BIKE LIGHT "Commuter" under 5 bucks By Veggiecycle

Step 6 Battery ...now this is gonna cost you a little bit (same as my other bike light)

You need to find at Radio Shack or a specalty electronics supply for a 10 AA batteries holder. Solder the other end of the RCA cable to it and ....
The best battery to use is a Nickel-Metal Hydride or NiMH 2500 mAh I found the Energizer from HD the best price. You need 10 cuz they are 1.2 volts each 10x1.2 = 12 volts. Put the battery pack in your underseat bag or in a water bottle. The light should work for 3 hours with this 11 watt bulb and 10 2500 mAh batteries.
If you have any questions drop me a line....

10 AAbattery holder $1.00
Energizer 4-Pack AA NiMH Rechargeable $8.97HD
Energizer 4-Pack AA NiMH Rechargeable w/charger 17.95
I got this bike water bottle battery pack that is 5 mah with the quick charger from http://www.batteryspace.com They have tons of great batteries on that site.

Comments

[mista.v]

Why not just use a straight up 12 volt like this?
http://www.google.com/products/catalog?q=12+volt+battery&um=1&hl=en&biw=1436&bih=807&ie=UTF-8&cid=2415590567703803192&ei=Ce40TYu2LMGs8AaB3vTwCA&sa=X&oi=product_catalog_result&ct=result&resnum=3&ved=0CH8Q8wIwAg#
(or the giantass ones in the hardware store)

[bullzebub]

You should get a battery pack from http://cheapbatterypacks.com/main.asp
it would give you better "bang for the buck" and it would be easier to make :-)

or maybe a batterypack from a cordless powertool.