I'll be up-front and say I know jack squat about electrical engineering aside from "conductors heat up when you run current through them."
I'm looking in to building a low-voltage (~12-24 volts) personal heater that I can attach to the inside of a jacket; basically a small battery-powered electric blanket with no control system other than just unplugging the battery when it gets too hot and plugging it back in when it gets too cold. I'm not sure how possible this is to do safely though.
My main question is, what should I use for the heating coil? I was hoping to have a long wire that zig-zags over most of the back of the inside of the jacket. Kanthal wire is really cheap right now 'cos of all the people wanting to build vaporizers; is that an appropriate material? If so, what specific mixture and gauge should I be going for?
Looking at the specifics it seems like it's meant for extremely high temperatures, whereas I want something that stays around 30-40 degrees Celsius on low voltage. I can't seem to find anything that says it's designed for that kind of application, though. Am I barking up entirely the wrong tree?
Is this a practical idea at all?