Electronics, Lighting, & Gadgets - big battery, heated socks

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View Full Version : big battery, heated socks


john bono
11-05-07, 12:32 PM
I've built a homebrew mr-11 triple cree kit, and I think I bought a battery that is bigger than I needed to drive it for most of my uses. From what I can tell, my 14.4 5000AH bottle battery will give me something like 7 hours of continuous light driving 3 crees at 1000ma, so for my winter commutes, I have enough power to do rides for two to four days light for my evening commute, which means I have a lot of extra power left at my disposal for other uses.

Since it is winter, I would like to wire up the battery to a pair of heated socks/insoles to make the commute more comfortable. Most of the socks I've seen run on either a D cell or a pair of AAs, which means that I need to convert the 14.4+v of the bottle battery down to 1.2 to 3 volts depending on the sock/insole. The problem is that I am an absolute electronics novice when it comes to resistors, capacitors, etc. So how do I create a circuit that will give me 1.2 to 3 volts from a 14.4 source with a minimum of fuss?


ovrrdrive
11-05-07, 01:18 PM
The easiest way would be to solder leads to one of the batteries if you can get at them. You have to series 12 1.5V batteries to get 14.4V, if you use the top and bottom of only one of them you will get 1.5V depending on what pack you have...

sv_ted
11-05-07, 02:29 PM
Look up Dimension Engineering. They make small switching regulators that you can use to output a variable voltage. I am using one to run my rear blinkers off of my 14.4v Li-Ion battery. There is a pot on the regulators to set the voltage to whatever you want. I run 3.2v to my blinkers.


diff_lock2
11-05-07, 04:40 PM
How cold does it get?! At -20c + wind i still didn't need chemical or electrical heating. If i where walking, maybe. I use layers, works very well.

john bono
11-06-07, 11:15 AM
With my booties, and wool socks, I start to feel a mild chill at the end of my commute w/my road shoes at about 40 degrees, and if anything my mtb shoes are worse(steel cleats and a smaller shoe) Right now, it isn't a big deal, and I can do without for the time being. In six weeks, though, it will be, and I need to ride through the winter, which was something I didn't do last year, and i paid for it in may and june.