Abstract: An electric motor includes a stator and a rotor. The stator includes a stationary shell, a polymer element located in the stationary shell, a coil unit located in the polymer element, two covers each connected to a related one of two opposite sides of the stationary shell, two caps each attached to a related one of the covers, and two bearings each fit in a related one of the caps. The rotor includes an axle inserted through the coil unit and supported on the bearings, two shields each connected to a related one of two opposite sides of the axle, and two groups of magnets. Each of the groups of magnets is connected to a related one of the shields.