There is no set voltage that can move through the wire sizes, but the general rule is that thinner wires should be used for low-voltage needs, and thicker wires should be used for high-voltage needs. Follow this detailed guide for a smooth installation of your solar battery cabinet and maximize. Battery cable gauge size charts help you choose the correct cable thickness for your power needs, ensuring safety, performance, and longevity. Have you ever wondered why your battery struggles even when it's fully charged? It might not be the battery—it could be the cable. This chapter explains why and contains other useful information on what to look out for when designing a system's DC wiring. Cable selection The correct cable can only be selected once you know the currents in a system. To find. A wider pipe can carry more water, and a thicker wire (which has a lower gauge number) can carry more electricity. The American Wire Gauge (AWG) system is what most people use.