Patent attributes
A wireless power transfer device is disclosed that includes at least a first coil layer and a second coil layer, each coil layer including two coil windings positioned adjacent to one another in a lateral direction; wherein the two coil windings in each corresponding coil layer are connected in series and are wound in the same rotational direction, and the first and second coil layers are stacked in layers on top of one another. The magnetic fields of the coil layers can interact with one another in a constructive manner such that the overall efficiency and power transmission of the wireless power transfer device can be enhanced.