What wire gauge do you use for your battery leads? Most people use either 14 gauge or 12 gauge. You probably know that thinner wire has more voltage drop and delivers less power. But how much does this effect actually matter? Tonight, I did a test that might answer that question.

The worst-case scenario that I considered was a 10 cm wire and 120 amps discharge rate. Based on that assumption, the 12 gauge wire will drop 0.06 volts while the 14 gauge wire will drop 0.1 volts. The 14 gauge wire loses 5 watts more than the 12 gauge wire. If you are using shorter wire than 10 cm, or pulling less than 120 amps, these numbers only get smaller.

You might think that it’s obvious that the thicker 12 gauge wire gives higher performance. In fact, I’ve complained sometimes about high-performance batteries coming from the factory with 14 gauge wire leads. But these results seem to call that into question. Even if we were to double the wire length to 20 cm, we’re only losing 10 or so watts, worst-case. When you consider that a quad might pull 3000 or 4000 watts at full throttle, 5 or 10 watts lost to the battery lead hardly seems to matter.