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Nearly every factory-standard accessory in your car is powered by your vehicle’s battery. Sometimes, however, you need a little more juice, which is exactly what an auxiliary car battery will provide.

Auxiliary batteries have been installed in vehicles for several decades, particularly those powered by diesel engines and used for recreation. The introduction of hybrid vehicles has also increased the need for auxiliary batteries. And today, aux batteries are gaining traction with car owners whose engines are driven by unleaded gasoline as well. In fact, some manufacturers factory install auxiliary batteries in unleaded gas powered cars.

So what are aux car batteries?

In an unleaded gas powered vehicle, aux batteries are a second 12 volt car battery designed to take some of the strain away from the main one. They are used for multiple applications, including the job of running non-standard accessories installed in cars. Some common uses for aux batteries include:

  • Powering a high performance aftermarket audio system like those installed to enter competitions
  • Providing electricity to run tailgating gear, including televisions, stereos, and cooking appliances
  • Outfitting your car to power camping gear, such as lights, heating elements, and cooking appliances

Hybrid vehicles, which are still gaining popularity amongst new car buyers, have drivetrains powered by high voltage traction batteries. As a means of reducing stress on the traction battery, hybrid cars rely on auxiliary 12 volt batteries. Because of the 12 volt auxiliary car battery, the isolated high voltage battery is not subjected to the normal drain that occurs when a vehicle isn’t running. This includes the computer and its internal “keep-alive” memory, clock, and related settings that all draw a small amount of current when the vehicle is off. Additionally, the 12 volt auxiliary car battery keeps all of the accessories such as lighting, safety, and entertainment systems powered up when the engine is not running.

Speak with a Pep Boys certified technician today to see if your current auxiliary car battery needs replacing or if having one installed can benefit you.