US Patent 10144302 Twisted wire for power charging

Systems and methods for a twisted rectangular litz wire for generating or receiving wireless electrical power. The rectangular litz wire may be arranged as a DD coil having first and second co-planar loops. The loops may have a shared single-stacked inner portion and double-stacked outer portions. The litz wire may be twisted between the inner and outer portions, such that a width of the coils at the outer portions is defined by a first longer side of the wires, and a width of the coils at the inner portion is defined by a second shorter side of the wires. This arrangement may reduce a size of the DD coil may reducing a width of the shared inner portion.