You need heavier gauge wire (a lower gauge number). Wire Gauge Chart
Normally we just assume wire has zero resistance but it does have some resistance depending on gauge and length. A fatter or shorter wire has less resistance.
When current flows through a resistance we get a voltage drop (Ohm's Law) and voltage & current together make power (energy & heat). If we can reduce the wire resistance, we reduce the voltage drop and the heat.
A shorter wire will also reduce the resistance but the remaining heat is more concentrated so it doesn't help with the wire heating. (It does help with voltage drop/loss which can also be a problem.)