technology which could be small
enough, about 1 mm cube and 50-year life, but don't know if there's
enough power. ( http://www.technologyreview.com/Hardware/wtr_14548,294,p1.html
and http://www.geek.com/news/geeknews/2002Nov/bpd20021105017150.htm )
These betteries are probably no commercial yet, if ever.
 What about the old glow-in-the-dark material used on watches, which
are also powered by radio-isotopes such as tritium ? Haven't found a
source for this type of paint yet, it may be considered too hazardous
for public availability.