What is the usual voltage of a vehicle battery?

The usual voltage of a vehicle battery is 12 volts. This standard is primarily due to the design of the electrical system in most vehicles, which typically use a 12-volt lead-acid battery to power various components, including the starter motor, lights, and onboard electronics.

A 12-volt system is effective for automotive use as it provides sufficient power to start the engine while keeping the size and weight of the battery manageable. In practice, while some smaller vehicles and older automotive systems may have operated on 6-volt batteries, 12 volts became the industry standard by the mid-20th century due to its advantages in output and efficiency.

In contrast, voltage levels such as 24 volts or 36 volts are generally found in larger vehicles like trucks or military equipment that require more power to run larger engines and more extensive electrical systems. However, for typical passenger cars and light trucks, the 12-volt battery remains the predominant choice.