PP3 9V Battery Clip Torch

[gotwind2]

The PP3 9V Battery Clip Torch (for 76p)approx 2 U.S dollars

Every year when you change smoke alarm batteries, you can end up with a handful of 9 volt batteries that are essentially ok,  just a little discharged.

If you don't have any other devices that use them, then they often just end up in the bin.

This LED idea clips onto a 9 volt battery and turns it into a pocket emergency torch, that will run for a good few hours as it only draws 20ma current.

A small switch could be fitted, but there is no real need - just clip connector on or off for illumination.

Using one led is a bit wasteful, given that we have 9 volts, you could use two 5mm white leds in series with a 180 ohm resistor, but space gets very limited,

and the volume of light is not that different to one 10mm L.E.D.

Components:

Rigid PP3 Battery clip (Maplin code NE19V) 39p

10. mm White 11000mcd LED (eBay) 24p
    
390. ohm resistor (0.6w)  (Maplin code M390R) 13p
     
     

Just an idea

Ben

www.gotwind.org

[Jon Miller]

Hello Ben,

Good use for a 9v battery, should just say though when the 9v or any battery is no longer of any use they should be disposed of properly as they are very bad for the environment.  Look forward to your next bright idea.

Regards

 

[dinges]

Good idea indeed.

Instead of a Maplin 9V battery clip, one could also take apart an empty 9V battery for its battery clip/connector. That would save another 39p

The ex-battery clip can be mated to a LED and resistor, with the help of a bit of creativity, solder and hotglue.

[tecker]

Nice might be able to get a couple more in there if you can crowd them in

[ghurd]

Switches that fit are not heavy duty enough for the job.  They break!

G-