Hey guys! I have been following the forum for quite some time now. With all of you smart people out there, Im hoping you can help me design a heater, or at least lead me in the right direction. What I am attempting to create is a battery powered heater, to maintain a temperature of between 40 degrees Fahrenheit and 60 degrees fahrenheit. I have done quite a bit of research. I have thought to use Nichrome wire, a total of about 36 inches. So the known so far is, 36 inches, and a temperature of about 50 degrees. However here is the kicker: I need to power this via battery, during the winter. I will use thermal switches to begin and end the circuit. So it will not run constantly. I estimate it will run 8 hours a day. So at 8 hours a day, I need 36 inches of nichrome wire to heat at 50 degrees with NO maintenance for around 4 months. 8 hours x 120 days is 960 hours run time. I realize this is quite a demand, and I'm not sure if i can get this done, but I'm sure its possible. Problems are made to solve right?! The battery type is an unknown, and the gauge of the wire unknown. Any advice guys would help. Battery type? Configuration? Nichrome Wire gauge? Thanks guys!