Battery Cable Sizing Guide

Whether you are changing or resizing your car battery or a deep-cycle battery bank for a renewable energy system, it is important to use the correctly sized battery in order to optimize the electricity that goes into and comes out of your battery.

Renewable Energy Systems

  • Most battery banks used for renewable energy systems have short wire lengths and utilize either six-, 12- or 24-volt batteries. Typically, eight-gauge wire is used for linking the battery bank into a series circuit for renewable energy systems, such as solar and wind turbine generators. Otherpower recommends using #2/0 welding cable, although it is much more expensive than ordinary AWG (American Wire Gauge) cable.

Wire Composition

  • The wire's composition, whether aluminum, copper, silver or another metal is used, will help to determine the size of the battery cable. Copper is the most commonly used wire for batteries and electrical systems, although you may want to use a wire composition type that has a greater efficiency, such as silver, depending on your project.

Other considerations

  • Typically, wire and cables must be sized to the amperage of the battery system and the length required for the wires to travel from point A to point B. Consulting a wire size chart will help to determine the correct size cable to use for your battery system.