Brightes 3mm led powered by cr1220 button battery?

My keychain pocket knife has a 3mm red led built in the handle, powered by a button battery-cr1220 I believe. I wan to get a white led that is as brigt as possible that is compatable with the battery source. Any help would be greatly appreciated

There will always be a tradeoff between runtime and brightness. I think the most you can get out of that sort of LED is about 10 lumens for a few hours. Do you want flood (Wide light spread, good for close work) or throw (Narrow beam, better for spotting more-distant things)?

If the LED light comes off the knife, it'd be nice to wrap something around it so that you can hold it in your teeth to work with. In this use scenario, you'd want a wide-spread LED.

I like having a decent amount of throw, but the flood is probably Gona be more useful. And the led is inserted in the middle of the handle, the plastic carrier pools out of the handle and houses the button battery, then the bare led lies on top and slides in place. Activated by a button on the side if the knife. Any good places I could buy from? Or a specific led maker

Nichia BS - 3mm LED

This is the brightest. Good luck finding one as ebay has them from time to time. This is going to produce a throw and tint of a CS 5mm led but in a smaller slightly less brighter package.

Link: http://www.led1.de/shop/lng/en/nichia-led-3mm-white-18900mcd-nspw300ds.html

Then ebay has 20000mcd ones that come in the 5000k-6000k range.

Nichia is going to be worth the extra dollar or two and would love to buy a few as well if you can find a place.

Thanks guys, now all there is to do is find a place that sells them

ledrise.com is great as i just ordered 120 degree 5mm nichia gs leds and gonna put some in my nokero solar bulbs and get a jump from 13.5 lumen of flood to 30-50 lumen of flood. I cant wait to see the color of the nichia gs in flood instead of the e01 style 15 degree to 20 degree lens.

If the color is the same and the beam is nice and even, its the perfect low level led. 40 bucks shipped for 50 leds is great and I even got 2 xp-g q5 warm leds on a star for 6 bucks shipped as well(as I had to grab two). Great site and prices you can't argue. DX is for last case scenario now.

Nichia does make nice LEDs, but they are very difficult to source, as their focus is entirely on high volume customers. Similar performance can come from the Cree product line, and it is a lot easier to find them from a supplier such as mouser / newark / digikey.

If your goal is "throw", then you will want a narrow angle LED - as narrow as you can find, even at the cost of lower lumens.

Before you install that LED in your knife though, it might be worth checking to make sure it will actually light up. Red LEDs have a Vf of approx 2 volts, while white LEDs have a Vf of approx 3 volts. The cell in that knife is a nominal 3 volts, so it will just barely do the job, and certainly will have shorter run time. I am not saying it won't work, but it is worth testing first.

It might be possible to find a red / orange LED (about 615 - 625 nm) in the format you like. This will be quite bright, and have a similar Vf to the one that is in there now.