Twisted wire for power charging

1. A device for generating or receiving wireless power via a magnetic field at a level sufficient to power or charge an electronic device, comprising:

a first coil configured to generate or receive wireless power via a magnetic field, the first coil comprising one or more first windings each having a substantially rectangular cross-section with at least a first surface having a first width and a second surface orthogonal to the first surface having a second width greater than the first width, each of the first windings comprising:

a first segment having the first surface oriented horizontally and the second surface in the first segment oriented vertically relative to a surface of a housing structure; and

a second segment having the first surface in the second segment oriented vertically and the second surface in the second segment oriented horizontally relative to the surface of the housing structure, the second segment connected to the first segment via a twisted segment;

wherein the first segments of the first windings are arranged in a single-stacked arrangement in a first portion of the first coil, and the second segments of the first windings are arranged in a double-stacked arrangement in a second portion of the first coil.

2. The device of claim 1 , further comprising a second coil configured to generate or receive wireless power via the magnetic field, the second coil comprising one or more second windings each having a substantially rectangular cross-section with at least a first surface having a first width and a second surface orthogonal to the first surface having a second width greater than the first width, each of the second windings comprising:

a first segment having the first surface oriented horizontally and the second surface in the first segment oriented vertically relative to the surface of the housing structure; and

a second segment having the first surface in the second segment oriented vertically and the second surface in the second segment oriented horizontally relative to the surface of the housing structure, the second segment connected to the first segment via a twisted segment.

3. The device of claim 2 , wherein the device comprises a double D (DD) coil having the first coil enclosing a first area and the second coil coplanar to the first coil enclosing a second area, and wherein the first and second coils share a common central portion.

4. The device of claim 3 , wherein the first segments of the first and second coils are configured to be parallel to each other in at least a portion of the common central portion of the DD coil.

5. The device of claim 1 , wherein the first coil having an enclosed area, and wherein the first coil comprises an output portion extending from the first segment and forming a bend within the area enclosed by the first coil.

6. The device of claim 1 wherein the first coil comprises a litz wire.

7. The device of claim 1 , wherein the twisted segment is twisted 90 degrees.

8. The device of claim 1 , wherein the first and second segments of a first winding of the one or more first windings are substantially coplanar.

9. An apparatus for wirelessly transferring power, comprising:

a first coil configured to wirelessly receive power via a magnetic field, the first coil comprising one or more litz wires each having a rectangular cross section with a first longer side and a second shorter side; and

a second coil configured to wirelessly receive power via a magnetic field, the second coil comprising one or more of the litz wires and the positioned to be at least partially coplanar with the first loop;

wherein each of the first and second loops comprises a plurality of litz wires, each having a rectangular cross section with a first longer side and a second shorter side, and

wherein the one or more litz wires of the first and second coils are twisted such that a width of the first and second coils at a first location is defined by the first longer side of the one or more litz wires, and a width of the coils at a second location is defined by the second shorter side of the one or more litz wires.

10. The apparatus of claim 9 , further comprising a housing structure configured to house the first and second coils;

wherein the first location is located in a central portion of the housing and the second location is located at a portion of a perimeter of the housing structure.

11. The apparatus of claim 9 , wherein the litz wires are twisted 90 degrees between an outer portion and an inner portion of the first and second loops.

12. The apparatus of claim 11 , wherein the inner portions of the first and second loops are directly adjacent to each other.

13. The apparatus of claim 9 , further comprising an output portion extending from a single-stacked inner portion and forming a bend within either the first location or second location.

14. A method of winding coils of a charging device for generating or receiving wireless power via a magnetic field at a level sufficient to power or charge an electronic device, comprising:

positioning a first coil comprising one or more rectangular litz wires having a length greater than a width such that the length is parallel with a plane of the charging device in a first region of the charging device and perpendicular with the plane in a second region of the charging device;

wherein the one or more rectangular litz wires are arranged in a double-stacked arrangement in the first region and a single-stacked arrangement in the second region.

15. The method of claim 14 , further comprising:

positioning a second coil comprising one or more of the rectangular litz wires such that the length is parallel with the plane in a third region of the charging device and perpendicular with the plane in the second region of the charging device.

16. The method of claim 15 , wherein the first and third regions are located at a perimeter of the charging device and the second region is located in a central location of the charging device.