An automotive charging system is made up of three major components the battery, the voltage regulator and an alternator. The alternator works with the battery to generate power for the electrical components of a vehicle, like the interior and exterior lights, and the instrument panel. An alternator gets its name from the term alternating current (AC). Alternators are typically found near the front of the engine and are driven by the crankshaft, which converts the pistons' up-and-down movement into circular movement.