Planar Litz coil for wireless power transfer

Structures, devices, and methods for wireless power transfer systems are described. A structure can include a plurality of strands arranged into a first coil layer and a second coil layer. The plurality of strands can be formed on a parallel path surrounding a center of the structure. The plurality of strands can extend away from the center on the first coil layer. The plurality of strands can extend towards the center on the second coil layer. For every fixed interval along a length of the structure, a first strand among the plurality of strands can be looped from the first coil layer to the second coil layer and a second strand among the plurality of strands can be looped from the second coil layer to the first coil layer.