cooler wire conducts electricity better....each wire has a bit of resistance..the more current u put through it,the hotter it gets..something like the heating element in your water kettle..except that the heating element has high resistance compared to ur normal wire...so if u wait a while so that it cools u can get a very little more electricity through it..but its insignificant if its only a few degrees different..if u can cool the wire to -273 C u have a superconductor with 0 resistance..
