Alternator

An alternator, also called a synchronous generator, is an electrical generator that converts mechanical energy into alternating current electricity, typically by rotating a magnetic field within a stationary set of armature coils rather than the reverse. The device grew out of the electromagnetic induction research of the 1830s, most notably Michael Faraday's discovery of induction and the early generator work of the French instrument maker Hippolyte Pixii, and it developed gradually over the nineteenth century rather than through a single inventor or patent date. Small alternators became the standard method of charging a vehicle's battery and powering its electrical systems while the engine runs, and the same basic design, at far larger scale, generates most of the alternating current supplied by power stations worldwide.